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Sample records for hubble space telescopes

  1. Hubble Space Telescope satellite

    Science.gov (United States)

    Mitchell, R. E.

    1985-01-01

    The Hubble Space Telescope, named for the American astronomer Edwin Powell Hubble, will be the largest and most powerful astronomical instrument ever orbited. Placed above the obscuring effects of the earth's atmosphere in a 600-km orbit, this remotely-controlled, free-flying satellite observatory will expand the terrestrial-equivalent resolution of the universe by a factor of seven, or a volumetric factor of 350. This telescope has a 2.4-m primary mirror and can accommodate five scientific instruments (cameras, spectrographs and photometers). The optics are suitable for a spectral range from 1100 angstrom to 1 mm wavelength. With a projected service life of fifteen years, the spacecraft can be serviced on-orbit for replacement of degraded systems, to insert advanced scientific instruments, and to reboost the telescope from decayed altitudes. The anticipated image quality will be a result of extremely precise lambda/20 optics, stringent cleanliness, and very stable pointing: jitter will be held to less than 0.01 arcsecond for indefinite observation periods, consistent with instrument apertures as small as 0.1 arcsecond.

  2. Hubble Space Telescope-Illustration

    Science.gov (United States)

    1989-01-01

    This illustration depicts a side view of the Hubble Space Telescope (HST). The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

  3. COSMOS Hubble Space Telescope Observations

    CERN Document Server

    Scoville, N Z; Blain, A W; Calzetti, D; Comastri, A; Capak, P; Carilli, C; Carlstrom, J E; Carollo, C M; Colbert, J; Daddi, E; Ellis, Richard S; Elvis, M; Ewald, S P; Fall, M; Franceschini, A; Giavalisco, M; Green, W; Griffiths, R E; Guzzo, L; Hasinger, G; Impey, C; Kneib, J P; Koda, J; Koekemoer, A; Lefèvre, O; Lilly, S; Liu, C T; McCracken, H J; Massey, R; Mellier, Y; Miyazaki, S; Mobasher, B; Mould, J; Norman, C; Réfrégier, A; Renzini, A; Rhodes, J; Rich, M; Sanders, D B; Schiminovich, D; Schinnerer, E; Scodeggio, M; Sheth, K; Shopbell, P L; Taniguchi, Y; Tyson, N; Urry, C M; Van Waerbeke, L; Vettolani, P; White, S D M; Yan, L

    2006-01-01

    The Cosmic Evolution Survey (COSMOS) was initiated with an extensive allocation (590 orbits in Cycles 12-13) using the Hubble Space Telescope (HST) for high resolution imaging. Here we review the characteristics of the HST imaging with the Advanced Camera for Surveys (ACS) and parallel observations with NICMOS and WFPC2. A square field (1.8$\\sq$\\deg) has been imaged with single-orbit ACS I-F814W exposures with 50% completeness for sources 0.5\\arcsec in diameter at I$_{AB} $ = 26.0 mag. The ACS imaging is a key part of the COSMOS survey, providing very high sensitivity and high resolution (0.09\\arcsec FWHM, 0.05\\arcsec pixels) imaging and detecting a million objects. These images yield resolved morphologies for several hundred thousand galaxies. The small HST PSF also provides greatly enhanced sensitivity for weak lensing investigations of the dark matter distribution.

  4. The Hubble Space Telescope: Problems and Solutions.

    Science.gov (United States)

    Villard, Ray

    1990-01-01

    Presented is the best understanding of the flaw discovered in the optics of the Hubble Space Telescope and the possible solutions to the problems. The spherical aberration in the telescope's mirror and its effect on the quality of the telescope's imaging ability is discussed. (CW)

  5. HUBBLE VISION: A Planetarium Show About Hubble Space Telescope

    Science.gov (United States)

    Petersen, Carolyn Collins

    1995-05-01

    In 1991, a planetarium show called "Hubble: Report From Orbit" outlining the current achievements of the Hubble Space Telescope was produced by the independent planetarium production company Loch Ness Productions, for distribution to facilities around the world. The program was subsequently converted to video. In 1994, that program was updated and re-produced under the name "Hubble Vision" and offered to the planetarium community. It is periodically updated and remains a sought-after and valuable resource within the community. This paper describes the production of the program, and the role of the astronomical community in the show's production (and subsequent updates). The paper is accompanied by a video presentation of Hubble Vision.

  6. Hubble space telescope onboard battery performance

    Science.gov (United States)

    Rao, Gopalakrishna M.; Wajsgras, Harry; Vaidyanathan, Hari; Armontrout, Jon D.

    1996-01-01

    The performance of six 88 Ah Nickel-Hydrogen (Ni-H2) batteries that are used onboard in the Hubble Space Telescope (Flight Spare Module (FSM) and Flight Module 2 (FM2)) is discussed. These batteries have 22 series cells per battery and a common bus that would enable them to operate at a common voltage. It is launched on April 24, 1990. This paper reviews: the cell design, battery specification, system constraints, operating parameters, onboard battery management, and battery performance.

  7. Hubble Space Telescope: A cosmic time machine

    Science.gov (United States)

    Westphal, J. A.; Harms, R. J.; Brandt, J. C.; Bless, R. C.; Macchetto, F. D.; Jefferys, W. H.

    1991-01-01

    The mission of the Hubble Space Telescope (HST) is to explore the expanding and evolving universe. During the 3,000 operating hours every year for the next 15 years or more, the HST will be used to study: galaxies; pulsars; globular clusters; neighboring stars where planets may be forming; binary star systems; condensing gas clouds and their chemical composition; and the rings of Saturn and the swirling ultraviolet clouds of Venus. The major technical achievements - its nearly perfect mirrors, its precise guidance system of rate gyroscopes, reaction wheels, star trackers, and fine guidance sensors are briefly discussed. The scientific instruments on board HST are briefly described. The integration of the equipment and instruments is outlined. The Space Telescope Science Institute (STScI) has approved time for 162 observations from among 556 proposals. The mission operation and data flow are explained.

  8. Hubble Space Telescope Battery Capacity Update

    Science.gov (United States)

    Hollandsworth, Roger; Armantrout, Jon; Rao, Gopalakrishna M.

    2007-01-01

    Orbital battery performance for the Hubble Space Telescope is discussed and battery life is predicted which supports decision to replace orbital batteries by 2009-2010 timeframe. Ground characterization testing of cells from the replacement battery build is discussed, with comparison of data from battery capacity characterization with cell studies of Cycle Life and 60% Stress Test at the Naval Weapons Surface Center (NWSC)-Crane, and cell Cycle Life testing at the Marshal Space Flight Center (MSFC). The contents of this presentation includes an update to the performance of the on-orbit batteries, as well as a discussion of the HST Service Mission 4 (SM4) batteries manufactured in 1996 and activated in 2000, and a second set of SM4 backup replacement batteries which began manufacture Jan 11, 2007, with delivery scheduled for July 2008.

  9. Automation of Hubble Space Telescope Mission Operations

    Science.gov (United States)

    Burley, Richard; Goulet, Gregory; Slater, Mark; Huey, William; Bassford, Lynn; Dunham, Larry

    2012-01-01

    On June 13, 2011, after more than 21 years, 115 thousand orbits, and nearly 1 million exposures taken, the operation of the Hubble Space Telescope successfully transitioned from 24x7x365 staffing to 815 staffing. This required the automation of routine mission operations including telemetry and forward link acquisition, data dumping and solid-state recorder management, stored command loading, and health and safety monitoring of both the observatory and the HST Ground System. These changes were driven by budget reductions, and required ground system and onboard spacecraft enhancements across the entire operations spectrum, from planning and scheduling systems to payload flight software. Changes in personnel and staffing were required in order to adapt to the new roles and responsibilities required in the new automated operations era. This paper will provide a high level overview of the obstacles to automating nominal HST mission operations, both technical and cultural, and how those obstacles were overcome.

  10. A Scientific Revolution: the Hubble and James Webb Space Telescopes

    Science.gov (United States)

    Gardner, Jonathan P.

    2012-01-01

    Astronomy is going through a scientific revolution, responding to a flood of data from the Hubble Space Telescope, other space missions, and large telescopes on the ground. In this talk, I will discuss some of the most important astronomical discoveries of the last IO years, and the role that space telescopes have played in those discoveries. The next decade looks equally bright with the newly refurbished Hubble and the promise of its successor, the James Webb Space Telescope. I will describe how Hubble was upgraded and how and why we are building Webb.

  11. Hubble Space Telescope Crew Rescue Analysis

    Science.gov (United States)

    Hamlin, Teri L.; Canga, Michael A.; Cates, Grant R.

    2010-01-01

    In the aftermath of the 2003 Columbia accident, NASA removed the Hubble Space Telescope (HST) Servicing Mission 4 (SM4) from the Space Shuttle manifest. Reasons cited included concerns that the risk of flying the mission would be too high. The HST SM4 was subsequently reinstated and flown as Space Transportation System (STS)-125 because of improvements in the ascent debris environment, the development of techniques for astronauts to perform on orbit repairs to damaged thermal protection, and the development of a strategy to provide a viable crew rescue capability. However, leading up to the launch of STS-125, the viability of the HST crew rescue capability was a recurring topic. For STS-125, there was a limited amount of time available to perform a crew rescue due to limited consumables (power, oxygen, etc.) available on the Orbiter. The success of crew rescue depended upon several factors, including when a problem was identified; when and what actions, such as powering down, were begun to conserve consumables; and where the Launch on Need (LON) vehicle was in its ground processing cycle. Crew rescue success also needed to be weighed against preserving the Orbiter s ability to have a landing option in case there was a problem with the LON vehicle. This paper focuses on quantifying the HST mission loss of crew rescue capability using Shuttle historical data and various power down strategies. Results from this effort supported NASA s decision to proceed with STS-125, which was successfully completed on May 24th 2009.

  12. Hubble Space Telescope: The Telescope, the Observations & the Servicing Mission

    Science.gov (United States)

    1999-11-01

    Today the HST Archives contain more than 260 000 astronomical observations. More than 13 000 astronomical objects have been observed by hundreds of different groups of scientists. Direct proof of the scientific significance of this project is the record-breaking number of papers published : over 2400 to date. Some of HST's most memorable achievements are: * the discovery of myriads of very faint galaxies in the early Universe, * unprecedented, accurate measurements of distances to the farthest galaxies, * significant improvement in the determination of the Hubble constant and thus the age of the Universe, * confirmation of the existence of blacks holes, * a far better understanding of the birth, life and death of stars, * a very detailed look at the secrets of the process by which planets are created. Europe and HST ESA's contribution to HST represents a nominal investment of 15%. ESA provided one of the two imaging instruments - the Faint Object Camera (FOC) - and the solar panels. It also has 15 scientists and computer staff working at the Space Telescope Science Institute in Baltimore (Maryland). In Europe the astronomical community receives observational assistance from the Space Telescope European Coordinating Facility (ST-ECF) located in Garching, Munich. In return for ESA's investment, European astronomers have access to approximately 15% of the observing time. In reality the actual observing time competitively allocated to European astronomers is closer to 20%. Looking back at almost ten years of operation, the head of ST-ECF, European HST Project Scientist Piero Benvenuti states: "Hubble has been of paramount importance to European astronomy, much more than the mere 20% of observing time. It has given the opportunity for European scientists to use a top class instrument that Europe alone would not be able to build and operate. In specific areas of research they have now, mainly due to HST, achieved international leadership." One of the major reasons for

  13. The Hubble Space Telescope Frontier Fields Program

    Science.gov (United States)

    Koekemoer, Anton M.; Mack, Jennifer; Lotz, Jennifer M.; Borncamp, David; Khandrika, Harish G.; Lucas, Ray A.; Martlin, Catherine; Porterfield, Blair; Sunnquist, Ben; Anderson, Jay; Avila, Roberto J.; Barker, Elizabeth A.; Grogin, Norman A.; Gunning, Heather C.; Hilbert, Bryan; Ogaz, Sara; Robberto, Massimo; Sembach, Kenneth; Flanagan, Kathryn; Mountain, Matt

    2017-08-01

    The Hubble Space Telescope Frontier Fields program is a large Director's Discretionary program of 840 orbits, to obtain ultra-deep observations of six strong lensing clusters of galaxies, together with parallel deep blank fields, making use of the strong lensing amplification by these clusters of distant background galaxies to detect the faintest galaxies currently observable in the high-redshift universe. The entire program has now completed successfully for all 6 clusters, namely Abell 2744, Abell S1063, Abell 370, MACS J0416.1-2403, MACS J0717.5+3745 and MACS J1149.5+2223,. Each of these was observed over two epochs, to a total depth of 140 orbits on the main cluster and an associated parallel field, obtaining images in ACS (F435W, F606W, F814W) and WFC3/IR (F105W, F125W, F140W, F160W) on both the main cluster and the parallel field in all cases. Full sets of high-level science products have been generated for all these clusters by the team at STScI, including cumulative-depth data releases during each epoch, as well as full-depth releases after the completion of each epoch. These products include all the full-depth distortion-corrected drizzled mosaics and associated products for each cluster, which are science-ready to facilitate the construction of lensing models as well as enabling a wide range of other science projects. Many improvements beyond default calibration for ACS and WFC3/IR are implemented in these data products, including corrections for persistence, time-variable sky, and low-level dark current residuals, as well as improvements in astrometric alignment to achieve milliarcsecond-level accuracy. The full set of resulting high-level science products and mosaics are publicly delivered to the community via the Mikulski Archive for Space Telescopes (MAST) to enable the widest scientific use of these data, as well as ensuring a public legacy dataset of the highest possible quality that is of lasting value to the entire community.

  14. How Long Can the Hubble Space Telescope Operate Reliably?

    Science.gov (United States)

    Xapsos, M. A.; Stauffer, C.; Jordan, T.; Poivey, C.; Lum, G.; Haskins, D. N.; Pergosky, A. M.; Smith, D. C.; LaBel, K. A.

    2014-01-01

    Total ionizing dose exposure of electronic parts in the Hubble Space Telescope is analyzed using 3-D ray trace and Monte Carlo simulations. Results are discussed along with other potential failure mechanisms for science operations.

  15. Beyond the Hubble Space Telescope: Early Development of the Next Generation Space Telescope

    Science.gov (United States)

    Smith, Robert W.; Patrick McCray, W.

    In this paper we investigate the early history of what was at first called the Next Generation Space Telescope, later to be renamed the James Webb Space Telescope. We argue that the initial ideas for such a Next Generation Space Telescope were developed in the context of the planning for a successor to the Hubble Space Telescope. Much the most important group of astronomers and engineers examining such a successor was based at the Space Telescope Science Institute in Baltimore. By the late 1980s, they had fashioned concepts for a successor that would work in optical, ultraviolet and infrared wavelengths, concepts that would later be regarded as politically unrealistic given the costs associated with them. We also explore how the fortunes of the planned Next Generation Space Telescope were intimately linked to that of its "parent," the Hubble Space Telescope.

  16. Early Scientific Results from the Rejuvenated Hubble Space Telescope

    Science.gov (United States)

    Niedner, Malcolm

    2010-01-01

    With the complete success of Servicing Mission 4 (SM4) to the Hubble Space Telescope in May, 2009, the Observatory's capabilities are extremely broad and beyond anything it has previously been equipped with. I will present results on the important early science corning out of the telescope and discuss prospects for the future."

  17. Hubble Space Telescope On-orbit Transfer Function Test

    Science.gov (United States)

    Vadlamudi, N.; Blair, M. A.; Clapp, B. R.

    1992-01-01

    The paper describes the On-orbit Transfer Function Test (TFT) designed for on-orbit vibration testing of the Hubble Space Telescope (HST). The TFT provides means for extracting accurate on-orbit characteristics of HST flexible body dynamics, making it possible to check periodically the state of the vehicle on-orbit and to assess changes in modal parameters.

  18. Astrometry with Hubble Space Telescope Fine Guidance Sensors - A Review

    CERN Document Server

    Benedict, G Fritz; Nelan, Edmund P; Harrison, Thomas E

    2016-01-01

    Over the last 20 years Hubble Space Telescope Fine Guidance Sensor interferometric astrometry has produced precise and accurate parallaxes of astrophysical interesting stars and mass estimates for stellar companions. We review parallax results, and binary star and exoplanet mass determinations, and compare a subset of these parallaxes with preliminary Gaia results. The approach to single-field relative astrometry described herein may continue to have value for targets fainter than the Gaia limit in the coming era of 20-30m telescopes.

  19. European astronaut selected for the third Hubble Space Telescope

    Science.gov (United States)

    1998-08-01

    The STS-104 crew will rendezvous with the orbiting Hubble Space Telescope, which is the size of a city bus, capture it using the Shuttle's Canadian robot arm and secure it in Columbia's payload bay. Then, working in teams of two, the four astronauts will leave the Shuttle's pressurised cabin and venture into the payload bay, performing a variety of tasks that will improve the productivity and reliability of the telescope. The four astronauts will perform a series of six "extravehicular" activities in the open space environment. Such activities are commonly called spacewalks, but this term does little justice to the considerable physical and mental efforts that astronauts need to make in doing the very demanding work involved. The Shuttle commander and pilot for this flight have not yet been appointed, but the four designated mission specialists begin training for the STS-104 mission immediately. "The ambitious nature of this mission, with its six spacewalks, made it important for the payload crew to begin training as early as possible," said David C. Leestma, NASA Director of Flight Crew Operations at the Johnson Space Center in Houston, to which Claude Nicollier is on resident assignment from ESA's European Astronaut Centre in Cologne, Germany, the home base of the European astronaut corps. The Hubble Space Telescope was launched into orbit in April 1990. It is one of the most capable optical telescopes available to astronomers today, producing images and spectral observations at the forefront of astronomy. The European Space Agency contributed a 15 share to the development of Hubble. One of the five scientific instruments on board, the Faint Object Camera, was built by a European industrial consortium made up of British Aerospace, Dornier and Matra under a contract with the European Space Agency. The solar arrays which provide Hubble with electrical power were manufactured by British Aerospace and Dornier. In its eight years of operation, the telescope has not

  20. Technicians assembly the Hubble Space Telescope (HST) mockup at JSC

    Science.gov (United States)

    1989-01-01

    At JSC's Mockup and Integration Laboratory (MAIL) Bldg 9A, technicians install a high gain antenna (HGA) on the Hubble Space Telescope (HST) mockup. On the ground a technician operates the controls for the overhead crane that is lifting the HGA into place on the Support System Module (SSM) forward shell. Others in a cherry picker basket wait for the HGA to near its final position so they can secure it on the mockup.

  1. Feasibility of Exoplanet Coronagraphy with the Hubble Space Telescope

    Science.gov (United States)

    Lyon, Richard G.; Woodruff, Robert A.; Brown, Robert; Noecker, M. Charley; Cheng, Edward

    2010-01-01

    Herein we report on a preliminary study to assess the use of the Hubble Space Telescope (HST) for the direct detection and spectroscopic characterization of exoplanets and debris disks - an application for which HST was not originally designed. Coronagraphic advances may enable the design of a science instrument that could achieve limiting contrasts approx.10deg beyond 275 milli-arcseconds (4 lambda/D at 800 nm) inner working angle, thereby enabling detection and characterization of several known jovian planets and imaging of debris disks. Advantages of using HST are that it already exists in orbit, it's primary mirror is thermally stable and it is the most characterized space telescope yet flown. However there is drift of the HST telescope, likely due to thermal effects crossing the terminator. The drift, however, is well characterized and consists of a larger deterministic components and a smaller stochastic component. It is the effect of this drift versus the sensing and control bandwidth of the instrument that would likely limit HST coronagraphic performance. Herein we discuss the science case, quantifY the limiting factors and assess the feasibility of using HST for exoplanet discovery using a hypothetical new instrument. Keywords: Hubble Space Telescope, coronagraphy, exoplanets, telescopes

  2. 18 years of science with the Hubble Space Telescope.

    Science.gov (United States)

    Dalcanton, Julianne J

    2009-01-01

    After several decades of planning, the Hubble Space Telescope (HST) was launched in 1990 as the first of NASA's Great Observatories. After a rocky start arising from an error in the fabrication of its main mirror, it went on to change forever many fields of astronomy, and to capture the public's imagination with its images. An ongoing programme of servicing missions has kept the telescope on the cutting edge of astronomical research. Here I review the advances made possible by the HST over the past 18 years.

  3. The Hubble Space Telescope Education and Public Outreach Program

    Science.gov (United States)

    Teays, T. J.; Eisenhamer, B.; Eisenhamer, J.; Amazing Space Team

    2001-05-01

    The Hubble Space Telescope has conducted a long-standing and vigorous program in education and public outreach. This program uses a variety of methods to reach a broad spectrum of audiences. Education products are developed in a team environment that partners educators, curriculum experts, scientists, and production experts, such as graphic artists, Web designers, programmers, and education evaluators. A popular Web site is maintained, and has been substantially augmented in the past year. The Amazing Space program consists of a suite of online, interactive modules for use in the kindergarten through 12th grade classroom. The program is rooted in the national education standards and benefits from a robust evaluation process. The HST images and data are used to engage students in learning basic science and mathematics concepts. The activity/lessons include extensive, online assistance for educators, so that they can be readily used in the classroom. Hardcopy products such as posters, lithographs, teacher guides, and trading cards are generally tied to online products, to provide multiple entries to the material. We also provide training for teachers in the use of our products, as appropriate. Informal science education is supported by providing services to museums, planetariums, libraries and related institutions. The very popular ViewSpace, a computer-based video service is being used by many informal science facilities. In addition, HST has supported the creation of both permanent and traveling exhibits about HST. The Space Telescope Science Institute operates the Hubble Space Telescope for NASA.

  4. Asteroid observations with the Hubble Space Telescope and the Space Infrared Telescope Facility

    Science.gov (United States)

    Zellner, B.; Wells, Eddie N.; Chapman, Clark R.; Cruikshank, D. P.

    1989-01-01

    The ways that the asteroids can be studied with the Hubble Space Telescope (HST) and the Space Infrared Telescope Facility (SIRTF) are examined. Spectrophotometry of asteroids and the study of asteroid surfaces, shape, spins, configuration, normal reflectance, and limb darkening of asteroids using the HST are addressed along with the detection of asteroid satellites and the discovery of small asteroids using the HST. The relation of the HST to its ground system is described, as are the spectrophotometric instruments of the HST. Imaging with the HST using the Faint Object Camera and the Wide Field and Planetary Camera is examined. Finally, the SIRTF observatory, instrumentation, and capabilities for solar system science are discussed.

  5. Hubble Space Telescope: Latest citations from the EI Compendex*Plus Database

    Science.gov (United States)

    1996-02-01

    The bibliography contains citations concerning the Hubble Space Telescope and its mission. Topics include design changes, flight performance, and initial problems encountered. The Hubble's solar arrays and observations of space are discussed.

  6. Observing supernova 1987A with the refurbished Hubble Space Telescope.

    Science.gov (United States)

    France, Kevin; McCray, Richard; Heng, Kevin; Kirshner, Robert P; Challis, Peter; Bouchet, Patrice; Crotts, Arlin; Dwek, Eli; Fransson, Claes; Garnavich, Peter M; Larsson, Josefin; Lawrence, Stephen S; Lundqvist, Peter; Panagia, Nino; Pun, Chun S J; Smith, Nathan; Sollerman, Jesper; Sonneborn, George; Stocke, John T; Wang, Lifan; Wheeler, J Craig

    2010-09-24

    Observations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 with the use of the refurbished instruments on HST with data taken in 2004, just before the Space Telescope Imaging Spectrograph failed, we find that the Lyα and Hα lines from shock emission continue to brighten, whereas their maximum velocities continue to decrease. We observe broad, blueshifted Lyα, which we attribute to resonant scattering of photons emitted from hot spots on the equatorial ring. We also detect N v λλ1239, 1243 angstrom line emission, but only to the red of Lyα. The profiles of the N v lines differ markedly from that of Hα, suggesting that the N4+ ions are scattered and accelerated by turbulent electromagnetic fields that isotropize the ions in the collisionless shock.

  7. Observing Supernova 1987A with the Refurbished Hubble Space Telescope

    CERN Document Server

    France, Kevin; Heng, Kevin; Kirshner, Robert; Challis, Peter; Bouchet, Patrice; Crotts, Arlin; Dwek, Eli; Fransson, Claes; Garnavich, Peter; Larsson, Josefin; Lawrence, Stephen; Lundqvist, Peter; Panagia, Nino; Pun, Chun; Smith, Nathan; Sollerman, Jesper; Sonneborn, George; Stocke, John; Wang, Lifan; Wheeler, Craig

    2010-01-01

    Observations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 using the refurbished instruments on HST with data taken in 2004, just before the Space Telescope Imaging Spectrograph failed, we find that the Ly-a and H-a lines from shock emission continue to brighten, while their maximum velocities continue to decrease. We observe broad blueshifted Ly-a, which we attribute to resonant scattering of photons emitted from hotspots on the equatorial ring. We also detect NV~\\lambda\\lambda 1239,1243 A line emission, but only to the red of Ly-A. The profiles of the NV lines differ markedly from that of H-a, suggesting that the N^{4+} ions are scattered and accelerated by turbulent electromagnetic fields that isotropize the ions in the collisionless shock.

  8. Hubble Space Telescope spectroscopy of OB stars in M31

    Science.gov (United States)

    Hutchings, J. B.; Bianchi, L.; Lamers, H. J. G. L. M.; Massey, P.; Morris, S. C.

    1992-01-01

    We have obtained UV spectra of two luminous hot stars in M31 with the Hubble Space Telescope. The stars are of late O and WN spectral type and lie on opposite sides of M31. We derive UV extinction curves for M31 which differ from both the Galaxy and the LMC. We find differences between the IS absorbers in both lines of sight in M31 and in the Galactic halo. The stellar wind-driven mass loss of the stars is found to be 10 times lower than in similar Galactic stars. One star appears to be an eclipsing W-R binary.

  9. HUBBLE SPACE TELESCOPE Photometry of the Globular Cluster M4

    Science.gov (United States)

    Ibata, Rodrigo A.; Richer, Harvey B.; Fahlman, Gregory G.; Bolte, Michael; Bond, Howard E.; Hesser, James E.; Pryor, Carlton; Stetson, Peter B.

    1999-02-01

    This paper presents a detailed description of the acquisition and processing of a large body of imaging data for three fields in the globular cluster M4 taken with the Wide Field and Planetary Camera 2 aboard the Hubble Space Telescope. Analysis with the ALLFRAME package yielded the deepest photometry yet obtained for this cluster. The resulting data set for 4708 stars (positions and calibrated photometry in V, I, and, in two fields, U) spanning approximately six cluster core radii is presented. The scientific analysis is deferred to three companion papers, which investigate the significant white dwarf population discovered and the main-sequence population.

  10. Teflon FEP Analyzed After Retrieval From the Hubble Space Telescope

    Science.gov (United States)

    Dever, Joyce A.; deGroh, Kim K.; Townsend, Jacqueline A.; Hansen, Patricia A.; Banks, Bruce A.; Wang, Len; He, Charles

    1999-01-01

    During the Hubble Space Telescope (HST) Second Servicing Mission, 6.8 years after the telescope was deployed in low Earth orbit, degradation of unsupported Teflon FEP (DuPont; fluorinated ethylene propylene), used as the outer layer of the multilayer insulation (MLI) blankets, was evident as large cracks on the telescope light shield. A sample of the degraded outer layer (see the photograph) was retrieved during the second servicing mission and returned to Earth for ground testing and evaluation. Also retrieved was a Teflon FEP radiator surface from a cryogen vent cover that was exposed to the space environment on the aft bulkhead of the HST. NASA Goddard Space Flight Center directed the efforts of the Hubble Space Telescope MLI Failure Review Board, whose goals included determining the FEP degradation mechanisms. As part of the investigations into the degradation mechanisms, specimens retrieved from the first and second HST servicing missions, 3.6 and 6.8 years after launch, respectively, were characterized through exhaustive mechanical, optical, and chemical testing. Testing led by Goddard included scanning electron microscopy, optical microscopy, tensile testing, solar absorptance measurements, time-of-flight secondary ion mass spectroscopy (TOF-SIMS), Fourier transform infrared microscopy (m-FTIR), attenuated total reflectance infrared microscopy (ATR/FTIR), and x-ray diffraction (XRD). The NASA Lewis Research Center contributed significantly to the analysis of the retrieved HST materials by leading efforts and providing results of bend testing, surface microhardness measurements, x-ray photoelectron spectroscopy, solid-state nuclear magnetic resonance spectroscopy, and density measurements. Other testing was conducted by Nano Instruments, Inc., and the University of Akron.

  11. Zero CTE Glass in the Hubble Space Telescope

    Science.gov (United States)

    Wood, H. John

    2008-01-01

    Orbiting high above the turbulence of the Earth's atmosphere, the Hubble Space Telescope (HST) has provided breathtaking views of astronomical objects never before seen in such detail. The steady diffraction-limited images allow this medium-size telescope to reach faint galaxies fainter than 30th stellar magnitude. Some of these galaxies are seen as early as 2 billion years after the Big Bang in a 13.7 billion year old universe. Up until recently, astronomers assumed that all of the laws of physics and astronomy applied back then as they do today. Now, using the discovery that certain supernovae are "standard candles," astronomers have found that the universe is expanding faster today than it was back then: the universe is accelerating in its expansion. The Hubble Space Telescope is a two-mirror Ritchey-Chretien telescope of 2.4m aperture in low earth orbit. The mirrors are made of Ultra Low Expansion (ULE) glass by Corning Glass Works. This material allows rapid figuring and outstanding performance in space astronomy applications. The paper describes how the primary mirror was mis-figured in manufacturing and later corrected in orbit. Outstanding astronomical images taken over the last 17 years show how the application of this new technology has advanced our knowledge of the universe. Not only has the acceleration of the expansion been discovered, the excellent imaging capability of HST has allowed gravitational lensing to become a tool to study the distribution of dark matter and dark energy in distant clusters of galaxies. The HST has touched practically every field of astronomy enabling astronomers to solve many long-standing puzzles. It will be a long time until the end of the universe when the density is near zero and all of the stars have long since evaporated. It is remarkable that humankind has found the technology and developed the ability to interpret the measurements in order to understand this dramatic age we live in.

  12. STS-31 Mission Onboard Photograph-Hubble Space Telescope

    Science.gov (United States)

    1990-01-01

    In this photograph, the Hubble Space Telescope (HST) was being deployed on April 25, 1990. The photograph was taken by the IMAX Cargo Bay Camera (ICBC) mounted in a container on the port side of the Space Shuttle orbiter Discovery (STS-31 mission). The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit for 15 years or more. The HST provides fine detail imaging, produces ultraviolet images and spectra, and detects very faint objects. Two months after its deployment in space, scientists detected a 2-micron spherical aberration in the primary mirror of the HST that affected the telescope's ability to focus faint light sources into a precise point. This imperfection was very slight, one-fiftieth of the width of a human hair. A scheduled Space Service servicing mission (STS-61) in 1993 permitted scientists to correct the problem. During four spacewalks, new instruments were installed into the HST that had optical corrections. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Cornecticut, developed the optical system and guidance sensors. Photo Credit: NASA/Smithsonian Institution/Lockheed Corporation.

  13. NASA's Hubble Space Telescope: Presentation to the Freedom Museum

    Science.gov (United States)

    Leete, Stephen

    2017-01-01

    The Freedom Museum, located in Manassas, VA, requested a speaker through the NASA Speakers Bureau, on the topic of the Hubble Space Telescope. A public outreach presentation has been prepared. Many of the facts are drawn from a public source, the Wikipedia article on the Hubble Space Telescope. This covers the history of the development of the HST, as well as the initial flaw and its repair, and the subsequent series of servicing missions, for which I was involved in the last three. This has been the topic of numerous books. This has been supplemented mostly by facts known to the author, such as names of individuals who played key roles, but not any technical information. Because the reqeustor asked for a significant part of the talk to address major science findings and discoveries, significant portions of a public presentation on this topic developed by Kenneth Carpenter of GSFC were obtained and incorporated, with credit. I have confirmed that this material is also available through public sources.

  14. The Hubble Space Telescope from concept to success

    CERN Document Server

    Shayler, David J

    2016-01-01

    The highly successful Hubble Space Telescope was meant to change our view and understanding of the universe. Within weeks of its launch in 1990, however, the space community was shocked to find out that the primary mirror of the telescope was flawed. It was only the skills of scientists and engineers on the ground and the daring talents of astronauts sent to service the telescope in December 1993 that saved the mission. For over two decades NASA had developed the capabilities to service a payload in orbit. This involved numerous studies and the creation of a ground-based infrastructure to support the challenging missions. Unique tools and EVA hardware supported the skills developed in crew training that then enabled astronauts to complete a demanding series of spacewalks. Drawing upon first hand interviews with those closely involved in the project over thirty years ago this story explains the development of the servicing mission concept and the hurdles that had to be overcome to not only launch the telescope...

  15. Feedback loops from the Hubble Space Telescope data processing system

    Science.gov (United States)

    Fraquelli, Dorothy A.; Arquilla, Richard; Ellis, Tracy; Hamilton, Forrest C.; Holm, Albert; Kochte, Mark

    2002-12-01

    This paper presents an overview of the history and technology by which tools placed in the Hubble Space Telescope (HST) data processing pipeline were used to feedback information on observation execution to the scheduling system and observers. Because the HST is in a relatively low orbit, which imposes a number of constraints upon its observations, it operates in a carefully planned, fully automated mode. To substitute for direct observer involvement available at most ground-based observatories and to provide rapid feedback on failures that might affect future visits, the Space Telescope Science Institute (STScI) gradually evolved a system for screening science and engineering products during pipeline processing. The highly flexible HST data processing system (OPUS) allows tools to be introduced to use the content of FITS keywords to alert production staff to potential telescope and instrument performance failures. Staff members review the flagged data and, if appropriate, notify the observer and the scheduling staff so that they can resolve the problems and possibly repeat the failed observations. This kind of feedback loop represents a case study for other automated data collection systems where rapid response to certain quantifiable events in the data is required. Observatory operations staff can install processes to look for these events either in the production pipeline or in an associated pipeline into which the appropriate data are piped. That process can then be used to notify scientists to evaluate the data and decide upon a response or to automatically initiate a response.

  16. A Hubble Space Telescope Snapshot Survey of Nearby Supernovae

    CERN Document Server

    Li, W; Van Dyk, S D; Hu, J; Qiu, Y; Modjaz, M; Leonard, D C; Li, Weidong; Filippenko, Alexei V.; Dyk, Schuyler D. Van; Hu, Jingyao; Qiu, Yulei; Modjaz, Maryam; Leonard, Douglas C.

    2002-01-01

    We present photometry of 12 recent supernovae (SNe) recovered in a {\\it Hubble Space Telescope} Snapshot program, and tie the measurements to earlier ground-based observations, in order to study the late-time evolution of the SNe. Many of the ground-based measurements are previously unpublished, and were made primarily with a robotic telescope, the Katzman Automatic Imaging Telescope. Evidence for circumstellar interaction is common among the core-collapse SNe. Late-time decline rates for Type IIn SNe are found to span a wide range, perhaps due to differences in circumstellar interaction. An extreme case, SN IIn 1995N, declined by only 1.2 mag in $V$ over about 4 years following discovery. Template images of some SNe must therefore be obtained many years after the explosion, if contamination from the SN itself is to be minimized. Evidence is found against a previous hypothesis that the Type IIn SN 1997bs was actually a superoutburst of a luminous blue variable star. The peculiar SN Ic 1997ef, a "hypernova," d...

  17. HUBBLE SPACE TELESCOPE Snapshot Survey of 3CR Quasars: The Data

    Science.gov (United States)

    Lehnert, Matthew D.; Miley, George K.; Sparks, William B.; Baum, Stefi A.; Biretta, John; Golombek, Daniel; de Koff, Sigrid; Macchetto, Ferdinando D.; McCarthy, Patrick J.

    1999-08-01

    We present images taken with the Wide Field Planetary Camera (WFPC-2) on the Hubble Space Telescope (HST) of 43 quasars selected from the 3CR radio catalog. The redshift range of the targets is large--0.3Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

  18. Hubble Space Telescope solar cell module thermal cycle test

    Science.gov (United States)

    Douglas, Alexander; Edge, Ted; Willowby, Douglas; Gerlach, Lothar

    1992-01-01

    The Hubble Space Telescope (HST) solar array consists of two identical double roll-out wings designed after the Hughes flexible roll-up solar array (FRUSA) and was developed by the European Space Agency (ESA) to meet specified HST power output requirements at the end of 2 years, with a functional lifetime of 5 years. The requirement that the HST solar array remain functional both mechanically and electrically during its 5-year lifetime meant that the array must withstand 30,000 low Earth orbit (LEO) thermal cycles between approximately +100 and -100 C. In order to evaluate the ability of the array to meet this requirement, an accelerated thermal cycle test in vacuum was conducted at NASA's Marshall Space Flight Center (MSFC), using two 128-cell solar array modules which duplicated the flight HST solar array. Several other tests were performed on the modules. The thermal cycle test was interrupted after 2,577 cycles, and a 'cold-roll' test was performed on one of the modules in order to evaluate the ability of the flight array to survive an emergency deployment during the dark (cold) portion of an orbit. A posttest static shadow test was performed on one of the modules in order to analyze temperature gradients across the module. Finally, current in-flight electrical performance data from the actual HST flight solar array will be tested.

  19. "Amazing Space": Creating Educational Resources from Current Scientific Research Results from the Hubble Space Telescope.

    Science.gov (United States)

    Christian, C. A.; Eisenhamer, B.; Eisenhamer, Jonathan; Teays, Terry

    2001-01-01

    Introduces the Amazing Space program which is designed to enhance student mathematics, science, and technology skills using recent data and results from the National Aeronautics and Space Administration's (NASA) Hubble Space Telescope mission. Explains the process of designing multi-media resources in a five-week summer workshop that partners…

  20. European astronomers' successes with the Hubble Space Telescope*

    Science.gov (United States)

    1997-02-01

    can bend the light from more distant objects, so magnifying and intensifying their images. In one spectacular case, cluster Abell 2218 creates in Hubble's WFPC2 camera more than a hundred images of galaxies lying beyond it. Without the magnifying effect of the cluster, many of these remote objects would be too faint to study in detail. Compared with man-made optics, the gravitational lenses are complex. They produce multiple images (as many as seven or more views of the same object) and they also smear the images into arcs. Team-member Jean-Paul Kneib, who is now at Toulouse, uses the distortions as a guide to distance. The more distorted the image, the farther off a galaxy is. The galaxies imaged by Abell 2218 are 5 to 8 billion light-years away, and Kneib's estimates have been confirmed by Tim Ebbels of Cambridge using the William Herschel Telescope located on the Spanish island of La Palma. Seen as they were early in the history of the Universe, the objects seem surprisingly similar to nearer and more mature galaxies. The cosmic scale Gustav Tammann of Basel and his collaborators use the Hubble Space Telescope to measure the Hubble Constant. Both are named after Edwin Hubble who discovered, almost 70 years ago, that the galaxies are spreading apart. The Hubble Constant is the rate of expansion -- and the most important number in cosmology, because it fixes the size and the maximum age of the observable Universe. Since the launch of the space telescope in 1990, two independent teams have tried to fix the constant but their answers disagree. A high expansion rate, which makes the Universe relatively young, is preferred by Wendy Freedman's team consisting largely of American astronomers. A lower value for Hubble's Constant, implying an older Universe, comes from a mainly European team led by the American astronomer Allan Sandage. Tammann belongs to the latter, "old Universe" camp and he is philosophical about the delay in reaching a consensus. "I've been waiting

  1. Observing Supernova 1987A with the Refurbished Hubble Space Telescope

    Science.gov (United States)

    France, Kevin; McCray, Richard; Heng, Kevin; Kirshner, Robert P.; Challis, Peter; Bouchet, Patrice; Crotts, Arlin; Dwek, Eli; Fransson, Claes; Garnavich, Peter M.; hide

    2010-01-01

    The young remnant of supernova 1987A (SN 1987A) offers an unprecedented glimpse into the hydrodynamics and kinetics of fast astrophysical shocks. We have been monitoring SN 1987A with the Hubble Space Telescope (HST) since it was launched. The recent repair of the Space Telescope Imaging Spectrograph (STIS) allows us to compare observations in 2004, just before its demise, with those in 2010, shortly after its resuscitation by NASA astronauts. We find that the Ly-alpha and H-alpha lines from shock emission continue to brighten, while their maximum velocities continue to decrease. We report evidence for nearly coherent, resonant scattering of Lya photons (to blueshifts approximately -12,000 km /s) from hotspots on the equatorial ring. We also report emission to the red of Ly-alpha that we attribute to N v lambda lambda 1239,1243 Angstrom line emission. These lines are detectable because, unlike hydrogen atoms, N4+ ions emit hundreds of photons before they are ionized. The profiles of the N v lines differ markedly from that of H-alpha. We attribute this to scattering of N4+ ions by magnetic fields in the ionized plasma. Thus, N v emission provides a unique probe of the isotropization zone of the collisionless shock. Observations with the recently installed Cosmic Origins Spectrograph (COS) will enable us to observe the N v lambda lambda 1239,1243 Angstrom line profiles with much higher signal-to-noise ratios than possible with STIS and may reveal lines of other highly ionized species (such as C IVlambda lambda 1548,1551 Angstrom) that will test our explanation for the N v emission

  2. Hubble Space Telescope Observations of the HD 202628 Debris Disk

    Science.gov (United States)

    Krist, John E.; Stapelfeldt, Karl R.; Bryden, Geoffrey; Plavchan, Peter

    2012-01-01

    A ring-shaped debris disk around the G2V star HD 202628 (d = 24.4 pc) was imaged in scattered light at visible wavelengths using the coronagraphic mode of the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. The ring is inclined by approx.64deg from face-on, based on the apparent major/minor axis ratio, with the major axis aligned along PA = 130deg. It has inner and outer radii (> 50% maximum surface brightness) of 139 AU and 193 AU in the northwest ansae and 161 AU and 223 AU in the southeast ((Delta)r/r approx. = 0.4). The maximum visible radial extent is approx. 254 AU. With a mean surface brightnesses of V approx. = 24 mag arcsec.(sup -2), this is the faintest debris disk observed to date in reflected light. The center of the ring appears offset from the star by approx.28 AU (deprojected). An ellipse fit to the inner edge has an eccentricity of 0.18 and a = 158 AU. This offset, along with the relatively sharp inner edge of the ring, suggests the influence of a planetary-mass companion. There is a strong similarity with the debris ring around Fomalhaut, though HD 202628 is a more mature star with an estimated age of about 2 Gyr. We also provide surface brightness limits for nine other stars in our study with strong Spitzer excesses around which no debris disks were detected in scattered light (HD 377, HD 7590, HD 38858, HD 45184, HD 73350, HD 135599, HD 145229, HD 187897, and HD 201219).

  3. Custom CMOS Reed Solomon coder for the Hubble Space Telescope

    Science.gov (United States)

    Whitaker, S.; Cameron, K.; Owsley, P.; Maki, G.

    1990-01-01

    A VLSI coder is presented that can function either as an encoder or decoder for Reed-Solomon codes. VLSI is one approach to implementing high-performance Reed-Solomon decoders. There are three VLSI technologies that could be used: gate arrays, standard cells, and full custom. The first two approaches are relatively easy to implement, but are limited in both performance and density. Full-custom VLSI is used to achieve both circuit density and speed, and allows control of the amount of interconnect. Speed, which is a function of capacitance, which is a function of interconnect, is an important parameter in high-performance VLSI. A single 8.2 mm x 8.4 mm, 200,000 transistor CMOS chip implementation of the Reed-Solomon code required by the Hubble Space Telescope is reported. The chip features a 10-MHz sustained byte rate independent of error pattern. The 1.6-micron CMOS integrated circuit has complete decoder and encoder functions and uses a single data/system clock. Block lengths up to 255 bytes and shortened codes are supported with no external buffering. Erasure corrections and random error corrections are supported with programmable correction of up to 10 symbol errors. Correction time is independent of error pattern and the number of errors in the incoming message.

  4. SHIELD: Distance Estimates from Hubble Space Telescope Imaging

    Science.gov (United States)

    Cave, Ian; Cannon, J. M.; Larson, E.; Marshall, M.; Moody, S.; Adams, E. A.; Dolphin, A. E.; Elson, E. C.; Giovanelli, R.; Haynes, M. P.; McQuinn, K. B.; Ott, J.; Saintonge, A.; Salzer, J. J.; Skillman, E. D.

    2013-01-01

    The Survey of HI in Extremely Low-mass Dwarfs (SHIELD) is an ongoing study of twelve galaxies with HI masses between 106 and 107 Solar masses, detected by the Arecibo Legacy Fast ALFA (ALFALFA) survey. Here we present new Hubble Space Telescope (HST) imaging of the SHIELD galaxies. The primary goal is to determine the distance of each galaxy. We apply two techniques to measure the apparent magnitude of the tip of the red giant branch (TRGB) feature in the HST color magnitude diagrams. First, a custom designed edge detection filter was written to determine the TRGB magnitude based on a user-selected region of the color magnitude diagram. Second, we apply the maximum likelihood technique implemented in the "TRGBtool" software package (Makarov et al. 2006). In addition to the distances based on the TRGB feature, we also use the MATCH software (Dolphin 2002) to determine the best-fit distance based on the overall CMD morphology. We compare these distance estimates for all members of the SHIELD galaxies, and present a final table of distances that is used in each of the companion SHIELD presentations.

  5. HUBBLE SPACE TELESCOPE View of the Heart of Ursa Minor

    Science.gov (United States)

    Battinelli, Paolo; Demers, Serge

    1999-04-01

    Hubble Space Telescope F606W observations to 26th magnitude are used to investigate the stellar distribution in the center of the Ursa Minor dwarf spheroidal galaxy. The central surface density is found to be low, less than 700 stars arcmin^-2, with no sign of a pronounced cusp. The maximum of the surface density is not found at our adopted center but in a ringlike structure some 13" from it. We identify this feature with the subclustering identified by Olszewski & Aaronson, who believed that it was off-center. The currently accepted King's structural parameters, r_c and r_t, of Ursa Minor are found to be unsuitable to represent the stellar surface density near the center. Our star counts are used to obtain a lower limit of the central stellar density without the use of the velocity dispersion. We find a lower limit of 1.7+/-1.1 M_solar pc^-3 from stars that were counted. By extrapolating the mass function to lower masses, we estimate that the true density could increase be a factor of 7.

  6. Hubble Space Telescope Astrometry of the Procyon System

    CERN Document Server

    Bond, Howard E; Schaefer, Gail H; Demarque, Pierre; Girard, Terrence M; Holberg, Jay B; Gudehus, Donald; Mason, Brian D; Kozhurina-Platais, Vera; Burleigh, Matthew R; Barstow, Martin A; Nelan, Edmund P

    2015-01-01

    The nearby star Procyon is a visual binary containing the F5 IV-V subgiant Procyon A, orbited in a 40.84 yr period by the faint DQZ white dwarf Procyon B. Using images obtained over two decades with the Hubble Space Telescope, and historical measurements back to the 19th century, we have determined precise orbital elements. Combined with measurements of the parallax and the motion of the A component, these elements yield dynamical masses of 1.478 +/- 0.012 Msun and 0.592 +/- 0.006 Msun for A and B, respectively. The mass of Procyon A agrees well with theoretical predictions based on asteroseismology and its temperature and luminosity. Use of a standard core-overshoot model agrees best for a surprisingly high amount of core overshoot. Under these modeling assumptions, Procyon A's age is ~2.7 Gyr. Procyon B's location in the H-R diagram is in excellent agreement with theoretical cooling tracks for white dwarfs of its dynamical mass. Its position in the mass-radius plane is also consistent with theory, assuming ...

  7. Interferometric Astrometry with Hubble Space Telescope - A Review

    Science.gov (United States)

    Benedict, G. F.; McArthur, B. E.; Franz, O. G.; Wasserman, L. H.; Henry, T. J.; Takato, T.; Strateva, I.

    2000-05-01

    We review recent results from fringe tracking (POS) and fringe scanning (TRANS) mode astrometry using Fine Guidance Sensor 3 aboard Hubble Space Telescope. The relatively large field of regard, faint limiting magnitude, and raw resolution of FGS 3 have allowed us to obtain sub-millisecond of arc precision parallaxes for several Cataclysmic Variables ( RW Tri & TV Col), a fundamental distance scale calibrator (RR Lyr), a Planetary Nebula central star (NGC 6853), and a hot White Dwarf binary (Feige 24). We have determined parallaxes, orbital parameters, and masses for low-mass binaries critical to the lower main sequence Mass-Luminosity Relationship (Gl 791.2, Wolf 1062, Gl 623). The Astrometry Science Team presently consists of W. H. Jefferys, P.I., G. F. Benedict, Deputy P.I., B. McArthur, O.G. Franz, L. H. Wasserman, L. W. Fredrick, W. van Altena, E. Nelan, R. Duncombe, P. J. Shelus, and P. D. Hemenway. This research had the support of NASA Grants NAS5-1603 (GSFC), and GO-06036.01-94A, GO-07491.01-97A (STScI).

  8. DEEP HUBBLE SPACE TELESCOPE IMAGING IN NGC 6397: STELLAR DYNAMICS

    Energy Technology Data Exchange (ETDEWEB)

    Heyl, J. S.; Richer, H.; Woodley, K. A. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1 (Canada); Anderson, J.; Dotter, A.; Kalirai, J. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Fahlman, G.; Stetson, P. [Herzberg Institute for Astrophysics, National Research Council, Victoria, BC (Canada); Hurley, J. [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122 (Australia); Rich, R. M. [Division of Astronomy, University of California, Los Angeles, CA 90095-1562 (United States); Shara, M.; Zurek, D. [American Museum of Natural History, New York, NY 10024-5192 (United States)

    2012-12-10

    Multi-epoch observations with the Advanced Camera for Surveys on the Hubble Space Telescope provide a unique and comprehensive probe of stellar dynamics within NGC 6397. We are able to confront analytic models of the globular cluster with the observed stellar proper motions. The measured proper motions probe well along the main sequence from 0.8 to below 0.1 M{sub Sun} as well as white dwarfs younger than 1 Gyr. The observed field lies just beyond the half-light radius where standard models of globular cluster dynamics (e.g., based on a lowered Maxwellian phase-space distribution) make very robust predictions for the stellar proper motions as a function of mass. The observed proper motions show no evidence for anisotropy in the velocity distribution; furthermore, the observations agree in detail with a straightforward model of the stellar distribution function. We do not find any evidence that the young white dwarfs have received a natal kick in contradiction with earlier results. Using the observed proper motions of the main-sequence stars, we obtain a kinematic estimate of the distance to NGC 6397 of 2.2{sup +0.5}{sub -0.7} kpc and a mass of the cluster of 1.1 {+-} 0.1 Multiplication-Sign 10{sup 5} M{sub Sun} at the photometric distance of 2.53 kpc. One of the main-sequence stars appears to travel on a trajectory that will escape the cluster, yielding an estimate of the evaporation timescale, over which the number of stars in the cluster decreases by a factor of e, of about 3 Gyr. The proper motions of the youngest white dwarfs appear to resemble those of the most massive main-sequence stars, providing the first direct constraint on the relaxation time of the stars in a globular cluster of greater than or about 0.7 Gyr.

  9. Astronomy from Space: The Hubble, Herschel and James Webb Space Telescopes

    Science.gov (United States)

    Gardner, Jonathan P.

    2009-01-01

    Space-based astronomy is going through a renaissance, with three Great Observatories currently flying: Hubble in the visible and ultraviolet, Spitzer in the infrared and Chandra in X-rays. The future looks equally bright. The final servicing mission to Hubble will take place in February 2009 and promises to make the observatory more capable than ever with two new cameras, and refurbishment that will allow it to last at least five years. The upcoming launch of the Herschel Space Telescope will open the far-infrared to explore the cool and dusty Universe. Finally, we look forward to the launch of the James Webb Space Telescope in 2013, which wil provide a successor to both Hubble and Spitzer. In this talk, the author discusses some of the highlights of scientific discovery in the last 10 years and reveals the promise to the next 10 years.

  10. Astronomy from Space: The Hubble, Herschel and James Webb Space Telescopes

    Science.gov (United States)

    Gardner, Jonathan P.

    2009-01-01

    Space-based astronomy is going through a renaissance, with three Great Observatories currently flying: Hubble in the visible and ultraviolet, Spitzer in the infrared and Chandra in X-rays. The future looks equally bright. The final servicing mission to Hubble will take place in February 2009 and promises to make the observatory more capable than ever with two new cameras, and refurbishment that will allow it to last at least five years. The upcoming launch of the Herschel Space Telescope will open the far-infrared to explore the cool and dusty Universe. Finally, we look forward to the launch of the James Webb Space Telescope in 2013, which wil provide a successor to both Hubble and Spitzer. In this talk, the author discusses some of the highlights of scientific discovery in the last 10 years and reveals the promise to the next 10 years.

  11. Thick Disks in the Hubble Space Telescope Frontier Fields

    Science.gov (United States)

    Elmegreen, Bruce G.; Elmegreen, Debra Meloy; Tompkins, Brittany; Jenks, Leah G.

    2017-09-01

    Thick disk evolution is studied using edge-on galaxies in two Hubble Space Telescope Frontier Field Parallels. The galaxies were separated into 72 clumpy types and 35 spiral types with bulges. Perpendicular light profiles in F435W, F606W, and F814W (B, V, and I) passbands were measured at 1 pixel intervals along the major axes and fitted to sech2 functions convolved with the instrument line spread function (LSF). The LSF was determined from the average point spread function of ∼20 stars in each passband and field, convolved with a line of uniform brightness to simulate disk blurring. A spread function for a clumpy disk was also used for comparison. The resulting scale heights were found to be proportional to galactic mass, with the average height for a 1010±0.5 M ⊙ galaxy at z = 2 ± 0.5 equal to 0.63 ± 0.24 kpc. This value is probably the result of a blend between thin and thick disk components that cannot be resolved. Evidence for such two-component structure is present in an inverse correlation between height and midplane surface brightness. Models suggest that the thick disk is observed best between the clumps, and there the average scale height is 1.06 ± 0.43 kpc for the same mass and redshift. A 0.63 ± 0.68 mag V ‑ I color differential with height is also evidence for a mixture of thin and thick components.

  12. Hubble Space Telescope Astrometry of the Procyon System

    Science.gov (United States)

    Bond, Howard E.; Gilliland, Ronald L.; Schaefer, Gail H.; Demarque, Pierre; Girard, Terrence M.; Holberg, Jay B.; Gudehus, Donald; Mason, Brian D.; Kozhurina-Platais, Vera; Burleigh, Matthew R.

    2015-01-01

    The nearby star Procyon is a visual binary containing the F5 IV-V subgiant Procyon A, orbited in a 40.84-year period by the faint DQZ white dwarf (WD) Procyon B. Using images obtained over two decades with the Hubble Space Telescope, and historical measurements back to the 19th century, we have determined precise orbital elements. Combined with measurements of the parallax and the motion of the A component, these elements yield dynamical masses of 1.478 plus or minus 0.012M and 0.592 plus or minus 0.006M for A and B, respectively. The mass of Procyon A agrees well with theoretical predictions based on asteroseismology and its temperature and luminosity. Use of a standard core-overshoot model agrees best for a surprisingly high amount of core overshoot. Under these modeling assumptions, Procyon A's age is approximately 2.7 Gyr. Procyon B's location in the H-R diagram is in excellent agreement with theoretical cooling tracks for WDs of its dynamical mass. Its position in the mass-radius plane is also consistent with theory, assuming a carbon-oxygen core and a helium-dominated atmosphere. Its progenitor's mass was 1.9-2.2M, depending on its amount of core overshoot. Several astrophysical puzzles remain. In the progenitor system, the stars at periastron were separated by only approximately AU, which might have led to tidal interactions and even mass transfer; yet there is no direct evidence that these have occurred. Moreover the orbital eccentricity has remained high (approximately 0.40). The mass of Procyon B is somewhat lower than anticipated from the initial-to-final-mass relation seen in open clusters. The presence of heavy elements in its atmosphere requires ongoing accretion, but the place of origin is uncertain.

  13. Distance determinations to shield galaxies from Hubble space telescope imaging

    Energy Technology Data Exchange (ETDEWEB)

    McQuinn, Kristen B. W.; Skillman, Evan D. [Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota, 116 Church Street, S.E., Minneapolis, MN 55455 (United States); Cannon, John M.; Cave, Ian [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Salzer, John J. [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States); Haynes, Martha P.; Adams, Elizabeth; Giovanelli, Riccardo [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Elson, Ed C. [Astrophysics, Cosmology and Gravity Centre (ACGC), Department of Astronomy, University of Cape Town, Private Bag X3, Rondebosch 7701 (South Africa); Ott, Juërgen [National Radio Astronomy Observatory, P.O. Box O, 1003 Lopezville Road, Socorro, NM 87801 (United States); Saintonge, Amélie, E-mail: kmcquinn@astro.umn.edu [Max-Planck-Institute for Astrophysics, D-85741 Garching (Germany)

    2014-04-10

    The Survey of H I in Extremely Low-mass Dwarf (SHIELD) galaxies is an ongoing multi-wavelength program to characterize the gas, star formation, and evolution in gas-rich, very low-mass galaxies. The galaxies were selected from the first ∼10% of the H I Arecibo Legacy Fast ALFA (ALFALFA) survey based on their inferred low H I mass and low baryonic mass, and all systems have recent star formation. Thus, the SHIELD sample probes the faint end of the galaxy luminosity function for star-forming galaxies. Here, we measure the distances to the 12 SHIELD galaxies to be between 5 and 12 Mpc by applying the tip of the red giant method to the resolved stellar populations imaged by the Hubble Space Telescope. Based on these distances, the H I masses in the sample range from 4 × 10{sup 6} to 6 × 10{sup 7} M {sub ☉}, with a median H I mass of 1 × 10{sup 7} M {sub ☉}. The tip of the red giant branch distances are up to 73% farther than flow-model estimates in the ALFALFA catalog. Because of the relatively large uncertainties of flow-model distances, we are biased toward selecting galaxies from the ALFALFA catalog where the flow model underestimates the true distances. The measured distances allow for an assessment of the native environments around the sample members. Five of the galaxies are part of the NGC 672 and NGC 784 groups, which together constitute a single structure. One galaxy is part of a larger linear ensemble of nine systems that stretches 1.6 Mpc from end to end. Three galaxies reside in regions with 1-9 neighbors, and four galaxies are truly isolated with no known system identified within a radius of 1 Mpc.

  14. HUBBLE SPACE TELESCOPE ASTROMETRY OF THE PROCYON SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Bond, Howard E. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Gilliland, Ronald L.; Kozhurina-Platais, Vera; Nelan, Edmund P. [Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States); Schaefer, Gail H. [The CHARA Array of Georgia State University, Mount Wilson Observatory, Mount Wilson, CA 91023 (United States); Demarque, Pierre; Girard, Terrence M. [Department of Astronomy, Yale University, Box 208101, New Haven, CT 06520 (United States); Holberg, Jay B. [Lunar and Planetary Laboratory, University of Arizona, 1541 E. University Blvd., Tucson, AZ 85721 (United States); Gudehus, Donald [Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30303 (United States); Mason, Brian D. [U.S. Naval Observatory, 3450 Massachusetts Ave., Washington, DC 20392 (United States); Burleigh, Matthew R.; Barstow, Martin A., E-mail: heb11@psu.edu [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom)

    2015-11-10

    The nearby star Procyon is a visual binary containing the F5 IV-V subgiant Procyon A, orbited in a 40.84-year period by the faint DQZ white dwarf (WD) Procyon B. Using images obtained over two decades with the Hubble Space Telescope, and historical measurements back to the 19th century, we have determined precise orbital elements. Combined with measurements of the parallax and the motion of the A component, these elements yield dynamical masses of 1.478 ± 0.012 M{sub ⊙} and 0.592 ± 0.006 M{sub ⊙} for A and B, respectively. The mass of Procyon A agrees well with theoretical predictions based on asteroseismology and its temperature and luminosity. Use of a standard core-overshoot model agrees best for a surprisingly high amount of core overshoot. Under these modeling assumptions, Procyon A’s age is ∼2.7 Gyr. Procyon B’s location in the H-R diagram is in excellent agreement with theoretical cooling tracks for WDs of its dynamical mass. Its position in the mass–radius plane is also consistent with theory, assuming a carbon–oxygen core and a helium-dominated atmosphere. Its progenitor’s mass was 1.9–2.2 M{sub ⊙}, depending on its amount of core overshoot. Several astrophysical puzzles remain. In the progenitor system, the stars at periastron were separated by only ∼5 AU, which might have led to tidal interactions and even mass transfer; yet there is no direct evidence that these have occurred. Moreover the orbital eccentricity has remained high (∼0.40). The mass of Procyon B is somewhat lower than anticipated from the initial-to-final-mass relation seen in open clusters. The presence of heavy elements in its atmosphere requires ongoing accretion, but the place of origin is uncertain.

  15. Hubble Space Telescope Astrometry of the Procyon System

    Science.gov (United States)

    Bond, Howard E.; Gilliland, Ronald L.; Schaefer, Gail H.; Demarque, Pierre; Girard, Terrence M.; Holberg, Jay B.; Gudehus, Donald; Mason, Brian D.; Kozhurina-Platais, Vera; Burleigh, Matthew R.

    2015-01-01

    The nearby star Procyon is a visual binary containing the F5 IV-V subgiant Procyon A, orbited in a 40.84-year period by the faint DQZ white dwarf (WD) Procyon B. Using images obtained over two decades with the Hubble Space Telescope, and historical measurements back to the 19th century, we have determined precise orbital elements. Combined with measurements of the parallax and the motion of the A component, these elements yield dynamical masses of 1.478 plus or minus 0.012M and 0.592 plus or minus 0.006M for A and B, respectively. The mass of Procyon A agrees well with theoretical predictions based on asteroseismology and its temperature and luminosity. Use of a standard core-overshoot model agrees best for a surprisingly high amount of core overshoot. Under these modeling assumptions, Procyon A's age is approximately 2.7 Gyr. Procyon B's location in the H-R diagram is in excellent agreement with theoretical cooling tracks for WDs of its dynamical mass. Its position in the mass-radius plane is also consistent with theory, assuming a carbon-oxygen core and a helium-dominated atmosphere. Its progenitor's mass was 1.9-2.2M, depending on its amount of core overshoot. Several astrophysical puzzles remain. In the progenitor system, the stars at periastron were separated by only approximately AU, which might have led to tidal interactions and even mass transfer; yet there is no direct evidence that these have occurred. Moreover the orbital eccentricity has remained high (approximately 0.40). The mass of Procyon B is somewhat lower than anticipated from the initial-to-final-mass relation seen in open clusters. The presence of heavy elements in its atmosphere requires ongoing accretion, but the place of origin is uncertain.

  16. Nuclei of nearby disk galaxies .1. A Hubble Space Telescope imaging survey

    NARCIS (Netherlands)

    Phillips, AC; Illingworth, GD; MacKenty, JW; Franx, M

    We present deconvolved images of the central regions of 20 nearby disk galaxies, obtained with the original Planetary Camera of the Hubble Space Telescope. The galaxies span a range in Hubble type from SO to Sm. We have measured surface brightness profiles, and inverted these to estimate

  17. Hubble Space Telescope NICMOS Polarization Measurements of OMC-1

    Science.gov (United States)

    Simpson, Janet P.; Colgan, Sean W. J.; Erickson, Edwin F.; Burton, Michael G.; Schultz, A. S. B.

    2006-01-01

    We present 2 micrometer polarization measurements of positions in the BN region of the Orion Molecular Cloud (OMC-1) made with NICMOS Camera 2 (0.2" resolution) on Hubble Space Telescope. Our goals are to seek the sources of heating for IRc2, 3, 4, and 7, identify possible young stellar objects (YSOs), and characterize the grain alignment in the dust clouds along the lines-of-sight to the stars. Our results are as follows: BN is approximately 29% polarized by dichroic absorption and appears to be the illuminating source for most of the nebulosity to its north and up to approximately 5" to its south. Although the stars are probably all polarized by dichroic absorption, there are a number of compact, but non-point-source, objects that could be polarized by a combination of both dichroic absorption and local scattering of star light. We identify several candidate YSOs, including an approximately edge-on bipolar YSO 8.7" east of BN, and a deeply-embedded IRc7, all of which are obviously self-luminous at mid-infrared wavelengths and may be YSOs. None of these is a reflection nebula illuminated by a star located near radio source I, as was previously suggested. Other IRc sources are clearly reflection nebulae: IRc3 appears to be illuminated by IRc2-B or a combination of the IRc2 sources, and IRc4 and IRc5 appear to be illuminated by an unseen star in the vicinity of radio source I, or by Star n or IRc2-A. Trends in the magnetic field direction are inferred from the polarization of the 26 stars that are bright enough to be seen as NICMOS point sources. Their polarization ranges from N less than or equal to 1% (all stars with this low polarization are optically visible) to greater than 40%. The most polarized star has a polarization position angle different from its neighbors by approximately 40 degrees, but in agreement with the grain alignment inferred from millimeter polarization measurements of the cold dust cloud in the southern part of OMC-1. The polarization

  18. Experience with the Hubble Space Telescope: 20 years of an archetype

    CERN Document Server

    Lallo, Matthew

    2012-01-01

    The Hubble Space Telescope's mission is summarized, with special emphasis placed on the Space Telescope Science Institute's unique experience with Hubble's behavior as an astronomical telescope in the environment of low earth orbit for over two decades. Historical context and background are given, and the project's early scientific expectations are described. A general overview of the spacecraft is followed by a more detailed look at the optical design, both as intended and as built. Basic characteristics of the complete complement of science instruments are also summarized. Experience with the telescope on-orbit is reviewed, starting with the major initial problems, solutions, human servicing missions, and the associated expansion of the observatory's capabilities over this time. Specific attention is then given to understanding Hubble's optical quality and pointing/jitter performance, two fundamental characteristics of a telescope. Experience with-and the important mitigation of-radiation damage and contami...

  19. Reliability and maintenance simulation of the Hubble Space Telescope

    Science.gov (United States)

    Pizzano, F.

    1986-01-01

    An analytical approach is presented which was developed and implemented at MSFC specifically for the Space Telescope Program to provide comparisons of critical item failures, system downstates, on-orbit servicing versus return for ground maintenance, overall system downtime, and to obtain a measure of expected uptime for science functions.

  20. Eyes on the Universe: The Legacy of the Hubble Space Telescope and Looking to the Future with the James Webb Space Telescope

    Science.gov (United States)

    Straughn, Amber

    2011-01-01

    Over the past 20 years the Hubble Space Telescope has revolutionized our understanding of the Universe. Most recently, the complete refurbishment of Hubble in 2009 has given new life to the telescope and the new science instruments have already produced groundbreaking science results, revealing some of the most distant galaxy candidates ever discovered. Despite the remarkable advances in astrophysics that Hubble has provided, the new questions that have arisen demand a new space telescope with new technologies and capabilities. I will present the exciting new technology development and science goals of NASA's James Webb Space Telescope, which is currently being built and tested and will be launched this decade.

  1. Finding our Origins with the Hubble and James Webb Space Telescopes

    Science.gov (United States)

    Gardner, Jonathan P.

    2009-01-01

    NASA is planning a successor to the Hubble Space Telescope designed to study the origins of galaxies, stars, planets and life in the universe. In this talk, Dr. Gardner will discuss the origin and evolution of galaxies, beginning with the Big Bang and tracing what we have learned with Hubble through to the present day. He will show that results from studies with Hubble have led to plans for its successor, the James Webb Space Telescope. Webb is scheduled to launch in 2014, and is designed to find the first galaxies that formed in the distant past and to penetrate the dusty clouds of gas where stars are still forming today. He will compare Webb to Hubble, and discuss recent progress in the construction of the observatory.

  2. Hubble Space Telescope mock-up in use in the MDF

    Science.gov (United States)

    1986-01-01

    View of helium filled mock-up of the Hubble Space Telescope in use in the Manipulator Development Facility (MDF) in bldg 9A. The mock-up is being maneuvered on the end of the remote manipulator system (RMS) arm. The Space Shuttle full fuselage trainer is seen in the background, to the left.

  3. Hubble Space Telescope - Scientific, Technological and Social Contributions to the Public Discourse on Science

    Science.gov (United States)

    Wiseman, Jennifer

    2012-01-01

    The Hubble Space Telescope has unified the world with a sense of awe and wonder for 2 I years and is currently more scientifically powerful than ever. I will present highlights of discoveries made with the Hubble Space Telescope, including details of planetary weather, star formation, extra-solar planets, colliding galaxies, and a universe expanding with the acceleration of dark energy. I will also present the unique technical challenges and triumphs of this phenomenal observatory, and discuss how our discoveries in the cosmos affect our sense of human unity, significance, and wonder.

  4. Astrometry with Hubble Space Telescope Fine Guidance Sensors—A Review

    Science.gov (United States)

    Benedict, G. Fritz; McArthur, Barbara E.; Nelan, Edmund P.; Harrison, Thomas E.

    2017-01-01

    Over the last 20 years, Hubble Space Telescope Fine Guidance Sensor interferometric astrometry has produced precise and accurate parallaxes of astrophysical interesting stars and mass estimates for stellar companions. We review parallax results, and binary star and exoplanet mass determinations, and compare a subset of these parallaxes with preliminary {Gaia} results. The approach to single-field relative astrometry described herein may continue to have value for targets fainter than the {Gaia} limit in the coming era of 20-30 m telescopes. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

  5. Hubble Space Telescope NICMOS observations of the host galaxies of powerful radio sources : Does size matter?

    NARCIS (Netherlands)

    de Vries, WH; O'Dea, CP; Barthel, PD; Fanti, C; Fanti, R; Lehnert, MD

    2000-01-01

    We present near-infrared J- and K-band imaging of a sample of powerful radio source host galaxies with the Hubble Space Telescope NICMOS2 camera. These sources have been selected on their double-lobed radio structure and include a wide range of projected radio source sizes. The largest projected

  6. Legacy Extragalactic UV Survey (LEGUS) With the Hubble Space Telescope. I. Survey Description

    NARCIS (Netherlands)

    Calzetti, D.; Lee, J.C.; Sabbi, E.; Adamo, A.; Smith, L.J.; Andrews, J.E.; Ubeda, L.; Bright, S.N.; Thilker, D.; Aloisi, A.; Brown, T.M.; Chandar, R.; Christian, C.; Cignoni, M.; Clayton, G.C.; da Silva, R.; de Mink, S.E.; Dobbs, C.; Elmegreen, B.G.; Elmegreen, D.M.; Evans, A.S.; Fumagalli, M.; Gallagher III, J.S.; Gouliermis, D.A.; Grebel, E.K.; Herrero, A.; Hunter, D.A.; Johnson, K.E.; Kennicutt, R.C.; Kim, H.; Krumholz, M.R.; Lennon, D.; Levay, K.; Martin, C.; Nair, P.; Nota, A.; Östlin, G.; Pellerin, A.; Prieto, J.; Regan, M.W.; Ryon, J.E.; Schaerer, D.; Schiminovich, D.; Tosi, M.; Van Dyk, S.D.; Walterbos, R.; Whitmore, B.C.; Wofford, A.

    2015-01-01

    The Legacy ExtraGalactic UV Survey (LEGUS) is a Cycle 21 Treasury program on the Hubble Space Telescope aimed at the investigation of star formation and its relation with galactic environment in nearby galaxies, from the scales of individual stars to those of ~kiloparsec-size clustered structures.

  7. 25+ Years of the Hubble Space Telescope and a Simple Error that Cost Millions

    Science.gov (United States)

    Shakerin, Said

    2016-11-01

    A simple mistake in properly setting up a measuring device caused millions of dollars to be spent in correcting the initial optical failure of the Hubble Space Telescope (HST). This short article is intended as a lesson for a physics laboratory and discussion of errors in measurement.

  8. Hubble Space Telescope Ultraviolet spectroscopy of 14 low-redshift quasars

    NARCIS (Netherlands)

    Ganguly, R.; Kaastra, J.S.

    2007-01-01

    We present low-resolution ultraviolet spectra of 14 low-redshift quasars observed with the Hubble Space Telescope STIS as part of a Snapshot project to understand the relationship between quasar outflows and luminosity. The quasar is radio-loud but has a steep spectral index and a lobe-dominated

  9. A guide to hubble space telescope objects their selection, location, and significance

    CERN Document Server

    Chen, James L

    2015-01-01

    From the authors of "How to Find the Apollo Landing Sites," this is a guide to connecting the view above with the history of recent scientific discoveries from the Hubble Space Telescope. Each selected HST photo is shown with a sky map and a photograph or drawing to illustrate where to find it and how it should appear from a backyard telescope. Here is the casual observer's chance to locate the deep space objects visually, and appreciate the historic Hubble photos in comparison to what is visible from a backyard telescope. HST objects of all types are addressed, from Messier objects, Caldwell objects, and NGC objects, and are arranged in terms of what can be seen during the seasons. Additionally, the reader is given an historical perspective on the work of Edwin Hubble, while locating and viewing the deep space objects that changed astronomy forever.  Countless people have seen the amazing photographs taken by the Hubble Space Telescope. But how many people can actually point out where in the sky ...

  10. Legacy Extragalactic UV Survey (LEGUS) With the Hubble Space Telescope. I. Survey Description

    NARCIS (Netherlands)

    Calzetti, D.; Lee, J.C.; Sabbi, E.; Adamo, A.; Smith, L.J.; Andrews, J.E.; Ubeda, L.; Bright, S.N.; Thilker, D.; Aloisi, A.; Brown, T.M.; Chandar, R.; Christian, C.; Cignoni, M.; Clayton, G.C.; da Silva, R.; de Mink, S.E.; Dobbs, C.; Elmegreen, B.G.; Elmegreen, D.M.; Evans, A.S.; Fumagalli, M.; Gallagher III, J.S.; Gouliermis, D.A.; Grebel, E.K.; Herrero, A.; Hunter, D.A.; Johnson, K.E.; Kennicutt, R.C.; Kim, H.; Krumholz, M.R.; Lennon, D.; Levay, K.; Martin, C.; Nair, P.; Nota, A.; Östlin, G.; Pellerin, A.; Prieto, J.; Regan, M.W.; Ryon, J.E.; Schaerer, D.; Schiminovich, D.; Tosi, M.; Van Dyk, S.D.; Walterbos, R.; Whitmore, B.C.; Wofford, A.

    2015-01-01

    The Legacy ExtraGalactic UV Survey (LEGUS) is a Cycle 21 Treasury program on the Hubble Space Telescope aimed at the investigation of star formation and its relation with galactic environment in nearby galaxies, from the scales of individual stars to those of ~kiloparsec-size clustered structures. F

  11. Weak lensing analysis of C1 1358+62 using Hubble Space Telescope observations

    NARCIS (Netherlands)

    Hoekstra, H; Franx, M; Kuijken, K; Squires, G

    1998-01-01

    We report on the detection of weak gravitational lensing of faint, distant background objects by Cl 1358+62, a rich cluster of galaxies at a redshift of z = 0.33. The observations consist of a large, multicolor mosaic of Hubble Space Telescope WFPC2 images. The number density of approximately 50 bac

  12. WFIRST-AFTA Coronagraphic Operations: Lessons Learned from the Hubble Space Telescope and the James Webb Space Telescope

    CERN Document Server

    Debes, John H; Choquet, Elodie; Hines, Dean C; Perrin, Marshall; Golimowski, David A; Lajoie, Charles-Phillipe; Mazoyer, Johan; Pueyo, Laurent; Soummer, Remi; van der Marel, Roeland

    2015-01-01

    The coronagraphic instrument currently proposed for the WFIRST-AFTA mission will be the first example of a space-based coronagraph optimized for extremely high contrasts that are required for the direct imaging of exoplanets reflecting the light of their host star. While the design of this instrument is still in progress, this early stage of development is a particularly beneficial time to consider the operation of such an instrument. In this paper, we review current or planned operations on the Hubble Space Telescope (HST) and the James Webb Space Telescope (JWST) with a focus on which operational aspects will have relevance to the planned WFIRST-AFTA coronagraphic instrument. We identify five key aspects of operations that will require attention: 1) detector health and evolution, 2) wavefront control, 3) observing strategies/post-processing, 4) astrometric precision/target acquisition, and 5) polarimetry. We make suggestions on a path forward for each of these items.

  13. Servicing Mission 4 and the Extraordinary Science of the Hubble Space Telescope

    Science.gov (United States)

    Wiseman, Jennifer J.

    2012-01-01

    Just two years ago, NASA astronauts performed a challenging and flawless final Space Shuttle servicing mission to the orbiting Hubble Space Telescope. With science instruments repaired on board and two new ones installed, the observatory. is more powerful now than ever before. I will show the dramatic highlights of the servicing mission and present some of the early scientific results from the refurbished telescope. Its high sensitivity and multi-wavelength capabilities are revealing the highest redshift galaxies ever seen, as well as details of the cosmic web of intergalactic medium, large scale structure formation, solar system bodies, and stellar evolution. Enlightening studies of dark matter, dark energy, and exoplanet atmospheres add to the profound contributions to astrophysics that are being made with Hubble, setting a critical stage for future observatories such as the James Webb Space Telescope.

  14. Asteroseismology of the Transiting Exoplanet Host HD 17156 with Hubble Space Telescope Fine Guidance Sensor

    DEFF Research Database (Denmark)

    Gilliland, Ronald L.; McCullough, Peter R.; Nelan, Edmund P.

    2011-01-01

    Observations conducted with the Fine Guidance Sensor on the Hubble Space Telescope (HST) providing high cadence and precision time-series photometry were obtained over 10 consecutive days in 2008 December on the host star of the transiting exoplanet HD 17156b. During this time, 1.0 × 1012 photons...... light curve. Using the density constraint from asteroseismology, and stellar evolution modeling results in M * = 1.285 ± 0.026 M sun, R * = 1.507 ± 0.012 R sun, and a stellar age of 3.2 ± 0.3 Gyr. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science...

  15. Absolute Flux Calibration of the IRAC Instrument on the Spitzer Space Telescope using Hubble Space Telescope Flux Standards

    CERN Document Server

    Bohlin, R C; Rieke, G H; Ardila, D; Carey, S; Deustua, S; Engelbracht, C; Ferguson, H C; Flanagan, K; Kalirai, J; Meixner, M; Noriega-Crespo, A; Su, K Y L; Tremblay, P -E

    2011-01-01

    The absolute flux calibration of the James Webb Space Telescope will be based on a set of stars observed by the Hubble and Spitzer Space Telescopes. In order to cross-calibrate the two facilities, several A, G, and white dwarf (WD) stars are observed with both Spitzer and Hubble and are the prototypes for a set of JWST calibration standards. The flux calibration constants for the four Spitzer IRAC bands 1-4 are derived from these stars and are 2.3, 1.9, 2.0, and 0.5% lower than the official cold-mission IRAC calibration of Reach et al. (2005), i.e. in agreement within their estimated errors of ~2%. The causes of these differences lie primarily in the IRAC data reduction and secondarily in the SEDs of our standard stars. The independent IRAC 8 micron band-4 fluxes of Rieke et al. (2008) are about 1.5 +/- 2% higher than those of Reach et al. and are also in agreement with our 8 micron result.

  16. The Hubble Space Telescope: UV, Visible, and Near-Infrared Pursuits

    Science.gov (United States)

    Wiseman, Jennifer

    2010-01-01

    The Hubble Space Telescope continues to push the limits on world-class astrophysics. Cameras including the Advanced Camera for Surveys and the new panchromatic Wide Field Camera 3 which was installed nu last year's successful servicing mission S2N4,o{fer imaging from near-infrared through ultraviolet wavelengths. Spectroscopic studies of sources from black holes to exoplanet atmospheres are making great advances through the versatile use of STIS, the Space Telescope Imaging Spectrograph. The new Cosmic Origins Spectrograph, also installed last year, is the most sensitive UV spectrograph to fly io space and is uniquely suited to address particular scientific questions on galaxy halos, the intergalactic medium, and the cosmic web. With these outstanding capabilities on HST come complex needs for laboratory astrophysics support including atomic and line identification data. I will provide an overview of Hubble's current capabilities and the scientific programs and goals that particularly benefit from the studies of laboratory astrophysics.

  17. Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

    OpenAIRE

    Wang, Xiaofeng; Wang, Lifan; Filippenko, Alexei V.; Baron, Eddie; Kromer, Markus; Jack, Dennis; Zhang, Tianmeng,; Aldering, Greg; Antilogus, Pierre; Arnett, David; Baade, Dietrich; Barris, Brian J.; Benetti, Stefano; Bouchet, Patrice; Burrows, Adam S.

    2011-01-01

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This dataset provides unique spectral time series down to 2000 Angstrom. Significant diversity is seen in the near maximum-light spectra (~ 2000--3500 Angstrom) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Te...

  18. Technicians complete assembly of Hubble Space Telescope (HST) mockup at JSC

    Science.gov (United States)

    1989-01-01

    A technician listens to instructions as he operates the controls for the overhead crane that is lifting one of the Hubble Space Telescope (HST) high gain antennas (HGAs) into place on the HST Support System Module (SSM) forward shell. Others in a cherry picker basket wait to install the HGA on the SSM mockup. The HST mockup will be used for astronaut training and is being assembled in JSC's Mockup and Integration Laboratory (MAIL) Bldg 9A.

  19. Hubble Space Telescope Imaging of the Expanding Nebular Remnant of the 2006 Outburst of RS Ophiuchi

    CERN Document Server

    Harman, D J; Darnley, M J; O'Brien, T J; Bond, H E; Starrfield, S; Evans, A; Eyres, S P S; Ribeiro, V A R M; Echevarria, J M

    2008-01-01

    We report {\\it Hubble Space Telescope} imaging obtained 155 days and 449 days after the 2006 outburst of RS Ophiuchi. Both epochs show evidence of extended emission, consistent with that seen in earlier radio observations, and a maximum expansion rate of $3200\\pm300$ km s$^{-1}$ (in the plane of the sky). The extended structure is consistent with the remnant having a bipolar morphology with an inclination similar to that determined for the binary.

  20. Deep Hubble Space Telescope imaging of IC 1613. II. The star formation history

    NARCIS (Netherlands)

    Skillman, ED; Tolstoy, E; Cole, AA; Dolphin, AE; Saha, A; Gallagher, JS; Dohm-Palmer, RC; Mateo, M

    2003-01-01

    We have taken deep images of an outlying field in the Local Group dwarf irregular galaxy IC 1613 with the WFPC2 aboard the Hubble Space Telescope in the standard broadband F555W (V, 8 orbits) and F814W (I,16 orbits) filters. The photometry reaches to V=27.7 (M-V=+3.4) and I=27.1 (M-I=+2.8) at the 50

  1. Cameras a Million Miles Apart: Stereoscopic Imaging Potential with the Hubble and James Webb Space Telescopes

    CERN Document Server

    Green, Joel D; Stansberry, John A; Meinke, Bonnie

    2016-01-01

    The two most powerful optical/IR telescopes in history -- NASA's Hubble and James Webb Space Telescopes -- will be in space at the same time. We have a unique opportunity to leverage the 1.5 million kilometer separation between the two telescopic nodal points to obtain simultaneously captured stereoscopic images of asteroids, comets, moons and planets in our Solar System. Given the recent resurgence in stereo-3D movies and the recent emergence of VR-enabled mobile devices, these stereoscopic images provide a unique opportunity to engage the public with unprecedented views of various Solar System objects. Here, we present the technical requirements for acquiring stereoscopic images of Solar System objects, given the constraints of the telescopic equipment and the orbits of the target objects, and we present a handful of examples.

  2. Analyses of Hubble Space Telescope Aluminized-Teflon Insulation Retrieved After 19 Years of Space Exposure

    Science.gov (United States)

    deGroh, Kim K.; Waters, Deborah L.; Mohammed, Jelila S.; Perry, Bruce A.; Banks, Bruce A.

    2012-01-01

    Since its launch in April 1990, the Hubble Space Telescope (HST) has made many important observations from its vantage point in low Earth orbit (LEO). However, as seen during five servicing missions, the outer layer of multilayer insulation (MLI) has become successively more embrittled and has cracked in many areas. In May 2009, during the 5th servicing mission (called SM4), two MLI blankets were replaced with new insulation pieces and the space-exposed MLI blankets were retrieved for degradation analyses by teams at NASA Glenn Research Center (GRC) and NASA Goddard Space Flight Center (GSFC). The MLI blankets were from Equipment Bay 8, which received direct sunlight, and Equipment Bay 5, which received grazing sunlight. Each blanket contained a range of unique regions based on environmental exposure and/or physical appearance. The retrieved MLI blanket s aluminized-Teflon (DuPont) fluorinated ethylene propylene (Al-FEP) outer layers have been analyzed for changes in optical, physical, and mechanical properties, along with space induced chemical and morphological changes. When compared to pristine material, the analyses have shown how the Al-FEP was severely affected by the space environment. This paper reviews tensile properties, solar absorptance, thermal emittance, x-ray photoelectron spectroscopy (XPS) data and atomic oxygen erosion values of the retrieved HST blankets after 19 years of space exposure.

  3. An Atlas of Hubble Space Telescope Spectra and Images of Nearby Spiral Galaxies

    Science.gov (United States)

    Hughes, M. A.; Alonso-Herrero, A.; Axon, D.; Scarlata, C.; Atkinson, J.; Batcheldor, D.; Binney, J.; Capetti, A.; Carollo, C. M.; Dressel, L.; Gerssen, J.; Macchetto, D.; Maciejewski, W.; Marconi, A.; Merrifield, M.; Ruiz, M.; Sparks, W.; Stiavelli, M.; Tsvetanov, Z.; van der Marel, R.

    2003-08-01

    We have observed 54 nearby spiral galaxies with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope to obtain optical long-slit spectra of nuclear gas disks and STIS optical (~R band) images of the central 5''×5'' of the galaxies. These spectra are being used to determine the velocity field of nuclear disks and hence to detect the presence of central massive black holes. Here we present the spectra for the successful observations. Dust obscuration can be significant at optical wavelengths, and so we also combine the STIS images with archival Near-Infrared Camera and Multi-Object Spectrometer H-band images to produce color maps to investigate the morphology of gas and dust in the central regions. We find a great variety in the different morphologies, from smooth distributions to well-defined nuclear spirals and dust lanes. Based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

  4. STS-31 Hubble Space Telescope (HST) solar array (SA) mockup at MSFC, Alabama

    Science.gov (United States)

    1990-01-01

    A close-up shot shows an extravehicular mobility unit (EMU)-suited astronaut inspecting a solar array (SA) on the Hubble Space Telescope (HST) mockup in the Neutral Buoyancy Simulator (NBS) at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama. MSFC managed the design and development of the telescope. The weightlessness simulator was used to practice SA contingency procedures that might be used in space. Astronauts also practiced SA servicing missions in the simulator which they will perform on the telescope in space. The solar arrays which supply electrical power to the space telescope were developed and contributed by the European Space Agency (ESA). ESA's two prime contractors were British Aerospace in England and AEG in West Germany. The two wing-like solar arrays contain 48,000 solar cells. They convert the sun's energy to electricity during that portion of an orbit when they are exposed to sunlight. The power is stored in six batteries to support the telescope during

  5. Perkinelmer Lamda 950 Measurements in Support of Nasa's Hubble Space Telescope

    Science.gov (United States)

    Miller, Kevin H.; Quijada, Manuel A.

    2014-01-01

    We present visible spectroscopy measurements using the PerkinElmer Lambda 950 grating monochromator in support of two projects at NASA Goddard Space Flight Center. The first and primary project to be discussed is the Wide Field Planetary Camera 2 as an upgrade to the Hubble Space Telescope. Numerous optical filters were measured in the visible and near-infrared regions to experimentally vet the theoretical prediction upon which the filters were engineered. The second topic of our presentation will cover the measurement of SNAP prototype filters from three venders (ASAHI, BARR and JDSU) with applications towards NASAs the Joint Dark Energy Mission (JDEM).

  6. Micrometeoroid Impacts on the Hubble Space Telescope Wide Field and Planetary Camera 2: Larger Particles

    Science.gov (United States)

    Kearsley, A. T.; Grime, G. W.; Webb, R. P.; Jeynes, C.; Palitsin, V.; Colaux, J. L.; Ross, D. K.; Anz-Meador, P.; Liou, J. C.; Opiela, J.; hide

    2014-01-01

    The Wide Field and Planetary Camera 2 (WFPC2) was returned from the Hubble Space Telescope (HST) by shuttle mission STS-125 in 2009. In space for 16 years, the surface accumulated hundreds of impact features on the zinc orthotitanate paint, some penetrating through into underlying metal. Larger impacts were seen in photographs taken from within the shuttle orbiter during service missions, with spallation of paint in areas reaching 1.6 cm across, exposing alloy beneath. Here we describe larger impact shapes, the analysis of impactor composition, and the micrometeoroid (MM) types responsible.

  7. Hot Star Extension to the Hubble Space Telescope Stellar Spectral Library

    Science.gov (United States)

    Khan, Islam; Worthey, Guy

    2017-01-01

    CCD spectra of 36 stars were obtained from the Space Telescope Imaging Spectrograph (STIS) installed in the Hubble Space Telescope (HST) using three low resolution gratings - G230LB, G430L, and G750L, combined in processing to make single, continuous spectra from 0.2 to 1.0 micrometers. These spectra will be added to the Next Generation Stellar Library (NGSL) after completing the data analysis, reduction, and the required corrections. The stars include normal O-type stars, helium-burning stars, and post-asymptotic giant branch (PAGB) stars. Difficult steps in the data reduction process were removing the cosmic rays from the raw images and defringing of the G750L spectra using fringe flats. Most stars have detectable dust extinction. To aid in analysis, synthetic spectra were generated with various effective temperatures and surface gravities. A five parameter analytic model for the dust extinction correction was adopted. The parameters were varied in order to fit especially the ultraviolet portion of the observed and comparison synthetic spectra. Cross-correlation was used to bring the spectra to a common, final, zero velocity wavelength scale. Some star temperatures obtained from fitting synthetic versus observed spectra vary significantly from literature values. The dust extinction correction parameters also varied for several stars, mostly O stars, indicating variations in dust properties for different lines of sight. Analysis of scattered light effects showed that it was significant only for our two coolest stars.Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555.Support for this work was provided by NASA through grant number HST-GO-14141 from the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.

  8. Studying Galaxy Formation with the Hubble, Spitzer and James Webb Space Telescopes

    Science.gov (United States)

    Gardner, Jonathan P.

    2009-01-01

    The deepest optical to infrared observations of the universe include the Hubble Deep Fields, the Great Observatories Origins Deep Survey and the recent Hubble Ultra-Deep Field. Galaxies are seen in these surveys at redshifts z greater than 6, less than 1 Gyr after the Big Bang, at the end of a period when light from the galaxies has reionized Hydrogen in the inter-galactic medium. These observations, combined with theoretical understanding, indicate that the first stars and galaxies formed at z greater than 10, beyond the reach of the Hubble and Spitzer Space Telescopes. To observe the first galaxies, NASA is planning the James Webb Space Telescope (JWST), a large (6.5m), cold (less than 50K), infrared-optimized observatory to be launched early in the next decade into orbit around the second Earth-Sun Lagrange point. JWST will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. In addition to JWST's ability to study the formation and evolution of galaxies, I will also briefly review its expected contributions to studies of the formation of stars and planetary systems, and discuss recent progress in constructing the observatory.

  9. Hubble Space Telescope Deep Field Lesson Package. Teacher's Guide, Grades 6-8. Amazing Space: Education On-Line from the Hubble Space Telescope.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    This lesson guide accompanies the Hubble Deep Field set of 10 lithographs and introduces 4 astronomy lesson plans for middle school students. Lessons include: (1) "How Many Objects Are There?"; (2) "Classifying and Identifying"; (3) "Estimating Distances in Space"; and (4) "Review and Assessment." Appendices…

  10. Comparing Dawn, Hubble Space Telescope, and Ground-Based Interpretations of (4) Vesta

    CERN Document Server

    Reddy, Vishnu; Corre, Lucille Le; Scully, Jennifer E C; Gaskell, Robert; Russell, Christopher T; Park, Ryan S; Nathues, Andreas; Raymond, Carol; Gaffey, Michael J; Sierks, Holger; Becker, Kris J; McFadden, Lucy A

    2013-01-01

    Observations of asteroid 4 Vesta by NASA's Dawn spacecraft are interesting because its surface has the largest range of albedo, color and composition of any other asteroid visited by spacecraft to date. These hemispherical and rotational variations in surface brightness and composition have been attributed to impact processes since Vesta's formation. Prior to Dawn's arrival at Vesta, its surface properties were the focus of intense telescopic investigations for nearly a hundred years. Ground-based photometric and spectroscopic observations first revealed these variations followed later by those using Hubble Space Telescope. Here we compare interpretations of Vesta's rotation period, pole, albedo, topographic, color, and compositional properties from ground-based telescopes and HST with those from Dawn. Rotational spectral variations observed from ground-based studies are also consistent with those observed by Dawn. While the interpretation of some of these features was tenuous from past data, the interpretati...

  11. How Long Can the Hubble Space Telescope Operate Reliably? A Total Dose Perspective

    Science.gov (United States)

    Xapsos, M. A.; Stauffer, C.; Jordan, T.; Poivey, C.; Haskins, D. N.; Lum, G.; Pergosky, A. M.; Smith, D. C.; LaBel, K. A.

    2014-01-01

    The Hubble Space Telescope has been at the forefront of discoveries in the field of astronomy for more than 20 years. It was the first telescope designed to be serviced in space and the last such servicing mission occurred in May 2009. The question of how much longer this valuable resource can continue to return science data remains. In this paper a detailed analysis of the total dose exposure of electronic parts at the box level is performed using solid angle sectoring/3-dimensional ray trace and Monte Carlo radiation transport simulations. Results are related to parts that have been proposed as possible total dose concerns. The spacecraft subsystem that appears to be at the greatest risk for total dose failure is identified. This is discussed with perspective on the overall lifetime of the spacecraft.

  12. Transient internally driven aurora at Jupiter discovered by Hisaki and the Hubble Space Telescope

    Science.gov (United States)

    Kimura, T.; Badman, S. V.; Tao, C.; Yoshioka, K.; Murakami, G.; Yamazaki, A.; Tsuchiya, F.; Bonfond, B.; Steffl, A. J.; Masters, A.; Kasahara, S.; Hasegawa, H.; Yoshikawa, I.; Fujimoto, M.; Clarke, J. T.

    2015-03-01

    Jupiter's auroral emissions reveal energy transport and dissipation through the planet's giant magnetosphere. While the main auroral emission is internally driven by planetary rotation in the steady state, transient brightenings are generally thought to be triggered by compression by the external solar wind. Here we present evidence provided by the new Hisaki spacecraft and the Hubble Space Telescope that shows that such brightening of Jupiter's aurora can in fact be internally driven. The brightening has an excess power up to ~550 GW. Intense emission appears from the polar cap region down to latitudes around Io's footprint aurora, suggesting a rapid energy input into the polar region by the internal plasma circulation process.

  13. Unveiling the nature of bright z ~ 7 galaxies with the Hubble Space Telescope

    CERN Document Server

    Bowler, R A A; McLure, R J; McLeod, D J

    2016-01-01

    We present new Hubble Space Telescope/Wide Field Camera 3 imaging of 25 extremely luminous (-23.2 600A). We find that irregular, multiple-component morphologies suggestive of clumpy or merging systems are common (f_multi > 0.4) in bright z ~ 7 galaxies, and ubiquitous at the very bright end (M_UV 1000 similarly bright galaxies at z ~ 7. Our new HST imaging suggests that the vast majority of these galaxies will be spatially resolved by Euclid, mitigating concerns over dwarf star contamination.

  14. The shape and surface variation of 2 Pallas from the Hubble Space Telescope.

    Science.gov (United States)

    Schmidt, B E; Thomas, P C; Bauer, J M; Li, J-Y; McFadden, L A; Mutchler, M J; Radcliffe, S C; Rivkin, A S; Russell, C T; Parker, J Wm; Stern, S A

    2009-10-09

    We obtained Hubble Space Telescope images of 2 Pallas in September 2007 that reveal distinct color and albedo variations across the surface of this large asteroid. Pallas's shape is an ellipsoid with radii of 291 (+/-9), 278 (+/-9), and 250 (+/-9) kilometers, implying a density of 2400 (+/-250) kilograms per cubic meter-a value consistent with a body that formed from water-rich material. Our observations are consistent with the presence of an impact feature, 240 (+/-25) kilometers in diameter, within Pallas's ultraviolet-dark terrain. Our observations imply that Pallas is an intact protoplanet that has undergone impact excavation and probable internal alteration.

  15. Wide Field Camera 3: A Powerful New Imager for the Hubble Space Telescope

    Science.gov (United States)

    Kimble, Randy

    2008-01-01

    Wide Field Camera 3 (WFC3) is a powerful UV/visible/near-infrared camera in development for installation into the Hubble Space Telescope during upcoming Servicing Mission 4. WFC3 provides two imaging channels. The UVIS channel incorporates a 4096 x 4096 pixel CCD focal plane with sensitivity from 200 to 1000 nm. The IR channel features a 1024 x 1024 pixel HgCdTe focal plane covering 850 to 1700 nm. We report here on the design of the instrument, the performance of its flight detectors, results of the ground test and calibration program, and the plans for the Servicing Mission installation and checkout.

  16. Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

    Science.gov (United States)

    2012-04-20

    reserved. Printed in the U.S.A. EVIDENCE FOR TYPE Ia SUPERNOVA DIVERSITY FROM ULTRAVIOLET OBSERVATIONS WITH THE HUBBLE SPACE TELESCOPE Xiaofeng Wang1,2,3...DATES COVERED 00-00-2012 to 00-00-2012 4. TITLE AND SUBTITLE Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the...spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on

  17. Proper Motions of Dwarf Spheroidal Galaxies from Hubble Space Telescope Imaging: III. Measurement for URSA Minor

    Science.gov (United States)

    2005-07-01

    The orbit is retrograde and inclined by 124 (94 , 136 ) to the Galactic plane . Ursa Minor is not a likely member of a proposed stream of galaxies...on similar orbits around the Milky Way, nor is the plane of its orbit coincident with a recently proposed planar alignment of galaxies around the...Hubble Space Telescope (HST ). However, Carrera et al. (2002) determine (mM )0 ¼ 19:4 0:1, which gives a distance of 76 4 kpc (note an erroneous

  18. Hubble Space Telescope Studies of Exposed White Dwarfs in Dwarf Novae

    Science.gov (United States)

    Sion, Edward M.

    Coordinated AAVSO optical observations and Hubble Space Telescope (HST) far ultraviolet (UV) spectroscopic observations of cataclysmic variables, during dwarf nova quiescence when the underlying white dwarf is exposed in the far UV, have yielded a number of new insights into accretional heating, photospheric abundances of the accreted atmosphere, and rotational velocities of the underlying degenerates. Recent results of synthetic spectral analyses of HST spectra are highlighted. Their impact on our understanding of accretion physics and the effect of accretion on the white dwarf are discussed.

  19. Artificial neural network for the determination of Hubble Space Telescope aberration from stellar images

    Science.gov (United States)

    Barrett, Todd K.; Sandler, David G.

    1993-01-01

    An artificial-neural-network method, first developed for the measurement and control of atmospheric phase distortion, using stellar images, was used to estimate the optical aberration of the Hubble Space Telescope. A total of 26 estimates of distortion was obtained from 23 stellar images acquired at several secondary-mirror axial positions. The results were expressed as coefficients of eight orthogonal Zernike polynomials: focus through third-order spherical. For all modes other than spherical the measured aberration was small. The average spherical aberration of the estimates was -0.299 micron rms, which is in good agreement with predictions obtained when iterative phase-retrieval algorithms were used.

  20. Updated Status and Performance of the Cosmic Origins Spectrograph on the Hubble Space Telescope

    Science.gov (United States)

    Fix, Mees Bernard; De Rosa, Gisella; Fox, Andrew; Indriolo, Nick; James, Bethan; Jedrzejewski, Robert I.; Oliveira, Cristina M.; Penton, Steven V.; Plesha, Rachel; Rafelski, Marc; Roman-Duval, Julia; Sahnow, David J.; Sonnentrucker, Paule; Snyder, Elaine M.; Taylor, Joanna M.; White, James

    2017-01-01

    The Cosmic Origins Spectrograph (COS) was installed on the Hubble Space Telescope (HST) in May 2009. COS was designed to perform high-sensitivity medium and low-resolution spectroscopy of astronomical objects in the far-ultraviolet (FUV) and near-ultraviolet (NUV) wavelength regimes. Here, we present updates on the time-dependent sensitivities (TDS) for the NUV and FUV detectors, NUV wavelength calibration, and the FUV and NUV dark rates. Additionally, we discuss the move to lifetime position four (LP4) planned for July 2017, including the detector location and impact on resolution.

  1. STS 31 PAYLOAD HUBBLE SPACE TELESCOPE ENCLOSED IN AN AIR-TIGHT PLASTIC BAG FOR PROTECTION IN VERTICA

    Science.gov (United States)

    1989-01-01

    Preparations are made to enclose the Hubble Space Telescope [HST] inside an air-tight plastic bag in the VPF. Processing of the 94- inch primary mirror telescope for launch on the Discovery in March 1990, involves working within strict controls to prevent contamination.

  2. Hubble Space Telescope Constraints on the Winds and Astrospheres of Red Giant Stars

    Science.gov (United States)

    Wood, Brian E.; Müller, Hans-Reinhard; Harper, Graham M.

    2016-10-01

    We report on an ultraviolet spectroscopic survey of red giants observed by the Hubble Space Telescope, focusing on spectra of the Mg ii h and k lines near 2800 Å in order to study stellar chromospheric emission, winds, and astrospheric absorption. We focus on spectral types between K2 III and M5 III, a spectral type range with stars that are noncoronal, but possessing strong, chromospheric winds. We find a very tight relation between Mg ii surface flux and photospheric temperature, supporting the notion that all K2-M5 III stars are emitting at a basal flux level. Wind velocities (V w ) are generally found to decrease with spectral type, with V w decreasing from ˜40 km s-1 at K2 III to ˜20 km s-1 at M5 III. We find two new detections of astrospheric absorption, for σ Pup (K5 III) and γ Eri (M1 III). This absorption signature had previously only been detected for α Tau (K5 III). For the three astrospheric detections, the temperature of the wind after the termination shock (TS) correlates with V w , but is lower than predicted by the Rankine-Hugoniot shock jump conditions, consistent with the idea that red giant TSs are radiative shocks rather than simple hydrodynamic shocks. A full hydrodynamic simulation of the γ Eri astrosphere is provided to explore this further. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program GO-13462. This paper also presents observations obtained with the Harlan J. Smith Telescope at McDonald Observatory of the University of Texas at Austin.

  3. Space Telescope and Optical Reverberation Mapping Project.I. Ultraviolet Observations of the Seyfert 1 Galaxy NGC 5548 with the Cosmic Origins Spectrograph on Hubble Space Telescope

    NARCIS (Netherlands)

    De Rosa, G.; Peterson, B.M.; Ely, J.; Kriss, G.A.; Crenshaw, D.M.; Horne, K.; Korista, K.T.; Netzer, H.; Pogge, R.W.; Arévalo, P.; Barth, A.J.; Bentz, M.C.; Brandt, W.N.; Breeveld, A.A.; Brewer, B.J.; Dalla Bontà, E.; De Lorenzo-Cáceres, A.; Denney, K.D.; Dietrich, M.; Edelson, R.; Evans, P.A.; Fausnaugh, M.M.; Gehrels, N.; Gelbord, J.M.; Goad, M.R.; Grier, C.J.; Grupe, D.; Hall, P.B.; Kaastra, J.; Kelly, B.C.; Kennea, J.A.; Kochanek, C.S.; Lira, P.; Mathur, S.; McHardy, I.M.; Nousek, J.A.; Pancoast, A.; Papadakis, I.; Pei, L.; Schimoia, J.S.; Siegel, M.; Starkey, D.; Treu, T.; Uttley, P.; Vaughan, S.; Vestergaard, M.; Villforth, C.; Yan, H.; Young, S.; Zu, Y.

    2015-01-01

    We describe the first results from a six-month long reverberation-mapping experiment in the ultraviolet based on 171 observations of the Seyfert 1 galaxy NGC 5548 with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Significant correlated variability is found in the continuum and

  4. Transit infrared spectroscopy of the hot neptune around GJ 436 with the Hubble Space Telescope

    CERN Document Server

    Pont, F; Knutson, H; Holman, M; Charbonneau, D

    2008-01-01

    The nearby transiting system GJ 436b offers a unique opportunity to probe the structure and atmosphere of an extra-solar "hot Neptune". In this Letter, we present the main results of observations covering two transit events with the NICMOS camera on the Hubble Space Telescope. The data consist in high-cadence time series of grism spectra covering the 1.1-1.9 micron spectral range. We find Rpl=4.04 +- 0.10 R_earth and R_*= 0.446 +- 0.011 R_sun for the planet and star radius, confirming and improving earlier measurements with ground-based photometry and a Spitzer lightcurve at 8 microns, as opposed to a much higher value obtained with the Fine Guidance Sensor on the Hubble Space Telescope. We measure no departure from strict periodicity in the transits to the level of ~7 seconds. This strongly disfavours the proposed explanation of the orbital eccentricity of GJ 436b in terms of the perturbation by another close-by planet. We measure a flat transmission spectrum at the level of a few parts per 10'000 in flux, w...

  5. New Hubble Space Telescope Observations of Heavy Elements in Four Metal-Poor Stars

    CERN Document Server

    Roederer, Ian U; Sobeck, Jennifer S; Beers, Timothy C; Cowan, John J; Frebel, Anna; Ivans, Inese I; Schatz, Hendrik; Sneden, Christopher; Thompson, Ian B

    2012-01-01

    Elements heavier than the iron group are found in nearly all halo stars. A substantial number of these elements, key to understanding neutron-capture nucleosynthesis mechanisms, can only be detected in the near-ultraviolet. We report the results of an observing campaign using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope to study the detailed heavy element abundance patterns in four metal-poor stars. We derive abundances or upper limits from 27 absorption lines of 15 elements produced by neutron-capture reactions, including seven elements (germanium, cadmium, tellurium, lutetium, osmium, platinum, and gold) that can only be detected in the near-ultraviolet. We also examine 202 heavy element absorption lines in ground-based optical spectra obtained with the Magellan Inamori Kyocera Echelle Spectrograph on the Magellan-Clay Telescope at Las Campanas Observatory and the High Resolution Echelle Spectrometer on the Keck I Telescope on Mauna Kea. We have detected up to 34 elements hea...

  6. Constraining dust and color variations of high-z SNe using NICMOS on Hubble Space Telescope

    CERN Document Server

    Nobili, S; Aldering, G; Amanullah, R; Barbary, K; Burns, M S; Dawson, K S; Deustua, S E; Faccioli, L; Fruchter, A S; Goldhaber, G; Goobar, A; Hook, I; Howell, D A; Kim, A G; Knop, R A; Lidman, C; Meyers, J; Nugent, P E; Pain, R; Panagia, N; Perlmutter, S; Rubin, D; Spadafora, A L; Strovink, M; Suzuki, N; Swift, H

    2009-01-01

    We present data from the Supernova Cosmology Project for five high redshift Type Ia supernovae (SNe Ia) that were obtained using the NICMOS infrared camera on the Hubble Space Telescope. We add two SNe from this sample to a rest-frame I-band Hubble diagram, doubling the number of high redshift supernovae on this diagram. This I-band Hubble diagram is consistent with a flat universe (Omega_Matter, Omega_Lambda= 0.29, 0.71). A homogeneous distribution of large grain dust in the intergalactic medium (replenishing dust) is incompatible with the data and is excluded at the 5 sigma confidence level, if the SN host galaxy reddening is corrected assuming R_V=1.75. We use both optical and infrared observations to compare photometric properties of distant SNe Ia with those of nearby objects. We find generally good agreement with the expected color evolution for all SNe except the highest redshift SN in our sample (SN 1997ek at z=0.863) which shows a peculiar color behavior. We also present spectra obtained from ground ...

  7. Hubble Space Telescope ACS mosaic of the prototypical starburst galaxy M82

    CERN Document Server

    Mutchler, M; Christian, C A; Frattare, L M; Hamilton, F; Januszewski, W; Levay, Z G; Mountain, M; Noll, K S; Royle, P; Gallagher, J S; Puxley, P

    2006-01-01

    In March 2006, the Hubble Heritage Team obtained a large four-filter (B, V, I, and H-alpha) six-point mosaic dataset of the prototypical starburst galaxy NGC 3034 (M82), with the Advanced Camera for Surveys (ACS) onboard the Hubble Space Telescope (HST). The resulting color composite Heritage image was released in April 2006, to celebrate Hubble's 16th anniversary. Cycle 15 HST proposers were encouraged to submit General Observer and Archival Research proposals to complement or analyze this unique dataset. Since our M82 mosaics represent a significant investment of expert processing beyond the standard archival products, we will also release our drizzle combined FITS data as a High Level Science Product via the Multimission Archive at STScI (MAST) on December 31, 2006. This paper documents the key aspects of the observing program and image processing: calibration, image registration and combination (drizzling), and the rejection of cosmic rays and detector artifacts. Our processed FITS mosaics and related inf...

  8. Micrometeoroid Impacts on the Hubble Space Telescope Wide Field and Planetary Camera 2: Smaller Particle Impacts

    Science.gov (United States)

    Ross, D. K.; Anz-Meador, P.; Liou, J.C.; Opiela, J.; Kearsley, A. T.; Grime, G.; Webb, R.; Jeynes, C.; Palitsin, V.; Colaux, J.; hide

    2014-01-01

    The radiator shield on the Wide Field and Planetary Camera 2 (WFPC2) was subject to optical inspection following return from the Hubble Space Telescope (HST) in 2009. The survey revealed over 600 impact features of > 300 micrometers diameter, from exposure in space for 16 years. Subsequently, an international collaborative programme of analysis was organized to determine the origin of hypervelocity particles responsible for the damage. Here we describe examples of the numerous smaller micrometeoroid (MM) impact features (< 700 micrometers diameter) which excavated zinc orthotitanate (ZOT) paint from the radiator surface, but did not incorporate material from underlying Al alloy; larger impacts are described by [3]. We discuss recognition and interpretation of impactor remains, and MM compositions found on WFPC2.

  9. Hubble Space Telescope Near-Ultraviolet Spectroscopy of Bright CEMP-s Stars

    Science.gov (United States)

    Placco, Vinicius M.; Beers, Timothy C.; Ivans, Inese I.; Filler, Dan; Imig, Julie A.; Roederer, Ian U.; Abate, Carlo; Hansen, Terese; Cowan, John J.; Frebel, Anna; Lawler, James E.; Schatz, Hendrik; Sneden, Christopher; Sobeck, Jennifer S.; Aoki, Wako; Smith, Verne V.; Bolte, Michael

    2015-10-01

    We present an elemental-abundance analysis, in the near-ultraviolet (NUV) spectral range, for the bright carbon-enhanced metal-poor (CEMP) stars HD 196944 (V=8.40, [Fe/H] = -2.41) and HD 201626 (V=8.16, [Fe/H] = -1.51), based on data acquired with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope. Both of these stars belong to the sub-class CEMP-s, and exhibit clear over-abundances of heavy elements associated with production by the slow neutron-capture process. HD 196944 has been well-studied in the optical region, but we add abundance results for six species (Ge, Nb, Mo, Lu, Pt, and Au) that are only accessible in the NUV. In addition, we provide the first determination of its orbital period, P = 1325 days. HD 201626 has only a limited number of abundance results based on previous optical work—here we add five new species from the NUV, including Pb. We compare these results with models of binary-system evolution and s-process element production in stars on the asymptotic giant branch, with the goal of explaining their origin and evolution. Our best-fitting models for HD 196944 ({M}1,i=0.9{M}⊙ , {M}2,i=0.86{M}⊙ , for [Fe/H] = -2.2), and HD 201626 ({M}1,i=0.9{M}⊙ , {M}2,i=0.76{M}⊙ , for [Fe/H] = -2.2; {M}1,i=1.6{M}⊙ , {M}2,i=0.59{M}⊙ , for [Fe/H] = -1.5) are consistent with the current accepted scenario for the formation of CEMP-s stars. The data presented herein were obtained with the (i) NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. (These observations are associated with program GO-12554, data sets OBQ601010-30 and OBQ602010-30.); and (ii) W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. (The Observatory was made

  10. Small-Scale Mechanical Characterization of Space-Exposed Fluorinated Ethylene Propylene Recovered from the Hubble Space Telescope

    Science.gov (United States)

    Jones, J. S.; Sharon, J. A.; Mohammed, J.; Hemker, K. J.

    2012-01-01

    Multi-layer insulation panels from the Hubble Space Telescope have been recovered after 19.1 years of on-orbit service and micro-tensile experiments have been performed to characterize the effect of space exposure on the mechanical response of the outermost layer. This outer layer, 127 m thick fluorinated ethylene propylene with a 100 nm thick vapor deposited aluminum reflective coating, maintained significant tensile ductility but exhibited a degradation of strength that scales with severity of space exposure. This change in properties is attributed to damage from incident solar flux, atomic oxygen damage, and thermal cycling.

  11. The Sirius System and Its Astrophysical Puzzles: Hubble Space Telescope and Ground-based Astrometry

    Science.gov (United States)

    Bond, Howard E.; Schaefer, Gail H.; Gilliland, Ronald L.; Holberg, Jay B.; Mason, Brian D.; Lindenblad, Irving W.; Seitz-McLeese, Miranda; Arnett, W. David; Demarque, Pierre; Spada, Federico; Young, Patrick A.; Barstow, Martin A.; Burleigh, Matthew R.; Gudehus, Donald

    2017-05-01

    Sirius, the seventh-nearest stellar system, is a visual binary containing the metallic-line A1 V star Sirius A, the brightest star in the sky, orbited in a 50.13 year period by Sirius B, the brightest and nearest white dwarf (WD). Using images obtained over nearly two decades with the Hubble Space Telescope (HST), along with photographic observations covering almost 20 years and nearly 2300 historical measurements dating back to the 19th century, we determine precise orbital elements for the visual binary. Combined with the parallax and the motion of the A component, these elements yield dynamical masses of 2.063+/- 0.023 {M}⊙ and 1.018+/- 0.011 {M}⊙ for Sirius A and B, respectively. Our precise HST astrometry rules out third bodies orbiting either star in the system, down to masses of ˜15-25 {M}{Jup}. The location of Sirius B in the Hertzsprung-Russell diagram is in excellent agreement with theoretical cooling tracks for WDs of its dynamical mass, and implies a cooling age of ˜126 Myr. The position of Sirius B on the mass-radius plane is also consistent with WD theory, assuming a carbon-oxygen core. Including the pre-WD evolutionary timescale of the assumed progenitor, the total age of Sirius B is about 228 ± 10 Myr. We calculated evolutionary tracks for stars with the dynamical mass of Sirius A, using two independent codes. We find it necessary to assume a slightly subsolar metallicity, of about 0.85 {Z}⊙ , to fit its location on the luminosity-radius plane. The age of Sirius A based on these models is about 237-247 Myr, with uncertainties of ±15 Myr, consistent with that of the WD companion. We discuss astrophysical puzzles presented by the Sirius system, including the probability that the two stars must have interacted in the past, even though there is no direct evidence for this and the orbital eccentricity remains high. Based in part on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, and from

  12. THE SPACE MOTION OF LEO I: HUBBLE SPACE TELESCOPE PROPER MOTION AND IMPLIED ORBIT

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Sangmo Tony; Van der Marel, Roeland P. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Besla, Gurtina [Department of Astronomy, Columbia University, New York, NY 10027 (United States); Boylan-Kolchin, Michael; Bullock, James S. [Department of Physics and Astronomy, Center for Cosmology, University of California, 4129 Reines Hall, Irvine, CA 92697 (United States); Majewski, Steven R., E-mail: tsohn@stsci.edu [Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325 (United States)

    2013-05-10

    We present the first absolute proper motion measurement of Leo I, based on two epochs of Hubble Space Telescope ACS/WFC images separated by {approx}5 years in time. The average shift of Leo I stars with respect to {approx}100 background galaxies implies a proper motion of ({mu}{sub W}, {mu}{sub N}) = (0.1140 {+-} 0.0295, -0.1256 {+-} 0.0293) mas yr{sup -1}. The implied Galactocentric velocity vector, corrected for the reflex motion of the Sun, has radial and tangential components V{sub rad} = 167.9 {+-} 2.8 km s{sup -1} and V{sub tan} = 101.0 {+-} 34.4 km s{sup -1}, respectively. We study the detailed orbital history of Leo I by solving its equations of motion backward in time for a range of plausible mass models for the Milky Way (MW) and its surrounding galaxies. Leo I entered the MW virial radius 2.33 {+-} 0.21 Gyr ago, most likely on its first infall. It had a pericentric approach 1.05 {+-} 0.09 Gyr ago at a Galactocentric distance of 91 {+-} 36 kpc. We associate these timescales with characteristic timescales in Leo I's star formation history, which shows an enhanced star formation activity {approx}2 Gyr ago and quenching {approx}1 Gyr ago. There is no indication from our calculations that other galaxies have significantly influenced Leo I's orbit, although there is a small probability that it may have interacted with either Ursa Minor or Leo II within the last {approx}1 Gyr. For most plausible MW masses, the observed velocity implies that Leo I is bound to the MW. However, it may not be appropriate to include it in models of the MW satellite population that assume dynamical equilibrium, given its recent infall. Solution of the complete (non-radial) timing equations for the Leo I orbit implies an MW mass M{sub MW,vir} = 3.15{sub -1.36}{sup +1.58} x 10{sup 12} M{sub Sun }, with the large uncertainty dominated by cosmic scatter. In a companion paper, we compare the new observations to the properties of Leo I subhalo analogs extracted from cosmological

  13. Precision Measurement of The Most Distant Spectroscopically-Confirmed Supernova Ia with the Hubble Space Telescope

    CERN Document Server

    Rubin, D; Rykoff, E; Aldering, G; Amanullah, R; Barbary, K; Burns, M S; Conley, A; Connolly, N; Deustua, S; Fadeyev, V; Fakhouri, H K; Fruchter, A S; Gibbons, R A; Goldhaber, G; Goobar, A; Hsiao, E Y; Huang, X; Kowalski, M; Lidman, C; Meyers, J; Nordin, J; Perlmutter, S; Saunders, C; Spadafora, A L; Stanishev, V; Suzuki, N; Wang, L

    2012-01-01

    We report the discovery of a redshift 1.71 supernova in the GOODS North field. The Hubble Space Telescope (HST) ACS spectrum has almost negligible contamination from the host or neighboring galaxies, allowing us to confirm it as a Type Ia. A serendipitous HST WFC3 IR spectrum, taken after the supernova had faded, gives a host-galaxy redshift of 1.713 +/- 0.007 which matches the SN redshift. In addition to being the most distant SN Ia with spectroscopic confirmation, this is the most distant Ia with a precision color measurement. We present the ACS WFC and NICMOS 2 photometry and ACS and WFC3 spectroscopy. Our derived supernova distance is in agreement with the prediction of LambdaCDM.

  14. Hubble Space Telescope astrometry of the closest brown dwarf binary system - I. Overview and improved orbit★

    Science.gov (United States)

    Bedin, L. R.; Pourbaix, D.; Apai, D.; Burgasser, A. J.; Buenzli, E.; Boffin, H. M. J.; Libralato, M.

    2017-09-01

    Located at 2 pc, the L7.5+T0.5 dwarfs system WISE J104915.57-531906.1 (Luhman 16 AB) is the third closest system known to Earth, making it a key benchmark for detailed investigation of brown dwarf atmospheric properties, thermal evolution, multiplicity, and planet-hosting frequency. In the first study of this series - based on a multicycle Hubble Space Telescope (HST) program - we provide an overview of the project and present improved estimates of positions, proper motions, annual parallax, mass ratio, and the current best assessment of the orbital parameters of the A-B pair. Our HST observations encompass the apparent periastron of the binary at 220.5 ± 0.2 mas at epoch 2016.402. Although our data seem to be inconsistent with recent ground-based astrometric measurements, we also exclude the presence of third bodies down to Neptune masses and periods longer than a year.

  15. Early Scientific Results and Future Prospects for the Rejuvenated Hubble Space Telescope

    Science.gov (United States)

    Niedner, Malcolm B.

    2010-01-01

    Following the extraordinarily successful Servicing Mission 4 (SM4) of Hubble Space Telescope (HST) in May of 2009, the Observatory is now fully equipped with a broad array of powerful science instruments that put it at the pinnacle of its scientific power. Relevant to the subject matter of the Beyond 2010 Conference, HST will be well-placed over the next five-plus years to advance our knowledge of the formation of high-redshift galaxies and their growth with cosmic time; the emergence of structure in the early universe via Dark Matter-driven gravitational instability; and the universe's expansion history and any resulting implications for the temporal character of Dark Energy. These are fitting projects for the iconic facility now celebrating its 20th anniversary in orbit.

  16. Dynamic auroral storms on Saturn as observed by the Hubble Space Telescope.

    Science.gov (United States)

    Nichols, J D; Badman, S V; Baines, K H; Brown, R H; Bunce, E J; Clarke, J T; Cowley, S W H; Crary, F J; Dougherty, M K; Gérard, J-C; Grocott, A; Grodent, D; Kurth, W S; Melin, H; Mitchell, D G; Pryor, W R; Stallard, T S

    2014-05-28

    We present observations of significant dynamics within two UV auroral storms observed on Saturn using the Hubble Space Telescope in April/May 2013. Specifically, we discuss bursts of auroral emission observed at the poleward boundary of a solar wind-induced auroral storm, propagating at ∼330% rigid corotation from near ∼01 h LT toward ∼08 h LT. We suggest that these are indicative of ongoing, bursty reconnection of lobe flux in the magnetotail, providing strong evidence that Saturn's auroral storms are caused by large-scale flux closure. We also discuss the later evolution of a similar storm and show that the emission maps to the trailing region of an energetic neutral atom enhancement. We thus identify the auroral form with the upward field-aligned continuity currents flowing into the associated partial ring current.

  17. New Horizons: Long-Range Kuiper Belt Targets Observed by the Hubble Space Telescope

    Science.gov (United States)

    Benecchi, S. D.; Noll, K. S.; Weaver, H. A.; Spencer, J. R.; Stern, S. A.; Buie, M. W.; Parker, A. H.

    2014-01-01

    We report on Hubble Space Telescope (HST) observations of three Kuiper Belt Objects (KBOs), discovered in our dedicated ground-based search campaign, that are candidates for long-range observations from the New Horizons spacecraft: 2011 epochY31, 2011 HZ102, and 2013 LU35. Astrometry with HST enables both current and future critical accuracy improvements for orbit precision, required for possible New Horizons observations, beyond what can be obtained from the ground. Photometric colors of all three objects are red, typical of the Cold Classical dynamical population within which they reside; they are also the faintest KBOs to have had their colors measured. None are observed to be binary with HST above separations of approx. 0.02 arcsec (approx. 700 km at 44 AU) and delta m less than or equal to 0.5.

  18. Low Frequency Flats for Imaging Cameras on the Hubble Space Telescope

    Science.gov (United States)

    Kossakowski, Diana; Avila, Roberto J.; Borncamp, David; Grogin, Norman A.

    2017-01-01

    We created a revamped Low Frequency Flat (L-Flat) algorithm for the Hubble Space Telescope (HST) and all of its imaging cameras. The current program that makes these calibration files does not compile on modern computer systems and it requires translation to Python. We took the opportunity to explore various methods that reduce the scatter of photometric observations using chi-squared optimizers along with Markov Chain Monte Carlo (MCMC). We created simulations to validate the algorithms and then worked with the UV photometry of the globular cluster NGC6681 to update the calibration files for the Advanced Camera for Surveys (ACS) and Solar Blind Channel (SBC). The new software was made for general usage and therefore can be applied to any of the current imaging cameras on HST.

  19. Maintaining an expert system for the Hubble Space Telescope ground support

    Science.gov (United States)

    Lindenmayer, Kelly; Vick, Shon; Rosenthal, Don

    1987-01-01

    The transformation portion of the Hubble Space Telescope (HST) Proposal Entry Processor System converts astronomer-oriented description of a scientific observing program into a detailed description of the parameters needed for planning and scheduling. The transformation system is one of a very few rulebased expert systems that has ever entered an operational phase. The day to day operations of the system and its rulebase are no longer the responsibility of the original developer. As a result, software engineering properties of the rulebased approach become more important. Maintenance issues associated with the coupling of rules within a rulebased system are discussed and a method is offered for partitioning a rulebase so that the amount of knowledge needed to modify the rulebase is minimized. This method is also used to develop a measure of the coupling strength of the rulebase.

  20. A natural language query system for Hubble Space Telescope proposal selection

    Science.gov (United States)

    Hornick, Thomas; Cohen, William; Miller, Glenn

    1987-01-01

    The proposal selection process for the Hubble Space Telescope is assisted by a robust and easy to use query program (TACOS). The system parses an English subset language sentence regardless of the order of the keyword phases, allowing the user a greater flexibility than a standard command query language. Capabilities for macro and procedure definition are also integrated. The system was designed for flexibility in both use and maintenance. In addition, TACOS can be applied to any knowledge domain that can be expressed in terms of a single reaction. The system was implemented mostly in Common LISP. The TACOS design is described in detail, with particular attention given to the implementation methods of sentence processing.

  1. Young Planetary Nebulae: Hubble Space Telescope Imaging and a New Morphological Classification System

    CERN Document Server

    Sahai, Raghvendra; Villar, Gregory G

    2011-01-01

    Using Hubble Space Telescope images of 119 young planetary nebulae, most of which have not previously been published, we have devised a comprehensive morphological classification system for these objects. This system generalizes a recently devised system for pre-planetary nebulae, which are the immediate progenitors of planetary nebulae (PNs). Unlike previous classification studies, we have focussed primarily on young PNs rather than all PNs, because the former best show the influences or symmetries imposed on them by the dominant physical processes operating at the first and primary stage of the shaping process. Older PNs develop instabilities, interact with the ambient interstellar medium, and are subject to the passage of photoionization fronts, all of which obscure the underlying symmetries and geometries imposed early on. Our classification system is designed to suffer minimal prejudice regarding the underlying physical causes of the different shapes and structures seen in our PN sample, however, in many...

  2. MULTI-WAVELENGTH HUBBLE SPACE TELESCOPE PHOTOMETRY OF STELLAR POPULATIONS IN NGC 288

    Energy Technology Data Exchange (ETDEWEB)

    Piotto, G. [Dipartimento di Fisica e Astronomia, ' ' Galileo Galilei' ' Universita di Padova, Vicolo dell' Osservatorio 3, Padova I-35122 (Italy); Milone, A. P.; Marino, A. F.; Jerjen, H. [Research School of Astronomy and Astrophysics, Australian National University, Cotter Road, Weston, ACT 2611 (Australia); Bedin, L. R. [INAF-Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padua (Italy); Anderson, J.; Bellini, A. [Space Telescope Science Institute, 3800 San Martin Drive, Baltimore, MD 21218 (United States); Cassisi, S., E-mail: giampaolo.piotto@unipd.it, E-mail: luigi.bedin@oapd.inaf.it, E-mail: milone@mso.anu.edu.au, E-mail: amarino@mso.anu.edu.au, E-mail: jerjen@mso.anu.edu.au, E-mail: jayander@stsci.edu, E-mail: bellini@stsci.edu, E-mail: cassisi@oa-teramo.inaf.it [INAF-Osservatorio Astronomico di Collurania, via Mentore Maggini, I-64100 Teramo (Italy)

    2013-09-20

    We present new UV observations for NGC 288, taken with the WFC3 detector on board the Hubble Space Telescope, and combine them with existing optical data from the archive to explore the multiple-population phenomenon in this globular cluster (GC). The WFC3's UV filters have demonstrated an uncanny ability to distinguish multiple populations along all photometric sequences in GCs thanks to their exquisite sensitivity to the atmospheric changes that are telltale signs of second-generation enrichment. Optical filters, on the other hand, are more sensitive to stellar-structure changes related to helium enhancement. By combining both UV and optical data, we can measure the helium variation. We quantify this enhancement for NGC 288 and find that the variation is typical of what we have come to expect in other clusters.

  3. Hubble Space Telescope Ultraviolet Light Curves Reveal Interesting Properties of CC Sculptoris and RZ Leonis

    Science.gov (United States)

    Szkody, Paula; Mukadam, Anjum S.; Toloza, Odette; Gänsicke, Boris T.; Dai, Zhibin; Pala, Anna F.; Waagen, Elizabeth O.; Godon, Patrick; Sion, Edward M.

    2017-03-01

    Time-tag ultraviolet data obtained on the Hubble Space Telescope in 2013 reveal interesting variability related to the white dwarf spin in the two cataclysmic variables RZ Leo and CC Scl. RZ Leo shows a period at 220 s and its harmonic at 110 s, thus identifying it as a likely Intermediate Polar (IP). The spin signal is not visible in a short single night of ground-based data in 2016, but the shorter exposures in that data set indicate a possible partial eclipse. The much larger UV amplitude of the spin signal in the known IP CC Scl allows the spin of 389 s, previously only seen at outburst, to be visible at quiescence. Spectra created from the peaks and troughs of the spin times indicate a hotter temperature of several thousand degrees during the peak phases, with multiple components contributing to the UV light.

  4. Astrometry with the Hubble Space Telescope: Trigonometric Parallaxes of Selected Hyads

    CERN Document Server

    McArthur, Barbara E; Harrison, Thomas E; van Altena, William

    2011-01-01

    We present absolute parallaxes and proper motions for seven members of the Hyades open cluster, pre-selected to lie in the core of the cluster. Our data come from archival astrometric data from FGS 3, and newer data for 3 Hyads from FGS 1R, both white-light interferometers on the Hubble Space Telescope (HST). We obtain member parallaxes from six individual Fine Guidance Sensor (FGS) fields and use the field containing van Altena 622 and van Altena 627 (= HIP 21138) as an example. Proper motions, spectral classifications and VJHK photometry of the stars comprising the astrometric refer- ence frames provide spectrophotometric estimates of reference star absolute parallaxes. Introducing these into our model as observations with error, we determine absolute parallaxes for each Hyad. The parallax of vA 627 is significantly improved by including a perturbation orbit for this previously known spectroscopic binary, now an astrometric binary. Compared to our original (1997) determina- tions, a combination of new data,...

  5. Hubble Space Telescope Optical Imaging of the Eroding Debris Disk HD 61005

    CERN Document Server

    Maness, H L; Peek, K M G; Chiang, E I; Scherer, K; Fitzgerald, M P; Graham, James R; Hines, D C; Schneider, G; Metchev, S A

    2009-01-01

    We present Hubble Space Telescope optical coronagraphic polarization imaging observations of the dusty debris disk HD 61005. The scattered light intensity image and polarization structure reveal a highly inclined disk with a clear asymmetric, swept back component, suggestive of significant interaction with the ambient interstellar medium. The combination of our new data with the published 1.1 micron discovery image shows that the grains are blue scattering with no strong color gradient as a function of radius, implying predominantly sub-micron sized grains. We investigate possible explanations that could account for the observed swept back, asymmetric morphology. Previous work has suggested that HD 61005 may be interacting with a cold, unusually dense interstellar cloud. However, limits on the intervening interstellar gas column density from an optical spectrum of HD 61005 in the Na I D lines render this possibility unlikely. Instead, HD 61005 may be embedded in a more typical warm, low-density cloud that int...

  6. Hubble Space Telescope: Snapshot Survey for Resolved Companions of Galactic Cepheids

    CERN Document Server

    Evans, Nancy Remage; Schaefer, Gail H; Mason, Brian D; Tingle, Evan; Karovska, Margarita; Pillitteri, Ignazio

    2016-01-01

    We have conducted an imaging survey with the Hubble Space Telescope Wide Field Camera~3 (WFC3) of 70 Galactic Cepheids, typically within 1~kpc, with the aim of finding resolved physical companions. The WFC3 field typically covers the 0.1 pc area where companions are expected. In this paper, we identify 39 Cepheids having candidate companions, based on their positions in color--magnitude diagrams, and having separations $\\geq$5$"$ from the Cepheids. We use follow-up observations of 14 of these candidates with XMM-Newton, and of one of them with ROSAT, to separate X-ray-active young stars (probable physical companions) from field stars (chance alignments). Our preliminary estimate, based on the optical and X-ray observations, is that only 3\\% of the Cepheids in the sample have wide companions. Our survey easily detects resolved main-sequence companions as faint as spectral type K\

  7. White Dwarf - Red Dwarf Systems Resolved with the Hubble Space Telescope. II. Full Snapshot Survey Results

    CERN Document Server

    Farihi, J; Wachter, S

    2010-01-01

    {Abrigded} Results are presented for a Hubble Space Telescope Advanced Camera for Surveys high-resolution imaging campaign of 90 white dwarfs with known or suspected low mass stellar and substellar companions. Of the 72 targets which remain candidate and confirmed white dwarfs with near-infrared excess, 43 are spatially resolved into two or more components, and a total of 12 systems are potentially triples. There is a possible, slight deficit of earlier spectral types (bluer colors) among the spatially unresolved companions, exactly the opposite of expectations if significant mass is transferred to the companion during the common envelope phase. Using the best available distance estimates, the low mass companions to white dwarfs exhibit a bimodal distribution in projected separation. This result supports the hypothesis that during the giant phases of the white dwarf progenitor, any unevolved companions either migrate inward to short periods of hours to days, or outward to periods of hundreds to thousands of y...

  8. Hubble space telescope counts of elliptical galaxies constraints on cosmological models?

    CERN Document Server

    Driver, S P; Phillipps, S; Bristow, P D; Driver, Simon P; Windhorst, Rogier A; Phillipps, Steven; Bristow, Paul D

    1995-01-01

    The interpretation of galaxy number counts in terms of cosmological models is fraught with difficulty due to uncertainties in the overall galaxy population (mix of morphological types, luminosity functions etc.) and in the observations (loss of low surface brightness images, image blending etc.). Many of these can be overcome if we use deep high resolution imaging of a single class of high surface brightness galaxies, whose evolution is thought to be fairly well understood. This is now possible by selecting elliptical and S0 galaxies using Hubble Space Telescope images from the Medium Deep Survey and other ultradeep WFPC2 images. In the present paper, we examine whether such data can be used to discriminate between open and closed universes, or between conventional cosmological models and those dominated by a cosmological constant. We find, based on the currently available data, that unless elliptical galaxies undergo very strong merging since z \\sim 1 (and/or very large errors exist in the morphological clas...

  9. New Hubble Space Telescope imaging of the counterparts to six ultraluminous X-ray sources

    CERN Document Server

    Roberts, T P; Goad, M R

    2008-01-01

    We report the results of new Hubble Space Telescope imaging of the positions of six ultraluminous X-ray sources (ULXs). Using images in three ACS filters we detect good candidate counterparts to four out of six ULXs, with one more possible detection, and observed magnitudes in the range m ~ 22 - 26 in the F606W filter. The extinction-corrected colours and absolute magnitudes vary from source to source, even after correcting for additional extinction in the host galaxy, and only one counterpart is readily explained as an OB star. Nevertheless, these counterparts are decent candidates for future follow-up in pursuit of dynamical mass constraints on the likely black holes powering these sources.

  10. Proper Motion of the Leo II Dwarf Galaxy Based On Hubble Space Telescope Imaging

    CERN Document Server

    Piatek, Slawomir; Olszewski, Edward W

    2016-01-01

    This article reports a measurement of the proper motion of Leo II, a dwarf galaxy that is a likely satellite of the Milky Way, based on imaging with the Hubble Space Telescope and Wide Field Camera 3. The measurement uses compact background galaxies as standards of rest in both channels of the camera for two distinct pointings of the telescope and a QSO in one channel for each pointing, resulting in the weighted average of six measurements. The measured proper motion in the the equatorial coordinate system is (mu_alpha, mu_delta) = (-6.9 +- 3.7, -8.7 +- 3.9) mas/century and in the Galactic coordinate system is (mu_l, mu_b) = (6.2 +- 3.9, -9.2 +- 3.7) mas/century. The implied space velocity with respect to the Galactic center is (Pi, Theta, Z) = (-37 +- 38, 117 +- 43, 40 +- 16) km/s or, expressed in Galactocentric radial and tangential components, (V_r, V_tan) = (21.9 +- 1.5, 127 +- 42) km/s. The space velocity implies that the instantaneous orbital inclination is 68 degrees, with a 95% confidence interval of ...

  11. Near-infrared detection of WD 0806-661 B with the Hubble space telescope

    Energy Technology Data Exchange (ETDEWEB)

    Luhman, K. L.; Esplin, T. L. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Morley, C. V. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Burgasser, A. J. [Center for Astrophysics and Space Science, University of California, San Diego, La Jolla, CA 92093 (United States); Bochanski, J. J., E-mail: kluhman@astro.psu.edu [Haverford College, 370 Lancaster Avenue, Haverford, PA 19041 (United States)

    2014-10-10

    WD 0806-661 B is one of the coldest known brown dwarfs (T {sub eff} = 300-345 K) based on previous mid-infrared photometry from the Spitzer Space Telescope. In addition, it is a benchmark for testing theoretical models of brown dwarfs because its age and distance are well constrained via its primary star (2 ± 0.5 Gyr, 19.2 ± 0.6 pc). We present the first near-infrared detection of this object, which has been achieved through F110W imaging (∼Y + J) with the Wide Field Camera 3 on board the Hubble Space Telescope. We measure a Vega magnitude of m {sub 110} = 25.70 ± 0.08, which implies J ∼ 25.0. When combined with the Spitzer photometry, our estimate of J helps to better define the empirical sequence of the coldest brown dwarfs in M {sub 4.5} versus J – [4.5]. The positions of WD 0806-661 B and other Y dwarfs in that diagram are best matched by the cloudy models of Burrows et al. and the cloudless models of Saumon et al., both of which employ chemical equilibrium. The calculations by Morley et al. for 50% cloud coverage differ only modestly from the data. Spectroscopy would enable a more stringent test of the models, but based on our F110W measurement, such observations are currently possible only with Hubble, and would require at least ∼10 orbits to reach a signal-to-noise ratio of ∼5.

  12. The Hubble Space Telescope fine guidance system operating in the coarse track pointing control mode

    Science.gov (United States)

    Whittlesey, Richard

    1993-01-01

    The Hubble Space Telescope (HST) Fine Guidance System has set new standards in pointing control capability for earth orbiting spacecraft. Two precision pointing control modes are implemented in the Fine Guidance System; one being a Coarse Track Mode which employs a pseudo-quadrature detector approach and the second being a Fine Mode which uses a two axis interferometer implementation. The Coarse Track Mode was designed to maintain FGS pointing error to within 20 milli-arc seconds (rms) when guiding on a 14.5 Mv star. The Fine Mode was designed to maintain FGS pointing error to less than 3 milli-arc seconds (rms). This paper addresses the HST FGS operating in the Coarse Track Mode. An overview of the implementation, the operation, and both the predicted and observed on orbit performance is presented. The discussion includes a review of the Fine Guidance System hardware which uses two beam steering Star Selector servos, four photon counting photomultiplier tube detectors, as well as a 24 bit microprocessor, which executes the control system firmware. Unanticipated spacecraft operational characteristics are discussed as they impact pointing performance. These include the influence of spherically aberrated star images as well as the mechanical shocks induced in the spacecraft during and following orbital day/night terminator crossings. Computer modeling of the Coarse Track Mode verifies the observed on orbit performance trends in the presence of these optical and mechanical disturbances. It is concluded that the coarse track pointing control function is performing as designed and is providing a robust pointing control capability for the Hubble Space Telescope.

  13. NEW HUBBLE SPACE TELESCOPE OBSERVATIONS OF HEAVY ELEMENTS IN FOUR METAL-POOR STARS

    Energy Technology Data Exchange (ETDEWEB)

    Roederer, Ian U.; Thompson, Ian B. [Carnegie Observatories, Pasadena, CA 91101 (United States); Lawler, James E. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Sobeck, Jennifer S. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Beers, Timothy C. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Cowan, John J. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States); Frebel, Anna [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Ivans, Inese I. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Schatz, Hendrik [Department of Physics and Astronomy, Michigan State University, E. Lansing, MI 48824 (United States); Sneden, Christopher [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States)

    2012-12-15

    Elements heavier than the iron group are found in nearly all halo stars. A substantial number of these elements, key to understanding neutron-capture nucleosynthesis mechanisms, can only be detected in the near-ultraviolet. We report the results of an observing campaign using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope to study the detailed heavy-element abundance patterns in four metal-poor stars. We derive abundances or upper limits from 27 absorption lines of 15 elements produced by neutron-capture reactions, including seven elements (germanium, cadmium, tellurium, lutetium, osmium, platinum, and gold) that can only be detected in the near-ultraviolet. We also examine 202 heavy-element absorption lines in ground-based optical spectra obtained with the Magellan Inamori Kyocera Echelle Spectrograph on the Magellan-Clay Telescope at Las Campanas Observatory and the High Resolution Echelle Spectrometer on the Keck I Telescope on Mauna Kea. We have detected up to 34 elements heavier than zinc. The bulk of the heavy elements in these four stars are produced by r-process nucleosynthesis. These observations affirm earlier results suggesting that the tellurium found in metal-poor halo stars with moderate amounts of r-process material scales with the rare earth and third r-process peak elements. Cadmium often follows the abundances of the neighboring elements palladium and silver. We identify several sources of systematic uncertainty that must be considered when comparing these abundances with theoretical predictions. We also present new isotope shift and hyperfine structure component patterns for Lu II and Pb I lines of astrophysical interest.

  14. Hubble Space Telescope Near-Ultraviolet Spectroscopy of Bright CEMP-s Stars

    CERN Document Server

    Placco, Vinicius M; Ivans, Inese I; Filler, Dan; Imig, Julie A; Roederer, Ian U; Abate, Carlo; Hansen, Terese; Cowan, John J; Frebel, Anna; Lawler, James E; Schatz, Hendrik; Sneden, Christopher; Sobeck, Jennifer S; Aoki, Wako; Smith, Verne V; Bolte, Michael

    2015-01-01

    We present an elemental-abundance analysis, in the near-ultraviolet (NUV) spectral range, for the bright carbon-enhanced metal-poor (CEMP) stars HD196944 (V = 8.40, [Fe/H] = -2.41) and HD201626 (V = 8.16, [Fe/H] = -1.51), based on data acquired with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope. Both of these stars belong to the sub-class CEMP-s, and exhibit clear over-abundances of heavy elements associated with production by the slow neutron-capture process. HD196944 has been well-studied in the optical region, but we are able to add abundance results for six species (Ge, Nb, Mo, Lu, Pt, and Au) that are only accessible in the NUV. In addition, we provide the first determination of its orbital period, P=1325 days. HD201626 has only a limited number of abundance results based on previous optical work -- here we add five new species from the NUV, including Pb. We compare these results with models of binary-system evolution and s-process element production in stars on the asympt...

  15. Hubble Space Telescope Survey of Interstellar ^12CO/^13CO in the Solar Neighborhood

    CERN Document Server

    Sheffer, Y; Federman, S R; Lambert, D L; Gredel, R

    2007-01-01

    We examine 20 diffuse and translucent Galactic sight lines and extract the column densities of the ^12CO and ^13CO isotopologues from their ultraviolet A--X absorption bands detected in archival Space Telescope Imaging Spectrograph data with lambda/Deltalambda geq 46,000. Five more targets with Goddard High-Resolution Spectrograph data are added to the sample that more than doubles the number of sight lines with published Hubble Space Telescope observations of ^13CO. Most sight lines have 12-to-13 isotopic ratios that are not significantly different from the local value of 70 for ^12C/^13C, which is based on mm-wave observations of rotational lines in emission from CO and H_2CO inside dense molecular clouds, as well as on results from optical measurements of CH^+. Five of the 25 sight lines are found to be fractionated toward lower 12-to-13 values, while three sight lines in the sample are fractionated toward higher ratios, signaling the predominance of either isotopic charge exchange or selective photodissoc...

  16. Deep Hubble Space Telescope WFPC2 Photometry of NGC 288. I. Binary Systems and Blue Stragglers

    Science.gov (United States)

    Bellazzini, Michele; Fusi Pecci, Flavio; Messineo, Maria; Monaco, Lorenzo; Rood, Robert T.

    2002-03-01

    We present the first results of a deep WFPC2 photometric survey of the loose galactic globular cluster NGC 288. The fraction of binary systems is estimated from the color distribution of objects near the main sequence (MS) with a method analogous to that introduced by Rubenstein & Bailyn. We have unequivocally detected a significant population of binary systems with a radial distribution that has been significantly influenced by mass segregation. In the inner region of the cluster (r=1rh), fb must be less than 0.10, and the most likely value is 0.0, independently of the adopted F(q). The detected population of binaries is dominated by primordial systems. The specific frequency of blue stragglers (BSs) is exceptionally high, suggesting that the BS production mechanism via binary evolution can be very efficient. A large population of BSs is possible even in low-density environments if a sufficient reservoir of primordial binaries is available. The observed distribution of BSs in the color-magnitude diagram is not compatible with a rate of BS production that has been constant in time, if it is assumed that all the BSs are formed by the merging of two stars. Based on observations made with the NASA/ESA Hubble Space Telescope at the Space Telescope Science Institute (STScI), which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with proposal GO-6804.

  17. Limits from the Hubble Space Telescope on a Point Source in SN 1987A

    CERN Document Server

    Graves, G J M; Chevalier, R A; Crotts, A; Filippenko, A V; Fransson, C; Garnavich, P M; Kirshner, R P; Li, W; Lundqvist, P; McCray, R; Panagia, N; Phillips, M M; Pun, C J S; Schmidt, B P; Sonneborn, G; Suntzeff, N B; Wang, L; Wheeler, J C; Wheeler, and J. C.

    2005-01-01

    We observed supernova 1987A (SN 1987A) with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) in 1999 September, and again with the Advanced Camera for Surveys (ACS) on the HST in 2003 November. No point source is observed in the remnant. We obtain a limiting flux of F_opt < 1.6 x 10^{-14} ergs/s/cm^2 in the wavelength range 2900-9650 Angstroms for any continuum emitter at the center of the supernova remnant (SNR). It is likely that the SNR contains opaque dust that absorbs UV and optical emission, resulting in an attenuation of ~35% due to dust absorption in the SNR. Taking into account dust absorption in the remnant, we find a limit of L_opt < 8 x 10^{33} ergs/s. We compare this upper bound with empirical evidence from point sources in other supernova remnants, and with theoretical models for possible compact sources. Bright young pulsars such as Kes 75 or the Crab pulsar are excluded by optical and X-ray limits on SN 1987A. Of the young pulsars known to be associated...

  18. Evolution of early-type galaxies in distant clusters : The fundamental plane from Hubble Space Telescope imaging and Keck spectroscopy

    NARCIS (Netherlands)

    Kelson, DD; vanDokkum, PG; Franx, M; Illingworth, GD; Fabricant, D

    1997-01-01

    We present new results on the fundamental plane of galaxies in two rich clusters, Cl 1358+62 at z = 0.33 and MS 2053-04 at z = 0.58, based on Keck and Hubble Space Telescope observations. Our new data triple the sample of galaxies with measured fundamental plane parameters at intermediate redshift.

  19. The Black Hole Mass-Bulge Luminosity Relationship for Active Galactic Nuclei From Reverberation Mapping and Hubble Space Telescope Imaging

    DEFF Research Database (Denmark)

    Bentz, Misty C.; Peterson, Bradley M.; Pogge, Richard W.

    2009-01-01

    We investigate the relationship between black hole mass and bulge luminosity for active galactic nuclei (AGNs) with reverberation-based black hole mass measurements and bulge luminosities from two-dimensional decompositions of Hubble Space Telescope host galaxy images. We find that the slope...

  20. Hubble Space Telescope First Observations of the Brightest Stars in the Virgo Galaxy M100 = NGC 4321

    Science.gov (United States)

    Freedman, W. L.; Madore, B. F.; Stetson, P. B.; Hughes, S. M. G.; Holtzman, J. A.; Mould, J. R.; Trauger, J. T.; Gallagher, J. S., III; Ballester, G. E.; Burrows, C. J.; Casertano, S.; Clarke, J. T; Crisp, D.; Ferrarese, L.; Ford, H.; Graham, J. A.; Griffiths, R. E.; Hester, J. J.; Hill, R.; Hoessel, J. G.; Huchra, J.; Kennicutt, R. C.; Scowen, P. A.; Sparks, B.; Stapelfeldt, K. R.

    1994-01-01

    As part of both the Early Release Observations fromthe Hubble Space Telescope and the Key PRoject on the Extragalctic Distance Scale, we have obtained multi-wavelength BVR WFPC2 images for the face-on Virgo cluster spiral galaxy M11 = NGC 4321.

  1. High-resolution imaging of the Pluto-Charon system with the Faint Object Camera of the Hubble Space Telescope

    Science.gov (United States)

    Albrecht, R.; Barbieri, C.; Adorf, H.-M.; Corrain, G.; Gemmo, A.; Greenfield, P.; Hainaut, O.; Hook, R. N.; Tholen, D. J.; Blades, J. C.

    1994-01-01

    Images of the Pluto-Charon system were obtained with the Faint Object Camera (FOC) of the Hubble Space Telescope (HST) after the refurbishment of the telescope. The images are of superb quality, allowing the determination of radii, fluxes, and albedos. Attempts were made to improve the resolution of the already diffraction limited images by image restoration. These yielded indications of surface albedo distributions qualitatively consistent with models derived from observations of Pluto-Charon mutual eclipses.

  2. Hubble Space Telescope Images of the Ultraluminous Supernova Remnant Complex in NGC 6946

    Science.gov (United States)

    Blair, William P.; Fesen, Robert A.; Schlegel, Eric M.

    2001-03-01

    We present Hubble Space Telescope (HST) narrow-passband Hα and [S II] images and broadband continuum images of the region around an extremely luminous optical and X-ray supernova remnant complex in the spiral galaxy NGC 6946. These images, obtained with the PC1 CCD of the Wide Field Planetary Camera 2, show a circular, limb-brightened shell of diameter 0.35" [9 d/(5.1 Mpc) pc] superposed on the edge of a larger, lower surface brightness elliptical shell (1.4"×0.8", or ~=34 pc×20 pc). The HST images allow us to see that the [S II]:Hα ratio remains high across both shells, indicating that both are collisionally heated. A brightening of the Hα and [S II] line emission arises on the eastern side of the smaller shell, where it is apparently interacting with the western edge of the larger shell. Our HST V image includes the nebula's strong [O III] λ5007 emission in the blue wing of the filter, providing a glimpse at the [O III] nebular morphology. The smaller shell looks similar, but the extended structure looks sharper than in Hα and [S II] images, reminiscent of a cavity wall. The HST and ground-based continuum images show the brightest members of the underlying and adjacent stellar population, indicating the presence of massive OB stars in and near the region. A new optical ground-based spectrum confirms that the [N II]:Hα ratio is enhanced in the region, consistent with mass loss from massive stars. These data show an average ([S II] λλ6716, 6731):Hα ratio across both shells of ~1 and a mean electron density of ~400 cm-3, indicating preshock densities of order 10 cm-3. We interpret this nebular morphology and supporting information as an indication of multiple supernova explosions in relatively close temporal and spatial proximity. We discuss possible scenarios for this complex region and the reasons for its extreme luminosity. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is

  3. The universe in a mirror the saga of the Hubble Space Telescope and the visionaries who built it

    CERN Document Server

    Zimmerman, Robert

    2008-01-01

    The Hubble Space Telescope has produced the most stunning images of the cosmos humanity has ever seen. It has transformed our understanding of the universe around us, revealing new information about its age and evolution, the life cycle of stars, and the very existence of black holes, among other startling discoveries. But it took an amazing amount of work and perseverance to get the first space telescope up and running. The Universe in a Mirror tells the story of this telescope and the visionaries responsible for its extraordinary accomplishments. Robert Zimmerman takes readers beh

  4. Results of a Hubble Space Telescope Search for Natural Satellites of Dwarf Planet 1 Ceres

    Science.gov (United States)

    DeMario, Benjamin; Schmidt, Britney E.; Mutchler, Maximilian J.; Li, Jian-Yang; McFadden, Lucy Ann; McLean, Brian; Russell, Christopher T.

    2016-10-01

    In order to prepare for the arrival of the Dawn spacecraft at Ceres, a search for satellites was undertaken by the Hubble Space Telescope (HST) to enhance the mission science return and to ensure spacecraft safety. Previous satellite searches from ground-based telescopes have detected no satellites within Ceres' Hill sphere down to a size of 3 km (Gehrels et al. 1987) and early HST investigations searched to a limit of 1-2 km (Bieryla et al. 2011). The Wide Field Camera 3 (WFC3) on board the HST was used to image Ceres between 14 April - 28 April 2014. These images cover approximately the inner third of Ceres' Hill sphere, where the Hill sphere is the region surrounding Ceres where stable satellite orbits are possible. We performed a deep search for possible companions orbiting Ceres. No natural companions were located down to a diameter of 48 meters, over most of the Hill sphere to a distance of 205,000 km (434 Ceres radii) from the surface of Ceres. It was impossible to search all the way to the surface of Ceres because of scattered light, but at a distance of 2865 km (five Ceres radii), the search limit was determined to be 925 meters. The absence of a satellite around Ceres could, in the future, support more refined theories about satellite formation or capture mechanisms in the solar system.

  5. A New Method for Wide-Field Near-IR Imaging with the Hubble Space Telescope

    CERN Document Server

    Momcheva, Ivelina G; van der Wel, Arjen; Brammer, Gabriel B; Mackenty, John; Nelson, Erica J; Leja, Joel; Muzzin, Adam; Franx, Marijn

    2016-01-01

    We present a new technique for wide and shallow observations using the near-infrared channel of Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). Wide-field near-IR surveys with HST are generally inefficient, as guide star acquisitions make it impractical to observe more than one pointing per orbit. This limitation can be circumvented by guiding with gyros alone, which is possible as long as the telescope has three functional gyros. The method presented here allows us to observe mosaics of eight independent WFC3-IR pointings in a single orbit by utilizing the fact that HST drifts by only a very small amount in the 25 seconds between non-destructive reads of unguided exposures. By shifting the reads and treating them as independent exposures the full resolution of WFC3 can be restored. We use this "drift and shift" (DASH) method in the Cycle 23 COSMOS-DASH program, which will obtain 456 WFC3 $H_{160}$ pointings in 57 orbits, covering an area of 0.6 degree$^2$ in the COSMOS field down to $H_{160} ...

  6. Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

    CERN Document Server

    Wang, Xiaofeng; Filippenko, Alexei V; Aldering, Greg; Antilogus, Pierre; Arnett, David; Baade, Dietrich; Baron, Eddie; Barris, Brian J; Benetti, Stefano; Bouchet, Patrice; Burrows, Adam S; Canal, Ramon; Cappellaro, Enrico; Carlberg, Raymond; di Carlo, Elisa; Challis, Peter; Crotts, Arlin; Danziger, John I; Della Valle, Massimo; Jack, Dennis; Fink, Michael; Foley, Ryan J; Fransson, Claes; Gal-Yam, Avishay; Garnavich, Peter; Gerardy, Chris L; Goldhaber, Gerson; Hamuy, Mario; Hillebrandt, Wolfgang; Hoeflich, Peter A; Holland, Stephen T; Holz, Daniel E; Hughes, John P; Jeffery, David J; Jha, Saurabh W; Kasen, Dan; Khokhlov, Alexei M; Kirshner, Robert P; Knop, Robert; Kozma, Cecilia; Krisciunas, Kevin; Kromer, Markus; Lee, Brian C; Leibundgut, Bruno; Lentz, Eric J; Leonard, Douglas C; Lewin, Walter H G; Li, Weidong; Livio, Mario; Lundqvist, Peter; Maoz, Dan; Matheson, Thomas; Mazzali, Paolo; Meikle, Peter; Miknaitis, Gajus; Milne, Peter; Mochnacki, Stefan; Nomoto, Ken'Ichi; Nugent, Peter E; Oran, Elaine; Panagia, Nino; Patat, Ferdinando; Perlmutter, Saul; Phillips, Mark M; Pinto, Philip; Poznanski, Dovi; Pritchet, Christopher J; Reinecke, Martin; Riess, Adam; Ruiz-Lapuente, Pilar; Scalzo, Richard; Schlegel, Eric M; Schmidt, Brian; Siegrist, James; Soderberg, Alicia M; Sollerman, Jesper; Sonneborn, George; Spadafora, Anthony; Spyromilio, Jason; Sramek, Richard A; Starrfield, Sumner G; Strolger, Louis G; Suntzeff, Nicholas B; Thomas, Rollin; Tonry, John L; Tornambe, Amedeo; Truran, James W; Turatto, Massimo; Turner, Michael; Van Dyk, Schuyler D; Weiler, Kurt; Wheeler, J Craig; Wood-Vasey, Michael; Woosley, Stan; Yamaoka, Hitoshi; Zhang, Tianmeng

    2011-01-01

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This dataset provides unique spectral time series down to 2000 Angstrom. Significant diversity is seen in the near maximum-light spectra (~ 2000--3500 Angstrom) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in uvw1/F250W are found to correlate with the B-band light-curve shape parameter dm15(B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., ~0.4 mag versus ~0.2 mag for those with 0.8 3 sigma), being brighter than normal SNe Ia such as SN 2005cf by ~0.9 mag and ~2.0 mag in the uvw1/F250W and uvm2/F220W filters, respectively. We show th...

  7. Hubble Space Telescope observations of Europa in and out of eclipse

    Science.gov (United States)

    Sparks, W.B.; McGrath, M.; Hand, K.; Ford, H.C.; Geissler, P.; Hough, J.H.; Turner, E.L.; Chyba, C.F.; Carlson, R.; Turnbull, M.

    2010-01-01

    Europa is a prime target for astrobiology and has been prioritized as the next target for a National Aeronautics and Space Administration flagship mission. It is important, therefore, that we advance our understanding of Europa, its ocean and physical environment as much as possible. Here, we describe observations of Europa obtained during its orbital eclipse by Jupiter using the Hubble Space Telescope. We obtained Advanced Camera for Surveys Solar Blind Channel far ultraviolet low-resolution spectra that show oxygen line emission both in and out of eclipse. We also used the Wide-Field and Planetary Camera-2 and searched for broad-band optical emission from fluorescence of the surface material, arising from the very high level of incident energetic particle radiation on ices and potentially organic substances. The high-energy particle radiation at the surface of Europa is extremely intense and is responsible for the production of a tenuous oxygen atmosphere and associated FUV line emission. Approximately 50% of the oxygen emission lasts at least a few hours into the eclipse. We discuss the detection limits of the optical emission, which allow us to estimate the fraction of incident energy reradiated at optical wavelengths, through electron-excited emission, Cherenkov radiation in the ice and fluorescent processes. ?? 2010 Cambridge University Press.

  8. Attitude-dependent launch window analysis for the Hubble Space Telescope Mission

    Science.gov (United States)

    Lenio, James A.

    1990-01-01

    Launch window analysis for Space Shuttle missions determines the launch times which will ensure that all payload and Shuttle requirements for the mission are met. Attitude and pointing analysis determines Shuttle Orbiter attitudes that meet various communication, viewing, and thermal requirements for the Orbiter and its payloads. Historically, launch window analysis and attitude and pointing analysis for Shuttle missions have been done separately, without directly influencing each other. However, methods have been developed to consider simultaneously dependencies between launch window and attitude and pointing requirements if they arise. These methods were developed from the launch window analysis for STS-31, the Hubble Space Telescope (HST) deployment mission. To release the HST, the Orbiter attitude had to remain inertially fixed while pointing the HST at the Sun. The Orbiter release attitude and the HST release time were determined from the position of the Sun and varied with launch time and launch date. The launch window analysis for STS-31 centered on how to determine the range of launch times for a given launch date that would allow the Shuttle to release the HST and simultaneously satisfy communication, attitude, and lighting requirements for the deployment operations. Discussed here are how the HST deployment requirements determined the launch window and how the Orbiter release attitude affected the launch window.

  9. Accretion disk reverberation with Hubble Space Telescope observations of NGC 4593

    Science.gov (United States)

    Cackett, Edward; McHardy, Ian; Horne, Keith D.; Goad, Michael; Edelson, Rick; Korista, Kirk T.; Chiang, Chia-Ying

    2017-08-01

    Irradiation of the accretion disk by X-ray/EUV photons should lead to wavelength-dependent UV/optical continuum time lags as the hotter, inner parts of the disk will see the variable irradiating flux before the cooler, outer parts of the disk. Recently, there has been a significant improvement in wavelength-dependent lag measurements from high-cadence monitoring and a picture is emerging that the accretion disk sizes are a factor of 2 - 3 larger than predicted by the standard disk model. We obtained Hubble Space Telescope spectroscopy of NGC 4593 as part of a larger multi-wavelength reverberation mapping campaign including monitoring by Swift and Kepler. From 2016 July 12 to 2016 August 6 we performed 26 observations with an approximately daily cadence using the Space Telescope Imaging Spectrograph. The spectra cover a nearly continuous wavelength range from approximately 1150 - 10000Å. The continuum is significantly variable at all wavelengths, with variations at 1150Å leading variations at 8950Å by approximately 1.2 days. In the scenario where X-rays or EUV photons drive variability in the accretion disk the time lags should follow λ4/3. Here, we see a significant deviation from this around the Balmer jump, indicating a large contribution to the lags from diffuse continuum emission in the broad line region. However, even when taking this diffuse continuum lag into account, we still find that the accretion disk lags are a factor of about 3 larger than expected from the standard disk model.

  10. THE HUBBLE SPACE TELESCOPE TREASURY PROGRAM ON THE ORION NEBULA CLUSTER {sup ,}

    Energy Technology Data Exchange (ETDEWEB)

    Robberto, M.; Soderblom, D. R.; Bergeron, E.; Kozhurina-Platais, V.; Makidon, R. B.; McCullough, P. R.; McMaster, M.; Panagia, N.; Reid, I. N.; Levay, Z.; Frattare, L. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Da Rio, N.; Andersen, M. [European Space Agency, Keplerlaan 1, 2200-AG Noordwijk (Netherlands); O' Dell, C. R.; Stassun, K. G. [Department of Physics and Astronomy, Vanderbilt University, 6301 Stevenson Center, Nashville, TN 37235 (United States); Simon, M. [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States); Feigelson, E. D. [Department of Astronomy and Astrophysics, Pennsylvania State University, 518 Davey Lab, University Park, PA 16802 (United States); Stauffer, J. R. [Spitzer Science Center, California Institute of Technology 314-6, Pasadena, CA 91125 (United States); Meyer, M.; Reggiani, M., E-mail: robberto@stsci.edu [ETH Zuerich, Institut fuer Astronomie, Wolfgang-Pauli-Strasse 27, CH-8093 Zuerich (Switzerland); and others

    2013-07-01

    The Hubble Space Telescope (HST) Treasury Program on the Orion Nebula Cluster (ONC) has used 104 orbits of HST time to image the Great Orion Nebula region with the Advanced Camera for Surveys (ACS), the Wide-Field/Planetary Camera 2 (WFPC2), and the Near-Infrared Camera and Multi-Object Spectrograph (NICMOS) instrument in 11 filters ranging from the U band to the H band equivalent of HST. The program has been intended to perform the definitive study of the stellar component of the ONC at visible wavelengths, addressing key questions like the cluster initial mass function, age spread, mass accretion, binarity, and cirumstellar disk evolution. The scanning pattern allowed us to cover a contiguous field of approximately 600 arcmin{sup 2} with both ACS and WFPC2, with a typical exposure time of approximately 11 minutes per ACS filter, corresponding to a point source depth AB(F435W) = 25.8 and AB(F775W) = 25.2 with 0.2 mag of photometric error. We describe the observations, data reduction, and data products, including images, source catalogs, and tools for quick look preview. In particular, we provide ACS photometry for 3399 stars, most of them detected at multiple epochs; WFPC2 photometry for 1643 stars, 1021 of them detected in the U band; and NICMOS JH photometry for 2116 stars. We summarize the early science results that have been presented in a number of papers. The final set of images and the photometric catalogs are publicly available through the archive as High Level Science Products at the STScI Multimission Archive hosted by the Space Telescope Science Institute.

  11. Overview of EVA PRA for TPS Repair for Hubble Space Telescope Servicing Mission

    Science.gov (United States)

    Bigler, Mark; Duncan, Gary; Roeschel, Eduardo; Canga, Michael

    2010-01-01

    Following the Columbia accident in 2003, NASA developed techniques to repair the Thermal Protection System (TPS) in the event of damage to the TPS as one of several actions to reduce the risk to future flights from ascent debris, micro-meteoroid and/or orbital debris (MMOD). Other actions to help reduce the risk include improved inspection techniques, reduced shedding of debris from the External Tank and ability to rescue the crew with a launch on need vehicle. For the Hubble Space Telescope (HST) Servicing Mission the crew rescue capability was limited by the inability to safe haven on the International Space Station (ISS), resulting in a greater reliance on the repair capability. Therefore it was desirable to have an idea of the risk associated with conducting a repair, where the repair would have to be conducted using an Extra-Vehicular Activity (EVA). Previously, focused analyses had been conducted to quantify the risk associated with certain aspects of an EVA, for example the EVA Mobility Unit (EMU) or Space Suit; however, the analyses were somewhat limited in scope. A complete integrated model of an EVA which could quantify the risk associated with all of the major components of an EVA had never been done before. It was desired to have a complete integrated model to be able to assess the risks associated with an EVA to support the Space Shuttle Program (SSP) in making risk informed decisions. In the case of the HST Servicing Mission, this model was developed to assess specifically the risks associated with performing a TPS repair EVA. This paper provides an overview of the model that was developed to support the HST mission in the event of TPS damage. The HST Servicing Mission was successfully completed on May 24th 2009 with no critical TPS damage; therefore the model was not required for real-time mission support. However, it laid the foundation upon which future EVA quantitative risk assessments could be based.

  12. Hubble Space Telescope Near-IR Transmission Spectroscopy of the Super-Earth HD 97658b

    CERN Document Server

    Knutson, Heather A; Kreidberg, Laura; Kempton, Eliza M -R; McCullough, P R; Fortney, Jonathan J; Bean, Jacob L; Gillon, Michael; Homeier, Derek; Howard, Andrew W

    2014-01-01

    Recent results from the Kepler mission indicate that super-Earths (planets with masses between 1-10 times that of the Earth) are the most common kind of planet around nearby Sun-like stars. These planets have no direct solar system analogue, and are currently one of the least well-understood classes of extrasolar planets. Many super-Earths have average densities that are consistent with a broad range of bulk compositions, including both water-dominated worlds and rocky planets covered by a thick hydrogen and helium atmosphere. Measurements of the transmission spectra of these planets offer the opportunity to resolve this degeneracy by directly constraining the scale heights and corresponding mean molecular weights of their atmospheres. We present Hubble Space Telescope near-infrared spectroscopy of two transits of the newly discovered transiting super-Earth HD 97658b. We use the Wide Field Camera 3's scanning mode to measure the wavelength-dependent transit depth in thirty individual bandpasses. Our averaged ...

  13. Rotation of Jets from Young Stars: New Clues from the Hubble Space Telescope Imaging Spectrograph

    CERN Document Server

    Coffey, D; Woitas, J; Ray, T P; Eislöffel, J; Coffey, Deirdre; Bacciotti, Francesca; Woitas, Jens; Ray, Thomas P.; Eisl\\"offel, Jochen

    2004-01-01

    We report findings from the first set of data in a current survey to establish conclusively whether jets from young stars rotate. We observed the bi-polar jets from the T Tauri stars TH28 and RW Aur, and the blue-shifted jet from T Tauri star LkH$\\alpha$321, using the Hubble Space Telescope Imaging Spectrograph (HST/STIS). Forbidden emission lines (FELs) show distinct and systematic velocity asymmetries of 10 -- 25 (+/- 5) km/s at a distance of 0".3 from the source, representing a (projected) distance of ~ 40 AU along the jet in the case of RW Aur, ~ 50 AU for TH28, and 165 AU in the case of LkH$\\alpha$321. These velocity asymmetries are interpreted as rotation in the initial portion of the jet where it is accelerated and collimated. For the bi-polar jets, both lobes appear to rotate in the same direction. Values obtained were in agreement with the predictions of MHD disk-wind models (Bacciotti et al 2002, Anderson et al 2003, Dougados et al 2003, Pesenti et al 2003). Finally, we determine, from derived toroi...

  14. T Tauri Jet Physics Resolved Near The Launching Region with the Hubble Space Telescope

    CERN Document Server

    Coffey, Deirdre; Podio, Linda

    2008-01-01

    We present an analysis of the gas physics at the base of jets from five T Tauri stars based on high angular resolution optical spectra, using the Hubble Space Telescope Imaging Spectrograph (HST/STIS). The spectra refer to a region within 100 AU of the star, i.e. where the collimation of the jet has just taken place. We form PV images of the line ratios to get a global picture of the flow excitation. We then apply a specialised diagnostic technique to find the electron density, ionisation fraction, electron temperature and total density. Our results are in the form of PV maps of the obtained quantities, in which the gas behaviour is resolved as a function of both radial velocity and distance from the jet axis. They highlight a number of interesting physical features of the jet collimation region, including regions of extremely high density, asymmetries with respect to the axis, and possible shock signatures. Finally, we estimate the jet mass and angular momentum outflow rates, both of which are fundamental pa...

  15. Morphology and time variation of the Jovian Far UV aurora: Hubble Space Telescope observations

    Science.gov (United States)

    Gerard, Jean-Claude; Dols, Vincent; Paresce, Francesco; Prange, Renee

    1993-01-01

    High spatial resolution images of the north polar region of Jupiter have been obtained with the Faint Object Camera (FOC) on board the Hubble Space Telescope (HST). The first set of two images collected 87 min apart in February 1992 shows a bright (approximately or equal to 180 kR) emission superimposed on the background in rotation with the planet. Both Ly alpha images show common regions of enhanced emission but differences are also observed, possibly due to temporal variations. The second group of images obtained on June 23 and 26, 1992 isolates a spectral region near 153 nm dominated by the H2 Lyman bands and continuum. Both pictures exhibit a narrow arc structure fitting the L = 30 magnetotail field line footprint in the morning sector and a broader diffuse aurora in the afternoon. They show no indication of an evening twilight enhancement. Although the central meridian longitudes were similar, significant differences are seen in the two exposures, especially in the region of diffuse emission, and interpreted as signatures of temporal variations. The total power radiated in the H2 bands is approximately or equal to 2 x 10(exp 12) W, in agreement with previous UV spectrometer observations. The high local H2 emission rates (approximately 450 kR) imply a particle precipitation carrying an energy flux of about 5 x 10(exp -2) W/sq m.

  16. Hubble Space Telescope Constraints on the Winds and Astrospheres of Red Giant Stars

    CERN Document Server

    Wood, Brian E; Harper, Graham M

    2016-01-01

    We report on an ultraviolet spectroscopic survey of red giants observed by the Hubble Space Telescope, focusing on spectra of the Mg II h & k lines near 2800 A in order to study stellar chromospheric emission, winds, and astrospheric absorption. We focus on spectral types between K2 III and M5 III, a spectral type range with stars that are noncoronal, but possessing strong, chromospheric winds. We find a very tight relation between Mg II surface flux and photospheric temperature, supporting the notion that all K2-M5 III stars are emitting at a basal flux level. Wind velocities (V_w) are generally found to decrease with spectral type, with V_w decreasing from ~40 km/s at K2 III to ~20 km/s at M5 III. We find two new detections of astrospheric absorption, for Sigma Pup (K5 III) and Gamma Eri (M1 III). This absorption signature had previously only been detected for Alpha Tau (K5 III). For the three astrospheric detections the temperature of the wind after the termination shock correlates with V_w, but is low...

  17. The Hubble Space Telescope Cluster Supernova Survey: VI. The Volumetric Type Ia Supernova Rate

    CERN Document Server

    Barbary, K; Amanullah, R; Brodwin, M; Connolly, N; Dawson, K S; Doi, M; Eisenhardt, P; Faccioli, L; Fadeyev, V; Fakhouri, H K; Fruchter, A S; Gilbank, D G; Gladders, M D; Goldhaber, G; Goobar, A; Hattori, T; Hsiao, E; Huang, X; Ihara, Y; Kashikawa, N; Koester, B; Konishi, K; Kowalski, M; Lidman, C; Lubin, L; Meyers, J; Morokuma, T; Oda, T; Panagia, N; Perlmutter, S; Postman, M; Ripoche, P; Rosati, P; Rubin, D; Schlegel, D J; Spadafora, A L; Stanford, S A; Strovink, M; Suzuki, N; Takanashi, N; Tokita, K; Yasuda, N

    2011-01-01

    We present a measurement of the volumetric Type Ia supernova (SN Ia) rate out to z ~ 1.6 from the Hubble Space Telescope Cluster Supernova Survey. In observations spanning 189 orbits with the Advanced Camera for Surveys we discovered 29 SNe, of which approximately 20 are SNe Ia. Twelve of these SNe Ia are located in the foregrounds and backgrounds of the clusters targeted in the survey. Using these new data, we derive the volumetric SN Ia rate in four broad redshift bins, finding results consistent with previous measurements at z > 1 and strengthening the case for a SN Ia rate that is equal to or greater than ~0.6 x 10^-4/yr/Mpc^3 at z ~ 1 and flattening out at higher redshift. We provide SN candidates and efficiency calculations in a form that makes it easy to rebin and combine these results with other measurements for increased statistics. Finally, we compare the assumptions about host-galaxy dust extinction used in different high-redshift rate measurements, finding that different assumptions may induce sig...

  18. Discovery of an Unusual Optical Transient with the Hubble Space Telescope

    CERN Document Server

    Barbary, K; Tokita, K; Aldering, G; Amanullah, R; Connolly, N V; Doi, M; Faccioli, L; Fadeev, V; Fruchter, A S; Goldhaber, G; Goobar, A; Gude, A; Huang, X; Ihara, Y; Konishi, K; Kowalski, M; Lidman, C; Meyers, J; Morokuma, T; Nugent, P; Perlmutter, S; Rubin, D; Schlegel, D; Spadafora, A L; Suzuki, N; Swift, H K; Takanashi, N; Thomas, R C; Yasuda, N; Project, for the Supernova Cosmology

    2008-01-01

    We present observations of SCP 06F6, an unusual optical transient discovered during the Hubble Space Telescope Cluster Supernova Survey. The transient brightened over a period of ~100 days, reached a peak magnitude of ~21.0 in both i_775 and z_850, and then declined over a similar timescale. There is no host galaxy or progenitor star detected at the location of the transient to a 3 sigma upper limit of i_775 = 26.4 and z_850 = 26.1, giving a corresponding lower limit on the flux increase of a factor of ~120. Multiple spectra show five broad absorption bands between 4100 AA and 6500 AA and a mostly featureless continuum longward of 6500 AA. The shape of the lightcurve is inconsistent with microlensing. The transient's spectrum, in addition to being inconsistent with all known supernova types, is not matched to any spectrum in the Sloan Digital Sky Survey (SDSS) database. We suggest that the transient may be one of a new class.

  19. Hubble Space Telescope Observations of cD Galaxies and their Globular Cluster Systems

    CERN Document Server

    Jordan, A; West, M J; Marzke, R O; Minniti, D; Rejkuba, M; Jordan, Andres; Cote, Patrick; West, Michael J.; Marzke, Ronald O.; Minniti, Dante; Rejkuba, Marina

    2004-01-01

    We have used WFPC2 on the Hubble Space Telescope to obtain F450W and F814W images of four cD galaxies (NGC 541 in Abell 194, NGC 2832 in Abell 779, NGC 4839 in Abell 1656 and NGC 7768 in Abell 2666) in the range 5400 < cz < 8100 km s^{-1}. For NGC 541, the HST data are supplemented by ground-based B and I images obtained with the FORS1 on the VLT. We present surface brightness and color profiles for each of the four galaxies, confirming their classification as cD galaxies. Isophotal analyses reveal the presence of subarcsecond-scale dust disks in the nuclei of NGC 541 and NGC 7768. Despite the extreme nature of these galaxies in terms of spatial extent and luminosity, our analysis of their globular cluster systems reveals no anomalies in terms of specific frequencies, metallicity gradients, average metallicities, or the metallicity offset between the globulars and the host galaxy. We show that the latter offset appears roughly constant at \\Delta [Fe/H] ~ 0.8 dex for early-type galaxies spanning a lumino...

  20. 3D-HST: A wide-field grism spectroscopic survey with the Hubble Space Telescope

    CERN Document Server

    Brammer, Gabriel; Franx, Marijn; Fumagalli, Mattia; Patel, Shannon; Rix, Hans-Walter; Skelton, Rosalind; Kriek, Mariska; Nelson, Erica; Schmidt, Kasper; Bezanson, Rachel; da Cunha, Elisabete; Erb, Dawn; Fan, Xiaohui; Schreiber, Natascha Förster; Illingworth, Garth; Labbé, Ivo; Leja, Joel; Lundgren, Britt; Magee, Dan; Marchesini, Danilo; McCarthy, Patrick; Momcheva, Ivelina; Muzzin, Adam; Quadri, Ryan; Steidel, Charles; Tal, Tomer; Wake, David; Whitaker, Katherine; Williams, Anna

    2012-01-01

    We present 3D-HST, a near-infrared spectroscopic Treasury program with the Hubble Space Telescope for studying the processes that shape galaxies in the distant Universe. 3D-HST provides rest-frame optical spectra for a sample of ~7000 galaxies at 1

  1. The FUV detector for the cosmic origins spectrograph on the Hubble Space Telescope

    Science.gov (United States)

    Vallerga, J.; Zaninovich, J.; Welsh, B.; Siegmund, O.; McPhate, J.; Hull, J.; Gaines, G.; Buzasi, D.

    2002-01-01

    The Cosmic Origins Spectrograph (COS) is a high throughput spectrometer that will be placed on the Hubble Space Telescope (HST) during the last servicing mission in the year 2003. COS will be the most sensitive UV spectrograph ever flown aboard HST and will investigate such fundamental issues as the ionization and baryon content of the intergalactic medium and the origin of large-scale structure of the Universe. The driving design goal for COS is to maximize throughput at a moderate spectral resolution of />20,000 using optics with very few reflections and detectors with high quantum efficiency in two bandpass channels: FUV (1150-1775Å) and NUV (1750-3200Å). The COS FUV detector, a windowless microchannel plate (MCP) detector, consists of two segments each 85mm×10mm concatenated end to end with a 9mm gap between them. The design is based on the Far Ultraviolet Spectroscopic Explorer detectors with identical format and front surface radius of curvature that matches the grating focal plane of the spectrograph. However, enhancements have been made in the design and fabrication of the MCPs, the photocathode, the delay line anode and the readout electronics. We discuss these design enhancements and their significance.

  2. HUBBLE SPACE TELESCOPE SPECTROSCOPY OF BROWN DWARFS DISCOVERED WITH THE WIDE-FIELD INFRARED SURVEY EXPLORER

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Adam C.; Cushing, Michael C. [Department of Physics and Astronomy, University of Toledo, 2801 W. Bancroft St., Toledo, OH 43606 (United States); Kirkpatrick, J. Davy; Gelino, Christopher R. [Infrared Processing and Analysis Center, MS 100-22, California Institute of Technology, Pasadena, CA 91125 (United States); Mace, Gregory N.; Wright, Edward L. [Department of Physics and Astronomy, UCLA, 430 Portola Plaza, Box 951547, Los Angeles, CA 90095-1547 (United States); Eisenhardt, Peter R. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109 (United States); Skrutskie, M. F. [Department of Astronomy, University of Virginia, 530 McCormick Road, Charlottesville, VA 22904 (United States); Griffith, Roger L. [Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States); Marsh, Kenneth A., E-mail: Adam.Schneider@Utoledo.edu [School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA (United Kingdom)

    2015-05-10

    We present a sample of brown dwarfs identified with the Wide-field Infrared Survey Explorer (WISE) for which we have obtained Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) near-infrared grism spectroscopy. The sample (22 in total) was observed with the G141 grism covering 1.10–1.70 μm, while 15 were also observed with the G102 grism, which covers 0.90–1.10 μm. The additional wavelength coverage provided by the G102 grism allows us to (1) search for spectroscopic features predicted to emerge at low effective temperatures (e.g.,ammonia bands) and (2) construct a smooth spectral sequence across the T/Y boundary. We find no evidence of absorption due to ammonia in the G102 spectra. Six of these brown dwarfs are new discoveries, three of which are found to have spectral types of T8 or T9. The remaining three, WISE J082507.35+280548.5 (Y0.5), WISE J120604.38+840110.6 (Y0), and WISE J235402.77+024015.0 (Y1), are the 19th, 20th, and 21st spectroscopically confirmed Y dwarfs to date. We also present HST grism spectroscopy and reevaluate the spectral types of five brown dwarfs for which spectral types have been determined previously using other instruments.

  3. Hubble Space Telescope search for the transit of the Earth-mass exoplanet Alpha Centauri Bb

    CERN Document Server

    Demory, Brice-Olivier; Queloz, Didier; Seager, Sara; Gilliland, Ronald; Chaplin, William J; Proffitt, Charles; Gillon, Michael; Guenther, Maximilian N; Benneke, Bjoern; Dumusque, Xavier; Lovis, Christophe; Pepe, Francesco; Segransan, Damien; Triaud, Amaury; Udry, Stephane

    2015-01-01

    Results from exoplanet surveys indicate that small planets (super-Earth size and below) are abundant in our Galaxy. However, little is known about their interiors and atmospheres. There is therefore a need to find small planets transiting bright stars, which would enable a detailed characterisation of this population of objects. We present the results of a search for the transit of the Earth-mass exoplanet Alpha Centauri Bb with the Hubble Space Telescope (HST). We observed Alpha Centauri B twice in 2013 and 2014 for a total of 40 hours. We achieve a precision of 115 ppm per 6-s exposure time in a highly-saturated regime, which is found to be consistent across HST orbits. We rule out the transiting nature of Alpha Centauri Bb with the orbital parameters published in the literature at 96.6% confidence. We find in our data a single transit-like event that could be associated to another Earth-size planet in the system, on a longer period orbit. Our program demonstrates the ability of HST to obtain consistent, hi...

  4. Hubble Space Telescope/Advanced Camera for Surveys Confirmation of the Dark Substructure in A520

    CERN Document Server

    Jee, M James; Mahdavi, Andisheh; Babul, Arif

    2014-01-01

    We present the results from a weak gravitational lensing study of the merging cluster A520 based on the analysis of Hubble Space Telescope/Advanced Camera for Surveys (ACS) data. The excellent data quality allows us to reach a mean number density of source galaxies of ~109 per sq. arcmin, which improves both resolution and significance of the mass reconstruction compared to a previous study based on Wide Field Planetary Camera 2 (WFPC2) images. We take care in removing instrumental effects such as the trailing of charge due to radiation damage of the ACS detector and the position-dependent point spread function (PSF). This new ACS analysis confirms the previous claims that a substantial amount of dark mass is present between two luminous subclusters. We examine the distribution of cluster galaxies and observe very little light at this location. We find that the centroid of the dark peak in the current ACS analysis is offset to the southwest by ~1 arcmin with respect to the centroid from the WFPC2 analysis. In...

  5. A Study of Gravitational Lens Chromaticity with the Hubble Space Telescope

    CERN Document Server

    Muñoz, José A; Kochanek, Christopher S; Falco, Emilio; Mosquera, Ana María

    2011-01-01

    We report Hubble Space Telescope observations of 6 gravitational lenses with the Advanced Camera for Surveys. We measured the flux ratios between the lensed images in 6 filters from 8140\\AA\\ to 2200\\AA. In 3 of the systems, HE0512$-$3329, B1600+434, and H1413+117, we were able to construct UV extinction curves partially overlapping the 2175\\AA\\ feature and characterize the properties of the dust relative to the Galaxy and the Magellanic Clouds. In HE1104$-$1804 we detect chromatic microlensing and use it to study the physical properties of the quasar accretion disk. For a Gaussian model of the disk $\\exp(-r^2/2 r_s^2)$, scaling with wavelength as $r_s \\propto \\lambda^p$, we estimate $r_s(\\lambda3363)=4^{+4}_{-2}$ ($7\\pm 4$) light-days and $p=1.1\\pm 0.6$ ($1.0\\pm 0.6$) for a logarithmic (linear) prior on $r_s$. The remaining two systems, FBQ0951+2635 and SBS1520+530, yielded no useful estimates of extinction or chromatic microlensing.

  6. Hunting for accretors towards the bulge with the Chandra and Hubble Space Telescopes

    Science.gov (United States)

    Howard, Brittany; Aufdemberge, Emily; Hong, JaeSub; Clarkson, William I.; Van Den Berg, Maureen; Sahu, Kailash C.; Grindlay, Jonanthan; Rich, Robert Michael; Calamida, Annalisa

    2017-01-01

    We are undertaking a deep X-ray/optical observational campaign of a well-studied low-extinction region towards the Galactic Bulge. Crucially, we have chosen a field for which very high-quality proper motions already exist from Hubble Space Telescope (HST) observations (or can be produced from a combination of archival and new observations covering much of the large Chandra ACIS-I field of view), allowing kinematic population membership constraints for X-ray point sources. While the ultimate scientific goal is to provide a new constraint on bulge formation models by tracing the accreting binary population that can be kinematically identified with the bulge, a large number of science investigations will ultimately be enabled by this initiative.Here we report on our search for accreting binaries within the Sagittarius Window. The deep Chandra observations provide a rich catalog of X-ray point sources, while the new HST observations allow a sensitive search for Hα emission-line objects including the accreting binaries we seek. We present the techniques used to uncover accretors, and outline progress towards a catalog of X-ray point sources with kinematic and Hα identifications.

  7. Hubble Space Telescope Observations of Active Asteroid 324P/La Sagra

    CERN Document Server

    Jewitt, David; Weaver, Harold; Mutchler, Max; Li, Jing; Larson, Stephen

    2016-01-01

    Hubble Space Telescope observations of active asteroid 324P/La Sagra near perihelion show continued mass loss consistent with the sublimation of near-surface ice. Isophotes of the coma measured from a vantage point below the orbital plane are best matched by steady emission of particles having a nominal size $a \\sim$ 100 $\\mu$m. The inferred rate of mass loss, $dM_d/dt \\sim$0.2 kg s$^{-1}$, can be supplied by sublimation of water ice in thermal equilibrium with sunlight from an area as small as 930 m$^2$, corresponding to about 0.2\\% of the nucleus surface. Observations taken from a vantage point only 0.6\\degr~from the orbital plane of 324P set a limit to the velocity of ejection of dust in the direction perpendicular to the plane, $V_{\\perp} <$ 1 m s$^{-1}$. Short-term photometric variations of the near-nucleus region, if related to rotation of the underlying nucleus, rule out periods $\\le$ 3.8 hr and suggest that rotation probably does not play a central role in driving the observed mass loss. We estimat...

  8. HUBBLE SPACE TELESCOPE REVEALS MULTIPLE SUB-GIANT BRANCH IN EIGHT GLOBULAR CLUSTERS

    Energy Technology Data Exchange (ETDEWEB)

    Piotto, G.; Nascimbeni, V. [Dipartimento di Astronomia, Universita di Padova, Vicolo dell' Osservatorio 3, I-35122 Padova (Italy); Milone, A. P.; Aparicio, A. [Instituto de Astrofisica de Canarias, E-38200 La Laguna, Tenerife, Canary Islands (Spain); Anderson, J.; Bellini, A. [Space Telescope Science Institute, 3800 San Martin Drive, Baltimore, MD 21218 (United States); Bedin, L. R. [INAF-Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Cassisi, S. [INAF-Osservatorio Astronomico di Collurania, via Mentore Maggini, I-64100 Teramo (Italy); Marino, A. F., E-mail: giampaolo.piotto@unipd.it, E-mail: luigi.bedin@oapd.inaf.it, E-mail: milone@iac.es, E-mail: aparicio@iac.es, E-mail: jayander@stsci.edu, E-mail: bellini@stsci.edu, E-mail: cassisi@oa-teramo.inaf.it, E-mail: amarino@MPA-Garching.MPG.DE [Max Planck Institute for Astrophysics, Postfach 1317, D-85741 Garching (Germany)

    2012-11-20

    In the last few years many globular clusters (GCs) have revealed complex color-magnitude diagrams, with the presence of multiple main sequences (MSs), broad or multiple sub-giant branches (SGBs) and MS turnoffs, and broad or split red giant branches (RGBs). After a careful correction for differential reddening, high-accuracy photometry with the Hubble Space Telescope (HST) presented in this paper reveals a broadened or even split SGB in five additional Milky Way GCs: NGC 362, NGC 5286, NGC 6656, NGC 6715, and NGC 7089. In addition, we confirm (with new and archival HST data) the presence of a split SGB in 47 Tuc, NGC 1851, and NGC 6388. The fraction of faint SGB stars with respect to the entire SGB population varies from one cluster to another and ranges from {approx}0.03 for NGC 362 to {approx}0.50 for NGC 6715. The average magnitude difference between the bright SGB and the faint SGB is almost the same at different wavelengths. This peculiarity is consistent with the presence of two groups of stars with either an age difference of about 1-2 Gyr or a significant difference in their overall C+N+O content.

  9. Study of the young stellar population of NGC 4214 using the Hubble Space Telescope

    CERN Document Server

    Ubeda, Leonardo

    2007-01-01

    We present an original study of the dwarf starburst galaxy NGC 4214. We use archival optical and UV images obtained with WFPC2 and STIS on-board the Hubble Space Telescope. We explain the process followed to obtain high-quality photometry and astrometry of the stellar and cluster populations of this galaxy. We describe the procedure used to transform magnitudes and colours into physical parameters using spectral energy distributions. We analyze several aspects of the astrophysics of NGC 4214: we briefly describe the stellar populations in its inner structure with emphasis in the determination of the ratio of blue-to-red supergiants. We study the stellar extinction and we find it consistent with previous studies of the nebular extinction. The extinction associated to the stellar population is found to be rather low (E(B-V) < 0.1 mag). We make a complete research of the initial mass function (IMF) of the stars with masses between 20 and 100 Mo using a photometric method. We find that this dwarf galaxy has a ...

  10. The Hubble Space Telescope Survey of BL Lacertae Objects. IV. Infrared Imaging of Host Galaxies

    Science.gov (United States)

    Scarpa, Riccardo; Urry, C. Megan; Padovani, Paolo; Calzetti, Daniela; O'Dowd, Matthew

    2000-11-01

    The Hubble Space Telescope NICMOS Camera 2 was used for H-band imaging of 12 BL Lacertae objects taken from the larger sample observed with the WFPC2 in the R band by Urry and coworkers and Scarpa and coworkers. Ten of the 12 BL Lacs are clearly resolved, and the detected host galaxies are large, bright ellipticals with average absolute magnitude =-26.2+/-0.45 mag and effective radius =10+/-5 kpc. The rest-frame integrated color of the host galaxies is on average =2.3+/-0.3, consistent with the value for both radio galaxies and normal, nonactive elliptical galaxies and indicating that the dominant stellar population is old. The host galaxies tend to be bluer in their outer regions than in their cores, with average color gradient Δ(R-H)/Δlogr=-0.2 mag, again consistent with results for normal nonactive elliptical galaxies. The infrared Kormendy relation, derived for the first time for BL Lac host galaxies, is μe=3.8logre+14.8, fully in agreement with the relation for normal ellipticals. The close similarity between BL Lac host galaxies and normal ellipticals suggests that the active nucleus has surprisingly little effect on the host galaxy. This supports a picture in which all elliptical galaxies harbor black holes that can be actively accreting for some fraction of their lifetime.

  11. Hubble Space Telescope observations of an extraordinary flare in the M87 jet

    CERN Document Server

    Madrid, Juan P

    2009-01-01

    HST-1, a knot along the M87 jet located 0.85 arcsec from the nucleus of the galaxy has experienced dramatic and unexpected flaring activity since early 2000. We present analysis of Hubble Space Telescope Near-Ultraviolet (NUV) imaging of the M87 jet from 1999 May to 2006 December that reveals that the NUV intensity of HST-1 has increased 90 times over its quiescent level and outshines the core of the galaxy. The NUV light curve that we derive is synchronous with the light curves derived in other wavebands. The correlation of X-ray and NUV light curves during the HST-1 flare confirms the synchrotron origin of the X-ray emission in the M87 jet. The outburst observed in HST-1 is at odds with the common definition of AGN variability usually linked to blazars and originating in close proximity of the central black hole. In fact, the M87 jet is not aligned with our line of sight and HST-1 is located at one million Schwarzchild radii from the super-massive black hole in the core of the galaxy.

  12. The Hubble Space Telescope Treasury Program on the Orion Nebula Cluster

    CERN Document Server

    Robberto, M; Bergeron, E; Kozhurina-Platais, V; Makidon, R B; McCullough, P R; McMaster, M; Panagia, N; Reid, I N; Levay, Z; Frattare, L; Da Rio, N; Andersen, M; O'Dell, C R; Stassun, K G; Simon, M; Feigelson, E D; Stauffer, J R; Meyer, M; Reggiani, M; Krist, J; Manara, C F; Romaniello, M; Hillenbrand, L A; Ricci, L; Palla, F; Najita, J R; Ananna, T T; Scandariato, G; Smith, K

    2013-01-01

    The Hubble Space Telescope (HST) Treasury Program on the Orion Nebula Cluster has used 104 orbits of HST time to image the Great Orion Nebula region with the Advanced Camera for Surveys (ACS), the Wide-Field/Planetary Camera 2 (WFPC2) and the Near Infrared Camera and Multi Object Spectrograph (NICMOS) instruments in 11 filters ranging from the U-band to the H-band equivalent of HST. The program has been intended to perform the definitive study of the stellar component of the ONC at visible wavelengths, addressing key questions like the cluster IMF, age spread, mass accretion, binarity and cirumstellar disk evolution. The scanning pattern allowed to cover a contiguous field of approximately 600 square arcminutes with both ACS and WFPC2, with a typical exposure time of approximately 11 minutes per ACS filter, corresponding to a point source depth AB(F435W) = 25.8 and AB(F775W)=25.2 with 0.2 magnitudes of photometric error. We describe the observations, data reduction and data products, including images, source ...

  13. A LYMAN BREAK GALAXY IN THE EPOCH OF REIONIZATION FROM HUBBLE SPACE TELESCOPE GRISM SPECTROSCOPY

    Energy Technology Data Exchange (ETDEWEB)

    Rhoads, James E.; Malhotra, Sangeeta; Cohen, Seth; Zheng Zhenya [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Dickinson, Mark [National Optical Astronomy Observatory, Tucson, AZ (United States); Pirzkal, Norbert; Grogin, Norman; Koekemoer, Anton; Peth, Michael A. [Space Telescope Science Institute, Baltimore, MD (United States); Spinrad, Hyron [University of California, Berkeley, CA (United States); Reddy, Naveen [University of California, Riverside, CA (United States); Hathi, Nimish [Observatories of the Carnegie Institution of Washington, Pasadena, CA (United States); Budavari, Tamas [Johns Hopkins University, Baltimore, MD (United States); Ferreras, Ignacio [Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT (United Kingdom); Gardner, Jonathan P. [NASA Goddard Space Flight Center, Astrophysics Science Division, Observational Cosmology Laboratory, Code 665, Greenbelt, MD 20771 (United States); Gronwall, Caryl [Department of Astronomy and Astrophysics, and Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, PA 16802 (United States); Haiman, Zoltan [Columbia University, New York, NY (United States); Kuemmel, Martin [Universitaets-Sternwarte Muenchen, Scheinerstr. 1, D-81679 Muenchen (Germany); Meurer, Gerhardt, E-mail: James.Rhoads@asu.edu [International Centre for Radio Astronomy Research, University of Western Australia, M468, 35 Stirling Highway, Crawley, WA 6009 (Australia); and others

    2013-08-10

    We present observations of a luminous galaxy at z = 6.573-the end of the reionization epoch-which has been spectroscopically confirmed twice. The first spectroscopic confirmation comes from slitless Hubble Space Telescope Advanced Camera for Surveys grism spectra from the PEARS survey (Probing Evolution And Reionization Spectroscopically), which show a dramatic continuum break in the spectrum at rest frame 1216 A. The second confirmation is done with Keck + DEIMOS. The continuum is not clearly detected with ground-based spectra, but high wavelength resolution enables the Ly{alpha} emission line profile to be determined. We compare the line profile to composite line profiles at z = 4.5. The Ly{alpha} line profile shows no signature of a damping wing attenuation, confirming that the intergalactic gas is ionized at z = 6.57. Spectra of Lyman breaks at yet higher redshifts will be possible using comparably deep observations with IR-sensitive grisms, even at redshifts where Ly{alpha} is too attenuated by the neutral intergalactic medium to be detectable using traditional spectroscopy from the ground.

  14. Hubble Space Telescope observations of comet P/Shoemaker-Levy 9 (1993e)

    Science.gov (United States)

    Weaver, H.A.; Feldman, P.D.; A'Hearn, M.F.; Arpigny, C.; Brown, R.A.; Helin, E.F.; Levy, D.H.; Marsden, B.G.; Meech, K.J.; Larson, S.M.; Noll, K.S.; Scotti, J.V.; Sekanina, Z.; Shoemaker, C.S.; Shoemaker, E.M.; Smith, T.E.; Storrs, A.D.; Yeomans, D.K.; Zellner, B.

    1994-01-01

    The Hubble Space Telescope observed the fragmented comet P/Shoemaker-Levy 9 (1993e) (P indicates that it is a periodic comet) on 1 July 1993. Approximately 20 individual nuclei and their comae were observed in images taken with the Planetary Camera. After subtraction of the comae light, the 11 brightest nuclei have magnitudes between ~23.7 and 24.8. Assuming that the geometric albedo is 0.04, these magnitudes imply that the nuclear diameters are in the range ~2.5 to 4.3 kilometers. If the density of each nucleus is 1 gram per cubic centimeter, the total energy deposited by the impact of these 11 nuclei into Jupiter's atmosphere next July will be ~4 x 1030 ergs (~108 megatons of TNT). This latter number should be regarded as an upper limit because the nuclear magnitudes probably contain a small residual coma contribution. The Faint Object Spectrograph was used to search for fluorescence from OH, which is usually an excellent indicator of cometary activity. No OH emission was detected, and this can be translated into an upper limit on the water production rate of ~2 x 1027 molecules per second.

  15. The FUV detector for the cosmic origins spectrograph on the Hubble Space Telescope

    CERN Document Server

    Vallerga, J; Welsh, B; Siegmund, O; McPhate, J; Hull, J; Gaines, G; Buzasi, D L

    2002-01-01

    The Cosmic Origins Spectrograph (COS) is a high throughput spectrometer that will be placed on the Hubble Space Telescope (HST) during the last servicing mission in the year 2003. COS will be the most sensitive UV spectrograph ever flown aboard HST and will investigate such fundamental issues as the ionization and baryon content of the intergalactic medium and the origin of large-scale structure of the Universe. The driving design goal for COS is to maximize throughput at a moderate spectral resolution of >20,000 using optics with very few reflections and detectors with high quantum efficiency in two bandpass channels: FUV (1150-1775 A) and NUV (1750-3200 A). The COS FUV detector, a windowless microchannel plate (MCP) detector, consists of two segments each 85 mmx10 mm concatenated end to end with a 9 mm gap between them. The design is based on the Far Ultraviolet Spectroscopic Explorer detectors with identical format and front surface radius of curvature that matches the grating focal plane of the spectrogra...

  16. The Star Formation History of Leo T from Hubble Space Telescope Imaging

    CERN Document Server

    Weisz, Daniel R; Dolphin, Andrew E; Martin, Nicolas F; de Jong, Jelte T A; Holtzman, Jon A; Dalcanton, Julianne J; Gilbert, Karoline M; Williams, Benjamin F; Bell, Eric F; Belokurov, Vasily; Evans, N Wyn

    2012-01-01

    We present the star formation history (SFH) of the faintest known star-forming galaxy, Leo T, based on imaging taken with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2). The HST/WFPC2 color-magnitude diagram (CMD) of Leo T is exquisitely deep, extending ~ 2 magnitudes below the oldest main sequence turnoff, permitting excellent constraints on star formation at all ages. We use a maximum likelihood CMD fitting technique to measure the SFH of Leo T assuming three different sets of stellar evolution models: Padova (solar-scaled metallicity) and BaSTI (both solar-scaled and alpha-enhanced metallicities). The resulting SFHs are remarkably consistent at all ages, indicating that our derived SFH is robust to the choice of stellar evolution model. From the lifetime SFH of Leo T, we find that 50% of the total stellar mass formed prior to z ~ 1 (7.6 Gyr ago). Subsequent to this epoch, the SFH of Leo T is roughly constant until the most recent ~ 25 Myr, where the SFH shows an abrupt drop. This de...

  17. A Hubble Space Telescope Study of the Enigmatic Milky Way Halo Globular Cluster Crater

    CERN Document Server

    Weisz, Daniel R; Dolphin, Andrew E; Belokurov, Vasily; Gieles, Mark; Mateo, Mario L; Olszewski, Edward W; Sills, Alison; Walker, Matthew G

    2015-01-01

    We analyze the resolved stellar populations of the faint stellar system, Crater, based on deep optical imaging taken with the Hubble Space Telescope. The HST/ACS-based color-magnitude diagram (CMD) of Crater extends $\\sim$4 magnitudes below the oldest main sequence turnoff, providing excellent leverage on Crater's physical properties. Structurally, Crater has a half-light radius of $\\sim$20 pc and shows no evidence for tidal distortions. Crater is well-described by a simple stellar population with an age of $\\sim$7.5 Gyr, [M/H]$\\sim-1.65$, a M$_{\\star}\\sim10^4$ M$_{\\odot}$, M$_{\\rm V}\\sim -5.3$, located at a distance of (d$_{\\odot}$, d$_{\\rm GC}$) $\\sim$ (145, 110) kpc, with modest uncertainties in these properties due to differences in the underlying stellar evolution models. The sparse sampling of stars above the turnoff and sub-giant branch are likely to be 1.0-1.4 M$_{\\odot}$ binary star systems (blue stragglers) and their evolved descendants, as opposed to intermediate age main sequence stars. Confusion ...

  18. Infall of nearby galaxies into the Virgo cluster as traced with Hubble space telescope

    Energy Technology Data Exchange (ETDEWEB)

    Karachentsev, Igor D. [Special Astrophysical Observatory RAS, Nizhnij Arkhyz, Karachai-Cherkessian Republic 369167 (Russian Federation); Tully, R. Brent; Wu, Po-Feng [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Shaya, Edward J. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Dolphin, Andrew E., E-mail: ikar@sao.ru [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States)

    2014-02-10

    We measured the tip of the red giant branch distances to nine galaxies in the direction to the Virgo cluster using the Advanced Camera for Surveys on the Hubble Space Telescope. These distances put seven galaxies (GR 34, UGC 7512, NGC 4517, IC 3583, NGC 4600, VCC 2037, and KDG 215) in front of Virgo and two galaxies (IC 3023 and KDG 177) likely inside the cluster. Distances and radial velocities of the galaxies situated between us and the Virgo core clearly exhibit the infall phenomenon toward the cluster. In the case of spherically symmetric radial infall, we estimate the radius of the 'zero-velocity surface' to be (7.2 ± 0.7) Mpc, which yields a total mass of the Virgo cluster of (8.0 ± 2.3) × 10{sup 14} M {sub ☉}, in good agreement with its virial mass estimates. We conclude that the Virgo outskirts do not contain significant amounts of dark matter beyond their virial radius.

  19. Hubble Space Telescope Imaging of the Expanding Nebular Remnant of the Recurrent Nova RS Ophiuchi (2006)

    CERN Document Server

    Bode, M F; O'Brien, T J; Bond, H E; Starrfield, S; Darnley, M J; Evans, A; Eyres, S P S

    2007-01-01

    We report Hubble Space Telescope imaging obtained 155 days after the 2006 outburst of RS Ophiuchi. We detect extended emission in both [O III] and [Ne V] lines. In both lines, the remnant has a double ring structure. The E-W orientation and total extent of these structures (580+-50 AU at d=1.6kpc) is consistent with that expected due to expansion of emitting regions imaged earlier in the outburst at radio wavelengths. Expansion at high velocity appears to have been roughly constant in the E-W direction (v_{exp} = 3200+-300 km/s in the plane of the sky), with tentative evidence of deceleration N-S. We present a bipolar model of the remnant whose inclination is consistent with that of the central binary. The true expansion velocities of the polar components are then v = 5600+-1100 km/s. We suggest that the bipolar morphology of the remnant results from interaction of the outburst ejecta with a circumstellar medium that is significantly denser in the equatorial regions of the binary than at the poles. This is al...

  20. Multiwavelength Photometry and Hubble Space Telescope Spectroscopy of the Old Nova V842 Centaurus

    CERN Document Server

    Sion, Edward M; Mukadam, Anjum; Warner, Brian; Woudt, Patrick; Walter, Frederic; Henden, Arne; Godon, Patrick

    2013-01-01

    We present ground-based optical and near infrared photometric observations and Hubble Space Telescope COS spectroscopic observations of the old nova V842 Cen (Nova Cen 1986). Analysis of the optical light curves reveals a peak at 56.5 +/- 0.3s with an amplitude of 8.9 +/- 4.2 mma, which is consistent with the rotation of a magnetic white dwarf primary in V842 Cen that was detected earlier by Woudt et al., and led to its classification as an intermediate polar.However, our UV lightcurve created from the COS time-tag spectra does not show this periodicity. Our synthetic spectral analysis of an HST COS spectrum rules out a hot white dwarf photosphere as the source of the FUV flux. The best-fitting model to the COS spectrum is a full optically thick accretion disk with no magnetic truncation, a low disk inclination angle, low accretion rate and a distance less than half the published distance that was determined on the basis of interstellar sodium D line strengths.Truncated accretion disks with truncation radii o...

  1. Hubble Space Telescope Observations of M32 The Color-Magnitude Diagram

    CERN Document Server

    Grillmair, C J; Worthey, G; Faber, S M; Freedman, W L; Madore, B F; Ajhar, E A; Baum, W A; Holtzmann, J A; Lynds, C R; O'Neil, E J; Stetson, P B; Grillmair, Carl J.; Lauer, Tod R.; Worthey, Guy; Freedman, Wendy L.; Madore, Barry F.; Ajhar, Edward A.; Baum, William A.; Holtzman, Jon A.; Neil, Earl J. O'; Stetson, Peter B.

    1996-01-01

    We present a V-I color-magnitude diagram for a region 1'-2' from the center of M32 based on Hubble Space Telescope WFPC2 images. The broad color-luminosity distribution of red giants shows that the stellar population comprises stars with a wide range in metallicity. This distribution cannot be explained by a spread in age. The blue side of the giant branch rises to M_I ~ -4.0 and can be fitted with isochrones having [Fe/H] ~ -1.5. The red side consists of a heavily populated and dominant sequence that tops out at M_I ~ -3.2, and extends beyond V-I=4. This sequence can be fitted with isochrones with -0.2 < [Fe/H] < +0.1, for ages running from 15 Gyr to 5 Gyr respectively. We do not find the optically bright asymptotic giant branch stars seen in previous ground-based work and argue that the majority of them were artifacts of crowding. Our results are consistent with the presence of the infrared-luminous giants found in ground-based studies, though their existence cannot be directly confirmed by our data. ...

  2. Second Epoch Hubble Space Telescope Observations of Kepler's Supernova Remnant: The Proper Motions of Balmer Filaments

    CERN Document Server

    Sankrit, Ravi; Blair, William P; Long, Knox S; Williams, Brian J; Borkowski, Kazimierz J; Patnaude, Daniel J; Reynolds, Stephen P

    2015-01-01

    We report on the proper motions of Balmer-dominated filaments in Kepler's supernova remnant using high resolution images obtained with the Hubble Space Telescope at two epochs separated by about 10 years. We use the improved proper motion measurements and revised values of shock velocities to derive a distance to Kepler of 5.1 [+0.8, -0.7] kpc. The main shock around the northern rim of the remnant has a typical speed of 1690 km/s and is encountering material with densities of about 8 cm^-3. We find evidence for the variation of shock properties over small spatial scales, including differences in the driving pressures as the shock wraps around a curved cloud surface. We find that the Balmer filaments ahead of the ejecta knot on the northwest boundary of the remnant are becoming fainter and more diffuse. We also find that the Balmer filaments associated with circumstellar material in the interior regions of the remnant are due to shocks with significantly lower velocities and that the brightness variations amon...

  3. Discovery of an Unusual Optical Transient with the Hubble Space Telescope

    Energy Technology Data Exchange (ETDEWEB)

    The Supernova Cosmology Project; Barbary, Kyle; Dawson, Kyle S.; Tokita, Kouichi; Aldering, Greg; Amanullah, Rahman; Connolly, Natalia V.; Doi, Mamoru; Faccioli, Lorenzo; Fadeyev, Vitaliy; Fruchter, Andrew S.; Goldhaber, Gerson; Goobar, Ariel; Gude, Alexander; Huang, Xiaosheng; Ihara, Yutaka; Konishi, Kohki; Kowalski, Marek; Lidman, Chris; Meyers, Josh; Morokuma, Tomoki; Nugent, Peter; Perlmutter, Saul; Rubin, David; Schlegel, David; Spadafora, Anthony L.; Suzuki, Nao; Swift, Hannah K.; Takanashi, Naohiro; Thomas, Rollin C.; Yasuda, Naoki

    2008-09-08

    We present observations of SCP 06F6, an unusual optical transient discovered during the Hubble Space Telescope Cluster Supernova Survey. The transient brightened over a period of ~;;100 days, reached a peak magnitude of ~;;21.0 in both i_775 and z_850, and then declined over a similar timescale. There is no host galaxy or progenitor star detected at the location of the transient to a 3 sigma upper limit of i_775 = 26.4 and z_850 = 26.1, giving a corresponding lower limit on the flux increase of a factor of ~;;120. Multiple spectra show five broad absorption bands between 4100 AA and 6500 AA and a mostly featureless continuum longward of 6500 AA. The shape of the lightcurve is inconsistent with microlensing. The transient's spectrum, in addition to being inconsistent with all known supernova types, is not matched to any spectrum in the Sloan Digital Sky Survey (SDSS) database. We suggest that the transient may be one of a new class.

  4. Hubble Space Telescope observations of cool white dwarf stars: Detection of new species of heavy elements

    Science.gov (United States)

    Shipman, Harry; Barnhill, Maurice; Provencal, Judi; Roby, Scott; Bues, Irmela; Cordova, France; Hammond, Gordon; Hintzen, Paul; Koester, Detlev; Liebert, James

    1995-01-01

    Observations of cool white dwarf stars with the Hubble Space Telescope (HST) has uncovered a number of spectral features from previouslly unobserved species. In this paper we present the data on four cool white dwarfs. We present identifications, equivalent width measurements, and brief summaries of the significance of our findings. The four stars observed are GD 40 (DBZ3, G 74-7 (DAZ), L 745-46A (DZ), and LDS 749B (DBA). Many additional species of heavey elements were detected in GD 40 and G 74-7. In L 745-46A, while the detections are limited to Fe 1, Fe II, and Mg II, the quality of the Mg II h and K line profiles should permit a test of the line broadening theories, which are so crucial to abundance determinations. The clear detection of Mg II h and k in LDS 749 B should, once an abundance determination is made, provide a clear test of the hypothesis that the DBA stars are the result of accretion from the interstellar medium. This star contains no other clear features other than a tantalizing hint of C II 1335 with a P Cygni profile, and some expected He 1 lines.

  5. Hubble Space Telescope Fine Guidance Sensor Parallaxes of Galactic Cepheid Variable Stars: Period-Luminosity Relations

    CERN Document Server

    Benedict, G F; Feast, M W; Barnes, T G; Harrison, T E; Patterson, R J; Menzies, J W; Bean, J L; Freedman, W L; Arthur, Barbara E. Mc; Feast, Michael W.; Barnes, Thomas G.; Harrison, Thomas E.; Patterson, Richard J.; Menzies, John W.; Bean, Jacob L.; Freedman, Wendy L.

    2006-01-01

    (abridged) We present new absolute trigonometric parallaxes and relative proper motions for nine Galactic Cepheid variable stars: l Car, zeta Gem, beta Dor, W Sgr, X Sgr, Y Sgr, FF Aql, T Vul, and RT Aur. We obtain these results with astrometric data from Fine Guidance Sensor 1r, a white-light interferometer on Hubble Space Telescope. We find absolute parallaxes with an average sigma_pi/pi = 8%. Two stars (FF Aql and W Sgr) required the inclusion of binary astrometric perturbations, providing Cepheid mass estimates. With these parallaxes we compute absolute magnitudes in V, I, K, and Wesenheit W_{VI} bandpasses corrected for interstellar extinction and Lutz-Kelker-Hanson bias. Adding our previous absolute magnitude determination for delta Cep, we construct Period-Luminosity relations for ten Galactic Cepheids. We compare our new Period-Luminosity relations with those adopted by several recent investigations, including the Freedman and Sandage H_0 projects. Adopting our Period-Luminosity relationship would ten...

  6. Hubble Space Telescope Imaging of Lyman Alpha Emission at z=4.4

    CERN Document Server

    Finkelstein, Steven L; Windhorst, Rogier A; Ryan, Russell E; Hathi, Nimish P; Finkelstein, Keely D; Anderson, Jay; Grogin, Norman A; Koekemoer, Anton M; Malhotra, Sangeeta; Mutchler, Max; Rhoads, James E; McCarthy, Patrick J; O'Connell, Robert W; Balick, Bruce; Bond, Howard E; Calzetti, Daniela; Disney, Michael J; Dopita, Michael A; Frogel, Jay A; Hall, Donald N B; Holtzman, Jon A; Kimble, Randy A; Luppino, Gerard; Paresce, Francesco; Saha, Abhijit; Silk, Joseph I; Trauger, John T; Walker, Alistair R; Whitmore, Bradley C; Young, Erick T

    2010-01-01

    We present the highest redshift detections of resolved Lyman alpha emission, using Hubble Space Telescope/ACS F658N narrowband-imaging data taken in parallel with the Wide Field Camera 3 Early Release Science program in the GOODS CDF-S. We detect Lyman alpha emission from three spectroscopically confirmed z = 4.4 Lyman alpha emitting galaxies (LAEs), more than doubling the sample of LAEs with resolved Lyman alpha emission. Comparing the light distribution between the rest-frame ultraviolet continuum and narrowband images, we investigate the escape of Lyman alpha photons at high redshift. While our data do not support a positional offset between the Lyman alpha and rest-frame ultraviolet (UV) continuum emission, the half-light radii in two out of the three galaxies are significantly larger in Lyman alpha than in the rest-frame UV continuum. This result is confirmed when comparing object sizes in a stack of all objects in both bands. Additionally, the narrowband flux detected with HST is significantly less than...

  7. Confirmation of Hostless Type Ia Supernovae Using Hubble Space Telescope Imaging

    CERN Document Server

    Graham, Melissa L; Zaritsky, Dennis; Pritchet, Chris J

    2015-01-01

    We present deep Hubble Space Telescope imaging at the locations of four, potentially hostless, long-faded Type Ia supernovae (SNe Ia) in low-redshift, rich galaxy clusters that were identified in the Multi-Epoch Nearby Cluster Survey. Assuming a steep faint-end slope for the galaxy cluster luminosity function ($\\alpha_d=-1.5$), our data includes all but $\\lesssim0.2\\%$ percent of the stellar mass in cluster galaxies ($\\lesssim0.005\\%$ with $\\alpha_d=-1.0$), a factor of 10 better than our ground-based imaging. Two of the four SNe Ia still have no possible host galaxy associated with them ($M_R>-9.2$), confirming that their progenitors belong to the intracluster stellar population. The third SNe Ia appears near a faint disk galaxy ($M_V=-12.2$) which has a relatively high probability of being a chance alignment. A faint, red, point source coincident with the fourth SN Ia's explosion position ($M_V=-8.4$) may be either a globular cluster (GC) or faint dwarf galaxy. We estimate the local surface densities of GCs ...

  8. Discovery of an Unusual Optical Transient with the Hubble Space Telescope

    Energy Technology Data Exchange (ETDEWEB)

    The Supernova Cosmology Project; Barbary, Kyle; Dawson, Kyle S.; Tokita, Kouichi; Aldering, Greg; Amanullah, Rahman; Connolly, Natalia V.; Doi, Mamoru; Faccioli, Lorenzo; Fadeyev, Vitaliy; Fruchter, Andrew S.; Goldhaber, Gerson; Goobar, Ariel; Gude, Alexander; Huang, Xiaosheng; Ihara, Yutaka; Konishi, Kohki; Kowalski, Marek; Lidman, Chris; Meyers, Josh; Morokuma, Tomoki; Nugent, Peter; Perlmutter, Saul; Rubin, David; Schlegel, David; Spadafora, Anthony L.; Suzuki, Nao; Swift, Hannah K.; Takanashi, Naohiro; Thomas, Rollin C.; Yasuda, Naoki

    2008-09-08

    We present observations of SCP 06F6, an unusual optical transient discovered during the Hubble Space Telescope Cluster Supernova Survey. The transient brightened over a period of ~;;100 days, reached a peak magnitude of ~;;21.0 in both i_775 and z_850, and then declined over a similar timescale. There is no host galaxy or progenitor star detected at the location of the transient to a 3 sigma upper limit of i_775 = 26.4 and z_850 = 26.1, giving a corresponding lower limit on the flux increase of a factor of ~;;120. Multiple spectra show five broad absorption bands between 4100 AA and 6500 AA and a mostly featureless continuum longward of 6500 AA. The shape of the lightcurve is inconsistent with microlensing. The transient's spectrum, in addition to being inconsistent with all known supernova types, is not matched to any spectrum in the Sloan Digital Sky Survey (SDSS) database. We suggest that the transient may be one of a new class.

  9. Ultraviolet to optical diffuse sky emission as seen by the Hubble Space Telescope Faint Object Spectrograph

    Science.gov (United States)

    Kawara, Kimiaki; Matsuoka, Yoshiki; Sano, Kei; Brandt, Timothy D.; Sameshima, Hiroaki; Tsumura, Kohji; Oyabu, Shinki; Ienaka, Nobuyuki

    2017-02-01

    We present an analysis of the blank-sky spectra observed with the Faint Object Spectrograph on board the Hubble Space Telescope. We study the diffuse sky emission from ultraviolet to optical wavelengths, which is composed of zodiacal light (ZL), diffuse Galactic light (DGL), and residual emission. The observations were performed towards 54 fields distributed widely over the sky, with spectral coverage from 0.2 to 0.7 μm. In order to avoid contaminating light from earthshine, we use the data collected only in orbital nighttime. The observed intensity is decomposed into the ZL, DGL, and residual emission, in eight photometric bands spanning our spectral coverage. We found that the derived ZL reflectance spectrum is flat in the optical, which indicates major contribution of C-type asteroids to the interplanetary dust (IPD). In addition, the ZL reflectance spectrum has an absorption feature at ∼0.3 μm. The shape of the DGL spectrum is consistent with those found in earlier measurements and model predictions. While the residual emission contains a contribution from the extragalactic background light, we found that the spectral shape of the residual looks similar to the ZL spectrum. Moreover, its optical intensity is much higher than that measured from beyond the IPD cloud by Pioneer 10/11, and also than that of the integrated galaxy light. These findings may indicate the presence of an isotropic ZL component, which is missed in the conventional ZL models.

  10. Hubble Space Telescope observations of the host galaxies and environments of calcium-rich supernovae

    CERN Document Server

    Lyman, J D; James, P A; Angus, C R; Church, R P; Davies, M B; Tanvir, N R

    2016-01-01

    Calcium-rich supernovae represent a significant challenge for our understanding of the fates of stellar systems. They are less luminous than other supernova (SN) types and they evolve more rapidly to reveal nebular spectra dominated by strong calcium lines with weak or absent signatures of other intermediate- and iron-group elements, which are seen in other SNe. Strikingly, their explosion sites also mark them out as distinct from other SN types. Their galactocentric offset distribution is strongly skewed to very large offsets (around one third are offset greater than 20 kpc), meaning they do not trace the stellar light of their hosts. Many of the suggestions to explain this extreme offset distribution have invoked the necessity for unusual formation sites such as globular clusters or dwarf satellite galaxies, which are therefore difficult to detect. Building on previous work attempting to detect host systems of nearby Ca-rich SNe, we here present Hubble Space Telescope imaging of 5 members of the class - 3 e...

  11. Hubble space telescope high-resolution imaging of Kepler small and cool exoplanet host stars

    Energy Technology Data Exchange (ETDEWEB)

    Gilliland, Ronald L.; Cartier, Kimberly M. S.; Wright, Jason T. [Department of Astronomy and Astrophysics, and Center for Exoplanets and Habitable Worlds, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Adams, Elisabeth R. [Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719 (United States); Ciardi, David R. [NASA Exoplanet Science Institute/Caltech, Pasadena, CA 91125 (United States); Kalas, Paul, E-mail: gillil@stsci.edu [Astronomy Department, University of California, Berkeley, CA 94720 (United States)

    2015-01-01

    High-resolution imaging is an important tool for follow-up study of exoplanet candidates found via transit detection with the Kepler mission. We discuss here Hubble Space Telescope imaging with the WFC3 of 23 stars that host particularly interesting Kepler planet candidates based on their small size and cool equilibrium temperature estimates. Results include detections, exclusion of background stars that could be a source of false positives for the transits, and detection of physically associated companions in a number of cases providing dilution measures necessary for planet parameter refinement. For six Kepler objects of interest, we find that there is ambiguity regarding which star hosts the transiting planet(s), with potentially strong implications for planetary characteristics. Our sample is evenly distributed in G, K, and M spectral types. Albeit with a small sample size, we find that physically associated binaries are more common than expected at each spectral type, reaching a factor of 10 frequency excess in M. We document the program detection sensitivities, detections, and deliverables to the Kepler follow-up program archive.

  12. Analyzing the Low State of EF Eridani with Hubble Space Telescope Ultraviolet Spectra

    CERN Document Server

    Szkody, Paula; Gaensicke, Boris T; Campbell, Ryan K; Harrison, Thomas E; Howell, Steve B; Holtzman, Jon; Walter, Frederick M; Henden, Arne; Dillon, William; Boberg, Owen; Dealaman, Shannon; Perone, Christian S

    2010-01-01

    Time-resolved spectra throughout the orbit of EF Eri during its low accretion state were obtained with the Solar Blind Channel on the Advanced Camera for Surveys onboard the Hubble Space Telescope. The overall spectral distribution exhibits peaks at 1500 and 1700A, while the UV light curves display a quasi-sinusoidal modulation over the binary orbit. Models of white dwarfs with a hot spot and cyclotron emission were attempted to fit the spectral variations throughout the orbit. A non-magnetic white dwarf with a temperature of ~10,000K and a hot spot with central temperature of 15,000K generally matches the broad absorptions at 1400 and 1600A with those expected for the quasimolecular H features H2 and H+2 . However, the flux in the core of the Lyalpha absorption does not go to zero, implying an additional component, and the flux variations throughout the orbit are not well matched at long wavelengths. Alternatively, a 9500K white dwarf with a 100 MG cyclotron component can fit the lowest (phase 0.0) fluxes, b...

  13. V838 Monocerotis: A Geometric Distance from Hubble Space Telescope Polarimetric Imaging of its Light Echo

    CERN Document Server

    Sparks, William B; Cracraft, Misty; Levay, Zolt; Crause, Lisa A; Dopita, Michael A; Henden, Arne A; Munari, Ulisse; Panagia, Nino; Starrfield, Sumner G; Sugerman, Ben E; Wagner, R Mark; White, Richard L

    2007-01-01

    Following the outburst of the unusual variable star V838 Monocerotis in 2002, a spectacular light echo appeared. A light echo provides the possibility of direct geometric distance determination, because it should contain a ring of highly linearly polarized light at a linear radius of ct, where t is the time since the outburst. We present imaging polarimetry of the V838 Mon light echo, obtained in 2002 and 2005 with the Advanced Camera for Surveys onboard the Hubble Space Telescope, which confirms the presence of the highly polarized ring. Based on detailed modeling that takes into account the outburst light curve, the paraboloidal echo geometry, and the physics of dust scattering and polarization, we find a distance of 6.1+-0.6 kpc. The error is dominated by the systematic uncertainty in the scattering angle of maximum linear polarization, taken to be theta_{max}=90^o +- 5^o. The polarimetric distance agrees remarkably well with a distance of 6.2+-1.5 kpc obtained from the entirely independent method of main-...

  14. Hubble space telescope observations of white dwarfs in the globular cluster M4

    CERN Document Server

    Richer, H B; Ibata, R A; Stetson, P B; Bell, R A; Bolte, M; Bond, H E; Harris, W E; Hesser, J E; Mandushev, G I; Pryor, C E; Richer, Harvey B; Fahlman, Gregory G; Ibata, Rodrigo A; Stetson, Peter B; Bell, Roger A; Bolte, Michael; Bond, Howard E; Harris, William E; Hesser, James E; Mandushev, Georgi; Pryor, Carlton

    1995-01-01

    With the Wide Field Planetary Camera 2 (WFPC2) on the Hubble Space Telescope, we have discovered in M4 (NGC 6121, C 1620-264) the first extensive sequence of cooling white dwarfs seen in a globular cluster. Adopting a distance modulus of (m-M)_V = 12.65 and a reddening of E(B-V) = 0.37, we show that the sequence, which extends over 9 < M_U < 13, is comprised of white dwarfs of mass \\sim 0.5 M_{\\odot}. The total mass loss from the present turnoff to the white dwarf sequence is 0.31 M_{\\odot} and the intrinsic dispersion in the mean mass appears to be < 0.05 M_{\\odot}. Both the location of the white dwarf cooling sequence in the cluster color-magnitude diagram and the cumulative luminosity function attest to the basic correctness and completeness of the physics in theoretical models for the upper three magnitudes of the observed white dwarf cooling sequence. To test the theory in globular clusters at cooling ages beyond \\sim 3 \\times 10^8 years will require deeper and more complete data.

  15. Legacy ExtraGalactic UV Survey (LEGUS) with The Hubble Space Telescope. I. Survey Description

    CERN Document Server

    Calzetti, D; Sabbi, E; Adamo, A; Smith, L J; Andrews, J E; Ubeda, L; Bright, S N; Thilker, D; Aloisi, A; Brown, T M; Chandar, R; Christian, C; Cignoni, M; Clayton, G C; da Silva, R; de Mink, S E; Dobbs, C; Elmegreen, B G; Elmegreen, D M; Evans, A S; Fumagalli, M; Gallagher, J S; Gouliermis, D A; Grebel, E K; Herrero, A; Hunter, D A; Johnson, K E; Kennicutt, R C; Kim, H; Krumholz, M R; Lennon, D; Levay, K; Martin, C; Nair, P; Nota, A; Oestlin, G; Pellerin, A; Prieto, J; Regan, M W; Ryon, J E; Schaerer, D; Schiminovich, D; Tosi, M; Van Dyk, S D; Walterbos, R; Whitmore, B C; Wofford, A; .,

    2014-01-01

    The Legacy ExtraGalactic UV Survey (LEGUS) is a Cycle 21 Treasury program on the Hubble Space Telescope, aimed at the investigation of star formation and its relation with galactic environment in nearby galaxies, from the scales of individual stars to those of ~kpc-size clustered structures. Five-band imaging, from the near-ultraviolet to the I-band, with the Wide Field Camera 3, plus parallel optical imaging with the Advanced Camera for Surveys, is being collected for selected pointings of 50 galaxies within the local 12 Mpc. The filters used for the observations with the Wide Field Camera 3 are: F275W(2,704 A), F336W(3,355 A), F438W(4,325 A), F555W(5,308 A), and F814W(8,024 A); the parallel observations with the Advanced Camera for Surveys use the filters: F435W(4,328 A), F606W(5,921 A), and F814W(8,057 A). The multi-band images are yielding accurate recent (<~50 Myr) star formation histories from resolved massive stars and the extinction-corrected ages and masses of star clusters and associations. The e...

  16. Chandra and Hubble Space Telescope Study of the Globular Cluster NGC 288

    CERN Document Server

    Kong, A K H; Pooley, D; Lewin, W H G; Homer, L; Verbunt, F; Anderson, S F; Margon, B

    2006-01-01

    We report on the Chandra X-ray Observatory observations of the globular cluster NGC 288. We detect four X-ray sources within the core radius and seven additional sources within the half-mass radius down to a limiting luminosity of Lx=7e30 erg/s (assuming cluster membership) in the 0.3-7 keV band. We also observed the cluster with the Hubble Space Telescope Advanced Camera for Surveys and identify optical counterparts to seven X-ray sources out of the nine sources within the HST field-of-view. Based on the X-ray and optical properties, we find 2-5 candidates of cataclysmic variables (CVs) or chromospherically active binaries, and 2-5 background galaxies inside the half-mass radius. Since the core density of NGC 288 is very low, the faint X-ray sources of NGC 288 found in the Chandra and HST observations is higher than the prediction on the basis of the collision frequency. We suggest that the CVs and chromospherically active binaries are primordial in origin, in agreement with theoretical expectation.

  17. HUBBLE SPACE TELESCOPE EMISSION-LINE GALAXIES AT z ∼ 2: THE MYSTERY OF NEON

    Energy Technology Data Exchange (ETDEWEB)

    Zeimann, Gregory R.; Ciardullo, Robin; Gebhardt, Henry; Gronwall, Caryl; Hagen, Alex; Trump, Jonathan R.; Bridge, Joanna S.; Luo, Bin; Schneider, Donald P., E-mail: grzeimann@psu.edu [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)

    2015-01-01

    We use near-infrared grism spectroscopy from the Hubble Space Telescope to examine the strength of [Ne III] λ3869 relative to Hβ, [O II] λ3727, and [O III] λ5007 in 236 low-mass (7.5 ≲ log (M {sub *}/M {sub ☉}) ≲ 10.5) star-forming galaxies in the redshift range 1.90 < z < 2.35. By stacking the data by stellar mass, we show that the [Ne III]/[O II] ratios of the z ∼ 2 universe are marginally higher than those seen in a comparable set of local Sloan Digital Sky Survey galaxies, and that [Ne III]/[O III] is enhanced by ∼0.2 dex. We consider the possible explanations for this ∼4σ result, including higher oxygen depletion out of the gas phase, denser H II regions, higher production of {sup 22}Ne via Wolf-Rayet stars, and the existence of a larger population of X-ray obscured active galactic nuclei at z ∼ 2 compared to z ∼ 0. None of these simple scenarios, alone, are favored to explain the observed line ratios. We conclude by suggesting several avenues of future observations to further explore the mystery of enhanced [Ne III] emission.

  18. Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

    Science.gov (United States)

    Wang, Xiaofeng; Wang, Lifan; Filippenko, Alexei; Baron, Eddie; Kromer, Markus; Jack, Dennis; Zhang, Tianmeng; Aldering, Greg; Antilogus, Pierre; Arnett, W. David; hide

    2012-01-01

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope, This dataset provides unique spectral time series down to 2000 A. Significant diversity is seen in the near-maximum-light spectra (approx.2000-3500 A) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in the uvw lIF250W filter are found to correlate with the B-band light-curve shape parameter .(Delta)m15(B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., approx. 0.4 mag versus approx. 0.2 mag for those with 0.8 3(sigma), being brighter than normal SNe Ia such as SN 2005cf by approx. 0,9 mag and approx. 2.0 mag in the uvwl1F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effects

  19. A New Method for Wide-field Near-IR Imaging with the Hubble Space Telescope

    Science.gov (United States)

    Momcheva, Ivelina G.; van Dokkum, Pieter G.; van der Wel, Arjen; Brammer, Gabriel B.; MacKenty, John; Nelson, Erica J.; Leja, Joel; Muzzin, Adam; Franx, Marijn

    2017-01-01

    We present a new technique for wide and shallow observations using the near-infrared channel of Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). Wide-field near-IR surveys with HST are generally inefficient, as guide star acquisitions make it impractical to observe more than one pointing per orbit. This limitation can be circumvented by guiding with gyros alone, which is possible as long as the telescope has three functional gyros. The method presented here allows us to observe mosaics of eight independent WFC3-IR pointings in a single orbit by utilizing the fact that HST drifts by only a very small amount in the 25 s between non-destructive reads of unguided exposures. By shifting the reads and treating them as independent exposures the full resolution of WFC3 can be restored. We use this “drift and shift” (DASH) method in the Cycle 23 COSMOS-DASH program, which will obtain 456 WFC3 H 160 pointings in 57 orbits, covering an area of 0.6 degree in the COSMOS field down to H 160 = 25. When completed, the program will more than triple the area of extra-galactic survey fields covered by near-IR imaging at HST resolution. We demonstrate the viability of the method with the first four orbits (32 pointings) of this program. We show that the resolution of the WFC3 camera is preserved, and that structural parameters of galaxies are consistent with those measured in guided observations.

  20. EVIDENCE FOR TYPE Ia SUPERNOVA DIVERSITY FROM ULTRAVIOLET OBSERVATIONS WITH THE HUBBLE SPACE TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiaofeng [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084 (China); Wang Lifan [Physics and Astronomy Department, Texas A and M University, College Station, TX 77843 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Baron, Eddie [Department of Physics, University of Oklahoma, Norman, OK 73019 (United States); Kromer, Markus [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, 85748 Garching (Germany); Jack, Dennis [Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg (Germany); Zhang Tianmeng [National Astronomical Observatory of China, Chinese Academy of Sciences, Beijing 100012 (China); Aldering, Greg [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Antilogus, Pierre [Laboratoire de Physique Nucleaire des Hautes Energies, Paris (France); Arnett, W. David [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Baade, Dietrich [European Southern Observatory, 85748 Garching (Germany); Barris, Brian J. [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States); Benetti, Stefano; Cappellaro, Enrico [Osservatorio Astronomico di Padova, 35122 Padova (Italy); Bouchet, Patrice [CEA/DSM/DAPNIA/Service d' Astrophysique, 91191 Gif-sur-Yvette Cedex (France); Burrows, Adam S. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Canal, Ramon [Department d' Astronomia i Meterorologia, Universidad de Barcelona, Barcelona 8007 (Spain); Carlberg, Raymond G. [Department of Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S 3J3 (Canada); Di Carlo, Elisa [INAF, Osservatorio Astronomico di Teramo, 64100 Teramo (Italy); Challis, Peter J., E-mail: wang_xf@mail.tsinghua.edu.cn [Harvard/Smithsonian Center Astrophysics, Cambridge, MA 02138 (United States); and others

    2012-04-20

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This data set provides unique spectral time series down to 2000 A. Significant diversity is seen in the near-maximum-light spectra ({approx}2000-3500 A) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in the uvw1/F250W filter are found to correlate with the B-band light-curve shape parameter {Delta}m{sub 15}(B), but with much larger scatter relative to the correlation in the broadband B band (e.g., {approx}0.4 mag versus {approx}0.2 mag for those with 0.8 mag < {Delta}m{sub 15}(B) < 1.7 mag). SN 2004dt is found as an outlier of this correlation (at > 3{sigma}), being brighter than normal SNe Ia such as SN 2005cf by {approx}0.9 mag and {approx}2.0 mag in the uvw1/F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effects.

  1. The Deep Blue Color of HD189733b: Albedo Measurements with Hubble Space Telescope/Space Telescope Imaging Spectrograph at Visible Wavelengths

    CERN Document Server

    Evans, Thomas M; Sing, David K; Aigrain, Suzanne; Barstow, Joanna K; Désert, Jean-Michel; Gibson, Neale; Heng, Kevin; Knutson, Heather A; Etangs, Alain Lecavelier des

    2013-01-01

    We present a secondary eclipse observation for the hot Jupiter HD189733b across the wavelength range 290-570nm made using the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. We measure geometric albedos of Ag = 0.40 \\pm 0.12 across 290-450nm and Ag < 0.12 across 450-570nm at 1-sigma confidence. The albedo decrease toward longer wavelengths is also apparent when using six wavelength bins over the same wavelength range. This can be interpreted as evidence for optically thick reflective clouds on the dayside hemisphere with sodium absorption suppressing the scattered light signal beyond ~450nm. Our best-fit albedo values imply that HD189733b would appear a deep blue color at visible wavelengths.

  2. Hubble Space Telescope Fine Guidance Sensor Post-Flight Bearing Inspection

    Science.gov (United States)

    Pellicciotti, J.; Loewenthal, S.; Jones, W., Jr.; Jumper, M.

    2004-01-01

    Aerospace mechanism engineering success stories often, if not always, consist of overcoming developmental, test and flight anomalies. Many times it is these anomalies that stimulate technology growth and more reliable future systems. However, one must learn from these to achieve an ultimately successful mission. It is not often that a spacecraft engineer is able to inspect hardware that has flown in orbit for several years. However, in February 1997, the Fine Guidance Sensor-1 (FGS-1) was removed from the Hubble Space Telescope (HST) and returned to NASA Goddard Space Flight Center (GSFC) during the second Servicing Mission (SM2). At the time of removal, FGS-1 had nearly 7 years of service and the bearings in the Star Selector Servos (SSS) had accumulated approximately 25 million Coarse Track (CT) cycles. The main reason for its replacement was due to a bearing torque anomaly leading to stalling of the B Star Selector Servo (SSS-B) when reversing direction during a vehicle offset maneuver, referred to herein as a Reversal Bump (RB). The returned HST FGS SSS bearings were disassembled for post-service condition assessment to better understand the actual cause of the torque spikes, identify potential process/design improvements, and provide information for remedial on-orbit operation modifications. The methods and technology utilized for this inspection are not unique to this system and can be adapted to most investigations at varying stages of the mechanism life from development, through testing, to post flight evaluation. The systematic methods used for the HST Fine Guidance Sensor (FGS) SSS and specific findings are the subjects presented in this paper. The lessons learned include the importance of cleanliness and handling for precision instrument bearings and the potential effects from contamination. The paper describes in detail, the analytical techniques used for the SSS and their importance in this investigation. Inspection analytical data and photographs are

  3. Results of a technical analysis of the Hubble Space Telescope nickel-cadmium and nickel-hydrogen batteries

    Science.gov (United States)

    Manzo, Michelle A.

    1991-01-01

    The Hubble Space Telescope (HST) Program Office requested the expertise of the NASA Aerospace Flight Battery Systems Steering Committee (NAFBSSC) in the conduct of an independent assessment of the HST's battery system to assist in their decision of whether to fly nickel-cadmium or nickel-hydrogen batteries on the telescope. In response, a subcommittee to the NAFBSSC was organized with membership comprised of experts with background in the nickel-cadmium/nickel-hydrogen secondary battery/power systems areas. The work and recommendations of that subcommittee are presented.

  4. Mass and magnification maps for the Hubble Space Telescope Frontier Fields clusters: implications for high redshift studies

    CERN Document Server

    Richard, J; Limousin, M; Jullo, E; Clément, B; Ebeling, H; Kneib, J P; Atek, H; Natarajan, P; Egami, E; Livermore, R; Bower, R

    2014-01-01

    Extending over three Hubble Space Telescope (HST) cycles, the Hubble Frontier Fields (HFF) initiative constitutes the largest commitment ever of HST time to the exploration of the distant Universe via gravitational lensing by massive galaxy clusters. We here present models of the mass distribution in the six HFF cluster lenses, derived from a joint strong- and weak-lensing analysis anchored by a total of 618 multiple-image systems identified in existing HST data. The resulting maps of the projected mass distribution and of the gravitational magnification effectively calibrate the HFF clusters as gravitational telescopes. Allowing the computation of search areas in the source plane, these maps are provided to the community to facilitate the exploitation of forthcoming HFF data for quantitative studies of the gravitationally lensed population of background galaxies. Our models of the gravitational magnification afforded by the HFF clusters allow us to quantify the lensing-induced boost in sensitivity over blank...

  5. JET ROTATION INVESTIGATED IN THE NEAR-ULTRAVIOLET WITH THE HUBBLE SPACE TELESCOPE IMAGING SPECTROGRAPH

    Energy Technology Data Exchange (ETDEWEB)

    Coffey, Deirdre; Ray, Thomas P. [Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2, Republic of Ireland (Ireland); Rigliaco, Elisabetta; Bacciotti, Francesca [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze (Italy); Eisloeffel, Jochen, E-mail: dac@cp.dias.ie [Thueringer Landessternwarte Tautenburg, Sternwarte 5, 07778 Tautenburg (Germany)

    2012-04-20

    We present results of the second phase of our near-ultraviolet investigation into protostellar jet rotation using the Hubble Space Telescope Imaging Spectrograph. We obtain long-slit spectra at the base of five T Tauri jets to determine if there is a difference in radial velocity between the jet borders which may be interpreted as a rotation signature. These observations are extremely challenging and push the limits of current instrumentation, but have the potential to provide long-awaited observational support for the magnetocentrifugal mechanism of jet launching in which jets remove angular momentum from protostellar systems. We successfully detect all five jet targets (from RW Aur, HN Tau, DP Tau, and CW Tau) in several near-ultraviolet emission lines, including the strong Mg II doublet. However, only RW Aur's bipolar jet presents a sufficiently high signal-to-noise ratio to allow for analysis. The approaching jet lobe shows a difference of 10 km s{sup -1} in a direction which agrees with the disk rotation sense, but is opposite to previously published optical measurements for the receding jet. The near-ultraviolet difference is not found six months later, nor is it found in the fainter receding jet. Overall, in the case of RW Aur, differences are not consistent with a simple jet rotation interpretation. Indeed, given the renowned complexity and variability of this system, it now seems likely that any rotation signature is confused by other influences, with the inevitable conclusion that RW Aur is not suited to a jet rotation study.

  6. The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. VIII. Preliminary Public Catalog Release

    Science.gov (United States)

    Soto, M.; Bellini, A.; Anderson, J.; Piotto, G.; Bedin, L. R.; van der Marel, R. P.; Milone, A. P.; Brown, T. M.; Cool, A. M.; King, I. R.; Sarajedini, A.; Granata, V.; Cassisi, S.; Aparicio, A.; Hidalgo, S.; Ortolani, S.; Nardiello, D.

    2017-01-01

    The Hubble Space Telescope (HST) UV Legacy Survey of Galactic Globular Clusters (GO-13297) has been specifically designed to complement the existing F606W and F814W observations of the Advanced Camera for Surveys (ACS) Globular Cluster Survey (GO-10775) by observing the most accessible 47 of the previous survey’s 65 clusters in three WFC3/UVIS filters F275W, F336W, and F438W. The new survey also adds super-solar metallicity open cluster NGC 6791 to increase the metallicity diversity. The combined survey provides a homogeneous 5-band data set that can be used to pursue a broad range of scientific investigations. In particular, the chosen UV filters allow the identification of multiple stellar populations by targeting the regions of the spectrum that are sensitive to abundance variations in C, N, and O. In order to provide the community with uniform preliminary catalogs, we have devised an automated procedure that performs high-quality photometry on the new UV observations (along with similar observations of seven other programs in the archive). This procedure finds and measures the potential sources on each individual exposure using library point-spread functions and cross-correlates these observations with the original ACS-Survey catalog. The catalog of 57 clusters we publish here will be useful to identify stars in the different stellar populations, in particular for spectroscopic follow-up. Eventually, we will construct a more sophisticated catalog and artificial-star tests based on an optimal reduction of the UV survey data, but the catalogs presented here give the community the chance to make early use of this HST Treasury survey.

  7. THE STAR FORMATION HISTORY OF LEO T FROM HUBBLE SPACE TELESCOPE IMAGING

    Energy Technology Data Exchange (ETDEWEB)

    Weisz, Daniel R.; Dalcanton, Julianne J.; Gilbert, Karoline M.; Williams, Benjamin F. [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Zucker, Daniel B. [Department of Physics and Astronomy, Macquarie University, Sydney 2109 (Australia); Dolphin, Andrew E. [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Martin, Nicolas F. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); De Jong, Jelte T. A. [Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 Leiden (Netherlands); Holtzman, Jon A. [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger St., Las Cruces, NM 88003 (United States); Bell, Eric F. [Department of Astronomy, University of Michigan, 500 Church St., Ann Arbor, MI 48109 (United States); Belokurov, Vasily; Evans, N. Wyn, E-mail: dweisz@astro.washington.edu [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)

    2012-04-01

    We present the star formation history (SFH) of the faintest known star-forming galaxy, Leo T, based on deep imaging taken with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2). The HST/WFPC2 color-magnitude diagram (CMD) of Leo T is exquisitely deep, extending {approx}2 mag below the oldest main-sequence turnoff, permitting excellent constraints on star formation at all ages. We use a maximum likelihood CMD fitting technique to measure the SFH of Leo T assuming three different sets of stellar evolution models: Padova (solar-scaled metallicity) and BaSTI (both solar-scaled and {alpha}-enhanced metallicities). The resulting SFHs are remarkably consistent at all ages, indicating that our derived SFH is robust to the choice of stellar evolution model. From the lifetime SFH of Leo T, we find that 50% of the total stellar mass formed prior to z {approx} 1 (7.6 Gyr ago). Subsequent to this epoch, the SFH of Leo T is roughly constant until the most recent {approx}25 Myr, where the SFH shows an abrupt drop. This decrease could be due to a cessation of star formation or stellar initial mass function sampling effects, but we are unable to distinguish between the two scenarios. Overall, our measured SFH is consistent with previously derived SFHs of Leo T. However, the HST-based solution provides improved age resolution and reduced uncertainties at all epochs. The SFH, baryonic gas fraction, and location of Leo T are unlike any of the other recently discovered faint dwarf galaxies in the Local Group, and instead bear strong resemblance to gas-rich dwarf galaxies (irregular or transition), suggesting that gas-rich dwarf galaxies may share common modes of star formation over a large range of stellar mass ({approx}10{sup 5}-10{sup 9} M{sub Sun }).

  8. Hubble space telescope near-ir transmission spectroscopy of the super-Earth HD 97658B

    Energy Technology Data Exchange (ETDEWEB)

    Knutson, Heather A. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Dragomir, Diana [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Kreidberg, Laura; Bean, Jacob L. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Kempton, Eliza M.-R. [Department of Physics, Grinnell College, Grinnell, IA 50112 (United States); McCullough, P. R. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Gillon, Michael [Institut d' Astrophysique et de Géophysique, Universiteé de Liége, Liége 1 (Belgium); Homeier, Derek [Centre de Recherche Astrophysique de Lyon, F-69364 Lyon (France); Howard, Andrew W., E-mail: hknutson@caltech.edu [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States)

    2014-10-20

    Recent results from the Kepler mission indicate that super-Earths (planets with masses between 1-10 times that of the Earth) are the most common kind of planet around nearby Sun-like stars. These planets have no direct solar system analogue, and are currently one of the least well-understood classes of extrasolar planets. Many super-Earths have average densities that are consistent with a broad range of bulk compositions, including both water-dominated worlds and rocky planets covered by a thick hydrogen and helium atmosphere. Measurements of the transmission spectra of these planets offer the opportunity to resolve this degeneracy by directly constraining the scale heights and corresponding mean molecular weights of their atmospheres. We present Hubble Space Telescope near-infrared spectroscopy of two transits of the newly discovered transiting super-Earth HD 97658b. We use the Wide Field Camera 3's (WFC3) scanning mode to measure the wavelength-dependent transit depth in 30 individual bandpasses. Our averaged differential transmission spectrum has a median 1σ uncertainty of 23 ppm in individual bins, making this the most precise observation of an exoplanetary transmission spectrum obtained with WFC3 to date. Our data are inconsistent with a cloud-free solar metallicity atmosphere at the 10σ level. They are consistent at the 0.4σ level with a flat line model, as well as effectively flat models corresponding to a metal-rich atmosphere or a solar metallicity atmosphere with a cloud or haze layer located at pressures of 10 mbar or higher.

  9. The Lyman alpha reference sample. II. Hubble space telescope imaging results, integrated properties, and trends

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, Matthew; Östlin, Göran; Duval, Florent; Sandberg, Andreas; Guaita, Lucia; Melinder, Jens; Rivera-Thorsen, Thøger [Department of Astronomy, Oskar Klein Centre, Stockholm University, AlbaNova University Centre, SE-106 91 Stockholm (Sweden); Adamo, Angela [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Schaerer, Daniel [Université de Toulouse, UPS-OMP, IRAP, F-31000 Toulouse (France); Verhamme, Anne; Orlitová, Ivana [Geneva Observatory, University of Geneva, 51 Chemin des Maillettes, CH-1290 Versoix (Switzerland); Mas-Hesse, J. Miguel; Otí-Floranes, Héctor [Centro de Astrobiología (CSIC-INTA), Departamento de Astrofísica, P.O. Box 78, E-28691 Villanueva de la Cañada (Spain); Cannon, John M.; Pardy, Stephen [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Atek, Hakim [Laboratoire dAstrophysique, École Polytechnique Fédérale de Lausanne (EPFL), Observatoire, CH-1290 Sauverny (Switzerland); Kunth, Daniel [Institut d' Astrophysique de Paris, UMR 7095, CNRS and UPMC, 98 bis Bd Arago, F-75014 Paris (France); Laursen, Peter [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Herenz, E. Christian, E-mail: matthew@astro.su.se [Leibniz-Institut für Astrophysik (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany)

    2014-02-10

    We report new results regarding the Lyα output of galaxies, derived from the Lyman Alpha Reference Sample, and focused on Hubble Space Telescope imaging. For 14 galaxies we present intensity images in Lyα, Hα, and UV, and maps of Hα/Hβ, Lyα equivalent width (EW), and Lyα/Hα. We present Lyα and UV radial light profiles and show they are well-fitted by Sérsic profiles, but Lyα profiles show indices systematically lower than those of the UV (n ≈ 1-2 instead of ≳ 4). This reveals a general lack of the central concentration in Lyα that is ubiquitous in the UV. Photometric growth curves increase more slowly for Lyα than the far ultraviolet, showing that small apertures may underestimate the EW. For most galaxies, however, flux and EW curves flatten by radii ≈10 kpc, suggesting that if placed at high-z only a few of our galaxies would suffer from large flux losses. We compute global properties of the sample in large apertures, and show total Lyα luminosities to be independent of all other quantities. Normalized Lyα throughput, however, shows significant correlations: escape is found to be higher in galaxies of lower star formation rate, dust content, mass, and nebular quantities that suggest harder ionizing continuum and lower metallicity. Six galaxies would be selected as high-z Lyα emitters, based upon their luminosity and EW. We discuss the results in the context of high-z Lyα and UV samples. A few galaxies have EWs above 50 Å, and one shows f{sub esc}{sup Lyα} of 80%; such objects have not previously been reported at low-z.

  10. Hubble Space Telescope observations of Orion Nebula, Helix Nebula, and NGC 6822

    Science.gov (United States)

    Spitzer, Lyman; Fitzpatrick, Ed

    1999-01-01

    This grant covered the major part of the work of the Principal Investigator and his collaborators as a Guaranteed Time Observer on the Hubble Space Telescope. The work done naturally divided itself into two portions the first being study of nebular objects and the second investigation of the interstellar medium between stars. The latter investigation was pursued through a contract with Princeton University, with Professor Lyman Spitzer as the supervising astronomer, assisted by Dr. Ed Fitzpatrick. Following the abrupt death of Professor Spitzer, his responsibilities were shifted to Dr. Fitzpatrick. When Dr. Fitzpatrick relocated to Villanova University the concluding work on that portion of this grant was concluded under a direct service arrangement. This program has been highly successful and the resulting publications in scientific journals are listed below. To the scientist, this is the bottom line, so that I shall simply try to describe the general nature of what was accomplished. There were three nebular programs conducted, one on the Orion Nebula, the second on the Helix Nebula, and the third on NGC 6822. The largest program was that on the Orion Nebula. This involved both HST observations and supporting groundbased observations obtained with a variety of instruments, including the Coude Feed Telescope at the Kitt Peak National observatory in Arizona, the Cerro Tololo observatory in Chile, and the Keck Observatory on Mauna Kea, Hawaii. Moreover, considerable theoretical modeling was done and all of the data analysis was performed at the Rice University in Houston, except for the PI's period of sabbatical leave (6-96 through 7-97) when he was based at the Max Planck Institute for Astronomy in Heidelberg, Germany. The Orion Nebula program was the most productive part, resulting in numerous papers, but more important in the discovery of a new class of objects, for which we coined the name "proplyds". The proplyds are protoplanetary disks surrounding very young

  11. Hubble Space Telescope Wide Field Planetary Camera 2 Observations of Neptune

    Science.gov (United States)

    1995-01-01

    Two groups have recently used the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC 2) to acquire new high-resolution images of the planet Neptune. Members of the WFPC-2 Science Team, lead by John Trauger, acquired the first series of images on 27 through 29 June 1994. These were the highest resolution images of Neptune taken since the Voyager-2 flyby in August of 1989. A more comprehensive program is currently being conducted by Heidi Hammel and Wes Lockwood. These two sets of observations are providing a wealth of new information about the structure, composition, and meteorology of this distant planet's atmosphere.Neptune is currently the most distant planet from the sun, with an orbital radius of 4.5 billion kilometers (2.8 billion miles, or 30 Astronomical Units). Even though its diameter is about four times that of the Earth (49,420 vs. 12,742 km), ground-based telescopes reveal a tiny blue disk that subtends less than 1/1200 of a degree (2.3 arc-seconds). Neptune has therefore been a particularly challenging object to study from the ground because its disk is badly blurred by the Earth's atmosphere. In spite of this, ground-based astronomers had learned a great deal about this planet since its position was first predicted by John C. Adams and Urbain Leverrier in 1845. For example, they had determined that Neptune was composed primarily of hydrogen and helium gas, and that its blue color caused by the presence of trace amounts of the gas methane, which absorbs red light. They had also detected bright cloud features whose brightness changed with time, and tracked these clouds to infer a rotation period between 17 and 22 hours.When the Voyager-2 spacecraft flew past the Neptune in 1989, its instruments revealed a surprising array of meteorological phenomena, including strong winds, bright, high-altitude clouds, and two large dark spots attributed to long-lived giant storm systems. These bright clouds and dark spots were tracked as they moved

  12. A High Angular Resolution Survey of Massive Stars in Cygnus OB2: Results from the Hubble Space Telescope Fine Guidance Sensors

    Science.gov (United States)

    2014-02-01

    Printed in the U.S.A. A HIGH ANGULAR RESOLUTION SURVEY OF MASSIVE STARS IN CYGNUS OB2: RESULTS FROM THE HUBBLE SPACE TELESCOPE FINE GUIDANCE SENSORS...angular resolution survey of massive OB stars in the Cygnus OB2 association that we conducted with the fine guidance sensor 1R (FGS1r) on the Hubble Space...al. 2009) and imaging observations (Maı́z Apellániz 2010). The fine guidance sensors (FGSs) aboard the Hubble Space Telescope (HST) provide us with

  13. Proper motion of the Draco dwarf galaxy based on Hubble space telescope imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pryor, Carlton [Dept. of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Rd., Piscataway, NJ 08854-8019 (United States); Piatek, Slawomir [Dept. of Physics, New Jersey Institute of Technology, Newark, NJ 07102 (United States); Olszewski, Edward W., E-mail: pryor@physics.rutgers.edu, E-mail: piatek@physics.rutgers.edu, E-mail: eolszewski@as.arizona.edu [Steward Observatory, The University of Arizona, Tucson, AZ 85721 (United States)

    2015-02-01

    We have measured the proper motion of the Draco dwarf galaxy using images at two epochs with a time baseline of about two years taken with the Hubble Space Telescope Advanced Camera for Surveys. Wide Field Channels 1 and 2 provide two adjacent fields, each containing a known QSO. The zero point for the proper motion is determined using both background galaxies and the QSOs and the two methods produce consistent measurements within each field. Averaging the results from the two fields gives a proper motion in the equatorial coordinate system of (μ{sub α},μ{sub δ})=(17.7±6.3,−22.1±6.3) mas century{sup −1} and in the Galactic coordinate system of (μ{sub ℓ},μ{sub b})=(−23.1±6.3,−16.3±6.3) mas century{sup −1}. Removing the contributions of the motion of the Sun and of the LSR to the measured proper motion yields a Galactic rest-frame proper motion of (μ{sub α}{sup Grf},μ{sub δ}{sup Grf})=(51.4±6.3,−18.7±6.3) mas century{sup −1} and (μ{sub ℓ}{sup Grf},μ{sub b}{sup Grf})=(−21.8±6.3,−50.1±6.3) mas century{sup −1}. The implied space velocity with respect to the Galactic center is (Π,Θ,Z)=(27±14,89±25,−212±20) km s{sup −1}. This velocity implies that the orbital inclination is 70{sup ∘}, with a 95% confidence interval of (59{sup ∘},80{sup ∘}), and that the plane of the orbit is consistent with that of the vast polar structure (VPOS) of Galactic satellite galaxies.

  14. Innovative Resources for Education and Public Information: Electronic Services, Data and Information from NASA's Hubble Space Telescope and Other NASA Missions.

    Science.gov (United States)

    Christian, Carol A.

    The Space Telescope Science Institute (STScI), which supports the operation of the Hubble Space Telescope, is actively investigating and supporting innovative and experimental methods for improving science and math education content. The educational resources on the World Wide Web are derived from the latest data, scientific results, and advances…

  15. Optical Identification of Cepheids in 19 Host Galaxies of Type Ia Supernovae and NGC 4258 with the Hubble Space Telescope

    Science.gov (United States)

    Hoffmann, Samantha L.; Macri, Lucas M.; Riess, Adam G.; Yuan, Wenlong; Casertano, Stefano; Foley, Ryan J.; Filippenko, Alexei V.; Tucker, Brad E.; Chornock, Ryan; Silverman, Jeffrey M.; Welch, Douglas L.; Goobar, Ariel; Amanullah, Rahman

    2016-10-01

    We present results of an optical search conducted as part of the SH0ES project (Supernovae and H0 for the Equation of State of dark energy) for Cepheid variable stars using the Hubble Space Telescope (HST) in 19 hosts of Type Ia supernovae (SNe Ia) and the maser-host galaxy NGC 4258. The targets include nine newly imaged SN Ia hosts using a novel strategy based on a long-pass filter that minimizes the number of HST orbits required to detect and accurately determine Cepheid properties. We carried out a homogeneous reduction and analysis of all observations, including new universal variability searches in all SN Ia hosts, which yielded a total of 2200 variables with well-defined selection criteria, the largest such sample identified outside the Local Group. These objects are used in a companion paper to determine the local value of H0 with a total uncertainty of 2.4%. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.

  16. Hubble Space Telescope Eclipse Observations of the Nova Like Cataclysmic Variable UX Ursae Majoris

    Science.gov (United States)

    Knigge, Christian; Long, Knox S.; Wade, Richard A.; Baptista, Raymundo; Horne, Keith; Hubeny, Ivan; Rutten, Rene G. M.

    1998-01-01

    We present and analyze Hubble Space Telescope observations of the eclipsing nova-like cataclysmic variable UX UMa obtained with the Faint Object Spectrograph. Two eclipses each were observed with the G160L grating (covering the ultraviolet waveband) in 1994 August and with the PRISM (covering the near-ultraviolet to near-infrared) in November of the same year. The system was about 50% brighter in November than in August, which, if due to a change in the accretion rate, indicates a fairly substantial increase in Mass accretion by about 50%. The eclipse light curves are qualitatively consistent with the gradual occultation of an accretion disk with a radially decreasing temperature distribution. The light curves also exhibit asymmetries about mideclipse that are likely due to a bright spot at the disk edge. Bright-spot spectra have been constructed by differencing the mean spectra observed at pre- and posteclipse orbital phases. These difference spectra contain ultraviolet absorption lines and show the Balmer jump in emission. This suggests that part of the bright spot may be optically thin in the continuum and vertically extended enough to veil the inner disk and/or the outflow from UX UMa in some spectral lines. Model disk spectra constructed as ensembles of stellar atmospheres provide poor descriptions of the observed posteclipse spectra, despite the fact that UX UMa's light should be dominated by the disk at this time. Suitably scaled single temperature model stellar atmospheres with T(sub eff) approximately equals 12,500-14,500 K actually provide a better match to both the ultraviolet and optical posteclipse spectra. Evidently, great care must be taken in attempts to derive accretion rates from comparisons of disk models to observations. One way to reconcile disk models with the observed posteclipse spectra is to postulate the presence of a significant amount of optically thin material in the system. Such an optically thin component might be associated with the

  17. Wide-Field Hubble Space Telescope Observations of the Globular Cluster System in NGC 1399*

    Science.gov (United States)

    Puzia, Thomas H.; Paolillo, Maurizio; Goudfrooij, Paul; Maccarone, Thomas J.; Fabbiano, Giuseppina; Angelini, Lorella

    2014-01-01

    We present a comprehensive high spatial resolution imaging study of globular clusters (GCs) in NGC 1399, thecentral giant elliptical cD galaxy in the Fornax galaxy cluster, conducted with the Advanced Camera for Surveys(ACS) aboard theHubble Space Telescope(HST).Using a novel technique to construct drizzled point-spreadfunction libraries for HSTACS data, we accurately determine the fidelity of GC structural parameter measurementsfrom detailed artificial star cluster experiments and show the superior robustness of the GC half-light radius,rh,compared with other GC structural parameters, such as King core and tidal radius. The measurement ofrhfor themajor fraction of the NGC 1399 GC system reveals a trend of increasingrhversus galactocentric distance,Rgal,out to about 10 kpc and a flat relation beyond. This trend is very similar for blue and red GCs, which are found tohave a mean size ratio ofrh,redrh,blue0.820.11 at all galactocentric radii from the core regions of the galaxyout to40 kpc. This suggests that the size difference between blue and red GCs is due to internal mechanismsrelated to the evolution of their constituent stellar populations. Modeling the mass density profile of NGC 1399shows that additional external dynamical mechanisms are required to limit the GC size in the galaxy halo regionstorh2 pc. We suggest that this may be realized by an exotic GC orbit distribution function, an extended darkmatter halo, andor tidal stress induced by the increased stochasticity in the dwarf halo substructure at largergalactocentric distances. We compare our results with the GCrhdistribution functions in various galaxies and findthat the fraction of extended GCs withrh5 pc is systematically larger in late-type galaxies compared with GCsystems in early-type galaxies. This is likely due to the dynamically more violent evolution of early-type galaxies.We match our GCrhmeasurements with radial velocity data from the literature and split the resulting sample at

  18. Hubble Space Telescope Observations of Globular Clusters with Central Density Cusps

    Science.gov (United States)

    Sosin, Craig Anthony

    1997-07-01

    We use the Hubble Space Telescope to observe crowded fields in globular clusters with central density cusps, and use the observed stellar distributions to study the internal dynamics of clusters in advanced stages of evolution. We begin by discussing images of the cusp of NGC 6624. From the positions of individual stars, we measure the logarithmic slope of the central density cusp, but do not resolve the cluster core. We also detect a central population of blue stragglers, and compare the frequencies of such stars in several clusters. NGC 6397, as well as photometric techniques for use with diffraction-limited HST images. We measure logarithmic cusp slopes for various groups of main-sequence stars in each cluster; we also set upper limits on the core radii of M15 and M30, and measure a radius of ~5' for the NGC 6397 core. We compare mass functions (MFs) measured at several radii in each cluster, and find substantial mass segregation. In M30, the observed segregation is well matched by the predictions of a King-Michie model, but similar models of M15 and NGC 6397 predict more mass segregation than we observe. We then use the Jeans equation and our MFs to investigate the degree of equipartition of energy between stellar species in each cluster. We find that M30 is very close to equipartition over the observed radial range between the cusp and the envelope, while M15 and NGC 6397 are not. The difference between M30 and M15 might be explained by the difference in relaxation times at the observed radii, but this scenario fails to explain the NGC 6397 data. We discuss the possibility that post-collapse clusters remain subject to the Spitzer instability, and the possibility that the tidal shocks suffered by NGC 6397 have affected its degree of mass segregation. We also propose that the observed differences between the central cusps of the clusters could be due to gravothermal oscillations, to differences in binary populations, or to the presence of a ~103Msolar black hole

  19. HUBBLE SPACE TELESCOPE Observations of the Host Galaxy of GRB 970508

    Science.gov (United States)

    Fruchter, A. S.; Pian, E.; Gibbons, R.; Thorsett, S. E.; Ferguson, H.; Petro, L.; Sahu, K. C.; Livio, M.; Caraveo, P.; Frontera, F.; Kouveliotou, C.; Macchetto, D.; Palazzi, E.; Pedersen, H.; Tavani, M.; van Paradijs, J.

    2000-12-01

    We report on observations of the field of GRB 970508 made in 1998 early August, 454 days after outburst, with the STIS CCD camera on board the Hubble Space Telescope (HST). The images, taken in open filter (50CCD) mode, clearly reveal the presence of a galaxy that was overwhelmed in earlier (1997 June) HST images by emission from the optical transient (OT). The galaxy is regular in shape: after correcting for the HST/STIS PSF, it is well fitted by an exponential disk with a scale length of 0.046"+/-0.006" and an ellipticity of 0.70+/-0.07. All observations are marginally consistent with a continuous decline in OT emission as t-1.3 beginning 2 days after outburst; however, we find no direct evidence in the late-time HST image for emission from the OT, and the surface brightness profile of the galaxy is most regular if we assume that the OT emission is negligible, suggesting that the OT may have faded more rapidly at late times than is predicted by the power-law decay. Due to the wide bandwidth of the STIS clear mode, the estimated magnitude of the galaxy is dependent on the galaxy spectrum that is assumed. Using colors obtained from late-time ground-based observations to constrain the spectrum, we find V=25.4+/-0.15, a few tenths of a magnitude brighter than earlier ground-based estimates that were obtained by observing the total light of the galaxy and the OT and then subtracting the estimated OT brightness, assuming that it fades as a single power law. This again suggests that the OT may have faded faster at late time than the power law predicts. The position of the OT agrees with that of the isophotal center of the galaxy to 0.01", which, at the galaxy redshift z=0.83, corresponds to an offset from the center of the host of <~70 pc. This remarkable agreement raises the possibility that the gamma-ray burst may have been associated with either an active galactic nucleus or a nuclear starburst.

  20. A High-Resolution Hubble Space Telescope Study of Apparent Lyman Continuum Leakers at z~3

    Science.gov (United States)

    Mostardi, R. E.; Shapley, A. E.; Steidel, C. C.; Trainor, R. F.; Reddy, N. A.; Siana, B.

    2015-09-01

    We present U336V606J125H160 follow-up Hubble Space Telescope (HST) observations of 16 z ˜ 3 candidate Lyman continuum (LyC) emitters in the HS1549+1919 field. With these data, we obtain high spatial-resolution photometric redshifts of all sub-arcsecond components of the LyC candidates in order to eliminate foreground contamination and identify robust candidates for leaking LyC emission. Of the 16 candidates, we find one object with a robust LyC detection that is not due to foreground contamination. This object (MD5) resolves into two components; we refer to the LyC-emitting component as MD5b. MD5b has an observed 1500 Å to 900 Å flux-density ratio of {({F}{UV}/{F}{LyC})}{obs}=4.0+/- 2.0, compatible with predictions from stellar population synthesis models. Assuming minimal IGM absorption, this ratio corresponds to a relative (absolute) escape fraction of {f}{esc,{rel}}{MD5{{b}}} = 75%-100% ({f}{esc,{abs}}{MD5{{b}}} = 14%-19%). The stellar population fit to MD5b indicates an age of ≲50 Myr, which is in the youngest 10% of the HST sample and the youngest third of typical z ˜ 3 Lyman break galaxies, and may be a contributing factor to its LyC detection. We obtain a revised, contamination-free estimate for the comoving specific ionizing emissivity at z = 2.85, indicating (with large uncertainties) that star-forming galaxies provide roughly the same contribution as QSOs to the ionizing background at this redshift. Our results show that foreground contamination prevents ground-based LyC studies from obtaining a full understanding of LyC emission from z ˜ 3 star-forming galaxies. Future progress in direct LyC searches is contingent upon the elimination of foreground contaminants through high spatial-resolution observations, and upon acquisition of sufficiently deep LyC imaging to probe ionizing radiation in high-redshift galaxies.

  1. Impacts on the Hubble Space Telescope Wide Field and Planetary Camera 2: Experimental Simulation of Micrometeoroid Capture

    Science.gov (United States)

    Price, M. C.; Kearsley, A. T.; Wozniakiewicz, P. J.; Spratt, J.; Burchell, M. J.; Cole, M. J.; Anz-Meador, P.; Liou, J. C.; Ross, D. K.; Opiela, J.; hide

    2014-01-01

    Hypervelocity impact features have been recognized on painted surfaces returned from the Hubble Space Telescope (HST). Here we describe experiments that help us to understand their creation, and the preservation of micrometeoroid (MM) remnants. We simulated capture of silicate and sulfide minerals on the Zinc orthotitanate (ZOT) paint and Al alloy plate of the Wide Field and Planetary Camera 2 (WFPC2) radiator, which was returned from HST after 16 years in low Earth orbit (LEO). Our results also allow us to validate analytical methods for identification of MM (and orbital debris) impacts in LEO.

  2. Hubble Space telescope thermal cycle test report for large solar array samples with BSFR cells (Sample numbers 703 and 704)

    Science.gov (United States)

    Alexander, D. W.

    1992-01-01

    The Hubble space telescope (HST) solar array was designed to meet specific output power requirements after 2 years in low-Earth orbit, and to remain operational for 5 years. The array, therefore, had to withstand 30,000 thermal cycles between approximately +100 and -100 C. The ability of the array to meet this requirement was evaluated by thermal cycle testing, in vacuum, two 128-cell solar cell modules that exactly duplicated the flight HST solar array design. Also, the ability of the flight array to survive an emergency deployment during the dark (cold) portion of an orbit was evaluated by performing a cold-roll test using one module.

  3. Interferometric Astrometry with Hubble Space Telescope Fine Guidance Sensor 3 The Parallax of the Cataclysmic Variable TV Columbae

    CERN Document Server

    McArthur, B E; Lee, J; Van Altena, W F; Slesnick, C L; Rhee, J T; Patterson, R J; Fredrick, L W; Spiesman, W J; Nelan, E; Duncombe, R L; Hemenway, P D; Jefferys, W H; Shelus, P J; Franz, O G; Wasserman, L H

    2001-01-01

    TV Columbae (TV Col) is a 13th magnitude Intermediate Polar (IP) Cataclysmic Variable (CV), with multiple periods found in the light curves. Past estimates predicted a distance of 400 parsec to greater than 500 parsec. Recently completed Hubble Space Telescope (HST) Fine Guidance Sensor (FGS) interferometric observations allow us to determine the first trigonometric parallax to TV Col. This determination puts the distance of TV Col at 368 -15+17 parsecs. CD-32 2376, a 10th magnitude Tycho Catalog star, is a reference star in the TV Col frame. We find a distance of $127.7 -1+1 parsecs.

  4. The Black Hole Mass-Bulge Luminosity Relationship for Active Galactic Nuclei From Reverberation Mapping and Hubble Space Telescope Imaging

    DEFF Research Database (Denmark)

    Bentz, Misty C.; Peterson, Bradley M.; Pogge, Richard W.

    2009-01-01

    We investigate the relationship between black hole mass and bulge luminosity for active galactic nuclei (AGNs) with reverberation-based black hole mass measurements and bulge luminosities from two-dimensional decompositions of Hubble Space Telescope host galaxy images. We find that the slope...... of the relationship for AGNs is 0.76-0.85 with an uncertainty of ~0.1, somewhat shallower than the M BH vprop L 1.0±0.1 relationship that has been fit to nearby quiescent galaxies with dynamical black hole mass measurements. This difference is somewhat perplexing, as the AGN black hole masses include an overall...

  5. Hubble Space Telescope Discovery of a Probable Caustic-Crossing Event in the MACS1149 Galaxy Cluster Field

    Science.gov (United States)

    Kelly, Patrick L.; Rodney, Steven; Diego, Jose Maria; Zitrin, Adi; Broadhurst, Tom; Selsing, Jonatan; Balestra, Italo; Benito, Alberto Molino; Bradac, Marusa; Bradley, Larry; Brammer, Gabriel; Cenko, Brad; Christensen, Lise; Coe, Dan; Filippenko, Alexei V.; Foley, Ryan; Frye, Brenda; Graham, Melissa; Graur, Or; Grillo, Claudio; Hjorth, Jens; Howell, Andy; Jauzac, Mathilde; Jha, Saurabh; Kaiser, Nick; Kawamata, Ryota; Kneib, Jean-Paul; Lotz, Jennifer; Matheson, Thomas; McCully, Curtis; Merten, Julian; Nonino, Mario; Oguri, Masamune; Richard, Johan; Riess, Adam; Rosati, Piero; Schmidt, Kasper Borello; Sharon, Keren; Smith, Nathan; Strolger, Lou; Treu, Tommaso; Wang, Xin; Weiner, Ben; Williams, Liliya; Zheng, Weikang

    2016-05-01

    While monitoring the MACS1149 (z = 0.54) galaxy cluster as part of the RefsdalRedux program (PID 14199; PI Kelly) with the Hubble Space Telescope (HST) WFC3 IR camera, we have detected a rising transient that appears to be coincident ( Target-of-opportunity optical follow-up imaging in several ACS and WFC3 bands with the FrontierSN program (PID 14208; PI Rodney) has revealed that its rest-frame ultraviolet through optical spectrum may be reasonably well fit with that of a B star at z=1.49 exhibiting a strong Balmer break.

  6. Far-ultraviolet Spectroscopy of Recent Comets with the Cosmic Origins Spectrograph on the Hubble Space Telescope

    Science.gov (United States)

    Feldman, Paul D.; Weaver, Harold A.; A'Hearn, Michael F.; Combi, Michael R.; Dello Russo, Neil

    2016-10-01

    Since its launch in 1990, the Hubble Space Telescope (HST) has served as a platform with unique capabilities for remote observations of comets. Successive generations of imagers and spectrographs have seen large advances in sensitivity and spectral resolution enabling observations of the diverse properties of a representative number of comets during the past 25 years. To date, four comets have been observed in the far-ultraviolet by the Cosmic Origins Spectrograph (COS), the last spectrograph to be installed in HST, in 2009: 103P/Hartley 2, C/2009 P1 (Garradd), C/2012 S1 (ISON), and C/2014 Q2 (Lovejoy). COS has unprecedented sensitivity, albeit no spatial resolution, and the principal objective was to determine the relative CO abundance from measurements of the CO Fourth Positive system in the spectral range of 1400 to 1700 Å. In the two brightest comets, nineteen bands of this system were clearly identified. The water production rate was derived from nearly simultaneous observations of the OH (0,0) band at 3085 Å by the Space Telescope Imaging Spectrograph (STIS). The derived CO/H2O production rate ratio ranged from ~0.3% for Hartley 2 (Weaver et al., ApJ 734:L5, 2011) to ~20% for Garradd. In addition, strong partially resolved emission features due to multiplets of S I, centered at 1429 Å and 1479 Å, and of C I at 1561 Å and 1657 Å, were observed in all four comets. Weak emission from several lines of the H2 Lyman band system, excited by solar Lyman-α and Lyman-β pumped fluorescence, were detected in comet Lovejoy.This work is based on observations made with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. Support was provided by NASA through grants from the Space Telescope Science Institute.

  7. Analyses of Hubble Space Telescope Aluminized-Teflon Multilayer Insulation Blankets Retrieved After 19 Years of Space Exposure

    Science.gov (United States)

    de Groh, Kim K.; Perry, Bruce A.; Mohammed, Jelila S.; Banks, Bruce

    2015-01-01

    Since its launch in April 1990, the Hubble Space Telescope (HST) has made many important observations from its vantage point in low Earth orbit (LEO). However, as seen during five servicing missions, the outer layer of multilayer insulation (MLI) has become increasingly embrittled and has cracked in many areas. In May 2009, during the 5th servicing mission (called SM4), two MLI blankets were replaced with new insulation and the space-exposed MLI blankets were retrieved for degradation analyses by teams at NASA Glenn Research Center (GRC) and NASA Goddard Space Flight Center (GSFC). The retrieved MLI blankets were from Equipment Bay 8, which received direct sunlight, and Equipment Bay 5, which received grazing sunlight. Each blanket was divided into several regions based on environmental exposure and/or physical appearance. The aluminized-Teflon (DuPont, Wilmington, DE) fluorinated ethylene propylene (Al-FEP) outer layers of the retrieved MLI blankets have been analyzed for changes in optical, physical, and mechanical properties, along with chemical and morphological changes. Pristine and as-retrieved samples (materials) were heat treated to help understand degradation mechanisms. When compared to pristine material, the analyses have shown how the Al-FEP was severely affected by the space environment. Most notably, the Al-FEP was highly embrittled, fracturing like glass at strains of 1 to 8 percent. Across all measured properties, more significant degradation was observed for Bay 8 material as compared to Bay 5 material. This paper reviews the tensile and bend-test properties, density, thickness, solar absorptance, thermal emittance, x-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS) elemental composition measurements, surface and crack morphologies, and atomic oxygen erosion yields of the Al-FEP outer layer of the retrieved HST blankets after 19 years of space exposure.

  8. Hubble Space Telescope Servicing Mission Four (HST SM4) EVA Challenges for Safe Execution of STS-125

    Science.gov (United States)

    Dedalis, Robert P.; Hill, William H.; Rice, Karin Bergh; Cooter, Ann M.

    2010-01-01

    In May of 2009, the world-renowned Hubble Space Telescope (HST) received a suite of new instruments and a refurbished bus to enable science for many years to come. The restoration was conducted on-orbit by four space-walkers on five carefully scripted Extra-Vehicular Activity (EVA) days. Assuring the safety of the space-walkers and their crew-mates required careful attention to tool development, detailed procedures for every activity and many rehearsals with engineers and crew to ensure that everything worked together. Additionally, evolution of EVA requirements since the last servicing mission in 2002, and the broad scope of the mission demanded a much higher degree of safety participation in hardware design and risk acceptance than for previous servicing missions.

  9. Scaling Relations and Overabundance of Massive Clusters at z >~ 1 from Weak-lensing Studies with the Hubble Space Telescope

    Science.gov (United States)

    Jee, M. J.; Dawson, K. S.; Hoekstra, H.; Perlmutter, S.; Rosati, P.; Brodwin, M.; Suzuki, N.; Koester, B.; Postman, M.; Lubin, L.; Meyers, J.; Stanford, S. A.; Barbary, K.; Barrientos, F.; Eisenhardt, P.; Ford, H. C.; Gilbank, D. G.; Gladders, M. D.; Gonzalez, A.; Harris, D. W.; Huang, X.; Lidman, C.; Rykoff, E. S.; Rubin, D.; Spadafora, A. L.

    2011-08-01

    We present weak gravitational lensing analysis of 22 high-redshift (z >~ 1) clusters based on Hubble Space Telescope images. Most clusters in our sample provide significant lensing signals and are well detected in their reconstructed two-dimensional mass maps. Combining the current results and our previous weak-lensing studies of five other high-z clusters, we compare gravitational lensing masses of these clusters with other observables. We revisit the question whether the presence of the most massive clusters in our sample is in tension with the current ΛCDM structure formation paradigm. We find that the lensing masses are tightly correlated with the gas temperatures and establish, for the first time, the lensing mass-temperature relation at z >~ 1. For the power-law slope of the M-TX relation (MvpropT α), we obtain α = 1.54 ± 0.23. This is consistent with the theoretical self-similar prediction α = 3/2 and with the results previously reported in the literature for much lower redshift samples. However, our normalization is lower than the previous results by 20%-30%, indicating that the normalization in the M-TX relation might evolve. After correcting for Eddington bias and updating the discovery area with a more conservative choice, we find that the existence of the most massive clusters in our sample still provides a tension with the current ΛCDM model. The combined probability of finding the four most massive clusters in this sample after the marginalization over cosmological parameters is less than 1%. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555, under program 9290, 9919, and 10496.

  10. Near-infrared Emission Spectrum of WASP-103b Using Hubble Space Telescope/Wide Field Camera 3

    Science.gov (United States)

    Cartier, Kimberly M. S.; Beatty, Thomas G.; Zhao, Ming; Line, Michael; Ngo, Henry; Mawet, Dimitri; Stassun, Keivan G.; Wright, Jason T.; Kreidberg, Laura; Fortney, Jonathan; Knutson, Heather

    2017-01-01

    We present here our observations and analysis of the dayside emission spectrum of the hot Jupiter WASP-103b. We observed WASP-103b during secondary eclipse using two visits of the Hubble Space Telescope with the G141 grism on Wide Field Camera 3 in spatial scan mode. We generated secondary eclipse light curves of the planet in both blended white-light and spectrally binned wavechannels from 1.1 {to} 1.7 μ {{m}} and corrected the light curves for flux contamination from a nearby companion star. We modeled the detector systematics and secondary eclipse spectrum using Gaussian process regression and found that the near-IR emission spectrum of WASP-103b is featureless across the observed near-IR region to down to a sensitivity of 175 ppm, and shows a shallow slope toward the red. The atmosphere has a single brightness temperature of {T}{{B}}=2890 K across this wavelength range. This region of the spectrum is indistinguishable from isothermal, but may not manifest from a physically isothermal system, i.e., pseudo-isothermal. A solar-metallicity profile with a thermal inversion layer at 10‑2 bar fits the spectrum of WASP-103b with high confidence, as do an isothermal profile with solar metallicity and a monotonically decreasing atmosphere with C/O > 1. The data rule out a monotonically decreasing atmospheric profile with solar composition, and we rule out a low-metallicity decreasing profile as unphysical for this system. The pseudo-isothermal profile could be explained by a thermal inversion layer just above the layer probed by our observations, or by clouds or haze in the upper atmosphere. Transmission spectra at optical wavelengths would allow us to better distinguish between potential atmospheric models. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.

  11. Impacts on the Hubble Space Telescope Wide Field and Planetary Camera 2: Microanalysis and Recognition of Micrometeoroid Compositions

    Science.gov (United States)

    Kearsley, A. T.; Ross, D. K.; Anz-Meador, P.; Liou, J. C.; Opiela, J.; Grime, G. W.; Webb, R. P.; Jeynes, C.; Palitsin, V. V.; Colaux, J. L.; hide

    2014-01-01

    Postflight surveys of the Wide Field and Planetary Camera 2 (WFPC2) on the Hubble Space Telescope have located hundreds of features on the 2.2 by 0.8 m curved plate, evidence of hypervelocity impact by small particles during 16 years of exposure to space in low Earth orbit (LEO). The radiator has a 100 - 200 micron surface layer of white paint, overlying 4 mm thick Al alloy, which was not fully penetrated by any impact. Over 460 WFPC2 samples were extracted by coring at JSC. About half were sent to NHM in a collaborative program with NASA, ESA and IBC. The structural and compositional heterogeneity at micrometer scale required microanalysis by electron and ion beam microscopes to determine the nature of the impactors (artificial orbital debris, or natural micrometeoroids, MM). Examples of MM impacts are described elsewhere. Here we describe the development of novel electron beam analysis protocols, required to recognize the subtle traces of MM residues.

  12. Precise Estimates of the Physical Parameters for the Exoplanet System HD 17156 Enabled by Hubble Space Telescope Fine Guidance Sensor Transit and Asteroseismic Observations

    DEFF Research Database (Denmark)

    Nutzman, Philip; Gilliland, Ronald L.; McCullough, Peter R.

    2011-01-01

    We present observations of three distinct transits of HD 17156b obtained with the Fine Guidance Sensors on board the Hubble Space Telescope. We analyzed both the transit photometry and previously published radial velocities to find the planet-star radius ratio Rp /R sstarf = 0.07454 ± 0.00035, in......We present observations of three distinct transits of HD 17156b obtained with the Fine Guidance Sensors on board the Hubble Space Telescope. We analyzed both the transit photometry and previously published radial velocities to find the planet-star radius ratio Rp /R sstarf = 0.07454 ± 0...

  13. Space Telescope and Optical Reverberation Mapping Project. I. Ultraviolet Observations of the Seyfert 1 Galaxy NGC 5548 with the Cosmic Origins Spectrograph on Hubble Space Telescope

    CERN Document Server

    De Rosa, G; Ely, J; Kriss, G A; Crenshaw, D M; Horne, Keith; Korista, K T; Netzer, H; Pogge, R W; Arevalo, P; Barth, A J; Bentz, M C; Brandt, W N; Breeveld, A A; Brewer, B J; Bonta, E Dalla; De Lorenzo-Caceres, A; Denney, K D; Dietrich, M; Edelson, R; Evans, P A; Fausnaugh, M M; Gehrels, N; Gelbord, J M; Goad, M R; Grier, C J; Grupe, D; Hall, P B; Kaastra, J; Kelly, B C; Kennea, J A; Kochanek, C S; Lira, P; Mathur, S; McHardy, I M; Nousek, J A; Pancoast, A; Papadakis, I; Pei, L; Schimoia, J S; Siegel, M; Starkey, D; Treu, T; Uttley, P; Vaughan, S; Vestergaard, M; Villforth, C; Yan, H; Young, S; Zu, Y

    2015-01-01

    We describe the first results from a six-month long reverberation-mapping experiment in the ultraviolet based on 170 observations of the Seyfert 1 galaxy NGC 5548 with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Significant correlated variability is found in the continuum and broad emission lines, with amplitudes ranging from ~30% to a factor of two in the emission lines and a factor of three in the continuum. The variations of all the strong emission lines lag behind those of the continuum, with He II 1640 lagging behind the continuum by ~2.5 days and Lyman alpha 1215, C IV 1550, and Si IV 1400 lagging by ~5-6 days. The relationship between the continuum and emission lines is complex. In particular, during the second half of the campaign, all emission-line lags increased by a factor of 1.3-2 and differences appear in the detailed structure of the continuum and emission-line light curves. Velocity-resolved cross-correlation analysis shows coherent structure in lag versus line-of-sight veloc...

  14. Effects of Heating on Teflon(Registered Trademark) FEP Thermal Control Material from the Hubble Space Telescope

    Science.gov (United States)

    deGroh, Kim; Gaier, James R.; Hall, Rachelle L.; Norris, Mary Jo; Espe, Matthew P.; Cato, Daveen R.

    1999-01-01

    Metallized Teflon(Registered Trademark) FEP (fluorinated ethylene propylene) thermal control material on the Hubble Space Telescope (HST) is degrading in the space environment. Teflon(Registered Trademark) FEP thermal control blankets (space-facing FEP) retrieved during the first servicing mission (SM1) were found to be embrittled on solar facing surfaces and contained microscopic cracks. During the second servicing mission (SM2) astronauts noticed that the FEP outer layer of the multi-layer insulation (MLI) covering the telescope was cracked in many locations around the telescope. Large cracks were observed on the light shield, forward shell and equipment bays. A tightly curled piece of cracked FEP from the light shield was retrieved during SM2 and was severely embrittled, as witnessed by ground testing. A Failure Review Board (FRB) was organized to determine the mechanism causing the MLI degradation. Density, x-ray crystallinity and solid state nuclear magnetic resonance (NMR) analyses of FEP retrieved during SM1 were inconsistent with results of FEP retrieved during SM2. Because the retrieved SM2 material curled while in space, it experienced a higher temperature extreme during thermal cycling, estimated at 200 C, than the SM1 material, estimated at 50 C. An investigation on the effects of heating pristine and FEP exposed on HST was therefore conducted. Samples of pristine. SM1, and SM2 FEP were heated to 200 C and evaluated for changes in density and morphology. Elevated temperature exposure was found to have a major impact on the density of the retrieved materials. Characterization of polymer morphology of as-received and heated FEP samples by NMR provided results that were consistent with the density results. These findings have provided insight to the damage mechanisms of FEP in the space environment.

  15. New Understanding of Hubble Space Telescope Gyro Current Increase Led to a Method to Save a Failing Gyro Presentation

    Science.gov (United States)

    Blumenstock, Kenneth A.

    2017-01-01

    Throughout the history of the Hubble Space Telescope (HST) program, gyro current increases have been observed to occur, often times leading to gyro failure. The explanation was that debris from the surfaces of the gas bearings, with only 1.27 micron clearance, resulted in rotor restriction, which increased friction, torque, and current. However, the rotor restriction theory never could account for the fact that a restart of the gyro would restore the current back to nominal. An effort was made to understand this puzzling gyro behavior after two HST gyros exhibited increased current within the same week in November 2015. A review board was created to resolve these anomalies and generate operational procedures to potentially extend gyro life. A new understanding of gyro current behavior led to implementation of a method that could potentially save a failing gyro.

  16. New Understanding of Hubble Space Telescope Gyro Current Increase Led to a Method to Save a Failing Gyro

    Science.gov (United States)

    Blumenstock, Kenneth A.

    2017-01-01

    Throughout the history of the Hubble Space Telescope (HST) program, gyro current increases have been observed to occur, oftentimes leading to gyro failure. The explanation was that debris from the surfaces of the gas bearings, with only 50 millionths on an inch clearance, resulted in rotor restriction, which increased friction, torque, and current. However, the rotor restriction theory never could account for the fact that a restart of the gyro would restore the current back to nominal. An effort was made to understand this puzzling gyro behavior after two HST gyros exhibited increased current within the same week in November 2015. A review board was created to resolve these anomalies and generate operational procedures to potentially extend gyro life.

  17. Optical Identification of Cepheids in 19 Host Galaxies of Type Ia Supernovae and NGC 4258 with the Hubble Space Telescope

    CERN Document Server

    Hoffmann, Samantha L; Riess, Adam G; Yuan, Wenlong; Casertano, Stefano; Filippenko, Alexei V; Tucker, Brad E; Chornock, Ryan; Silverman, Jeffrey M; Welch, Douglas L; Goobar, Ariel; Amanullah, Rahman

    2016-01-01

    We present results of an optical search for Cepheid variable stars using the Hubble Space Telescope (HST) in 19 hosts of Type Ia supernovae (SNe Ia) and the maser-host galaxy NGC 4258, conducted as part of the SH0ES project (Supernovae and H0 for the Equation of State of dark energy). The targets include 9 newly imaged SN Ia hosts using a novel strategy based on a long-pass filter that minimizes the number of HST orbits required to detect and accurately determine Cepheid properties. We carried out a homogeneous reduction and analysis of all observations, including new universal variability searches in all SN Ia hosts, that yielded a total of 2200 variables with well-defined selection criteria -- the largest such sample identified outside the Local Group. These objects are used in a companion paper to determine the local value of H0 with a total uncertainty of 2.4%.

  18. Lisp Object State Saver (LOSS): A facility used to save partial schedules of the Hubble Space Telescope

    Science.gov (United States)

    Sponsler, Jeffrey L.

    1988-01-01

    Current research in the area of long term scheduling of the Hubble Space Telescope is being done using Common Lisp and Flavors on Lisp Machines. The planning tools manipulate memory-resident data structures which represent the many entities and relationships that represent planning states. The Lisp Object State Saver (LOSS), a general purpose utility, was constructed which allows one to take a snapshot of memory by storing a representation of the structures in a text file. This text file can later be loaded thus restoring the pre-existing and logically equivalent planning state. A LOSS template must be created for each datatype to be stored and a simple grammar governs the creation of such templates.

  19. The History and Environment of a Faded Quasar: Hubble Space Telescope observations of Hanny's Voorwerp and IC 2497

    CERN Document Server

    Keel, William C; Schawinski, Kevin; Bennert, Vardha N; Thomas, Daniel; Manning, Anna; Chojnowski, S Drew; van Arkel, Hanny; Lynn, Stuart

    2012-01-01

    We present Hubble Space Telescope imaging and spectroscopy for the extended high-ionization cloud known as Hanny's Voorwerp, near the spiral galaxy IC 2497. WFC3 images show complex dust absorption near the nucleus of IC 2497. STIS spectra show a type 2 Seyfert AGN of rather low luminosity. The ionization parameter log U = -3.5 is in accord with its weak X-ray emission. We find no high-ionization gas near the nucleus, adding to evidence that the AGN is currently at low radiative output (perhaps now dominated by kinetic energy). The nucleus is accompanied by an expanding ring of ionized gas 500 pc in projected diameter on the side opposite Hanny's Voorwerp, with Doppler offset 300 km/s from the nucleus (kinematic age 100 (and possibly much more) within the last 1-2 x 10^5 years; we suggest a sequence of events and discuss implications of such rapid fluctuations for AGN demographics. (Abridged)

  20. THE HUBBLE SPACE TELESCOPE UV LEGACY SURVEY OF GALACTIC GLOBULAR CLUSTERS. III. A QUINTUPLE STELLAR POPULATION IN NGC 2808

    Energy Technology Data Exchange (ETDEWEB)

    Milone, A. P.; Marino, A. F.; Jerjen, H. [Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston, ACT, 2611 (Australia); Piotto, G. [Istituto Nazionale di Astrofisica—Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, Padova, IT-35122 (Italy); Renzini, A.; Bedin, L. R. [Dipartimento di Fisica e Astronomia “Galileo Galilei,” Univ. di Padova, Vicolo dell’Osservatorio 3, Padova, IT-35122 (Italy); Anderson, J.; Bellini, A. [Space Telescope Science Institute, 3800 San Martin Drive, Baltimore, MD 21218 (United States); Cassisi, S.; Pietrinferni, A. [Istituto Nazionale di Astrofisica—Osservatorio Astronomico di Teramo, Via Mentore Maggini s.n.c., I-64100 Teramo (Italy); D’Antona, F.; Ventura, P. [Istituto Nazionale di Astrofisica—Osservatorio Astronomico di Roma, Via Frascati 33, I-00040 Monteporzio Catone, Roma (Italy)

    2015-07-20

    In this study we present the first results from multi-wavelength Hubble Space Telescope (HST) observations of the Galactic globular cluster (GC) NGC 2808 as an extension of the Hubble Space Telescope UV Legacy Survey of Galactic GCs (GO-13297 and previous proprietary and HST archive data). Our analysis allowed us to disclose a multiple-stellar-population phenomenon in NGC 2808 even more complex than previously thought. We have separated at least five different populations along the main sequence and the red giant branch (RGB), which we name A, B, C, D, and E (though an even finer subdivision may be suggested by the data). We identified the RGB bump in four out of the five RGBs. To explore the origin of this complex color–magnitude diagram, we have combined our multi-wavelength HST photometry with synthetic spectra, generated by assuming different chemical compositions. The comparison of observed colors with synthetic spectra suggests that the five stellar populations have different contents of light elements and helium. Specifically, if we assume that NGC 2808 is homogeneous in [Fe/H] (as suggested by spectroscopy for Populations B, C, D, E, but lacking for Population A) and that population A has a primordial helium abundance, we find that populations B, C, D, E are enhanced in helium by ΔY ∼ 0.03, 0.03, 0.08, 0.13, respectively. We obtain similar results by comparing the magnitude of the RGB bumps with models. Planned spectroscopic observations will test whether Population A also has the same metallicity, or whether its photometric differences with Population B can be ascribed to small [Fe/H] and [O/H] differences rather than to helium.

  1. A Hubble Space Telescope Survey of Intrinsic Absorption in Nearby AGN

    Science.gov (United States)

    Dashtamirova, Dzhuliya; Dunn, Jay P.; Crenshaw, D. Michael

    2017-01-01

    We present a survey of the intrinsic UV absorption lines in active galactic nuclei (AGN). We limit our study to the ultraviolet spectra of type 1 AGN with a redshift of z COS) observations. We download and co-add all of the COS spectra. We find that about 80 of these are type 1 AGN. We normalize the COS spectra and identify all of the intrinsic Lyman-alpha, N V, Si IV, and C IV intrinsic absorption features. From these data, we determine the fraction of type 1 AGN with intrinsic absorption in this redshift range and find the global covering factors of the absorbers. We also identify low ionization species as well as excited state lines. A number of objects have multiple epoch COS and/or Space Telescope Imaging Spectrograph (STIS) observations, which we use to investigate the absorption variability.

  2. Jupiter After the 2009 Impact: Hubble Space Telescope Imaging of the Impact-Generated Debris and Its Temporal Evolution

    Science.gov (United States)

    Hammel, H. B.; Wong, M. H.; Clarke, J. T.; de Pater, I.; Fletcher, L. N.; Hueso, R.; Noll, K.; Orton, G. S.; Perez-Hoyos, S.; Sanchez-Lavega, A.; Simon-Miller, A. A.; Yanamandra-Fisher, P. A.

    2010-01-01

    We report Hubble Space Telescope images of Jupiter during the aftermath of an impact by an unknown object in 2009 July, The 2009 impact-created debris field evolved more slowly than those created in 1994 by the collision of the tidally disrupted comet D/Shoemaker-Levy 9 (SL9). The slower evolution, in conjunction with the isolated nature of this single impact, permits a more detailed assessment of the altitudes and meridional motion of the debris than was possible with SL9. The color of the 2009 debris was markedly similar to that seen in 1994, thus this dark debris is likely to be Jovian material that is highly thermally processed. The 2009 impact site differed from the 1994 SL9 sites in UV morphology and contrast lifetime; both are suggestive of the impacting body being asteroidal rather than cometary. Transport of the 2009 Jovian debris as imaged by Hubble shared similarities with transport of volcanic aerosols in Earth's atmosphere after major eruptions.

  3. A Type Ia Supernova at Redshift 1.55 in Hubble Space Telescope Infrared Observations from CANDELS

    CERN Document Server

    Rodney, Steven A; Dahlen, Tomas; Strolger, Louis-Gregory; Ferguson, Henry C; Hjorth, Jens; Frederiksen, Teddy F; Weiner, Benjamin J; Mobasher, Bahram; Casertano, Stefano; Jones, David O; Challis, Peter; Faber, S M; Filippenko, Alexei V; Garnavich, Peter; Graur, Or; Grogin, Norman A; Hayden, Brian; Jha, Saurabh W; Kirshner, Robert P; Kocevski, Dale; Koekemoer, Anton; McCully, Curtis; Patel, Brandon; Rajan, Abhijith; Scarlata, Claudia

    2012-01-01

    We report the discovery of a Type Ia supernova (SNIa) at redshift z=1.55 with the infrared detector of the Wide Field Camera 3 (WFC3-IR) on the Hubble Space Telescope (HST). This object was discovered in CANDELS imaging data of the Hubble Ultra Deep Field, and followed as part of the CANDELS+CLASH Supernova project, comprising the SN search components from those two HST multi-cycle treasury programs. This is the highest redshift SNIa with direct spectroscopic evidence for classification. It is also the first SN Ia at z>1 found and followed in the infrared, providing a full light curve in rest-frame optical bands. The classification and redshift are securely defined from a combination of multi-band and multi-epoch photometry of the SN, ground-based spectroscopy of the host galaxy, and WFC3-IR grism spectroscopy of both the SN and host. This object is the first of a projected sample at z>1.5 that will be discovered by the CANDELS and CLASH programs. The full CANDELS+CLASH SN Ia sample will enable unique tests f...

  4. Jupiter After the 2009 Impact: Hubble Space Telescope Imaging of the Impact-Generated Debris and Its Temporal Evolution

    Science.gov (United States)

    Hammel, H. B.; Wong, M. H.; Clarke, J. T.; de Pater, I.; Fletcher, L. N.; Hueso, R.; Noll, K.; Orton, G. S.; Perez-Hoyos, S.; Sanchez-Lavega, A.; hide

    2010-01-01

    We report Hubble Space Telescope images of Jupiter during the aftermath of an impact by an unknown object in 2009 July, The 2009 impact-created debris field evolved more slowly than those created in 1994 by the collision of the tidally disrupted comet D/Shoemaker-Levy 9 (SL9). The slower evolution, in conjunction with the isolated nature of this single impact, permits a more detailed assessment of the altitudes and meridional motion of the debris than was possible with SL9. The color of the 2009 debris was markedly similar to that seen in 1994, thus this dark debris is likely to be Jovian material that is highly thermally processed. The 2009 impact site differed from the 1994 SL9 sites in UV morphology and contrast lifetime; both are suggestive of the impacting body being asteroidal rather than cometary. Transport of the 2009 Jovian debris as imaged by Hubble shared similarities with transport of volcanic aerosols in Earth's atmosphere after major eruptions.

  5. Parallax Beyond a Kiloparsec from Spatially Scanning the Wide Field Camera 3 on the Hubble Space Telescope

    CERN Document Server

    Riess, Adam G; Anderson, Jay; Mackenty, John; Filippenko, Alexei V

    2014-01-01

    We use a newly developed observing mode on the Hubble Space Telescope (HST) and Wide Field Camera 3 (WFC3), spatial scanning, to increase source sampling a thousand-fold and measure changes in source positions to a precision of 20--40 microarcseconds, more than an order of magnitude better than attainable in pointed observations. This observing mode can usefully measure the parallaxes of bright stars at distances of up to 5 kpc, a factor of ten farther than achieved thus far with HST. Long-period classical Cepheid variable stars in the Milky Way, nearly all of which reside beyond 1 kpc, are especially compelling targets for parallax measurements from scanning, as they may be used to anchor a determination of the Hubble constant to ~1%. We illustrate the method by measuring to high precision the parallax of a classical Cepheid, SY Aurigae, at a distance of more than 2 kpc, using 5 epochs of spatial-scan data obtained at intervals of 6 months. Rapid spatial scans also enable photometric measurements of bright M...

  6. Hubble Space Telescope Studies of Nearby Type Ia Supernovae: The Mean Maximum Light Ultraviolet Spectrum and its Dispersion

    CERN Document Server

    Cooke, Jeff; Sullivan, Mark; Nugent, Peter; Howell, D Andrew; Gal-Yam, Avishay; Lidman, Chris; Bloom, Joshua S; Cenko, S Bradley; Kasliwal, Mansi M; Kulkarni, Shrinivas R; Law, Nicholas M; Ofek, Eran O; Quimby, Robert M

    2010-01-01

    We present the first results of an ongoing campaign using the STIS spectrograph on-board the Hubble Space Telescope (HST) whose primary goal is the study of near ultraviolet (UV) spectra of local Type Ia supernovae (SNe Ia). Using events identified by the Palomar Transient Factory and subsequently verified by ground-based spectroscopy, we demonstrate the ability to locate and classify SNe Ia as early as 16 days prior to maximum light. This enables us to trigger HST in a non-disruptive mode to obtain near UV spectra within a few days of maximum light for comparison with earlier equivalent ground-based spectroscopic campaigns conducted at intermediate redshifts, z ~ 0.5. We analyze the spectra of 12 Type Ia supernovae located in the Hubble flow with 0.01 < z < 0.08. Although a fraction of our eventual sample, these data, together with archival data, already provide a substantial advance over that previously available. Restricting samples to those of similar phase and stretch, the mean UV spectrum agrees r...

  7. Space Telescope.

    Science.gov (United States)

    National Aeronautics and Space Administration, Huntsville, AL. George C. Marshall Space Flight Center.

    This pamphlet describes the Space Telescope, an unmanned multi-purpose telescope observatory planned for launch into orbit by the Space Shuttle in the 1980s. The unique capabilities of this telescope are detailed, the major elements of the telescope are described, and its proposed mission operations are outlined. (CS)

  8. Hubble Space Telescope Near-Ultraviolet Spectroscopy of the Bright CEMP-no Star BD+44 493

    CERN Document Server

    Placco, Vinicius; Roederer, Ian; Cowan, John; Frebel, Anna; Filler, Dan; Ivans, Inese I; Lawler, James E; Schatz, Hendrik; Sneden, Christopher; Sobeck, Jennifer; Aoki, Wako; Smith, Verne

    2014-01-01

    We present an elemental-abundance analysis, in the near-ultraviolet (NUV) spectral range, for the extremely metal-poor star BD+44 493, a 9th magnitude sub-giant with [Fe/H] = -3.8 and enhanced carbon, based on data acquired with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. This star is the brightest example of a class of objects that, unlike the great majority of carbon-enhanced metal-poor (CEMP) stars, does not exhibit over-abundances of heavy neutron-capture elements (CEMP-no). In this paper, we validate the abundance determinations for a number of species that were previously studied in the optical region, and obtain strong upper limits for beryllium and boron, as well as for neutron-capture elements from zirconium to platinum, many of which are not accessible from ground-based spectra. The boron upper limit we obtain for BD+44 493, logeps(B) < -0.70, the first such measurement for a CEMP star, is the lowest yet found for very and extremely metal-poor stars. In addition, we ob...

  9. A Hubble Space Telescope Search for a Sub-Earth-Sized Exoplanet in the GJ 436 System

    CERN Document Server

    Stevenson, Kevin B; Fabrycky, Daniel; Kreidberg, Laura

    2014-01-01

    The detection of small planets orbiting nearby stars is an important step towards the identification of Earth twins. In previous work using the Spitzer Space Telescope, we found evidence to support at least one sub-Earth-sized exoplanet orbiting the nearby mid-M dwarf star GJ 436. As a follow up, here we used the Hubble Space Telescope to investigate the existence of one of these candidate planets, UCF-1.01, by searching for two transit signals as it passed in front of its host star. Interpretation of the data hinges critically on correctly modeling and removing the WFC3 instrument systematics from the light curves. Building on previous HST work, we demonstrate that WFC3 analyses need to explore the use of a quadratic function to fit a visit-long time-dependent systematic. This is important for establishing absolute transit and eclipse depths in the white light curves of all transiting systems. The work presented here exemplifies this point by putatively detecting the primary transit of UCF-1.01 with the use ...

  10. Hubble Space Telescope ultraviolet spectroscopy of the hottest known helium-rich pre-white dwarf KPD0005+5106

    CERN Document Server

    Werner, K

    2015-01-01

    We present a model atmosphere analysis of ultraviolet echelle spectra of KPD0005+5106 taken with the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope. The star is the hottest known pre-white dwarf (Teff = 200,000+-20,000 K, log g = 6.7+-0.3; Wassermann et al. 2010). Its atmosphere is composed of helium with trace amounts of metals. It is of the so-called O(He) spectral type that comprises very hot helium-rich pre-white dwarfs whose origin is debated. From neon and silicon ionisation balances, we derive tighter constraints on the effective temperature (195,000+-15,000 K) and improve previous abundance determinations of these elements. We confirm the idea that KPD0005+5106 is the descendant of an R Coronae Borealis (RCB) star and, hence, is the outcome of a binary-white dwarf merger. We discuss the relation of KPD0005+5106 to other O(He) and RCB stars.

  11. The Extragalactic Distance Scale Key Project III. Teh discovery of Cephids and a New Distance to M101 Using the Hubble Space Telescope

    Science.gov (United States)

    Kelson, Daniel D.; Madore, Barry

    1994-01-01

    We report on the discovery of 29 cephid variables in the galaxy M101 after using the original Wide Field Camera (WFC 1) and the new Wide Field and Planetary Camera (WFPC 2) on the Hubble Space Telescope (HST), to observe a field in M101 at 14 independent epochs in F555W.

  12. CANDELS : THE COSMIC ASSEMBLY NEAR-INFRARED DEEP EXTRAGALACTIC LEGACY SURVEY-THE HUBBLE SPACE TELESCOPE OBSERVATIONS, IMAGING DATA PRODUCTS, AND MOSAICS

    NARCIS (Netherlands)

    Koekemoer, Anton M.; Faber, S. M.; Ferguson, Henry C.; Grogin, Norman A.; Kocevski, Dale D.; Koo, David C.; Lai, Kamson; Lotz, Jennifer M.; Lucas, Ray A.; McGrath, Elizabeth J.; Ogaz, Sara; Rajan, Abhijith; Riess, Adam G.; Rodney, Steve A.; Strolger, Louis; Casertano, Stefano; Castellano, Marco; Dahlen, Tomas; Dickinson, Mark; Dolch, Timothy; Fontana, Adriano; Giavalisco, Mauro; Grazian, Andrea; Guo, Yicheng; Hathi, Nimish P.; Huang, Kuang-Han; van der Wel, Arjen; Yan, Hao-Jing; Acquaviva, Viviana; Alexander, David M.; Almaini, Omar; Ashby, Matthew L. N.; Barden, Marco; Bell, Eric F.; Bournaud, Frederic; Brown, Thomas M.; Caputi, Karina I.; Cassata, Paolo; Challis, Peter J.; Chary, Ranga-Ram; Cheung, Edmond; Cirasuolo, Michele; Conselice, Christopher J.; Cooray, Asantha Roshan; Croton, Darren J.; Daddi, Emanuele; Dave, Romeel; de Mello, Duilia F.; de Ravel, Loic; Dekel, Avishai; Donley, Jennifer L.; Dunlop, James S.; Dutton, Aaron A.; Elbaz, David; Fazio, Giovanni G.; Filippenko, Alexei V.; Finkelstein, Steven L.; Frazer, Chris; Gardner, Jonathan P.; Garnavich, Peter M.; Gawiser, Eric; Gruetzbauch, Ruth; Hartley, Will G.; Haeussler, Boris; Herrington, Jessica; Hopkins, Philip F.; Huang, Jia-Sheng; Jha, Saurabh W.; Johnson, Andrew; Kartaltepe, Jeyhan S.; Khostovan, Ali A.; Kirshner, Robert P.; Lani, Caterina; Lee, Kyoung-Soo; Li, Weidong; Madau, Piero; McCarthy, Patrick J.; McIntosh, Daniel H.; McLure, Ross J.; McPartland, Conor; Mobasher, Bahram; Moreira, Heidi; Mortlock, Alice; Moustakas, Leonidas A.; Mozena, Mark; Nandra, Kirpal; Newman, Jeffrey A.; Nielsen, Jennifer L.; Niemi, Sami; Noeske, Kai G.; Papovich, Casey J.; Pentericci, Laura; Pope, Alexandra; Primack, Joel R.; Ravindranath, Swara; Reddy, Naveen A.; Renzini, Alvio; Rix, Hans-Walter; Robaina, Aday R.; Rosario, David J.; Rosati, Piero; Salimbeni, Sara; Scarlata, Claudia; Siana, Brian; Simard, Luc; Smidt, Joseph; Snyder, Diana; Somerville, Rachel S.; Spinrad, Hyron; Straughn, Amber N.; Telford, Olivia; Teplitz, Harry I.; Trump, Jonathan R.; Vargas, Carlos; Villforth, Carolin; Wagner, Cory R.; Wandro, Pat; Wechsler, Risa H.; Weiner, Benjamin J.; Wiklind, Tommy; Wild, Vivienne; Wilson, Grant; Wuyts, Stijn; Yun, Min S.

    2011-01-01

    This paper describes the Hubble Space Telescope imaging data products and data reduction procedures for the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). This survey is designed to document the evolution of galaxies and black holes at z approximate to 1.5-8, and to study

  13. CANDELS : THE COSMIC ASSEMBLY NEAR-INFRARED DEEP EXTRAGALACTIC LEGACY SURVEY-THE HUBBLE SPACE TELESCOPE OBSERVATIONS, IMAGING DATA PRODUCTS, AND MOSAICS

    NARCIS (Netherlands)

    Koekemoer, Anton M.; Faber, S. M.; Ferguson, Henry C.; Grogin, Norman A.; Kocevski, Dale D.; Koo, David C.; Lai, Kamson; Lotz, Jennifer M.; Lucas, Ray A.; McGrath, Elizabeth J.; Ogaz, Sara; Rajan, Abhijith; Riess, Adam G.; Rodney, Steve A.; Strolger, Louis; Casertano, Stefano; Castellano, Marco; Dahlen, Tomas; Dickinson, Mark; Dolch, Timothy; Fontana, Adriano; Giavalisco, Mauro; Grazian, Andrea; Guo, Yicheng; Hathi, Nimish P.; Huang, Kuang-Han; van der Wel, Arjen; Yan, Hao-Jing; Acquaviva, Viviana; Alexander, David M.; Almaini, Omar; Ashby, Matthew L. N.; Barden, Marco; Bell, Eric F.; Bournaud, Frederic; Brown, Thomas M.; Caputi, Karina I.; Cassata, Paolo; Challis, Peter J.; Chary, Ranga-Ram; Cheung, Edmond; Cirasuolo, Michele; Conselice, Christopher J.; Cooray, Asantha Roshan; Croton, Darren J.; Daddi, Emanuele; Dave, Romeel; de Mello, Duilia F.; de Ravel, Loic; Dekel, Avishai; Donley, Jennifer L.; Dunlop, James S.; Dutton, Aaron A.; Elbaz, David; Fazio, Giovanni G.; Filippenko, Alexei V.; Finkelstein, Steven L.; Frazer, Chris; Gardner, Jonathan P.; Garnavich, Peter M.; Gawiser, Eric; Gruetzbauch, Ruth; Hartley, Will G.; Haeussler, Boris; Herrington, Jessica; Hopkins, Philip F.; Huang, Jia-Sheng; Jha, Saurabh W.; Johnson, Andrew; Kartaltepe, Jeyhan S.; Khostovan, Ali A.; Kirshner, Robert P.; Lani, Caterina; Lee, Kyoung-Soo; Li, Weidong; Madau, Piero; McCarthy, Patrick J.; McIntosh, Daniel H.; McLure, Ross J.; McPartland, Conor; Mobasher, Bahram; Moreira, Heidi; Mortlock, Alice; Moustakas, Leonidas A.; Mozena, Mark; Nandra, Kirpal; Newman, Jeffrey A.; Nielsen, Jennifer L.; Niemi, Sami; Noeske, Kai G.; Papovich, Casey J.; Pentericci, Laura; Pope, Alexandra; Primack, Joel R.; Ravindranath, Swara; Reddy, Naveen A.; Renzini, Alvio; Rix, Hans-Walter; Robaina, Aday R.; Rosario, David J.; Rosati, Piero; Salimbeni, Sara; Scarlata, Claudia; Siana, Brian; Simard, Luc; Smidt, Joseph; Snyder, Diana; Somerville, Rachel S.; Spinrad, Hyron; Straughn, Amber N.; Telford, Olivia; Teplitz, Harry I.; Trump, Jonathan R.; Vargas, Carlos; Villforth, Carolin; Wagner, Cory R.; Wandro, Pat; Wechsler, Risa H.; Weiner, Benjamin J.; Wiklind, Tommy; Wild, Vivienne; Wilson, Grant; Wuyts, Stijn; Yun, Min S.

    2011-01-01

    This paper describes the Hubble Space Telescope imaging data products and data reduction procedures for the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). This survey is designed to document the evolution of galaxies and black holes at z approximate to 1.5-8, and to study

  14. The Hubble Space Telescope/Advanced Camera for Surveys Atlas of Protoplanetary Disks in the Great Orion Nebula

    Science.gov (United States)

    Ricci, L.; Robberto, M.; Soderblom, D. R.

    2008-11-01

    We present the atlas of protoplanetary disks in the Orion Nebula based on the Wide Field Channel of the Advanced Camera for Surveys (ACS/WFC) images obtained for the Hubble Space Telescope (HST) Treasury Program on the Orion Nebula Cluster. The observations have been carried out in five photometric filters nearly equivalent to the standard B, V, Hα, I, and z passbands. Our master catalog lists 178 externally ionized protoplanetary disks (proplyds), 28 disks seen only in absorption against the bright nebular background (silhouette disks), eight disks seen only as dark lanes at the midplane of extended polar emission (bipolar nebulae or reflection nebulae), and five sources showing jet emission with no evidence of either external ionized gas emission or dark silhouette disks. Many of these disks are associated with jets seen in Hα and circumstellar material detected through reflection emission in our broadband filters; approximately two-thirds have identified counterparts in X-rays. A total of 47 objects (29 proplyds, seven silhouette disks, six bipolar nebulae, five jets with no evidence of proplyd emission or silhouette disk) are new detections with HST. We include in our list four objects previously reported as circumstellar disks, which have not been detected in our HST/ACS images either because they are hidden by the bleeding trails of a nearby saturated bright star or because of their location out of the HST/ACS Treasury Program field. The other 31 sources previously reported as extended objects do not harbor a stellar source in our HST/ACS images. We also report on the detection of 16 red, elongated sources. Their location at the edges of the field, far from the Trapezium cluster core (gsim10'), suggests that these are probably background galaxies observed through low-extinction regions of the Orion Molecular Cloud (OMC-1). Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is

  15. Optical Metrology for the Filter Set for the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS)

    Science.gov (United States)

    Leviton, Douglas B.; Boucarut, Rene A.; Content, David A.; Keski-Kuha, Ritva A.; Krebs, Carolyn A.; Miner, Linda A.; Norton, Todd A.; Mehalick, Kimberly; Petrone, Peter; Bush, Frank D.; Puc, Bernard; Standley, Clive; Tsvetanov, Zlatan; Kral, Catherine

    1998-01-01

    The Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) will employ a wide variety of spectral filtration components including narrow band, medium band, wide band, and far ultraviolet (FUV) long pass filters, spatially- variable filters (ramp filters), VIS/IR polarizers, NUV polarizers, FUV prisms, and a grism. These components are spread across ACS's Wide Field, High Resolution, and Solar Blind channels which provide diffraction-limited imaging of astronomical targets using aberration-correcting optics which remove most aberrations from HST's Optical Telescope Assembly (OTA). In order for ACS to be truly advanced, these filters must push the state-of-the-art in performance in a number of key areas at the same time. Important requirements which these filters must meet include outstanding transmitted wavefront, high transmittance, uniform transmittance across each filter, spectrally structure-free bandpasses, exceptionally high out of band rejection, and a high degree of parfocality. These constitute a very stringent set of requirements indeed, especially for filters which are up to 90 mm in diameter. The development of optical metrology stations used to demonstrate that each ACS filter will meet its design specifications is discussed. Of particular note are specially-designed spectral transmissometers and interferometers.

  16. O-6 Optical Property Degradation of the Hubble Space Telescope's Wide Field Camera-2 Pick Off Mirror

    Science.gov (United States)

    McNamara, Karen M.; Hughes, D. W.; Lauer, H. V.; Burkett, P. J.; Reed, B. B.

    2011-01-01

    Degradation in the performance of optical components can be greatly affected by exposure to the space environment. Many factors can contribute to such degradation including surface contaminants; outgassing; vacuum, UV, and atomic oxygen exposure; temperature cycling; or combinations of parameters. In-situ observations give important clues to degradation processes, but there are relatively few opportunities to correlate those observations with post-flight ground analyses. The return of instruments from the Hubble Space Telescope (HST) after its final servicing mission in May 2009 provided such an opportunity. Among the instruments returned from HST was the Wide-Field Planetary Camera-2 (WFPC-2), which had been exposed to the space environment for 16 years. This work focuses on the identifying the sources of degradation in the performance of the Pick-off mirror (POM) from WFPC-2. Techniques including surface reflectivity measurements, spectroscopic ellipsometry, FTIR (and ATR-FTIR) analyses, SEM/EDS, X-ray photoelectron spectroscopy (XPS) with and without ion milling, and wet and dry physical surface sampling were performed. Destructive and contact analyses took place only after completion of the non-destructive measurements. Spectroscopic ellipsometry was then repeated to determine the extent of contaminant removal by the destructive techniques, providing insight into the nature and extent of polymerization of the contaminant layer.

  17. Evaluation of COSTAR mass handling characteristics in an environment. A simulation of the Hubble Space Telescope service mission

    Science.gov (United States)

    Rajulu, Sudhakar L.; Klute, Glenn K.; Fletcher, Lauren

    1994-01-01

    The STS-61 Shuttle mission, which took place in December 1993, was solely aimed at servicing the Hubble Space Telescope (HST). Successful completion of this mission was critical to NASA since it was necessary to rectify a flaw in the HST mirror. In addition, NASA had never scheduled a mission with such a high quantity of complex extravehicular activity. To meet the challenge of this mission, the STS-61 crew trained extensively in the Weightless Environment Test Facility at the Johnson Space Center and in the Neutral Buoyancy Simulator at the Marshall Space Flight Center. However, it was suspected that neutral buoyancy training might induce negative training by virtue of the viscous damping effect present in water. The mockups built for this training also did not have the mass properties of the actual orbital replacement units (ORUs). It was felt that the crew should be further trained on mockups with similar mass characteristics. A comprehensive study was designed to address these issues. The study was quantitative, and instrumentation was set up to measure and quantify the forces and moments experienced during ORU mass handling and remote manipulator system run conditions.

  18. Detection of dark energy near the Local Group with the Hubble Space Telescope

    CERN Document Server

    Chernin, A D; Teerikorpi, P; Valtonen, M J; Byrd, G G; Efremov, Yu N; Dolgachev, V P; Domozhilova, L M; Makarov, D I; Baryshev, Yu V

    2007-01-01

    We report the detection of dark energy near the Milky Way made with precision observations of the local Hubble flow of expansion. We estimate the local density of dark energy and find that it is near, if not exactly equal to, the global dark energy density. The result is independent of, compatible with, and complementary to the horizon-scale observations in which dark energy was first discovered. Together with the cosmological concordance data, our result forms direct observational evidence for the Einstein antigravity as a universal phenomenon -- in the same sense as the Newtonian universal gravity.

  19. Investigating the Core Morphology-Seyfert Class relationship with Hubble Space Telescope Archival Images of local Seyfert galaxies

    CERN Document Server

    Rutkowski, M J; Kim, Hwihyun; Tamura, Kazuyuki; Windhorst, R A

    2013-01-01

    The Unified Model of Active Galactic Nuclei (AGN) has provided a successful explanation for the observed diversity of AGN in the local Universe. However, recent analysis of multi-wavelength spectral and image data suggests that the Unified Model is only a partial theory of AGN, and may need to be augmented to remain consistent with all observations. Recent studies using high spatial resolution ground- and space-based observations of local AGN show that Seyfert class and the "core" (r<~1 kpc) host-galaxy morphology are correlated. Currently, this relationship has only been established qualitatively, by visual inspection of the core morphologies of low redshift (z<0.035) Seyfert host galaxies (Malkan et al. 1998). We re-establish this empirical relationship in Hubble Space Telescope (HST) optical imaging by visual inspection of a catalog of 85 local (D<63 Mpc) Seyfert galaxies. We also attempt to re-establish the core morphology-Seyfert class relationship using an automated, non-parametric technique th...

  20. A New Determination of the High Redshift Type Ia Supernova Rates with the Hubble Space Telescope Advanced Camera for Surveys

    CERN Document Server

    Kuznetsova, N; Connolly, B; Kim, A G; Pain, R; Roe, N A; Aldering, G; Amanullah, R; Dawson, K; Doi, M; Fadeev, V; Fruchter, A S; Gibbons, R; Goldhaber, G; Goobar, A; Gude, A; Knop, R A; Kowalski, M; Lidman, C; Morokuma, T; Meyers, J; Perlmutter, S; Rubin, D; Schlegel, D J; Spadafora, A L; Stanishev, V; Strovink, M; Suzuki, N; Wang, L; Yasuda, N

    2007-01-01

    We present a new measurement of the volumetric rate of Type Ia supernova up to a redshift of 1.7, using the Hubble Space Telescope (HST) GOODS data combined with an additional HST dataset covering the North GOODS field collected in 2004. We employ a novel technique that does not require spectroscopic data for identifying Type Ia supernovae (although spectroscopic measurements of redshifts are used for over half the sample); instead we employ a Bayesian approach using only photometric data to calculate the probability that an object is a Type Ia supernova. This Bayesian technique can easily be modified to incorporate improved priors on supernova properties, and it is well-suited for future high-statistics supernovae searches in which spectroscopic follow up of all candidates will be impractical. Here, the method is validated on both ground- and space-based supernova data having some spectroscopic follow up. We combine our volumetric rate measurements with low redshift supernova data, and fit to a number of pos...

  1. Improved Hubble Space Telescope Proper Motions for Tycho-G and Other Stars in the Remnant of Tycho's Supernova 1572

    CERN Document Server

    Bedin, L R; Hernandez, J I Gonzalez; Canal, R; Filippenko, A V; Mendez, J; .,

    2013-01-01

    With archival and new Hubble Space Telescope observations we have refined the space-velocity measurements of the stars in the central region of the remnant of Tycho's supernova (SN) 1572, one of the historical Galactic Type Ia supernova remnants (SNRs). We derived a proper motion for Tycho-G of (mu_RA_cos_dec;mu_dec)=(-2.63;-3.98)+/-(0.06;0.04)[formal errors]+/-(0.18;0.10)[expected errors] mas/yr. We also reconstruct the binary orbit that Tycho-G should have followed if it were the surviving companion of SN 1572. We redetermine the Ni abundance of this star and compare it with new abundance data from stars of the Galactic disk, finding that [Ni/Fe] is about 1.7 sigma above the Galactic trend. From the high velocity (v_b = -50+/-14 km/s) of Tycho-G perpendicular to the Galactic plane, its metallicity, and its Ni excess, we find the probability of its being a chance interloper to be P < 0.00037 at most. The projected rotational velocity of the star should be below current observational limits. The projected ...

  2. A New Determination of the High Redshift Type Ia Supernova Rateswith the Hubble Space Telescope Advanced Camera for Surveys

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsova, N.; Barbary, K.; Connolly, B.; Kim, A.G.; Pain, R.; Roe, N.A.; Aldering, G.; Amanullah, R.; Dawson, K.; Doi, M.; Fadeyev, V.; Fruchter, A.S.; Gibbons, R.; Goldhaber, G.; Goober, A.; Gude, A.; Knop,R.A.; Kowalski, M.; Lidman, C.; Morokuma, T.; Meyers, J.; Perlmutter, S.; Rubin, D.; Schlegel, D.J.; Spadafora, A.L.; Stanishev, V.; Strovink, M.; Suzuki, N.; Wang, L.; Yasuda, N.

    2007-10-01

    We present a new measurement of the volumetric rate of Type Ia supernova up to a redshift of 1.7, using the Hubble Space Telescope (HST) GOODS data combined with an additional HST dataset covering the North GOODS field collected in 2004. We employ a novel technique that does not require spectroscopic data for identifying Type Ia supernovae (although spectroscopic measurements of redshifts are used for over half the sample); instead we employ a Bayesian approach using only photometric data to calculate the probability that an object is a Type Ia supernova. This Bayesian technique can easily be modified to incorporate improved priors on supernova properties, and it is well-suited for future high-statistics supernovae searches in which spectroscopic follow up of all candidates will be impractical. Here, the method is validated on both ground- and space-based supernova data having some spectroscopic follow up. We combine our volumetric rate measurements with low redshift supernova data, and fit to a number of possible models for the evolution of the Type Ia supernova rate as a function of redshift. The data do not distinguish between a flat rate at redshift > 0.5 and a previously proposed model, in which the Type Ia rate peaks at redshift {approx} 1 due to a significant delay from star-formation to the supernova explosion. Except for the highest redshifts, where the signal to noise ratio is generally too low to apply this technique, this approach yields smaller or comparable uncertainties than previous work.

  3. A Hubble space telescope search for a sub-Earth-sized exoplanet in the GJ 436 system

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, Kevin B. [NASA Sagan Fellow. (United States); Bean, Jacob L.; Fabrycky, Daniel; Kreidberg, Laura, E-mail: kbs@uchicago.edu [Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)

    2014-11-20

    The detection of small planets orbiting nearby stars is an important step toward the identification of Earth twins. In previous work using the Spitzer Space Telescope, we found evidence to support at least one sub-Earth-sized exoplanet orbiting the nearby mid-M dwarf star GJ 436. As a follow up, here we used the Hubble Space Telescope (HST) to investigate the existence of one of these candidate planets, UCF-1.01, by searching for two transit signals as it passed in front of its host star. Interpretation of the data hinges critically on correctly modeling and removing the Wide Field Camera 3 (WFC3) instrument systematics from the light curves. Building on previous HST work, we demonstrate that WFC3 analyses need to explore the use of a quadratic function to fit a visit-long time-dependent systematic. This is important for establishing absolute transit and eclipse depths in the white light curves of all transiting systems. The work presented here exemplifies this point by putatively detecting the primary transit of UCF-1.01 with the use of a linear trend. However, using a quadratic trend, we achieve a better fit to the white light curves and a reduced transit depth that is inconsistent with previous Spitzer measurements. Furthermore, quadratic trends with or without a transit model component produce comparable fits to the available data. Using extant WFC3 transit light curves for GJ 436b, we further validate the quadratic model component by achieving photon-limited model fit residuals and consistent transit depths over multiple epochs. We conclude that, when we fit for a quadratic trend, our new data contradict the prediction of a sub-Earth-sized planet orbiting GJ 436 with the size, period, and ephemeris posited from the Spitzer data by a margin of 3.1σ.

  4. Analysis of Hubble Space Telescope Fine Guidance Sensor Data in TRANS Mode: An Overview

    Directory of Open Access Journals (Sweden)

    Elliott P. Horch

    2006-01-01

    Full Text Available El Sensor para el Guiado Fino del Telescopio Espacial Hubble ha sido un instrumento muy productivo en el campo de las estrellas binarias. En este trabajo el autor describe el instrumento brevemente y discute el formato de datos de las observaciones en modo TRANS. Este modo es empleado para la realización de observaciones conducentes a la obtención de la astrometría relativa de estrellas binarias con baja separación angular. Los procedimientos de análisis de datos típicamente usados son discutidos aquí y se introduce además una nueva técnica para la determinación de los colores de las componentes de estrellas binarias, basada en el análisis de Fourier.

  5. Near-infrared Hubble Space Telescope polarimetry of a complete sample of narrow-line radio galaxies

    CERN Document Server

    Ramírez, E A; Axon, D; Batcheldor, D; Packham, C; Lopez-Rodriguez, E; Sparks, W; Young, S

    2014-01-01

    We present an analysis of 2.05 $\\mu$m Hubble Space Telescope (HST) polarimetric data for a sample of 13 nearby Fanaroff-Riley type II (FRII) 3CR radio sources ($0.03

  6. The Star Formation Histories of Local Group Dwarf Galaxies I. Hubble Space Telescope / Wide Field Planetary Camera 2 Observations

    CERN Document Server

    Weisz, Daniel R; Skillman, Evan D; Holtzman, Jon; Gilbert, Karoline M; Dalcanton, Julianne J; Williams, Benjamin F

    2014-01-01

    We present uniformly measured star formation histories (SFHs) of 40 Local Group dwarf galaxies based on color-magnitude diagram (CMD) analysis from archival Hubble Space Telescope imaging. We demonstrate that accurate SFHs can be recovered from CMDs that do not reach the oldest main sequence turn-off (MSTO), but emphasize that the oldest MSTO is critical for precisely constraining the earliest epochs of star formation. We find that: (1) the average lifetime SFHs of dwarf spheroidals (dSphs) can be approximated by an exponentially declining SFH with $\\tau$ $\\sim$ 5 Gyr; (2) lower luminosity dSphs are less likely to have extended SFHs than more luminous dSphs; (3) the average SFHs of dwarf irregulars (dIrrs), transition dwarfs (dTrans), and dwarf ellipticals (dEs) can be approximated by the combination of an exponentially declining SFH ($\\tau$ $\\sim$ 3-4 Gyr) for lookback ages $>$ 10-12 Gyr ago and a constant SFH thereafter; (4) the observed fraction of stellar mass formed prior to z=2 ranges considerably (80\\%...

  7. Hubble Space Telescope and Ground-Based Observations of the Type Iax Supernovae SN 2005hk and SN 2008A

    CERN Document Server

    McCully, Curtis; Foley, Ryan J; Chornock, Ryan; Holtzman, Jon A; Balam, David D; Branch, David; Filippenko, Alexei V; Frieman, Joshua; Fynbo, Johan; Galbany, Lluis; Ganeshalingam, Mohan; Garnavich, Peter M; Graham, Melissa L; Hsiao, Eric Y; Leloudas, Giorgos; Leonard, Douglas C; Li, Weidong; Riess, Adam G; Sako, Masao; Schneider, Donald P; Silverman, Jeffrey M; Sollerman, Jesper; Steele, Thea N; Thomas, Rollin C; Wheeler, J Craig; Zheng, Chen

    2013-01-01

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). These objects are peculiar cousins of normal Type Ia SNe, with SN 2002cx as the prototype. Here we focus on late-time observations, where these objects deviate most dramatically from normal SNe Ia. Instead of the dominant nebular emission lines that are observed in normal SNe Ia at late phases (and indeed, in SNe of all other types), spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with n_e >~ 10^9 cm^-3. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected "infrared catastrophe," a generic feature of SN Ia models. However, our HST photom...

  8. Three Axis Control of the Hubble Space Telescope Using Two Reaction Wheels and Magnetic Torquer Bars for Science Observations

    Science.gov (United States)

    Hur-Diaz, Sun; Wirzburger, John; Smith, Dan

    2008-01-01

    The Hubble Space Telescope (HST) is renowned for its superb pointing accuracy of less than 10 milli-arcseconds absolute pointing error. To accomplish this, the HST relies on its complement of four reaction wheel assemblies (RWAs) for attitude control and four magnetic torquer bars (MTBs) for momentum management. As with most satellites with reaction wheel control, the fourth RWA provides for fault tolerance to maintain three-axis pointing capability should a failure occur and a wheel is lost from operations. If an additional failure is encountered, the ability to maintain three-axis pointing is jeopardized. In order to prepare for this potential situation, HST Pointing Control Subsystem (PCS) Team developed a Two Reaction Wheel Science (TRS) control mode. This mode utilizes two RWAs and four magnetic torquer bars to achieve three-axis stabilization and pointing accuracy necessary for a continued science observing program. This paper presents the design of the TRS mode and operational considerations necessary to protect the spacecraft while allowing for a substantial science program.

  9. Near-IR Emission Spectrum of WASP-103b using Hubble Space Telescope/Wide Field Camera 3

    CERN Document Server

    Cartier, Kimberly M S; Zhao, Ming; Line, Michael; Ngo, Henry; Mawet, Dimitri; Stassun, Keivan G; Wright, Jason T; Kreidberg, Laura; Fortney, Jonathan; Knutson, Heather

    2016-01-01

    We present here our observations and analysis of the dayside emission spectrum of the hot Jupiter WASP-103b. We observed WASP-103b during secondary eclipse using two visits of the Hubble Space Telescope with the G141 grism on Wide Field Camera 3 in spatial scan mode. We generated secondary eclipse light curves of the planet in both blended white-light and spectrally binned wavechannels from 1.1-1.7 micron and corrected the light curves for flux contamination from a nearby companion star. We modeled the detector systematics and secondary eclipse spectrum using Gaussian process regression and found that the near-IR emission spectrum of WASP-103b is featureless across the observed near-IR region to down to a sensitivity of 175 ppm, and shows a shallow slope towards the red. The atmosphere has a single brightness temperature of T_B = 2890 K across this wavelength range. This region of the spectrum is indistinguishable from isothermal, but may not manifest from a physically isothermal system, i.e. pseudo-isotherma...

  10. Hubble Space Telescope Observations of the CfA Seyfert 2s The Fueling of Active Galactic Nuclei

    CERN Document Server

    Martini, P; Pogge, Richard W; Martini, Paul

    1999-01-01

    We present an investigation of possible fueling mechanisms operating in the inner kiloparsec of Seyfert galaxies. We analyze visible and near-infrared Hubble Space Telescope images of 24 Seyfert 2s from the CfA Redshift Survey sample. In particular, we are searching for the morphological signatures of dynamical processes reponsible for transporting gas from kiloparsec scales into the nucleus. The circumnuclear regions are very rich in gas and dust, often taking the form of nuclear spiral dust lanes on scales of a few hundred parsecs. While these nuclear spirals are found in 20 of our 24 Seyferts, we find only 5 nuclear bars among the entire sample, strongly reinforcing the conclusions of other investigators that nuclear bars are not the primary means of transporting this material into the nucleus. An estimate of the gas density in the nuclear spirals based on extinction measurements suggests that the nuclear spiral dust lanes are probably shocks in nuclear gas disks that are not strongly self-gravitating. Sin...

  11. Hubble space telescope and ground-based observations of the type Iax supernovae SN 2005hk and SN 2008A

    Energy Technology Data Exchange (ETDEWEB)

    McCully, Curtis; Jha, Saurabh W. [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Foley, Ryan J. [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Chornock, Ryan [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Holtzman, Jon A. [Department of Astronomy, MSC 4500, New Mexico State University, P.O. Box 30001, Las Cruces, NM 88003 (United States); Balam, David D. [Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Branch, David [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States); Filippenko, Alexei V.; Ganeshalingam, Mohan; Li, Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Frieman, Joshua [Kavli Institute for Cosmological Physics and Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Fynbo, Johan; Leloudas, Giorgos [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen Ø (Denmark); Galbany, Lluis [Institut de Física d' Altes Energies, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona) (Spain); Garnavich, Peter M. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Graham, Melissa L. [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Hsiao, Eric Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Leonard, Douglas C., E-mail: cmccully@physics.rutgers.edu [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); and others

    2014-05-10

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). Here we focus on late-time observations, where these objects deviate most dramatically from all other SN types. Instead of the dominant nebular emission lines that are observed in other SNe at late phases, spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with n{sub e} ≳ 10{sup 9} cm{sup –3}. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected 'infrared catastrophe', a generic feature of SN Ia models. However, our HST photometry of SN 2008A does not match the predictions of an infrared catastrophe. Moreover, our HST observations rule out a 'complete deflagration' that fully disrupts the white dwarf for these peculiar SNe, showing no evidence for unburned material at late times. Deflagration explosion models that leave behind a bound remnant can match some of the observed properties of SNe Iax, but no published model is consistent with all of our observations of SNe 2005hk and 2008A.

  12. Constraints on the binary properties of mid- to late T dwarfs from Hubble space telescope WFC3 observations

    Energy Technology Data Exchange (ETDEWEB)

    Aberasturi, M.; Solano, E. [Centro de Astrobiología (INTA-CSIC), Departamento de Astrofísica, P.O. Box 78, E-28691 Villanueva de la Cañada, Madrid (Spain); Burgasser, A. J. [Center for Astrophysics and Space Science, University of California San Diego, La Jolla, CA 92093 (United States); Mora, A. [ESA–ESAC, Gaia SOC. P.O. Box 78, E-28691 Villanueva de la Cañada, Madrid (Spain); Martín, E. L. [Centro de Astrobiología (INTA-CSIC), Departamento de Astrofísica. Carretera de Ajalvir km 4, E-28550 Torrejín de Ardoz, Madrid (Spain); Reid, I. N. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Looper, D. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

    2014-12-01

    We used Hubble Space Telescope/Wide Field Camera 3 (WFC3) observations of a sample of 26 nearby (≤20 pc) mid- to late T dwarfs to search for cooler companions and measure the multiplicity statistics of brown dwarfs (BDs). Tightly separated companions were searched for using a double point-spread-function-fitting algorithm. We also compared our detection limits based on simulations to other prior T5+ BD binary programs. No new wide or tight companions were identified, which is consistent with the number of known T5+ binary systems and the resolution limits of WFC3. We use our results to add new constraints to the binary fraction (BF) of T-type BDs. Modeling selection effects and adopting previously derived separation and mass ratio distributions, we find an upper limit total BF of <16% and <25% assuming power law and flat mass ratio distributions, respectively, which are consistent with previous results. We also characterize a handful of targets around the L/T transition.

  13. Hubble Space Telescope Observations of SV Cam: I. The Importance of Unresolved Starspot Distributions in Lightcurve Fitting

    CERN Document Server

    Jeffers, S V; Cameron, A C; Donati, J F

    2006-01-01

    We have used maximum entropy eclipse mapping to recover images of the visual surface brightness distribution of the primary component of the RS CVn eclipsing binary SV Cam, using high-precision photometry data obtained during three primary eclipses with STIS aboard the Hubble Space Telescope. These were augmented by contemporaneous ground-based photometry secured around the rest of the orbit. The goal of these observations was to determine the filling factor and size distribution of starspots too small to be resolved by Doppler imaging. The information content of the final image and the fit to the data were optimised with respect to various system parameters using the chi^2 landscape method, using an eclipse mapping code that solves for large-scale spot coverage. It is only with the unprecedented photometric precision of the HST data (0.00015 mag) that it is possible to see strong discontinuities at the four contact points in the residuals of the fit to the lightcurve. These features can only be removed from ...

  14. Design and Specification of Optical Bandpass Filters for Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS)

    Science.gov (United States)

    Leviton, Douglas B.; Tsevetanov, Zlatan; Woodruff, Bob; Mooney, Thomas A.

    1998-01-01

    Advanced optical bandpass filters for the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) have been developed on a filter-by-filter basis through detailed studies which take into account the instrument's science goals, available optical filter fabrication technology, and developments in ACS's charge-coupled-device (CCD) detector technology. These filters include a subset of filters for the Sloan Digital Sky Survey (SDSS) which are optimized for astronomical photometry using today's charge-coupled-devices (CCD's). In order for ACS to be truly advanced, these filters must push the state-of-the-art in performance in a number of key areas at the same time. Important requirements for these filters include outstanding transmitted wavefront, high transmittance, uniform transmittance across each filter, spectrally structure-free bandpasses, exceptionally high out of band rejection, a high degree of parfocality, and immunity to environmental degradation. These constitute a very stringent set of requirements indeed, especially for filters which are up to 90 mm in diameter. The highly successful paradigm in which final specifications for flight filters were derived through interaction amongst the ACS Science Team, the instrument designer, the lead optical engineer, and the filter designer and vendor is described. Examples of iterative design trade studies carried out in the context of science needs and budgetary and schedule constraints are presented. An overview of the final design specifications for the ACS bandpass and ramp filters is also presented.

  15. Hubble Space Telescope and Ground-Based Observations of the Type Iax Supernovae SN 2005hk and SN 2008A

    Energy Technology Data Exchange (ETDEWEB)

    McCully, Curtis; Jha, Saurabh W.; Foley, Ryan J.; Chornock, Ryan; Holtzman, Jon A.; Balam, David D.; Branch, David; Filippenko, Alexei V.; Frieman, Joshua; Fynbo, Johan; Galbany, Lluis; Ganeshalingam, Mohan; Garnavich, Peter M.; Graham, Melissa L.; Hsiao, Eric Y.; Leloudas, Giorgos; Leonard, Douglas C.; Li, Weidong; Riess, Adam G.; Sako, Masao; Schneider, Donald P.; Silverman, Jeffrey M.; Sollerman, Jesper; Steele, Thea N.; Thomas, Rollin C.; Wheeler, J. Craig; Zheng, Chen

    2014-04-24

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). Here we focus on late-time observations, where these objects deviate most dramatically from all other SN types. Instead of the dominant nebular emission lines that are observed in other SNe at late phases, spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with ne109 cm–3. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected "infrared catastrophe," a generic feature of SN Ia models. However, our HST photometry of SN 2008A does not match the predictions of an infrared catastrophe. Moreover, our HST observations rule out a "complete deflagration" that fully disrupts the white dwarf for these peculiar SNe, showing no evidence for unburned material at late times. Deflagration explosion models that leave behind a bound remnant can match some of the observed properties of SNe Iax, but no published model is consistent with all of our observations of SNe 2005hk and 2008A.

  16. Hubble Space Telescope Proper Motions of Individual Stars in Stellar Streams: Orphan, Sagittarius, Lethe, and the New "Parallel’ Stream"

    Science.gov (United States)

    Sohn, Sangmo Tony; van der Marel, Roeland P.; Kallivayalil, Nitya; Majewski, Steven R.; Besla, Gurtina; Carlin, Jeffrey L.; Law, David R.; Siegel, Michael H.; Anderson, Jay

    2016-12-01

    We present a multi-epoch Hubble Space Telescope (HST) study of stellar proper motions (PMs) for four fields along the Orphan Stream. We determine absolute PMs of several individual stars per target field using established techniques that utilize distant background galaxies to define a stationary reference frame. Five Orphan Stream stars are identified in one of the four fields based on combined color-magnitude and PM information. The average PM is consistent with the existing model of the Orphan Stream by Newberg et al. In addition to the Orphan Stream stars, we detect stars that likely belong to other stellar streams. To identify which stellar streams these stars belong to, we examine the 2d bulk motion of each group of stars on the sky by subtracting the PM contribution of the solar motion (which is a function of position on the sky and distance) from the observed PMs, and comparing the vector of net motion with the spatial extent of known stellar streams. By doing this, we identify candidate stars in the Sagittarius and Lethe streams, and a newly found stellar stream at a distance of ˜17 kpc, which we tentatively name the “Parallel Stream.” Together with our Sagittarius stream study, this work demonstrates that even in the Gaia era, HST will continue to be advantageous in measuring PMs of old stellar populations on a star-by-star basis, especially for distances beyond ˜10 kpc.

  17. Hubble Space Telescope Proper Motions along the Sagittarius Stream: I. Observations and Results for Stars in Four Fields

    CERN Document Server

    Sohn, Sangmo Tony; Carlin, Jeffrey L; Majewski, Steven R; Kallivayalil, Nitya; Law, David R; Anderson, Jay; Siegel, Michael H

    2014-01-01

    We present a Hubble Space Telescope (HST) study of stellar proper motions (PMs) for four fields spanning 200 degrees along the Sagittarius (Sgr) stream: one field in the trailing arm, one field near the Sgr dSph tidal radius, and two fields in the leading arm. From data with 6-9 year time baselines, we determine absolute PMs of dozens of individual stars per field, using established techniques that use distant background galaxies to define a stationary reference frame. Stream stars are identified based on combined color-magnitude diagram (CMD) and PM information. The results are broadly consistent with the few existing PM measurements for the Sgr dwarf spheroidal galaxy (dSph) and the trailing arm. However, our new results provide the highest PM accuracy for the stream to date, the first PM measurements for the leading arm, and the first PM measurements for individual stream stars [We also serendipitously determine the PM of the globular cluster NGC 6652 to be ($\\mu_{\\rm W}$, $\\mu_{\\rm N}$) = (5.66 $\\pm$ 0.07...

  18. The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. IX. The Atlas of Multiple Stellar Populations

    CERN Document Server

    Milone, A P; Renzini, A; Marino, A F; Bedin, L R; Vesperini, E; D'Antona, F; Nardiello, D; Anderson, J; King, I R; Yong, D; Bellini, A; Aparicio, A; Barbuy, B; Brown, T M; Cassisi, S; Ortolani, S; Salaris, M; Sarajedini, A; van der Marel, R P

    2016-01-01

    We use high-precision photometry of red-giant-branch (RGB) stars in 57 Galactic globular clusters (GCs), mostly from the `Hubble Space Telescope (HST) UV Legacy Survey of Galactic globular clusters', to identify and characterize their multiple stellar populations. For each cluster the pseudo two-color diagram (or `chromosome map') is presented, built with a suitable combination of stellar magnitudes in the F275W, F336W, F438W and F814W filters that maximizes the separation between multiple populations. In the chromosome map of most GCs (Type I clusters), stars separate in two distinct groups that we identify with the first (1G) and the second generation (2G). This identification is further supported by noticing that 1G stars have primordial (oxygen-rich, sodium-poor) chemical composition, whereas 2G stars are enhanced in sodium and depleted in oxygen. This 1G-2G separation is not possible for a few GCs where the two sequences have apparently merged into an extended, continuous sequence. In some GCs (Type II c...

  19. Hubble Space Telescope Faint Object Camera Spectroscopy of the Narrow-Line Region of NGC 4151. I. Gas Kinematics

    CERN Document Server

    Winge, C; Macchetto, F D; Capetti, A; Marconi, A; Winge, Claudia; Axon, David J.

    1999-01-01

    We present the results from a detailed kinematic analysis of both ground-based, and Hubble Space Telescope/Faint Object Camera long-slit spectroscopy at sub-arcsec spatial resolution, of the narrow-line region of NGC 4151. In agreement with previous work, the extended emission gas (R > 4") is found to be in normal rotation in the galactic plane, a behaviour that we were able to trace even across the nuclear region, where the gas is strongly disturbed by the interaction with the radio jet, and connects smoothly with the large scale rotation defined by the neutral gas emission. The HST data, at 0.029" spatial resolution, allow us for the first time to truly isolate the kinematic behaviour of the individual clouds in the inner narrow-line region. We find that, underlying the perturbations introduced by the radio ejecta, the general velocity field can still be well represented by planar rotation down to a radius of ~ 0.5" (30 pc), distance at which the rotation curve has its turnover. The most striking result tha...

  20. Hubble Space Telescope NICMOS Observations of T Dwarfs: Brown Dwarf Multiplicity and New Probes of the L/T Transition

    CERN Document Server

    Burgasser, A J; Cruz, K L; Reid, I N; Leggett, S K; Liebert, J; Burrows, A; Brown, M E; Burgasser, Adam J.; Cruz, Kelle L.; Leggett, Sandy K.; Liebert, James; Burrows, Adam; Brown, Michael E.

    2006-01-01

    We present the results of a Hubble Space Telescope NICMOS imaging survey of 22 T-type field brown dwarfs. Five are resolved as binary systems with angular separations of 0"05-0"35, and companionship is established on the basis of component F110W-F170M colors (indicative of CH4 absorption) and low probabilities of background contamination. Prior ground-based observations show 2MASS 1553+1532AB to be a common proper motion binary. The properties of these systems - low multiplicity fraction (11[+7][-3]% resolved, as corrected for sample selection baises), close projected separations (a = 1.8-5.0 AU) and near-unity mass ratios - are consistent with previous results for field brown dwarf binaries. Three of the binaries have components that span the poorly-understood transition between L dwarfs and T dwarfs. Spectral decomposition analysis of one of these, SDSS 1021-0304AB, reveals a peculiar flux reversal between its components, as its T5 secondary is ~30% brighter at 1.05 and 1.27 micron than its T1 primary. This...

  1. DEEP CHANDRA MONITORING OBSERVATIONS OF NGC 4649. II. WIDE-FIELD HUBBLE SPACE TELESCOPE IMAGING OF THE GLOBULAR CLUSTERS

    Energy Technology Data Exchange (ETDEWEB)

    Strader, Jay [Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan, MI 48824 (United States); Fabbiano, Giuseppina; Luo, Bin; Kim, Dong-Woo; Fragos, Tassos [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Brodie, Jean P. [UCO/Lick Observatory, 1156 High Street, Santa Cruz, CA 95064 (United States); Gallagher, John S. [Department of Astronomy, University of Wisconsin, Madison, WI 53706-1582 (United States); Kalogera, Vassiliki [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); King, Andrew [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Zezas, Andreas, E-mail: strader@pa.msu.edu [Physics Department, University of Crete, P.O. Box 2208, GR-710 03, Heraklion, Crete (Greece)

    2012-11-20

    We present g and z photometry and size estimates for globular clusters (GCs) in the massive Virgo elliptical NGC 4649 (M60) using a five-pointing Hubble Space Telescope/Advanced Camera for Surveys mosaic. The metal-poor GCs show a monotonic negative metallicity gradient of -0.43 {+-} 0.10 dex per dex in radius over the full radial range of the data, out to {approx}24 kpc. There is evidence for substantial color substructure among the metal-rich GCs. The metal-poor GCs have typical sizes {approx}0.4 pc larger than the metal-rich GCs out to large galactocentric distances ({approx}> 20 kpc), favoring an intrinsic explanation for the size difference rather than projection effects. There is no clear relation between half-light radius and galactocentric distance beyond {approx}15 kpc, suggesting that the sizes of GCs are not generically set by tidal limitation. Finally, we identify {approx}20 candidate ultracompact dwarfs that extend down to surprisingly faint absolute magnitudes (M{sub z} {approx} -8.5), and may bridge the gap between this class and 'extended clusters' in the Local Group. Three of the brighter candidates have published radial velocities and can be confirmed as bona fide ultracompact dwarfs; follow-up spectroscopy will determine the nature of the remainder of the candidates.

  2. The Star-Forming Region NGC 346 in the Small Magellanic Cloud with Hubble Space Telescope ACS Observations I. Photometry

    CERN Document Server

    Gouliermis, D A; Brandne, W; Henning, T; Henning, Th.

    2006-01-01

    We present a photometric study of the star-forming region NGC 346 and its surrounding field in the Small Magellanic Cloud, using data taken with the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST). The data set contains both short and long exposures for increased dynamic range, and photometry was performed using the ACS module of the stellar photometry package DOLPHOT. We detected almost 100,000 stars over a magnitude range of V ~ 11 to V ~ 28 mag, including all stellar types from the most massive young stars to faint lower main sequence and pre-main sequence stars. We find that this region, which is characterized by a plethora of stellar systems and interesting objects, is an outstanding example of mixed stellar populations. We take into account different features of the color-magnitude diagram of all the detected stars to distinguish the two dominant stellar systems: The stellar association NGC 346 and the old spherical star cluster BS 90. These observations provide a complete st...

  3. Imaging of four planetary nebulae in the Magellanic Clouds using the Hubble Space Telescope Faint Object Camera

    Science.gov (United States)

    Blades, J. C.; Barlow, M. J.; Albrecht, R.; Barbieri, C.; Boksenberg, A.; Crane, P.; Deharveng, J. M.; Disney, M. J.; Jakobsen, P.; Kamperman, T. M.

    1992-01-01

    Using the Faint Object Camera on-board the Hubble Space Telescope, we have obtained images of four planetary nebulae (PNe) in the Magellanic Clouds, namely N2 and N5 in the SMC and N66 and N201 in the LMC. Each nebula was imaged through two narrow-band filters isolating forbidden O III 5007 and H-beta, for a nominal exposure time of 1000 s in each filter. In forbidden O III, SMC N5 shows a circular ring structure, with a peak-to-peak diameter of 0.26 arcsec and a FWHM of 0.35 arcsec while SMC N2 shows an elliptical ring structure with a peak-to-peak diameter of 0.26 x 0.21. The expansion ages corresponding to the observed structures in SMC N2 and N5 are of the order of 3000 yr. LMC N201 is very compact, with a FWHM of 0.2 arcsec in H-beta. The Type I PN LMC N66 is a multipolar nebula, with the brightest part having an extent of about 2 arcsec and with fainter structures extending over 4 arcsec.

  4. The HST/WFC3 Quicklook Project: A User Interface to Hubble Space Telescope Wide Field Camera 3 Data

    Science.gov (United States)

    Bourque, Matthew; Bajaj, Varun; Bowers, Ariel; Dulude, Michael; Durbin, Meredith; Gosmeyer, Catherine; Gunning, Heather; Khandrika, Harish; Martlin, Catherine; Sunnquist, Ben; Viana, Alex

    2017-06-01

    The Hubble Space Telescope's Wide Field Camera 3 (WFC3) instrument, comprised of two detectors, UVIS (Ultraviolet-Visible) and IR (Infrared), has been acquiring ~ 50-100 images daily since its installation in 2009. The WFC3 Quicklook project provides a means for instrument analysts to store, calibrate, monitor, and interact with these data through the various Quicklook systems: (1) a ~ 175 TB filesystem, which stores the entire WFC3 archive on disk, (2) a MySQL database, which stores image header data, (3) a Python-based automation platform, which currently executes 22 unique calibration/monitoring scripts, (4) a Python-based code library, which provides system functionality such as logging, downloading tools, database connection objects, and filesystem management, and (5) a Python/Flask-based web interface to the Quicklook system. The Quicklook project has enabled large-scale WFC3 analyses and calibrations, such as the monitoring of the health and stability of the WFC3 instrument, the measurement of ~ 20 million WFC3/UVIS Point Spread Functions (PSFs), the creation of WFC3/IR persistence calibration products, and many others.

  5. Evolution of Cluster Ellipticals at 0.2 < z < 1.2 from Hubble Space Telescope Imaging

    CERN Document Server

    Schade, D J; López-Cruz, O; Schade, David; Lopez-Cruz, Omar

    1996-01-01

    Two-dimensional surface photometry derived from Hubble Space Telescope imaging is presented for a sample of 225 early-type galaxies (assumed to be cluster members) in the fields of 9 clusters at redshifts $0.17 < z < 1.21$. The 94 luminous ellipticals ($M_{AB}(B)<-20$; selected by morphology alone with no reference to color) form tight sequences in the size-luminosity plane. The position of these sequences shifts, on average, with redshift so that an object of a given size at z=0.55 is brighter by $\\Delta M(B)=-0.57 \\pm 0.13$ mag than its counterpart (measured with the same techniques) in nearby clusters. At z=0.9 the shift is $\\Delta M(B)=-0.96 \\pm 0.22$ mag. If the relation between size and luminosity is universal so that the local cluster galaxies represent the evolutionary endpoints of those at high redshift, and if the size-luminosity relation is not modified by dynamical processes then this population of galaxies has undergone significant luminosity evolution since z=1 consistent with expectati...

  6. Hubble Space Telescope Detection of the Double Pulsar System J0737-3039 in the Far-ultraviolet

    Science.gov (United States)

    Durant, Martin; Kargaltsev, Oleg; Pavlov, George G.

    2014-03-01

    We report on detection of the double pulsar system J0737-3039 in the far-UV with the Advanced Camera for Surveys/Solar-blind Channel detector aboard Hubble Space Telescope. We measured the energy flux F = (4.6 ± 1.0) × 10-17 erg cm-2 s-1 in the 1250-1550 Å band, which corresponds to the extinction-corrected luminosity L ≈ 1.5 × 1028 erg s-1 for the distance d = 1.1 kpc and a plausible reddening E(B - V) = 0.1. If the detected emission comes from the entire surface of one of the neutron stars with a 13 km radius, the surface blackbody temperature is in the range T ~= (2-5) × 105 K for a reasonable range of interstellar extinction. Such a temperature requires an internal heating mechanism to operate in old neutron stars, or, less likely, it might be explained by heating of the surface of the less energetic Pulsar B by the relativistic wind of Pulsar A. If the far-ultraviolet emission is non-thermal (e.g., produced in the magnetosphere of Pulsar A), its spectrum exhibits a break between the UV and X-rays.

  7. Constraints on the Progenitor System of the Type Ia Supernova 2014J from Pre-Explosion Hubble Space Telescope Imaging

    Science.gov (United States)

    Kelly, Patrick L.; Fox, Ori D.; Filippenko, Alexei V.; Cenko, S. Bradley; Prato, Lisa; Schaefer, Gail; Shen, Ken J.; Zheng, WeiKang; Graham, Melissa L.; Tucker, Brad E.

    2014-01-01

    We constrain the properties of the progenitor system of the highly reddened Type Ia supernova (SN Ia) 2014J in Messier 82 (M82; d (is) approx. 3.5 Mpc). We determine the supernova (SN) location using Keck-II K-band adaptive optics images, and we find no evidence for flux from a progenitor system in pre-explosion near-ultraviolet through near-infrared Hubble Space Telescope (HST) images. Our upper limits exclude systems having a bright red giant companion, including symbiotic novae with luminosities comparable to that of RS Ophiuchi. While the flux constraints are also inconsistent with predictions for comparatively cool He-donor systems (T (is) approximately 35,000 K), we cannot preclude a system similar to V445 Puppis. The progenitor constraints are robust across a wide range of RV and AV values, but significantly greater values than those inferred from the SN light curve and spectrum would yield proportionally brighter luminosity limits. The comparatively faint flux expected from a binary progenitor system consisting of white dwarf stars would not have been detected in the pre-explosion HST imaging. Infrared HST exposures yield more stringent constraints on the luminosities of very cool (T (is) less than 3000 K) companion stars than was possible in the case of SN Ia 2011fe.

  8. Hubble Space Telescope times-series photometry of the planetary transit of HD189733: no moon, no rings, starspots

    CERN Document Server

    Pont, F; Bouchy, F; Brown, T M; Charbonneau, D; Mayor, M; Queloz, D; Santos, N; Udry, S

    2007-01-01

    We monitored three transits of the giant gas planet around the nearby K dwarf HD 189733 with the ACS camera on the Hubble Space Telescope. The resulting very-high accuracy lightcurve (signal-to-noise ratio near 15000 on individual measurements, 35000 on 10-minute averages) allows a direct geometric measurement of the orbital inclination, radius ratio and scale of the system: i = 85.68 +- 0.04 R_{pl}/R_*=0.1572 +- 0.0004, a/R_*=8.92 +- 0.09. We derive improved values for the stellar and planetary radius, R_*=0.755 +- 0.011 R_{sun}, R_{pl}=1.154 +- 0.017 R_J, and the transit ephemerides, T_{tr}=2453931.12048 +- 0.00002 + n 2.218581 +- 0.000002. The HST data also reveal clear evidence of the planet occulting spots on the surface of the star. At least one large spot complex (> 80000 km) is required to explain the observed flux residuals and their colour evolution. This feature is compatible in amplitude and phase with the variability observed simultaneously from the ground. No evidence for satellites or rings aro...

  9. Hubble Space Telescope Proper Motions of Individual Stars in Stellar Streams: Orphan, Sagittarius, Lethe, and the New "Parallel" Stream

    CERN Document Server

    Sohn, Sangmo Tony; Kallivayalil, Nitya; Majewski, Steven R; Besla, Gurtina; Carlin, Jeffrey L; Law, David R; Siegel, Michael H; Anderson, Jay

    2016-01-01

    We present a multi-epoch Hubble Space Telescope (HST) study of stellar proper motions (PMs) for four fields along the Orphan Stream. We determine absolute PMs of several individual stars per target field using established techniques that utilize distant background galaxies to define a stationary reference frame. Five Orphan Stream stars are identified in one of the four fields based on combined color-magnitude and PM information. The average PM is consistent with the existing model of the Orphan stream by Newberg et al. In addition to the Orphan stream stars, we detect stars that likely belong to other stellar streams. To identify which stellar streams these stars belong to, we examine the 2-d bulk motion of each group of stars on the sky by subtracting the PM contribution of the solar motion (which is a function of position on the sky and distance) from the observed PMs, and comparing the vector of net motion with the spatial extent of known stellar streams. By doing this, we identify candidate stars in the ...

  10. Hubble Space Telescope Spectroscopic Evidence for a 1 X 10 9 Msun Black Hole in NGC 4594

    Science.gov (United States)

    Kormendy, John; Bender, Ralf; Ajhar, Edward A.; Dressler, Alan; Faber, S. M.; Gebhardt, Karl; Grillmair, Carl; Lauer, Tod R.; Richstone, Douglas; Tremaine, Scott

    1996-12-01

    The discovery by Kormendy of a M• ~= 109 Msolar massive dark object (MDO) in NGC 4594 is confirmed with higher resolution spectroscopy from the Canada-France-Hawaii Telescope (CFHT) and the Hubble Space Telescope (HST). CFHT measurements with the Subarcsecond Imaging Spectrograph improve the resolution from sigma * = 0."40 to 0."27 Gaussian dispersion radius of the point-spread function (PSF). The apparent central velocity dispersion rises from sigma = 250 +/- 7 km s-1 to sigma = 286 +/- 7 km s-1. As observed with the COSTAR-corrected HST, the Faint Object Spectrograph, and a 0."21 aperture, sigma = 321 +/- 7 km s-1 is still higher, and the central rotation curve is very steep. The highest-M• published dynamical model fits the new observations reasonably well when "observed" at HST resolution. The spatial resolution has now improved by a factor of ~5 since the discovery measurements, and the case for a black hole (BH) has strengthened correspondingly. We confirm that NGC 4594 has a Seyfert spectrum; H alpha is ~5200 km s-1 wide at zero intensity. However, gas velocities are lower than the circular velocities implied by the stars, so they cannot be used to test the BH case in NGC 4594. The gas may be in a ring, or it may be associated with patchy dust. HST images with the Wide Field and Planetary Camera 2 show dust at some aperture positions. NGC 4594 appears to have a bright point nucleus. However, the central absorption-line strengths are low, consistent with dilution by enough nonthermal light to explain the "nucleus." There is no evidence for a distinct nuclear star cluster. NGC 4594 is similar to M87, which also has a nonthermal nuclear source, and not to M31 and NGC 3115, which have quiescent BHs and nuclear star clusters.

  11. A Remarkably Luminous Galaxy at z=11.1 Measured with Hubble Space Telescope Grism Spectroscopy

    CERN Document Server

    Oesch, P A; van Dokkum, P G; Illingworth, G D; Bouwens, R J; Labbe, I; Franx, M; Momcheva, I; Ashby, M L N; Fazio, G G; Gonzalez, V; Holden, B; Magee, D; Skelton, R E; Smit, R; Spitler, L R; Trenti, M; Willner, S P

    2016-01-01

    We present Hubble WFC3/IR slitless grism spectra of a remarkably bright $z\\gtrsim10$ galaxy candidate, GN-z11, identified initially from CANDELS/GOODS-N imaging data. A significant spectroscopic continuum break is detected at $\\lambda=1.47\\pm0.01~\\mu$m. The new grism data, combined with the photometric data, rule out all plausible lower redshift solutions for this source. The only viable solution is that this continuum break is the Ly$\\alpha$ break redshifted to ${z_\\mathrm{grism}=11.09^{+0.08}_{-0.12}}$, just $\\sim$400 Myr after the Big Bang. This observation extends the current spectroscopic frontier by 150 Myr to well before the Planck (instantaneous) cosmic reionization peak at z~8.8, demonstrating that galaxy build-up was well underway early in the reionization epoch at z>10. GN-z11 is remarkably and unexpectedly luminous for a galaxy at such an early time: its UV luminosity is 3x larger than L* measured at z~6-8. The Spitzer IRAC detections up to 4.5 $\\mu$m of this galaxy are consistent with a stellar m...

  12. Modular assembled space telescope

    Science.gov (United States)

    Feinberg, Lee D.; Budinoff, Jason; MacEwen, Howard; Matthews, Gary; Postman, Marc

    2013-09-01

    We present a new approach to building a modular segmented space telescope that greatly leverages the heritage of the Hubble Space Telescope and the James Webb Space Telescope. The modular design in which mirror segments are assembled into identical panels allows for economies of scale and for efficient space assembly that make a 20-m aperture approach cost effective. This assembly approach can leverage NASA's future capabilities and has the power to excite the public's imagination. We discuss the science drivers, basic architecture, technology, and leveraged NASA infrastructure, concluding with a proposed plan for going forward.

  13. Solar Effects on Tensile and Optical Properties of Hubble Space Telescope Silver-Teflon(Registered Trademark) Insulation

    Science.gov (United States)

    deGroh, Kim, K.; Dever, Joyce A.; Snyder, Aaron; Kaminski, Sharon; McCarthy, Catherine E.; Rapoport, Alison L.; Rucker, Rochelle N.

    2006-01-01

    A section of the retrieved Hubble Space Telescope (HST) solar array drive arm (SADA) multilayer insulation (MLI), which experienced 8.25 years of space exposure, was analyzed for environmental durability of the top layer of silver-Teflon (DuPont) fluorinated ethylene propylene (Ag-FEP). Because the SADA MLI had solar and anti-solar facing surfaces and was exposed to the space environment for a long duration, it provided a unique opportunity to study solar effects on the environmental degradation of Ag-FEP, a commonly used spacecraft thermal control material. Data obtained included tensile properties, solar absorptance, surface morphology and chemistry. The solar facing surface was found to be extremely embrittled and contained numerous through-thickness cracks. Tensile testing indicated that the solar facing surface lost 60% of its mechanical strength and 90% of its elasticity while the anti-solar facing surface had ductility similar to pristine FEP. The solar absorptance of both the solar facing surface (0.155 plus or minus 0.032) and the anti-solar facing surface (0.208 plus or minus 0.012) were found to be greater than pristine Ag-FEP (0.074). Solar facing and anti-solar facing surfaces were microscopically textured, and locations of isolated contamination were present on the anti-solar surface resulting in increased localized texturing. Yet, the overall texture was significantly more pronounced on the solar facing surface indicating a synergistic effect of combined solar exposure and increased heating with atomic oxygen erosion. The results indicate a very strong dependence of degradation, particularly embrittlement, upon solar exposure with orbital thermal cycling having a significant effect.

  14. DIFFRACTO-ASTROMETRY WITH HUBBLE SPACE TELESCOPE AND ADAPTIVE OPTICS IMAGES

    Directory of Open Access Journals (Sweden)

    L. J. Sanchez

    2008-01-01

    Full Text Available Como continuación del trabajo de Allen et al. (1974, 2004 acerca de los movimientos internos de sistemas tipo Trapecio, decidimos investigar la posibilidad de realizar astrometría de precisión sobre imágenes del Telescopio Espacial Hubble (HST y sobre imágenes obtenidas con sistemas de óptica Adaptativa (OA. Una región muy bien observada por el HST es la del Trapecio de Orión. Los archivos del HST contienen observaciones de acceso público de este Trapecio tomadas con la WFPC/WFPC2 durante un intervalo de 16 años (1991¿2007. Con la utilización de nuevas técnicas (a las que llamamos Difracto Astrometría determinamos la separación entre las componentes A y E del Trapecio de Orión con una precisión que llega a 0.03" sobre imágenes saturadas. Estas técnicas parecen ser muy prometedoras para explotar no solamente el banco de datos públicos del HST, sino también imágenes obtenidas con telescopios que utilizan técnicas de OA. Para demostrar este último punto, usamos estas mismas técnicas para realizar astrometría de precisición sobre imágenes IR del Trapecio de Orión obtenidas con el sistema Multi-Conjugate Adaptive Optics (MCAO del VLT.

  15. Effect of Solar Exposure on the Atomic Oxygen Erosion of Hubble Space Telescope Aluminized-Teflon Thermal Shields

    Science.gov (United States)

    Guo, Aobo; Ashmead, Claire C.; deGroh, Kim K.

    2012-01-01

    When exposed to low Earth orbital (LEO) environment, external spacecraft materials degrade due to radiation, thermal cycling, micrometeoroid and debris impacts, and atomic oxygen (AO) interaction. Collisions between AO and spacecraft can result in oxidation of external spacecraft surface materials, which can lead to erosion and severe structural and/or optical property deterioration. It is therefore essential to understand the AO erosion yield (Ey), the volume loss per incident oxygen atom (cu cm/atom), of polymers to assure durability of spacecraft materials. The objective of this study was to determine whether solar radiation exposure can increase the rate of AO erosion of polymers in LEO. The material studied was a section of aluminized-Teflon (DuPont) fluorinated ethylene propylene (Al-FEP) thermal shield exposed to space on the Hubble Space Telescope (HST) for 8.25 years. Retrieved samples were sectioned from the circular thermal shield and exposed to ground laboratory thermal energy AO. The results indicate that the average Ey of the solar facing HST Al-FEP was 1.9 10(exp -24)cu cm/atom, while the average Ey of the anti-solar HST Al-FEP was 1.5 10(exp -24)cu cm/atom. The Ey of the pristine samples was 1.6- 1.7 10(exp -24)cu cm/atom. These results indicate that solar exposure affects the post-flight erosion rate of FEP in a plasma asher. Therefore, it likely affects the erosion rate while in LEO.

  16. INVESTIGATING THE CORE MORPHOLOGY-SEYFERT CLASS RELATIONSHIP WITH HUBBLE SPACE TELESCOPE ARCHIVAL IMAGES OF LOCAL SEYFERT GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Rutkowski, M. J.; Hegel, P. R.; Kim, Hwihyun; Windhorst, R. A. [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1404 (United States); Tamura, Kazuyuki [Naruto University of Education, Nakashima, Takashima, Naruto-cho, Naruto-shi 772-8502 (Japan)

    2013-07-01

    The unified model of active galactic nuclei (AGNs) has provided a successful explanation for the observed diversity of AGNs in the local universe. However, recent analysis of multi-wavelength spectral and image data suggests that the unified model is only a partial theory of AGNs, and may need to be augmented to remain consistent with all observations. Recent studies using high spatial resolution ground- and space-based observations of local AGNs show that Seyfert class and the ''core'' (r {approx}< 1 kpc) host-galaxy morphology are correlated. Currently, this relationship has only been established qualitatively, by visual inspection of the core morphologies of low-redshift (z < 0.035) Seyfert host galaxies. We re-establish this empirical relationship in Hubble Space Telescope optical imaging by visual inspection of a catalog of 85 local (D < 63 Mpc) Seyfert galaxies. We also attempt to re-establish the core morphology-Seyfert class relationship using an automated, non-parametric technique that combines both existing classification parameter methods (the adapted CAS and G-M {sub 20}) and a new method which implements the Source Extractor software for feature detection in unsharp-mask images. This new method is designed explicitly to detect dust features in the images. We use our automated approach to classify the morphology of the AGN cores and determine that Sy2 galaxies visually appear, on average, to have more dust features than Sy1. With the exception of this ''dustiness'' however, we do not measure a strong correlation between the dust morphology and the Seyfert class of the host galaxy using quantitative techniques. We discuss the implications of these results in the context of the unified model.

  17. Space Telescopes

    Science.gov (United States)

    2010-01-01

    Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 166 9. Space telescopes Figure 9.1: Paraboloid telescope. In the following sections, NI...planets nearby a brighter star. Normal-incidence telescopes One-mirror telescope The one-mirror telescope (mostly an off-axis paraboloid ; Figure 9.1) has...rotation of the whole instrument (see SUMER/SOHO, Wilhelm et al (1995) and EIS/Hinode, Culhane et al (2007)). The paraboloid field curvature (Petzval

  18. Analysis of Hubble Space Telescope Observations of an Outburst of Comet 29P/Schwassmann-Wachmann 1

    Science.gov (United States)

    Schambeau, Charles Alfred; Fernandez, Yanga R.; Samarasinha, Nalin H.; Kundu, Arunav

    2016-10-01

    We present results of a continuing analysis on the spin state of the enigmatic Comet 29P/Schwassmann-Wachmann 1 (SW1). Previous works have reported possible constraints on the spin state including a non-principal axis state [1] or a rotation period of tens of days [2]. This diversity of published answers highlights the complexity of determining the spin state of an active comet nucleus. Previous work by our group using 3D Monte Carlo coma modeling of ground-based outburst observations from 2008 [3] has placed constraints on the spin period for a set of assumed spin-pole orientations. Due to the nature of the 2008 outburst morphology no constraints on the spin-pole orientation could be found.We present here an analysis of Hubble Space Telescope WFPC2 observations of SW1 shortly after a 1996 outburst [4] with which we have further constrained the spin state. The 0.046-arcsec/pixel scale (176 km/pixel at SW1) of the PC detector gives an order-of-magnitude improvement in spatial resolution over our ground-based observations. Two sets of observations from UT 1996 Mar. 11.3 and 12.1 show the ejected dust forming an asymmetric outflow contained on the sunward side of the coma. A projected outflow velocity of 0.15 ± 0.02 km/s was measured, similar to our measured value from the 2008 observations. Enhancements of the images were performed [5] to bring out subtle variations in coma brightness (i.e., jets) and to allow us to search for signatures of the nucleus' rotation during the outburst. Three curved features are seen in both sets of observations and were modeled using the 3D Monte Carlo coma model [6]. We find a spin period on the order of several days, in agreement with our earlier 2008 analysis.[1] Meech, K. J., et al.: 1993, Astron. J., 106, 1222. [2] Miles, R., et al.: 2016, Icarus, 272, 327. [3] Schambeau, C. A., et al.: 2016, Icarus, submitted. [4] Feldman, P. D., et al.: 1996, AAS/DPS Meeting Abstracts, 28, 1084. [5] Samarasinha, N. and Larson, S.: 2014, Icarus

  19. Extravehicular Activity Probabilistic Risk Assessment Overview for Thermal Protection System Repair on the Hubble Space Telescope Servicing Mission

    Science.gov (United States)

    Bigler, Mark; Canga, Michael A.; Duncan, Gary

    2010-01-01

    The Shuttle Program initiated an Extravehicular Activity (EVA) Probabilistic Risk Assessment (PRA) to assess the risks associated with performing a Shuttle Thermal Protection System (TPS) repair during the Space Transportation System (STS)-125 Hubble repair mission as part of risk trades between TPS repair and crew rescue.

  20. A Lyman Break Galaxy in the Epoch of Reionization from Hubble Space Telescope (HST) Grism Spectroscopy

    Science.gov (United States)

    Rhoads, James E.; Malhotra, Sangeeta; Stern, Daniel K.; Gardner, Jonathan P.; Dickinson, Mark; Pirzkal, Norbert; Spinrad, Hyron; Reddy, Naveen; Dey, Arjun; Hathi, Nimish; hide

    2013-01-01

    Slitless grism spectroscopy from space offers dramatic advantages for studying high redshift galaxies: high spatial resolution to match the compact sizes of the targets, a dark and uniform sky background, and simultaneous observation over fields ranging from five square arcminutes (HST) to over 1000 square arcminutes (Euclid). Here we present observations of a galaxy at z = 6.57 the end of the reioinization epoch identified using slitless HST grism spectra from the PEARS survey (Probing Evolution And Reionization Spectroscopically) and reconfirmed with Keck + DEIMOS. This high redshift identification is enabled by the depth of the PEARS survey. Substantially higher redshifts are precluded for PEARS data by the declining sensitivity of the ACS grism at greater than lambda 0.95 micrometers. Spectra of Lyman breaks at yet higher redshifts will be possible using comparably deep observations with IR-sensitive grisms.

  1. Delayed star formation in isolated dwarf galaxies: Hubble space telescope star formation history of the Aquarius dwarf irregular

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Andrew A. [School of Physical Sciences, University of Tasmania, Private Bag 37, Hobart, Tasmania, 7001 Australia (Australia); Weisz, Daniel R. [Department of Astronomy, University of California at Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Dolphin, Andrew E. [Raytheon, 1151 East Hermans Road, Tucson, AZ 85706 (United States); Skillman, Evan D. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55441 (United States); McConnachie, Alan W. [NRC Herzberg Institute of Astrophysics, Dominion Astrophysical Observatory, Victoria, BC, V9E 2E7 Canada (Canada); Brooks, Alyson M. [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Leaman, Ryan, E-mail: andrew.cole@utas.edu.au, E-mail: drw@ucsc.edu, E-mail: adolphin@raytheon.com, E-mail: skillman@astro.umn.edu, E-mail: alan.mcconnachie@nrc-cnrc.gc.ca, E-mail: abrooks@physics.rutgers.edu, E-mail: rleaman@iac.es [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain)

    2014-11-01

    We have obtained deep images of the highly isolated (d = 1 Mpc) Aquarius dwarf irregular galaxy (DDO 210) with the Hubble Space Telescope Advanced Camera for Surveys. The resulting color-magnitude diagram (CMD) reaches more than a magnitude below the oldest main-sequence turnoff, allowing us to derive the star formation history (SFH) over the entire lifetime of the galaxy with a timing precision of ≈10% of the lookback time. Using a maximum likelihood fit to the CMD we find that only ≈10% of all star formation in Aquarius took place more than 10 Gyr ago (lookback time equivalent to redshift z ≈ 2). The star formation rate increased dramatically ≈6-8 Gyr ago (z ≈ 0.7-1.1) and then declined until the present time. The only known galaxy with a more extreme confirmed delay in star formation is Leo A, a galaxy of similar M {sub H} {sub I}/M {sub *}, dynamical mass, mean metallicity, and degree of isolation. The delayed stellar mass growth in these galaxies does not track the mean dark matter accretion rate from CDM simulations. The similarities between Leo A and Aquarius suggest that if gas is not removed from dwarf galaxies by interactions or feedback, it can linger for several gigayears without cooling in sufficient quantity to form stars efficiently. We discuss possible causes for the delay in star formation including suppression by reionization and late-time mergers. We find reasonable agreement between our measured SFHs and select cosmological simulations of isolated dwarfs. Because star formation and merger processes are both stochastic in nature, delayed star formation in various degrees is predicted to be a characteristic (but not a universal) feature of isolated small galaxies.

  2. The star formation histories of local group dwarf galaxies. I. Hubble space telescope/wide field planetary camera 2 observations

    Energy Technology Data Exchange (ETDEWEB)

    Weisz, Daniel R. [Department of Astronomy, University of California at Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Skillman, Evan D. [Minnesota Institute for Astrophysics, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Holtzman, Jon [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger Street, Las Cruces, NM 88003 (United States); Gilbert, Karoline M.; Dalcanton, Julianne J.; Williams, Benjamin F., E-mail: drw@ucsc.edu [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States)

    2014-07-10

    We present uniformly measured star formation histories (SFHs) of 40 Local Group (LG) dwarf galaxies based on color-magnitude diagram (CMD) analysis from archival Hubble Space Telescope imaging. We demonstrate that accurate SFHs can be recovered from CMDs that do not reach the oldest main sequence turn-off (MSTO), but emphasize that the oldest MSTO is critical for precisely constraining the earliest epochs of star formation. We find that: (1) the average lifetime SFHs of dwarf spheroidals (dSphs) can be approximated by an exponentially declining SFH with τ ∼ 5 Gyr; (2) lower luminosity dSphs are less likely to have extended SFHs than more luminous dSphs; (3) the average SFHs of dwarf irregulars (dIrrs), transition dwarfs, and dwarf ellipticals can be approximated by the combination of an exponentially declining SFH (τ ∼ 3-4 Gyr) for lookback ages >10-12 Gyr ago and a constant SFH thereafter; (4) the observed fraction of stellar mass formed prior to z = 2 ranges considerably (80% for galaxies with M < 10{sup 5} M{sub ☉} to 30% for galaxies with M > 10{sup 7} M{sub ☉}) and is largely explained by environment; (5) the distinction between 'ultra-faint' and 'classical' dSphs is arbitrary; (6) LG dIrrs formed a significantly higher fraction of stellar mass prior to z = 2 than the Sloan Digital Sky Survey galaxies from Leitner and the SFHs from the abundance matching models of Behroozi et al. This may indicate higher than expected star formation efficiencies at early times in low mass galaxies. Finally, we provide all the SFHs in tabulated electronic format for use by the community.

  3. Hubble Space Telescope Observations of the Afterglow, Supernova and Host Galaxy Associated with the Extremely Bright GRB 130427A

    Science.gov (United States)

    Levan, A.J.; Tanvir, N. R.; Fruchter, A. S.; Hjorth, J.; Pian, E.; Mazzali, P.; Hounsell, R. A.; Perley, D. A.; Cano, Z.; Graham, J.; hide

    2014-01-01

    We present Hubble Space Telescope (HST) observations of the exceptionally bright and luminous Swift gamma-ray burst, GRB 130427A. At z=0.34 this burst affords an excellent opportunity to study the supernova and host galaxy associated with an intrinsically extremely luminous burst (E(sub iso) greater than 10(exp 54) erg): more luminous than any previous GRB with a spectroscopically associated supernova. We use the combination of the image quality, UV capability and and invariant PSF of HST to provide the best possible separation of the afterglow, host and supernova contributions to the observed light approximately 17 rest-frame days after the burst utilising a host subtraction spectrum obtained 1 year later. Advanced Camera for Surveys (ACS) grism observations show that the associated supernova, SN 2013cq, has an overall spectral shape and luminosity similar to SN 1998bw (with a photospheric velocity, vph approximately 15,000 kilometers per second). The positions of the bluer features are better matched by the higher velocity SN 2010bh (vph approximately 30,000 kilometers per second), but SN 2010bh (vph approximately 30,000 kilometers per second but this SN is significantly fainter, and fails to reproduce the overall spectral shape, perhaps indicative of velocity structure in the ejecta. We find that the burst originated approximately 4 kpc from the nucleus of a moderately star forming (1 Solar Mass yr(exp-1)), possibly interacting disc galaxy. The absolute magnitude, physical size and morphology of this galaxy, as well as the location of the GRB within it are also strikingly similar to those of GRB980425SN 1998bw. The similarity of supernovae and environment from both the most luminous and least luminous GRBs suggests broadly similar progenitor stars can create GRBs across six orders of magnitude in isotropic energy.

  4. Atmospheric Characterization of Five Hot Jupiters with the Wide Field Camera 3 on the Hubble Space Telescope

    Science.gov (United States)

    Ranjan, Sukrit; Charbonneau, David; Desert, Jean-Michel; Madhusudhan, Nikku; Deming, Drake; Wilkins, Ashlee; Mandell, Avi M.

    2014-01-01

    We probe the structure and composition of the atmospheres of five hot Jupiter exoplanets using the Hubble Space Telescope Wide Field Camera 3 (WFC3) instrument. We use the G141 grism (1.1-1.7 micrometers) to study TrES-2b, TrES-4b, and CoRoT-1b in transit; TrES-3b in secondary eclipse; and WASP-4b in both. This wavelength region includes a predicted absorption feature from water at 1.4 micrometers, which we expect to be nondegenerate with the other molecules that are likely to be abundant for hydrocarbon-poor (e.g., solar composition) hot Jupiter atmospheres. We divide our wavelength regions into 10 bins. For each bin we produce a spectrophotometric light curve spanning the time of transit or eclipse. We correct these light curves for instrumental systematics without reference to an instrument model. For our transmission spectra, our mean 1s precision per bin corresponds to variations of 2.1, 2.8, and 3.0 atmospheric scale heights for TrES-2b, TrES-4b, and CoRoT-1b, respectively. We find featureless spectra for these three planets. We are unable to extract a robust transmission spectrum for WASP-4b. For our dayside emission spectra, our mean 1 sigma precision per bin corresponds to a planet-to-star flux ratio of 1.5 x 10(exp -4) and 2.1 x 10(exp -4) for WASP-4b and TrES-3b, respectively. We combine these estimates with previous broadband measurements and conclude that for both planets isothermal atmospheres are disfavored. We find no signs of features due to water. We confirm that WFC3 is suitable for studies of transiting exoplanets, but in staring mode multivisit campaigns are necessary to place strong constraints on water abundance.

  5. The Hubble Space Telescope UV Legacy Survey of Galactic globular clusters - IX. The Atlas of multiple stellar populations

    Science.gov (United States)

    Milone, A. P.; Piotto, G.; Renzini, A.; Marino, A. F.; Bedin, L. R.; Vesperini, E.; D'Antona, F.; Nardiello, D.; Anderson, J.; King, I. R.; Yong, D.; Bellini, A.; Aparicio, A.; Barbuy, B.; Brown, T. M.; Cassisi, S.; Ortolani, S.; Salaris, M.; Sarajedini, A.; van der Marel, R. P.

    2017-01-01

    We use high-precision photometry of red-giant-branch (RGB) stars in 57 Galactic globular clusters (GCs), mostly from the `Hubble Space Telescope (HST) UV Legacy Survey of Galactic GCs', to identify and characterize their multiple stellar populations. For each cluster the pseudo-two-colour diagram (or `chromosome map') is presented, built with a suitable combination of stellar magnitudes in the F275W, F336W, F438W, and F814W filters that maximizes the separation between multiple populations. In the chromosome map of most GCs (type-I clusters), stars separate in two distinct groups that we identify with the first (1G) and the second generation (2G). This identification is further supported by noticing that 1G stars have primordial (oxygen-rich, sodium-poor) chemical composition, whereas 2G stars are enhanced in sodium and depleted in oxygen. This 1G-2G separation is not possible for a few GCs where the two sequences have apparently merged into an extended, continuous sequence. In some GCs (type-II clusters) the 1G and/or the 2G sequences appear to be split, hence displaying more complex chromosome maps. These clusters exhibit multiple subgiant branches (SGBs) also in purely optical colour-magnitude diagrams, with the fainter SGB joining into a red RGB which is populated by stars with enhanced heavy-element abundance. We measure the RGB width by using appropriate colours and pseudo-colours. When the metallicity dependence is removed, the RGB width correlates with the cluster mass. The fraction of 1G stars ranges from ˜8 per cent to ˜67 per cent and anticorrelates with the cluster mass, indicating that incidence and complexity of the multiple population phenomenon both increase with cluster mass.

  6. Hubble space telescope observations of the afterglow, supernova, and host galaxy associated with the extremely bright GRB 130427A

    Energy Technology Data Exchange (ETDEWEB)

    Levan, A. J. [Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Tanvir, N. R.; Wiersema, K. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH (United Kingdom); Fruchter, A. S.; Hounsell, R. A.; Graham, J. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Hjorth, J.; Fynbo, J. P. U. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Pian, E. [INAF, Trieste Astronomical Observatory, via G.B. Tiepolo 11, I-34143 Trieste (Italy); Mazzali, P. [Astrophysics Research Institute, Liverpool John Moores University, IC2 Liverpool Science Park 146 Brownlow Hill, Liverpool L3 5RF (United Kingdom); Perley, D. A. [Department of Astronomy, California Institute of Technology, MC 249-17, 1200 East California Blvd., Pasadena, CA 91125 (United States); Cano, Z. [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, 107 Reykjavik (Iceland); Cenko, S. B. [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Kouveliotou, C. [Science and Technology Office, ZP12, NASA/Marshall Space Flight Center, Huntsville, AL 35812 (United States); Pe' er, A. [Department of Physics, University College Cork, Cork (Ireland); Misra, K., E-mail: a.j.levan@warwick.ac.uk [Aryabhatta Research Institute of Observational Sciences, Manora Peak, Nainital-263 002 (India)

    2014-09-10

    We present Hubble Space Telescope (HST) observations of the exceptionally bright and luminous Swift gamma-ray burst (GRB), GRB 130427A. At z = 0.34, this burst affords an excellent opportunity to study the supernova (SN) and host galaxy associated with an intrinsically extremely luminous burst (E {sub iso} > 10{sup 54} erg): more luminous than any previous GRB with a spectroscopically associated SN. We use the combination of the image quality, UV capability, and invariant point-spread function of HST to provide the best possible separation of the afterglow, host, and SN contributions to the observed light ∼17 rest-frame days after the burst, utilizing a host subtraction spectrum obtained one year later. Advanced Camera for Surveys grism observations show that the associated SN, SN 2013cq, has an overall spectral shape and luminosity similar to SN 1998bw (with a photospheric velocity, v {sub ph} ∼ 15, 000 km s{sup –1}). The positions of the bluer features are better matched by the higher velocity SN 2010bh (v {sub ph} ∼ 30, 000 km s{sup –1}), but this SN is significantly fainter and fails to reproduce the overall spectral shape, perhaps indicative of velocity structure in the ejecta. We find that the burst originated ∼4 kpc from the nucleus of a moderately star forming (1 M {sub ☉} yr{sup –1}), possibly interacting disk galaxy. The absolute magnitude, physical size, and morphology of this galaxy, as well as the location of the GRB within it, are also strikingly similar to those of GRB 980425/SN 1998bw. The similarity of the SNe and environment from both the most luminous and least luminous GRBs suggests that broadly similar progenitor stars can create GRBs across six orders of magnitude in isotropic energy.

  7. Atmospheric Characterization of Five Hot Jupiters with the Wide Field Camera 3 on the Hubble Space Telescope

    Science.gov (United States)

    Ranjan, Sukrit; Charbonneau, David; Desert, Jean-Michel; Madhusudhan, Nikku; Deming, Drake; Wilkins, Ashlee; Mandell, Avi M.

    2014-01-01

    We probe the structure and composition of the atmospheres of five hot Jupiter exoplanets using the Hubble Space Telescope Wide Field Camera 3 (WFC3) instrument. We use the G141 grism (1.1-1.7 micrometers) to study TrES-2b, TrES-4b, and CoRoT-1b in transit; TrES-3b in secondary eclipse; and WASP-4b in both. This wavelength region includes a predicted absorption feature from water at 1.4 micrometers, which we expect to be nondegenerate with the other molecules that are likely to be abundant for hydrocarbon-poor (e.g., solar composition) hot Jupiter atmospheres. We divide our wavelength regions into 10 bins. For each bin we produce a spectrophotometric light curve spanning the time of transit or eclipse. We correct these light curves for instrumental systematics without reference to an instrument model. For our transmission spectra, our mean 1s precision per bin corresponds to variations of 2.1, 2.8, and 3.0 atmospheric scale heights for TrES-2b, TrES-4b, and CoRoT-1b, respectively. We find featureless spectra for these three planets. We are unable to extract a robust transmission spectrum for WASP-4b. For our dayside emission spectra, our mean 1 sigma precision per bin corresponds to a planet-to-star flux ratio of 1.5 x 10(exp -4) and 2.1 x 10(exp -4) for WASP-4b and TrES-3b, respectively. We combine these estimates with previous broadband measurements and conclude that for both planets isothermal atmospheres are disfavored. We find no signs of features due to water. We confirm that WFC3 is suitable for studies of transiting exoplanets, but in staring mode multivisit campaigns are necessary to place strong constraints on water abundance.

  8. Atmospheric characterization of five hot Jupiters with the wide field Camera 3 on the Hubble space telescope

    Energy Technology Data Exchange (ETDEWEB)

    Ranjan, Sukrit; Charbonneau, David [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Désert, Jean-Michel [Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States); Madhusudhan, Nikku [Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06511 (United States); Deming, Drake; Wilkins, Ashlee [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Mandell, Avi M., E-mail: sranjan@cfa.harvard.edu [NASA' s Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2014-04-20

    We probe the structure and composition of the atmospheres of five hot Jupiter exoplanets using the Hubble Space Telescope Wide Field Camera 3 (WFC3) instrument. We use the G141 grism (1.1-1.7 μm) to study TrES-2b, TrES-4b, and CoRoT-1b in transit; TrES-3b in secondary eclipse; and WASP-4b in both. This wavelength region includes a predicted absorption feature from water at 1.4 μm, which we expect to be nondegenerate with the other molecules that are likely to be abundant for hydrocarbon-poor (e.g., solar composition) hot Jupiter atmospheres. We divide our wavelength regions into 10 bins. For each bin we produce a spectrophotometric light curve spanning the time of transit or eclipse. We correct these light curves for instrumental systematics without reference to an instrument model. For our transmission spectra, our mean 1σ precision per bin corresponds to variations of 2.1, 2.8, and 3.0 atmospheric scale heights for TrES-2b, TrES-4b, and CoRoT-1b, respectively. We find featureless spectra for these three planets. We are unable to extract a robust transmission spectrum for WASP-4b. For our dayside emission spectra, our mean 1σ precision per bin corresponds to a planet-to-star flux ratio of 1.5 × 10{sup –4} and 2.1 × 10{sup –4} for WASP-4b and TrES-3b, respectively. We combine these estimates with previous broadband measurements and conclude that for both planets isothermal atmospheres are disfavored. We find no signs of features due to water. We confirm that WFC3 is suitable for studies of transiting exoplanets, but in staring mode multivisit campaigns are necessary to place strong constraints on water abundance.

  9. The nuclear regions of NGC 3311 and NGC 7768 imaged with the Hubble Space Telescope Planetary Camera

    Science.gov (United States)

    Grillmair, Carl J.; Faber, S.M.; Lauer, Tod R.; Baum, William A.; Lynds, Roger C.; O'Neil, Earl J., Jr.; Shaya, Edward J.

    1994-01-01

    We present high-resolution, V band images of the central regions of the brightest cluster ellipticals NGC 3311 and NGC 7768 taken with the Planetary Camera of the Hubble Space Telescope. The nuclei of both galaxies are found to be obscured by dust, though the morphology of the dust is quite different in the two cases. The dust cloud which obscures the central 3 arcsec of NGC 3311 is complex and irregular, while the central region of NGC 7768 contains a disk of material similar in appearance and scale to that recently observed in HST images of NGC 4261. The bright, relatively blue source detected in ground-based studies of NGC 3311 is marginally resolved and is likely to be a site of ongoing star formation. We examine the distribution of globular clusters in the central regions of NGC 3311. The gradient in the surface density profile of the cluster system is significantly shallower than that found by previous investigators at larger radii. We find a core radius for the cluster distribution of 12 plus or minus 3 kpc, which is even larger than the core radius of the globular cluster system surrounding M87. It is also an order of magnitude larger than the upper limit on the core radius of NGC 3311's stellar light and suggests that the central field-star population and the globular cluster system are dynamically distinct. We briefly discuss possible sources for the cold/warm interstellar material in early-type galaxies. While the issue has not been resolved, models which involve galactic wind failure appear to be mo st naturally consistent with the observations.

  10. Hubble Space Telescope Detection of the Millisecond Pulsar J2124-3358 and its Far-ultraviolet Bow Shock Nebula

    Science.gov (United States)

    Rangelov, B.; Pavlov, G. G.; Kargaltsev, O.; Reisenegger, A.; Guillot, S.; van Kerkwijk, M. H.; Reyes, C.

    2017-02-01

    We observed the nearby millisecond pulsar J2124–3358 with the Hubble Space Telescope in broad far-UV (FUV) and optical filters. The pulsar is detected in both bands with fluxes F(1250–2000 Å) = (2.5 ± 0.3) × 10‑16 erg s‑1 cm‑2 and F(3800–6000 Å) = (6.4 ± 0.4) × 10‑17 erg s‑1 cm‑2, which corresponds to luminosities of ≈5.8 × 1027 and 1.4 × 1027 erg s‑1, for d = 410 pc and E(B ‑ V) = 0.03. The optical-FUV spectrum can be described by a power-law model, {f}ν \\propto {ν }α , with slope α = 0.18–0.48 for a conservative range of color excess, E(B ‑ V) = 0.01–0.08. Since a spectral flux rising with frequency is unusual for pulsar magnetospheric emission in this frequency range, it is possible that the spectrum is predominantly magnetospheric (power law with α neutron star surface in the FUV. For a neutron star radius of 12 km, the surface temperature would be between 0.5 × 105 and 2.1 × 105 K for α ranging from ‑1 to 0, E(B ‑ V) = 0.01–0.08, and d = 340–500 pc. In addition to the pulsar, the FUV images reveal extended emission that is spatially coincident with the known Hα bow shock, making PSR J2124–3358 the second pulsar (after PSR J0437‑4715) with a bow shock detected in the FUV.

  11. UV/Visible Telescope with Hubble Disposal

    Science.gov (United States)

    Benford, Dominic J.

    2013-01-01

    Submission Overview: Our primary objective is to convey a sense of the significant advances possible in astrophysics investigations for major Cosmic Origins COR program goals with a 2.4m telescope asset outfitted with one or more advanced UV visible instruments. Several compelling science objectives were identified based on community meetings these science objectives drove the conceptual design of instruments studied by the COR Program Office during July September 2012. This RFI submission encapsulates the results of that study, and suggests that a more detailed look into the instrument suite should be conducted to prove viability and affordability to support the demonstrated scientific value. This study was conducted in the context of a larger effort to consider the options available for a mission to dispose safely of Hubble hence, the overall architecture considered for the mission we studied for the 2.4m telescope asset included resource sharing. This mitigates combined cost and risk and provides naturally for a continued US leadership role in astrophysics with an advanced, general-purpose UV visible space telescope.

  12. Hubble and Spitzer Space Telescope Observations of the Debris Disk around the nearby K Dwarf HD 92945

    Science.gov (United States)

    Golimowski, D. A.; Krist, J. E.; Stapelfeldt, K. R.; Chen, C. H.; Ardila, D. R.; Bryden, G.; Clampin, M.; Ford, H. C.; Illingworth, G. D.; Plavchan, P.; Rieke, G. H.; Su, K. Y. L.

    2011-07-01

    We present the first resolved images of the debris disk around the nearby K dwarf HD 92945, obtained with the Hubble Space Telescope's (HST 's) Advanced Camera for Surveys. Our F606W (Broad V) and F814W (Broad I) coronagraphic images reveal an inclined, axisymmetric disk consisting of an inner ring about 2farcs0-3farcs0 (43-65 AU) from the star and an extended outer disk whose surface brightness declines slowly with increasing radius approximately 3farcs0-5farcs1 (65-110 AU) from the star. A precipitous drop in the surface brightness beyond 110 AU suggests that the outer disk is truncated at that distance. The radial surface-density profile is peaked at both the inner ring and the outer edge of the disk. The dust in the outer disk scatters neutrally but isotropically, and it has a low V-band albedo of 0.1. This combination of axisymmetry, ringed and extended morphology, and isotropic neutral scattering is unique among the 16 debris disks currently resolved in scattered light. We also present new infrared photometry and spectra of HD 92945 obtained with the Spitzer Space Telescope's Multiband Imaging Photometer and InfraRed Spectrograph. These data reveal no infrared excess from the disk shortward of 30 μm and constrain the width of the 70 μm source to lsim180 AU. Assuming that the dust comprises compact grains of astronomical silicate with a surface-density profile described by our scattered-light model of the disk, we successfully model the 24-350 μm emission with a minimum grain size of a min = 4.5 μm and a size distribution proportional to a -3.7 throughout the disk, but with maximum grain sizes of 900 μm in the inner ring and 50 μm in the outer disk. Together, our HST and Spitzer observations indicate a total dust mass of ~0.001M ⊕. However, our observations provide contradictory evidence of the dust's physical characteristics: its neutral V-I color and lack of 24 μm emission imply grains larger than a few microns, but its isotropic scattering and low

  13. Detection of CO Cameron band emission in comet P/Hartley 2 (1991 XV) with the Hubble Space Telescope

    Science.gov (United States)

    Weaver, H. A.; Feldman, P. D.; Mcphate, J. B.; A'Hearn, M. F.; Arpigny, C.; Smith, T. E.

    1994-01-01

    Ultraviolet (UV) spectra of comet P/Hartley 2 (1991 XV) taken with the Faint Object Spectrograph (FOS) on the Hubble Space Telescope (HST) in 1991 September reveal several bands of the Cameron system of CO (a 3 Pi-X 1 Sigma). These band are most likely due to 'prompt' emission from CO2 and, thus, provide a direct tracer of the CO2 abundance in the nucleus. Photodissociative excitation of CO2 is probably the largest contributor to the Cameron band emission, but significant contributions from electron impact excitation of CO, electron impact dissociation of CO2, and dissociative recombination of CO2(+), are also possible. Using our estimate that photodissociative excitation is responsible for approximately 60% of the total excitation of the Cameron system, we derive Q(sub CO2) approximately 2.6 x 10(exp 27) molecules/s, which implies CO2/H20 approximately 4%. If all of the Cameron band emission is due to photodissociative excitation, then CO2/H2O = 7 +/- 2%. For the largest possible contributions from the other excitation mechanisms considered, the CO2 abundance could be as a small as aproximately 2-3%. We did not detect CO Fourth Positive Group emission in our data and derive an upper limit of CO/H2O less than or equal to 1% (3 sigma) for CO coming directly from the nucleus. Comparison of the relative CO2 and CO abundances in P/Hartley 2 to those in P/Halley (CO2/H2O approximately 3%-4%, CO/H20 approximately 4% for the nucleus source) indicates that selective devolatilization of the nucleus may have occurred for P/Hartley 2. A relatively large CO2/CO ratio (i.e., approximately greater than 1) seems to be a common property of cometary nuclei. Since gas phase chemistry, in either the solar nebula or the interstellar medium (ISM), appears incapable of producing large relative CO2 abundances, the CO2 in cometary nuclei is probably produced either by UV and/or cosmic ray irradiation of ISM grains prior to the formation of the Solar System, or by condensation

  14. CLOUD STRUCTURE OF THE NEAREST BROWN DWARFS: SPECTROSCOPIC VARIABILITY OF LUHMAN 16AB FROM THE HUBBLE SPACE TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Buenzli, Esther [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Saumon, Didier [Los Alamos National Laboratory, Mail Stop F663, Los Alamos, NM 87545 (United States); Marley, Mark S. [NASA Ames Research Center, MS-245-3, Moffett Field, CA 94035 (United States); Apai, Dániel [Department of Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Radigan, Jacqueline; Reid, I. Neill [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Bedin, Luigi R. [INAF-Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Morley, Caroline V., E-mail: buenzli@mpia.de [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)

    2015-01-10

    The binary brown dwarf WISE J104915.57–531906.1 (also Luhman 16AB), composed of a late-L and early-T dwarf, is a prototypical L/T transition flux reversal binary located at a distance of only 2 pc. Luhman 16B is a known variable whose light curves evolve rapidly. We present a spatially resolved spectroscopic time-series of Luhman 16A and B covering 6.5 hr using the Hubble Space Telescope/WFC3 at 1.1-1.66 μm. The small, count-dependent variability of Luhman 16A at the beginning of the observations likely stems from instrumental systematics; Luhman 16A appears non-variable above ≈0.4%. Its spectrum is well fit by a single cloud layer with intermediate cloud thickness (f {sub sed} = 2, T {sub eff} = 1200 K). Luhman 16B varies at all wavelengths with peak-to-valley amplitudes of 7%-11%. The amplitude and light curve shape changes over only one rotation period. The lowest relative amplitude is found in the deep water absorption band at 1.4 μm, otherwise it mostly decreases gradually from the blue to the red edge of the spectrum. This is very similar to the other two known highly variable early-T dwarfs. A two-component cloud model accounts for most of the variability, although small deviations are seen in the water absorption band. We fit the mean spectrum and relative amplitudes with a linear combination of two models of a warm, thinner cloud (T {sub eff} = 1300 K, f {sub sed} = 3) and a cooler, thicker cloud (T {sub eff} = 1000-1100 K, f {sub sed} = 1), assuming out-of-equilibrium atmospheric chemistry. A model with parameters as for Luhman 16A except for the addition of cloud holes cannot reproduce the variability of Luhman 16B, indicating more complex cloud evolution through the L/T transition. The projected separation of the binary has decreased by ≈0.''3 in eight months.

  15. A HUBBLE SPACE TELESCOPE/COSMIC ORIGINS SPECTROGRAPH SEARCH FOR WARM-HOT BARYONS IN THE Mrk 421 SIGHT LINE

    Energy Technology Data Exchange (ETDEWEB)

    Danforth, Charles W.; Stocke, John T.; Keeney, Brian A.; Penton, Steven V.; Shull, J. Michael; Yao Yangsen; Green, James C., E-mail: danforth@colorado.edu [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States)

    2011-12-10

    Thermally broadened Ly{alpha} absorbers (BLAs) offer an alternate method to using highly ionized metal absorbers (O VI, O VII, etc.) to probe the warm-hot intergalactic medium (WHIM, T = 10{sup 5}-10{sup 7} K). Until now, WHIM surveys via BLAs have been no less ambiguous than those via far-UV and X-ray metal-ion probes. Detecting these weak, broad features requires background sources with a well-characterized far-UV continuum and data of very high quality. However, a recent Hubble Space Telescope/Cosmic Origins Spectrograph (COS) observation of the z = 0.03 blazar Mrk 421 allows us to perform a metal-independent search for WHIM gas with unprecedented precision. The data have high signal-to-noise ratio (S/N Almost-Equal-To 50 per {approx}20 km s{sup -1} resolution element) and the smooth, power-law blazar spectrum allows a fully parametric continuum model. We analyze the Mrk 421 sight line for BLA absorbers, particularly for counterparts to the proposed O VII WHIM systems reported by Nicastro et al. based on Chandra/Low Energy Transmission Grating observations. We derive the Ly{alpha} profiles predicted by the X-ray observations. The S/N of the COS data is high (S/N Almost-Equal-To 25 pixel{sup -1}), but much higher S/N can be obtained by binning the data to widths characteristic of the expected BLA profiles. With this technique, we are sensitive to WHIM gas over a large (N{sub H}, T) parameter range in the Mrk 421 sight line. We rule out the claimed Nicastro et al. O VII detections at their nominal temperatures (T {approx} 1-2 Multiplication-Sign 10{sup 6} K) and metallicities (Z = 0.1 Z{sub Sun }) at {approx}> 2{sigma} level. However, WHIM gas at higher temperatures and/or higher metallicities is consistent with our COS non-detections.

  16. Exploring the NRO Opportunity for a Hubble-Sized Wide-Field Near-IR Space Telescope - New WFIRST

    Science.gov (United States)

    Dressler, Alan; Spergel, David; Mountain, Matt; Postman, Mark; Elliott, Erin; Bendek, Eduardo; Bennett, David; Dalcanton, Julianne; Gaudi, Scott; Gehrels, Neil; hide

    2013-01-01

    We discuss scientific, technical, and programmatic issues related to the use of an NRO 2.4m telescope for the WFIRST initiative of the 2010 Decadal Survey. We show that this implementation of WFIRST, which we call "NEW WFIRST," would achieve the goals of the NWNH Decadal Survey for the WFIRST core programs of Dark Energy and Microlensing Planet Finding, with the crucial benefit of deeper and/or wider near-IR surveys for GO science and a potentially Hubble-like Guest Observer program. NEW WFIRST could also include a coronagraphic imager for direct detection of dust disks and planets around neighboring stars, a high-priority science and technology precursor for future ambitious programs to image Earth-like planets around neighboring stars.

  17. Exploring the NRO Opportunity for a Hubble-sized Wide-field Near-IR Space Telescope -- NEW WFIRST

    CERN Document Server

    Dressler, Alan; Mountain, Matt; Postman, Marc; Elliott, Erin; Bendek, Eduardo; Bennett, David; Dalcanton, Julianne; Gaudi, Scott; Gehrels, Neil; Guyon, Olivier; Hirata, Christopher; Kalirai, Jason; Kasdin, N Jeremy; Kruk, Jeff; Macintosh, Bruce; Malhotra, Sangeeta; Penny, Matthew; Perlmutter, Saul; Rieke, George; Riess, Adam; Rhoads, James; Shaklan, Stuart; Somerville, Rachel; Stern, Daniel; Thompson, Rodger; Weinberg, David

    2012-01-01

    We discuss scientific, technical and programmatic issues related to the use of an NRO 2.4m telescope for the WFIRST initiative of the 2010 Decadal Survey. We show that this implementation of WFIRST, which we call "NEW WFIRST," would achieve the goals of the NWNH Decadal Survey for the WFIRST core programs of Dark Energy and Microlensing Planet Finding, with the crucial benefit of deeper and/or wider near-IR surveys for GO science and a potentially Hubble-like Guest Observer program. NEW WFIRST could also include a coronagraphic imager for direct detection of dust disks and planets around neighboring stars, a high-priority science and technology precursor for future ambitious programs to image Earth-like planets around neighboring stars.

  18. A High Angular Resolution Survey of Massive Stars in Cygnus OB2: Results from the Hubble Space Telescope Fine Guidance Sensors

    CERN Document Server

    Caballero-Nieves, Saida M; Gies, Douglas R; Wallace, Debra J; DeGioia-Eastwood, Katherine; Herrero, Artemio; Jao, Wei-Chun; Mason, Brian D; Massey, Philip; Moffat, Anthony F J; Walborn, Nolan R

    2013-01-01

    We present results of a high angular resolution survey of massive OB stars in the Cygnus OB2 association that we conducted with the Fine Guidance Sensor 1R (FGS1r) on the Hubble Space Telescope. FGS1r is able to resolve binary systems with a magnitude difference delta-V 60%. One of the new discoveries is a companion to the hypergiant star MT 304 = Cyg OB2-12, and future measurements of orbital motion should provide mass estimates for this very luminous star.

  19. Hubble Space Telescope STIS observations of GRB 000301C: CCD imaging and near-ultraviolet MAMA spectroscopy

    DEFF Research Database (Denmark)

    Smette, A.; Fruchter, A.S.; Gull, T.R.

    2001-01-01

    We present Space Telescope Imaging Spectrograph observations of the optical transient (OT) counterpart of the c-ray burster GRB 000301C obtained 5 days after the burst, on 2000 March 6. CCD clear-aperture imaging reveals a R similar or equal to 21.50 +/- 0.15 source with no apparent host galaxy. ...

  20. Hubble Space Telescope STIS Observations of GRB 000301C: CCD Imaging and Near-Ultraviolet MAMA Spectroscopy

    NARCIS (Netherlands)

    Smette, A.; Fruchter, A.S.; Gull, Th.R.; Sahu, K.C.; Petro, L.; Ferguson, H.; Rhoads, J.; Lindler, D.J.; Wijers, R.A.M.J.

    2001-01-01

    We present Space Telescope Imaging Spectrograph observations of the optical transient (OT) counterpart of the gamma-ray burster GRB 000301C obtained 5 days after the burst, on 2000 March 6. CCD clear-aperture imaging reveals a R~=21.50+/-0.15 source with no apparent host galaxy. An 8000 s, 1150

  1. Hubble Space Telescope STIS Observations of GRB 000301C: CCD Imaging and Near-Ultraviolet MAMA Spectroscopy

    NARCIS (Netherlands)

    Smette, A.; Fruchter, A.S.; Gull, Th.R.; Sahu, K.C.; Petro, L.; Ferguson, H.; Rhoads, J.; Lindler, D.J.; Wijers, R.A.M.J.

    2001-01-01

    We present Space Telescope Imaging Spectrograph observations of the optical transient (OT) counterpart of the gamma-ray burster GRB 000301C obtained 5 days after the burst, on 2000 March 6. CCD clear-aperture imaging reveals a R~=21.50+/-0.15 source with no apparent host galaxy. An 8000 s, 1150 Å

  2. Recovery of 29 Second Oscillations in Hubble Space Telescope Eclipse Observations of the Cataclysmic Variable UX Ursae Majoris

    Science.gov (United States)

    Knigge, Christian; Drake, Nick; Long, Knox S.; Wade, Richard A.; Horne, Keith; Baptista, Raymundo

    1998-01-01

    Low-amplitude (approximately 0.5%) 29 s oscillations have been detected in Hubble Space Telescope Faint Object Spectrograph eclipse observations of the nova-like cataclysmic variable UX UMa. These are the same dwarf nova-type oscillations that were originally discovered in this system in 1972. The 29 s oscillations are seen in one pair of eclipse sequences obtained with the FOS/PRISM in 1994 November but not in a similar pair obtained with the FOS/GI60L grating in August of the same year. The oscillations in the PRISM data are sinusoidal to within the small observational errors and undergo an approximately - 360' phase shift during eclipses (i.e., one cycle is lost). The amplitudes are highest at pre-eclipse orbital phases and exhibit a rather gradual eclipse whose shape is roughly similar to, although perhaps slightly narrower than, LTX UMa's overall light curve in the PRISM bandpass (2000-8000 A). Spectra of the oscillations have been constructed from pre-, mid, and post-eclipse data segments of the November observations. The spectra obtained from the out-of-eclipse segments are extremely blue, and only lower limits can be placed on the temperature of the source that dominates the modulated flux at these orbital phases. Lower limits derived from blackbody (stellar atmosphere) model fits to these data are >or equal to 95,000 K (> or equal to 85,000 K); the corresponding upper limits on the projected area of this source are all less than 2% of the white dwarf (WD) surface area. By contrast, oscillation spectra derived from mid- eclipse data segments are much redder. Fits to these spectra yield temperature estimates in the range 20,000 K approximately greater T and T approximately less than 30,000 K for both blackbody and stellar atmosphere models and corresponding projected areas of a few percent of the WD surface area. These estimates are subject to revision if the modulated emission is optically thin. We suggest that the ultimate source of the oscillations is a

  3. The Hubble Space Telescope quasar absorption line key project. 6: Properties of the metal-rich systems

    Science.gov (United States)

    Bergeron, Jacqueline; Petitjean, Patrick; Sargent, W. L. W.; Bahcall, John N.; Boksenberg, Alec; Hartig, George F.; Jannuzi, Buell T.; Kirhakos, Sofia; Savage, Blair D.; Schneider, Donald P.

    1994-01-01

    We present an analysis of the properties of a sample of 18 metal-rich, low-redshift z(sub abs) much less than z(sub em) absorbers seen in low- and medium-resolution spectra obtained for the Quasar Absorption Line Key Project with the Hubble Space Telescope Faint Object Spectrograph (HST/FOS). For most of the C IV and Lyman-limit systems, observations in the optical wavelength range of the expected associated Mg II absorption are available. As at high redshift (z approximately 2), there are two subclasses of absorbers which are characterized by the presence or absence of MG II absorption. However, some low-redshift Mg II and Fe absorptions originate from regions optically thin to UV ionizing photons and thus, at low redshift, the low-ionization systems do not always trace high opacities, as is the case at high redshift. This implies that the mean ionization state of metal-rich, optically thin absorbing clouds falls with decreasing redshift, which is consistent with the hypothesis that the gas is photoionized by the metagalactic UV background radiation field. Two main constraints are derived from the analysis of the Lyman-limit sample, assuming photoionization models are valid. First, a low opacity to ionizing photons (tau(sub LL) approximately less than 1), as observed for several Mg II-Fe II systems at z approximately 0.5, sets limits on the ionization level of hydrogen, thus on the total hydrogen column density and the heavy element abundances, (Z/H) approximately -0.5 to -0.3. Second, the dimensions of individual Mg II clouds are smaller than at high redshift by a factor 3-10. At z approximately greater than 0.6, the O VI absorption doublet is detected in four of the five z(sub abs) much less than z(sub em) systems for which the O VI wavelength range has been observed, whereas the associated N V doublet is detected in only two cases. This suggests that the presence of a high-ionization O VI phase is a general property of z approximately 0.6-1 absorption systems

  4. Hubble Space Telescope Proper Motion (HSTPROMO) Catalogs of Galactic Globular Clusters. IV. Kinematic Profiles and Average Masses of Blue Straggler Stars

    Science.gov (United States)

    Baldwin, A. T.; Watkins, L. L.; van der Marel, R. P.; Bianchini, P.; Bellini, A.; Anderson, J.

    2016-08-01

    We make use of the Hubble Space Telescope proper-motion catalogs derived by Bellini et al. to produce the first radial velocity dispersion profiles σ (R) for blue straggler stars (BSSs) in Galactic globular clusters (GCs), as well as the first dynamical estimates for the average mass of the entire BSS population. We show that BSSs typically have lower velocity dispersions than stars with mass equal to the main-sequence turnoff mass, as one would expect for a more massive population of stars. Since GCs are expected to experience some degree of energy equipartition, we use the relation σ \\propto {M}-η , where η is related to the degree of energy equipartition, along with our velocity dispersion profiles to estimate BSS masses. We estimate η as a function of cluster relaxation from recent Monte Carlo cluster simulations by Bianchini et al. and then derive an average mass ratio {M}{BSS}/{M}{MSTO}=1.50+/- 0.14 and an average mass {M}{BSS}=1.22+/- 0.12 M ⊙ from 598 BSSs across 19 GCs. The final error bars include any systematic errors that are random between different clusters, but not any potential biases inherent to our methodology. Our results are in good agreement with the average mass of {M}{BSS}=1.22+/- 0.06 M ⊙ for the 35 BSSs in Galactic GCs in the literature with properties that have allowed individual mass determination. Based on proprietary and archival observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.

  5. The Hubble Space Telescope Cluster Supernova Survey. III. Correlated Properties of Type Ia Supernovae and Their Hosts at 0.9 < Z < 1.46

    Science.gov (United States)

    Meyers, J.; Aldering, G.; Barbary, K.; Barrientos, L. F.; Brodwin, M.; Dawson, K. S.; Deustua, S.; Doi, M.; Eisenhardt, P.; Faccioli, L.; Fakhouri, H. K.; Fruchter, A. S.; Gilbank, D. G.; Gladders, M. D.; Goldhaber, G.; Gonzalez, A. H.; Hattori, T.; Hsiao, E.; Ihara, Y.; Kashikawa, N.; Koester, B.; Konishi, K.; Lidman, C.; Lubin, L.; Morokuma, T.; Oda, T.; Perlmutter, S.; Postman, M.; Ripoche, P.; Rosati, P.; Rubin, D.; Rykoff, E.; Spadafora, A.; Stanford, S. A.; Suzuki, N.; Takanashi, N.; Tokita, K.; Yasuda, N.; Supernova Cosmology Project, The

    2012-05-01

    Using the sample of Type Ia supernovae (SNe Ia) discovered by the Hubble Space Telescope (HST) Cluster Supernova Survey and augmented with HST-observed SNe Ia in the Great Observatories Origins Deep Survey (GOODS) fields, we search for correlations between the properties of SNe and their host galaxies at high redshift. We use galaxy color and quantitative morphology to determine the red sequence in 25 clusters and develop a model to distinguish passively evolving early-type galaxies from star-forming galaxies in both clusters and the field. With this approach, we identify 6 SN Ia hosts that are early-type cluster members and 11 SN Ia hosts that are early-type field galaxies. We confirm for the first time at z > 0.9 that SNe Ia hosted by early-type galaxies brighten and fade more quickly than SNe Ia hosted by late-type galaxies. We also show that the two samples of hosts produce SNe Ia with similar color distributions. The relatively simple spectral energy distributions expected for passive galaxies enable us to measure stellar masses of early-type SN hosts. In combination with stellar mass estimates of late-type GOODS SN hosts from Thomson & Chary, we investigate the correlation of host mass with Hubble residual observed at lower redshifts. Although the sample is small and the uncertainties are large, a hint of this relation is found at z > 0.9. By simultaneously fitting the average cluster galaxy formation history and dust content to the red-sequence scatters, we show that the reddening of early-type cluster SN hosts is likely E(B - V) candles than other SNe Ia. Based on observations made with the NASA/ESA Hubble Space Telescope and obtained from the data archive at the Space Telescope Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under the NASA contract NAS 5-26555. The observations are associated with program 10496.

  6. Telescope simulators for Hubble - An overview of optical designs

    Science.gov (United States)

    Davilla, Pam; Wood, H. J.; Atcheson, Paul D.; Saunders, Renee; Sullivan, Joe; Vaughan, Arthur H.; Saisse, Michel

    1993-01-01

    This paper briefly describes optical design of the Hubble Space Telescope (HST) and overviews three optical design simulators for HST which have been proposed for use as verification tools to characterize the performance of second-generation instruments during ground testing. These simulators are: the Refractive Aberrated Simulator developed at Ball Aerospace, the Optical Simulator developed at Laboratoire Astronomie Spatiale, and the Jet Propulsion Laboratory Stimulus. Relative advantages and disadvantages of each optical configuration are discussed.

  7. FIRST ULTRAVIOLET REFLECTANCE SPECTRA OF PLUTO AND CHARON BY THE HUBBLE SPACE TELESCOPE COSMIC ORIGINS SPECTROGRAPH: DETECTION OF ABSORPTION FEATURES AND EVIDENCE FOR TEMPORAL CHANGE

    Energy Technology Data Exchange (ETDEWEB)

    Stern, S. A.; Spencer, J. R.; Shinn, A. [Southwest Research Institute, 1050 Walnut Street, Boulder, CO 80302 (United States); Cunningham, N. J.; Hain, M. J., E-mail: astern@swri.edu [Nebraska Wesleyan University, 5000 Saint Paul Avenue, Lincoln, NE 68504 (United States)

    2012-01-15

    We have observed the mid-UV spectra of both Pluto and its large satellite, Charon, at two rotational epochs using the Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) in 2010. These are the first HST/COS measurements of Pluto and Charon. Here we describe the observations and our reduction of them, and present the albedo spectra, average mid-UV albedos, and albedo slopes we derive from these data. These data reveal evidence for a strong absorption feature in the mid-UV spectrum of Pluto; evidence for temporal change in Pluto's spectrum since the 1990s is reported, and indirect evidence for a near-UV spectral absorption on Charon is also reported.

  8. Spectroscopy from the Hubble Space Telescope Cosmic Origins Spectrograph of the Southern Nova-like BB Doradus in an Intermediate State

    Science.gov (United States)

    Godon, Patrick; Sion, Edward M.; Gänsicke, Boris T.; Hubeny, Ivan; de Martino, Domitilla; Pala, Anna F.; Rodríguez-Gil, Pablo; Szkody, Paula; Toloza, Odette

    2016-12-01

    We present a spectral analysis of the spectrum from the Hubble Space Telescope Cosmic Origins Spectrograph (HST/COS) of the southern VY Scl nova-like variable BB Doradus, obtained as part of a Cycle 20 HST/COS survey of accreting white dwarfs (WDs) in cataclysmic variables. BB Dor was observed with COS during an intermediate state with a low mass accretion rate, thereby allowing an estimate of the WD temperature. The results of our spectral analysis show that the WD is a significant far-ultraviolet (FUV) component of the spectrum with a temperature of about 35,000-50,000 K, assuming a WD mass of 0.80 {M}⊙ ({log}(g)=8.4). The disk, with a mass accretion rate of ≈ {10}-10 {M}⊙ {{yr}}-1, contributes about 1/5 to 1/2 of the FUV flux.

  9. Legacy ExtraGalactic UV Survey with The Hubble Space Telescope: Stellar Cluster Catalogs and First Insights Into Cluster Formation and Evolution in NGC 628

    Science.gov (United States)

    Adamo, A.; Ryon, J. E.; Messa, M.; Kim, H.; Grasha, K.; Cook, D. O.; Calzetti, D.; Lee, J. C.; Whitmore, B. C.; Elmegreen, B. G.; Ubeda, L.; Smith, L. J.; Bright, S. N.; Runnholm, A.; Andrews, J. E.; Fumagalli, M.; Gouliermis, D. A.; Kahre, L.; Nair, P.; Thilker, D.; Walterbos, R.; Wofford, A.; Aloisi, A.; Ashworth, G.; Brown, T. M.; Chandar, R.; Christian, C.; Cignoni, M.; Clayton, G. C.; Dale, D. A.; de Mink, S. E.; Dobbs, C.; Elmegreen, D. M.; Evans, A. S.; Gallagher, J. S., III; Grebel, E. K.; Herrero, A.; Hunter, D. A.; Johnson, K. E.; Kennicutt, R. C.; Krumholz, M. R.; Lennon, D.; Levay, K.; Martin, C.; Nota, A.; Östlin, G.; Pellerin, A.; Prieto, J.; Regan, M. W.; Sabbi, E.; Sacchi, E.; Schaerer, D.; Schiminovich, D.; Shabani, F.; Tosi, M.; Van Dyk, S. D.; Zackrisson, E.

    2017-06-01

    We report the large effort that is producing comprehensive high-level young star cluster (YSC) catalogs for a significant fraction of galaxies observed with the Legacy ExtraGalactic UV Survey (LEGUS) Hubble treasury program. We present the methodology developed to extract cluster positions, verify their genuine nature, produce multiband photometry (from NUV to NIR), and derive their physical properties via spectral energy distribution fitting analyses. We use the nearby spiral galaxy NGC 628 as a test case for demonstrating the impact that LEGUS will have on our understanding of the formation and evolution of YSCs and compact stellar associations within their host galaxy. Our analysis of the cluster luminosity function from the UV to the NIR finds a steepening at the bright end and at all wavelengths suggesting a dearth of luminous clusters. The cluster mass function of NGC 628 is consistent with a power-law distribution of slopes ˜ -2 and a truncation of a few times 105 {M}⊙ . After their formation, YSCs and compact associations follow different evolutionary paths. YSCs survive for a longer time frame, confirming their being potentially bound systems. Associations disappear on timescales comparable to hierarchically organized star-forming regions, suggesting that they are expanding systems. We find mass-independent cluster disruption in the inner region of NGC 628, while in the outer part of the galaxy there is little or no disruption. We observe faster disruption rates for low mass (≤104 {M}⊙ ) clusters, suggesting that a mass-dependent component is necessary to fully describe the YSC disruption process in NGC 628. Based on observations obtained with the NASA/ESA Hubble Space Telescope, at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  10. Parallax of Galactic Cepheids from Spatially Scanning the Wide Field Camera 3 on the Hubble Space Telescope: The Case of SS Canis Majoris

    CERN Document Server

    Casertano, Stefano; Anderson, Richard I; Bowers, J Bradley; Clubb, Kelsey I; Cukierman, Aviv R; Filippenko, Alexei V; Graham, Melissa L; MacKenty, John W; Melis, Carl; Tucker, Brad E; Upadhya, Gautam

    2016-01-01

    We present a high-precision measurement of the parallax for the 12-day Cepheid SS Canis Majoris, obtained via spatial scanning with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). Spatial scanning enables astrometric measurements with a precision of 20-40 muas, an order of magnitude better than pointed observations. SS CMa is the second Cepheid targeted for parallax measurement with HST, and is the first of a sample of eighteen long-period >~ 10 days) Cepheids selected in order to improve the calibration of their period-luminosity relation and eventually permit a determination of the Hubble constant H_0 to better than 2%. The parallax of SS CMa is found to be 348 +/- 38 muas, corresponding to a distance of 2.9 +/- 0.3 kpc. We also present a refinement of the static geometric distortion of WFC3 obtained using spatial scanning observations of calibration fields, with a typical magnitude <~0.01 pixels on scales of 100 pixels.

  11. No Neon, but Jets in the Remarkable Recurrent Nova M31N 2008-12a?—Hubble Space Telescope Spectroscopy of the 2015 Eruption

    Science.gov (United States)

    Darnley, M. J.; Hounsell, R.; Godon, P.; Perley, D. A.; Henze, M.; Kuin, N. P. M.; Williams, B. F.; Williams, S. C.; Bode, M. F.; Harman, D. J.; Hornoch, K.; Link, M.; Ness, J.-U.; Ribeiro, V. A. R. M.; Sion, E. M.; Shafter, A. W.; Shara, M. M.

    2017-09-01

    The 2008 discovery of an eruption of M31N 2008-12a began a journey on which the true nature of this remarkable recurrent nova continues to be revealed. M31N 2008-12a contains a white dwarf (WD) close to the Chandrasekhar limit, accreting at a high rate from its companion, and undergoes thermonuclear eruptions that are observed yearly and may even be twice as frequent. In this paper, we report on Hubble Space Telescope Space Telescope Imaging Spectrograph ultraviolet spectroscopy taken within days of the predicted 2015 eruption, coupled with Keck spectroscopy of the 2013 eruption. Together, this spectroscopy permits the reddening to be constrained to E(B-V)=0.10+/- 0.03. The UV spectroscopy reveals evidence for highly ionized, structured, and high-velocity ejecta at early times. No evidence for neon is seen in these spectra, however, but it may be that little insight can be gained regarding the composition of the WD (CO versus ONe).

  12. Hubble Space Telescope far-ultraviolet imaging of the jet in 3C273: a common emission component from optical to X-rays

    CERN Document Server

    Jester, Sebastian; Martel, Andre'; Perlman, Eric; Sparks, Bill

    2007-01-01

    We present far-ultraviolet (UV) observations at 150 nm of the jet of the quasar 3C 273 obtained with the Advanced Camera for Survey's Solar Blind Channel (ACS/SBC) on board the Hubble Space Telescope. While the jet morphology is very similar to that in the optical and near-ultraviolet, the spectral energy distributions (SEDs) of the jet's sub-regions show an upturn in nu f_nu at 150 nm compared to 300 nm everywhere in the jet. Moreover, the 150 nm flux is compatible with extrapolating the X-ray power-law down to the ultra-violet region. This constitutes strong support for a common origin of the jet's far-UV and X-ray emission. It implies that even a substantial fraction of the *visible light* in the X-ray brightest parts of the jet arises from the same spectral component as the X-rays, as had been suggested earlier based on Spitzer Space Telescope observations. We argue that the identification of this UV/X-ray component opens up the possibility to establish the synchrotron origin of the X-ray emission by opti...

  13. Hubble Space Telescope Transmission Spectroscopy of the Exoplanet HD 189733b: High-altitude atmospheric haze in the optical and near-UV with STIS

    CERN Document Server

    Sing, D K; Aigrain, S; Charbonneau, D; Desert, J -M; Gibson, N; Gilliland, R; Hayek, W; Henry, G; Knutson, H; Etangs, A Lecavelier des; Mazeh, T; Tal-Or, L

    2011-01-01

    We present Hubble Space Telescope optical and near-ultraviolet transmission spectra of the transiting hot-Jupiter HD189733b, taken with the repaired Space Telescope Imaging Spectrograph (STIS) instrument. The resulting spectra cover the range 2900-5700 Ang and reach per-exposure signal-to-noise levels greater than 11,000 within a 500 Ang bandwidth. We used time series spectra obtained during two transit events to determine the wavelength dependance of the planetary radius and measure the exoplanet's atmospheric transmission spectrum for the first time over this wavelength range. Our measurements, in conjunction with existing HST spectra, now provides a broadband transmission spectrum covering the full optical regime. We find a planetary transmission spectrum in good agreement with that of Rayleigh scattering from a high-altitude atmospheric haze as previously found from HST ACS camera. The STIS data also shows unambiguous evidence of a large occulted stellar spot during one of our transit events, which we use...

  14. VERTICAL ATMOSPHERIC STRUCTURE IN A VARIABLE BROWN DWARF: PRESSURE-DEPENDENT PHASE SHIFTS IN SIMULTANEOUS HUBBLE SPACE TELESCOPE-SPITZER LIGHT CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Buenzli, Esther; Apai, Daniel; Flateau, Davin [Department of Astronomy and Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Morley, Caroline V. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, Santa Cruz, CA 95060 (United States); Showman, Adam P.; Lewis, Nikole K. [Department of Planetary Sciences and Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721 (United States); Burrows, Adam [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Marley, Mark S. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Reid, I. Neill, E-mail: ebuenzli@email.arizona.edu [Space Telescope Science Institute, Baltimore, MD 21218 (United States)

    2012-12-01

    Heterogeneous clouds or temperature perturbations in rotating brown dwarfs produce variability in the observed flux. We report time-resolved simultaneous observations of the variable T6.5 brown dwarf 2MASS J22282889-431026 over the wavelength ranges 1.1-1.7 {mu}m and broadband 4.5 {mu}m. Spectroscopic observations were taken with Wide Field Camera 3 on board the Hubble Space Telescope and photometry with the Spitzer Space Telescope. The object shows sinusoidal infrared variability with a period of 1.4 hr at most wavelengths with peak-to-peak amplitudes between 1.45% and 5.3% of the mean flux. While the light curve shapes are similar at all wavelengths, their phases differ from wavelength to wavelength with a maximum difference of more than half of a rotational period. We compare the spectra with atmospheric models of different cloud prescriptions, from which we determine the pressure levels probed at different wavelengths. We find that the phase lag increases with decreasing pressure level, or higher altitude. We discuss a number of plausible scenarios that could cause this trend of light curve phase with probed pressure level. These observations are the first to probe heterogeneity in an ultracool atmosphere in both horizontal and vertical directions, and thus are an ideal test case for realistic three-dimensional simulations of the atmospheric structure with clouds in brown dwarfs and extrasolar planets.

  15. Interferometric Astrometry of the Low-Mass Binary GL 791.2 (= HU Del) UsingHubble Space Telescope Fine Guidance Sensor 3: Parallax and Component Masses

    Science.gov (United States)

    Benedict, G. Fritz; McArthur, Barbara E.; Franz, Otto G.; Wasserman, Lawrence H.; Henry, Todd J.

    2000-08-01

    With fourteen epochs of fringe-tracking data spanning 1.7 yr from Fine Guidance Sensor 3 we have obtained a parallax (πabs=113.1+/-0.3 mas) and perturbation orbit for Gl 791.2A. Contemporaneous fringe-scanning observations yield only three clear detections of the secondary on both interferometer axes. They provide a mean component magnitude difference, ΔV=3.27+/-0.10. The period (P=1.4731 yr), from the perturbation orbit, and the semimajor axis (a=0.963+/-0.007 AU), from the measured component separations with our parallax, provide a total system mass MA+MB=0.412+/-0.009 Msolar. Component masses are MA=0.286+/-0.006 Msolar and MB=0.126+/-0.003 Msolar. Gl 791.2A and Gl 791.2B are placed in a sparsely populated region of the lower main-sequence mass-luminosity relation where they help define the relation because the masses have been determined to high accuracy, with errors of only 2%. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

  16. Associated Absorption Lines in the Radio-Loud Quasar 3C 351 Far-Ultraviolet Echelle Spectroscopy from the Hubble Space Telescope

    CERN Document Server

    Yuan, Q; Brotherton, M; Tripp, T M; Kaiser, M E; Kriss, G A

    2002-01-01

    As one of the most luminous radio-loud quasars showing intrinsic ultraviolet (UV) and X-ray absorption, 3C 351 provides a laboratory for studying the kinematics and physical conditions of such ionized absorbers. We present an analysis of the intrinsic absorption lines in the high-resolution ($\\sim$ 7 km/s) far-UV spectrum which was obtained from observations with the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST). The spectrum spans wavelengths from 1150 \\AA to 1710 \\AA, and shows strong emission lines from O VI and Ly$\\alpha$. Associated absorption lines are present on the blue wings of the high-ionization emission doublets O VI $\\lambda\\lambda$ 1032,1038 and N V $\\lambda\\lambda$ 1238,1242, as well as the Lyman lines through Ly$\\epsilon$. These intrinsic absorption features are resolved into several distinct kinematic components, covering rest-frame velocities from -40 to -2800 km/s, with respect to the systemic redshift of $z_{em}=0.3721$. For the majority of these abs...

  17. The Globular Cluster System of the Coma cD Galaxy NGC 4874 from Hubble Space Telescope ACS and WFC3/IR Imaging

    Science.gov (United States)

    Cho, Hyejeon; Blakeslee, John P.; Chies-Santos, Ana L.; Jee, M. James; Jensen, Joseph B.; Peng, Eric W.; Lee, Young-Wook

    2016-05-01

    We present new Hubble Space Telescope (HST) optical and near-infrared (NIR) photometry of the rich globular cluster (GC) system NGC 4874, the cD galaxy in the core of the Coma cluster (Abell 1656). NGC 4874 was observed with the HST Advanced Camera for Surveys in the F475W (g 475) and F814W (I 814) passbands and with the Wide Field Camera 3 IR Channel in F160W (H 160). The GCs in this field exhibit a bimodal optical color distribution with more than half of the GCs falling on the red side at g 475-I 814 > 1. Bimodality is also present, though less conspicuously, in the optical-NIR I 814-H 160 color. Consistent with past work, we find evidence for nonlinearity in the g 475-I 814 versus I 814-H 160 color-color relation. Our results thus underscore the need for understanding the detailed form of the color-metallicity relations in interpreting observational data on GC bimodality. We also find a very strong color-magnitude trend, or “blue tilt,” for the blue component of the optical color distribution of the NGC 4874 GC system. A similarly strong trend is present for the overall mean I 814-H 160 color as a function of magnitude; for M 814 law and becomes much weaker at lower masses. As in other similar systems, the spatial distribution of the blue GCs is more extended than that of the red GCs, partly because of blue GCs associated with surrounding cluster galaxies. In addition, the center of the GC system is displaced by 4 ± 1 kpc toward the southwest from the luminosity center of NGC 4874, in the direction of NGC 4872. Finally, we remark on a dwarf elliptical galaxy with a noticeably asymmetrical GC distribution. Interestingly, this dwarf has a velocity of nearly -3000 km s-1 with respect to NGC 4874; we suggest it is on its first infall into the cluster core and is undergoing stripping of its GC system by the cluster potential. Based on observations with the NASA/ESA Hubble Space Telescope, obtained from the Space Telescope Science Institute (STScI), which is

  18. Resolving the Shocks in Radio Galaxy Nebulae: Hubble Space Telescope and Radio Imaging of 3C 171, 3C 277.3, and PKS 2250-41

    Science.gov (United States)

    Tilak, Avanti; O'Dea, Christopher P.; Tadhunter, Clive; Wills, Karen; Morganti, Raffaella; Baum, Stefi A.; Koekemoer, Anton M.; Dallacasa, Daniele

    2005-12-01

    We present the results of Hubble Space Telescope (HST) WFPC2 medium-band and narrowband imaging and Very Large Array and MERLIN2 radio imaging of three powerful radio galaxies: 3C 171, 3C 277.3, and PKS 2250-41. We obtained images of the rest frame [O III] λ5007 and [O II] λ3727 line emission using the linear ramp filters on WFPC2. The correlations of the emission-line morphology and the [O III]/[O II] line ratios with the radio emission seen in ground-based observations are clarified by the HST imaging. We confirm that the radio lobes and hot spots are preferentially associated with lower ionization gas. The galaxy 3C 171 exhibits high surface brightness emission-line gas mainly along the radio source axis. The lowest ionization gas is seen at the eastern hot spot. In 3C 277.3 there is bright high-ionization gas (and continuum) offset just to the east of the radio knot K1. Our observations are consistent with previous work suggesting that this emission is produced by precursor gas ionized by the shock being driven into the cloud by the deflected radio jet. In PKS 2250-41 we resolve the emission-line arc that wraps around the outer rim of the western lobe. The lower ionization [O II] emission is nested just interior to the higher ionization [O III] emission, suggesting that we have resolved the cooling region behind the bow shock. We also detect possible continuum emission from the secondary hot spot. Thus, our observations support the hypothesis that in these sources the interaction between the expanding radio source and the ambient gas strongly influences the morphology, kinematics, and ionization of the gas. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. These observations are associated with program 6657 (principal investigator C. Tadhunter).

  19. MC2: Mapping the Dark Matter Distribution of the "Toothbrush" Cluster RX J0603.3+4214 with Hubble Space Telescope and Subaru Weak Lensing

    Science.gov (United States)

    Jee, M. James; Dawson, William A.; Stroe, Andra; Wittman, David; van Weeren, Reinout J.; Brüggen, Marcus; Bradač, Maruša; Röttgering, Huub

    2016-02-01

    The galaxy cluster RX J0603.3+4214 at z = 0.225 is one of the rarest clusters boasting an extremely large (˜2 Mpc) radio relic. Because of the remarkable morphology of the relic, the cluster is nicknamed the “Toothbrush Cluster.” Although the cluster's underlying mass distribution is one of the critical pieces of information needed to reconstruct the merger scenario responsible for the puzzling radio relic morphology, its proximity to the Galactic plane b ˜ 10° has imposed significant observational challenges. We present a high-resolution weak-lensing study of the cluster with Subaru/Suprime Cam and Hubble Space Telescope imaging data. Our mass reconstruction reveals that the cluster is composed of complicated dark matter substructures closely tracing the galaxy distribution, in contrast, however, with the relatively simple binary X-ray morphology. Nevertheless, we find that the cluster mass is still dominated by the two most massive clumps aligned north-south with a ˜3:1 mass ratio ({M}200={6.29}-1.62+2.24× {10}14 {M}⊙ and {1.98}-0.74+1.24× {10}14 {M}⊙ for the northern and southern clumps, respectively). The southern mass peak is ˜2‧ offset toward the south with respect to the corresponding X-ray peak, which has a “bullet”-like morphology pointing south. Comparison of the current weak-lensing result with the X-ray, galaxy, and radio relic suggests that perhaps the dominant mechanism responsible for the observed relic may be a high-speed collision of the two most massive subclusters, although the peculiarity of the morphology necessitates involvement of additional subclusters. Careful numerical simulations should follow in order to obtain more complete understanding of the merger scenario utilizing all existing observations. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc.

  20. Ultra-Deep Hubble Space Telescope Imaging of the Small Magellanic Cloud: The Initial Mass Function of Stars with M <~ 1 M ⊙

    Science.gov (United States)

    Kalirai, Jason S.; Anderson, Jay; Dotter, Aaron; Richer, Harvey B.; Fahlman, Gregory G.; Hansen, Brad M. S.; Hurley, Jarrod; Reid, I. Neill; Rich, R. Michael; Shara, Michael M.

    2013-02-01

    We present a new measurement of the stellar initial mass function (IMF) based on ultra-deep, high-resolution photometry of >5000 stars in the outskirts of the Small Magellanic Cloud (SMC) galaxy. The Hubble Space Telescope (HST) Advanced Camera for Surveys observations reveal this rich, cospatial population behind the foreground globular cluster 47 Tuc, which we targeted for 121 HST orbits. The stellar main sequence of the SMC is measured in the F606W, F814W color-magnitude diagram down to ~30th magnitude, and is cleanly separated from the foreground star cluster population using proper motions. We simulate the SMC population by extracting stellar masses (single and unresolved binaries) from specific IMFs and converting those masses to luminosities in our bandpasses. The corresponding photometry for these simulated stars is drawn directly from a rich cloud of 4 million artificial stars, thereby accounting for the real photometric scatter and completeness of the data. Over a continuous and well-populated mass range of M = 0.37-0.93 M ⊙ (e.g., down to a ~75% completeness limit at F606W = 28.7), we demonstrate that the IMF is well represented by a single power-law form with slope α = -1.90 (+0.15 -0.10) (3σ error) (e.g., dN/dMvprop M α). This is shallower than the Salpeter slope of α = -2.35, which agrees with the observed stellar luminosity function at higher masses. Our results indicate that the IMF does not turn over to a more shallow power-law form within this mass range. We discuss implications of this result for the theory of star formation, the inferred masses of galaxies, and the (lack of a) variation of the IMF with metallicity. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. These observations are associated with proposal GO-11677.

  1. A Cluster Of Activities On Coma From The Hubble Space Telescope, StarDate, And McDonald Observatory

    Science.gov (United States)

    Hemenway, Mary Kay; Jogee, S.; Fricke, K.; Preston, S.

    2011-01-01

    With a goal of providing a vast audience of students, teachers, the general public, and Spanish-speakers with activities to learn about research on the Coma cluster of galaxies based on the HST ACS Treasury survey of Coma, McDonald Observatory used a many-faceted approach. Since this research offered an unprecedented legacy dataset, part of the challenge was to convey the importance of this project to a diverse audience. The methodology was to create different products for different (overlapping) audiences. Five radio programs were produced in English and Spanish for distribution on over 500 radio stations in the US and Mexico with a listening audience of over 2 million; in addition to the radio listeners, there were over 13,000 downloads of the English scripts and almost 6000 of the Spanish. Images were prepared for use in the StarDate Online Astronomy Picture of the Week, for ViewSpace (used in museums), and for the StarDate/Universo Teacher Guide. A high-school level activity on the Coma Cluster was prepared and distributed both on-line and in an upgraded printed version of the StarDate/Universo Teacher Guide. This guide has been distributed to over 1700 teachers nationally. A YouTube video about careers and research in astronomy using the Coma cluster as an example was produced. Just as the activities were varied, so were the evaluation methods. This material is based upon work supported by the National Aeronautics and Space Administration under Grant/Contract/Agreement No. HST-EO-10861.35-A issued through the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

  2. Near-Infrared Imaging of a z=6.42 Quasar Host Galaxy With the Hubble Space Telescope Wide Field Camera 3

    CERN Document Server

    Mechtley, Matt; Ryan, Russell E; Schneider, Glenn; Cohen, Seth H; Jansen, Rolf A; Fan, Xiaohui; Hathi, Nimish P; Keel, William C; Koekemoer, Anton M; Röttgering, Huub; Scannapieco, Evan; Schneider, Donald P; Strauss, Michael A; Yan, Haojing

    2012-01-01

    We report on deep near-infrared F125W (J) and F160W (H) Hubble Space Telescope Wide Field Camera 3 images of the z=6.42 quasar J1148+5251 to attempt to detect rest-frame near-ultraviolet emission from the host galaxy. These observations included contemporaneous observations of a nearby star of similar near-infrared colors to measure temporal variations in the telescope and instrument point spread function (PSF). We subtract the quasar point source using both this direct PSF and a model PSF. Using direct subtraction, we measure an upper limit for the quasar host galaxy of m_J>22.8, m_H>23.0 AB mag (2 sigma). After subtracting our best model PSF, we measure a limiting surface brightness from 0.3"-0.5" radius of mu_J > 23.5, mu_H > 23.7 AB magarc (2 sigma). We test the ability of the model subtraction method to recover the host galaxy flux by simulating host galaxies with varying integrated magnitude, effective radius, and S\\'ersic index, and conducting the same analysis. These models indicate that the surface b...

  3. Hubble Space Telescope Combined Strong and Weak Lensing Analysis of the CLASH Sample: Mass and Magnification Models and Systematic Uncertainties

    CERN Document Server

    Zitrin, Adi; Merten, Julian; Melchior, Peter; Meneghetti, Massimo; Koekemoer, Anton; Coe, Dan; Maturi, Matteo; Bartelmann, Matthias; Postman, Marc; Umetsu, Keiichi; Seidel, Gregor; Sendra, Irene; Broadhurst, Tom; Balestra, Italo; Biviano, Andrea; Grillo, Claudio; Mercurio, Amata; Nonino, Mario; Rosati, Piero; Bradley, Larry; Carrasco, Mauricio; Donahue, Megan; Ford, Holland; Frye, Brenda L; Moustakas, John

    2014-01-01

    [ABRIDGED] We present results from an HST lensing analysis of the complete Cluster Lensing And Supernova survey with Hubble (CLASH) cluster sample. We identify various new multiple-images previously undiscovered, allowing improved or first constraints on the cluster inner mass distributions and profiles. We combine these strong-lensing constraints with weak lensing shape measurements within the HST FOV to jointly constrain the mass distributions. The analysis is performed in two different common parameterizations (one adopts light-traces-mass for both galaxies and dark matter while the other adopts an analytical, elliptical NFW form for the dark matter), to provide a better assessment of the underlying systematics - which is most important for deep lensing surveys such as CLASH and the Hubble Frontier Fields, especially when studying high-redshift magnified objects. We find that the typical (median), relative systematic differences throughout the central FOV are $\\sim40\\%$ in the (dimensionless) mass density,...

  4. New Constraints on ΩM, ΩΛ, and w from an Independent Set of 11 High-Redshift Supernovae Observed with the Hubble Space Telescope

    Science.gov (United States)

    Knop, R. A.; Aldering, G.; Amanullah, R.; Astier, P.; Blanc, G.; Burns, M. S.; Conley, A.; Deustua, S. E.; Doi, M.; Ellis, R.; Fabbro, S.; Folatelli, G.; Fruchter, A. S.; Garavini, G.; Garmond, S.; Garton, K.; Gibbons, R.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hardin, D.; Hook, I.; Howell, D. A.; Kim, A. G.; Lee, B. C.; Lidman, C.; Mendez, J.; Nobili, S.; Nugent, P. E.; Pain, R.; Panagia, N.; Pennypacker, C. R.; Perlmutter, S.; Quimby, R.; Raux, J.; Regnault, N.; Ruiz-Lapuente, P.; Sainton, G.; Schaefer, B.; Schahmaneche, K.; Smith, E.; Spadafora, A. L.; Stanishev, V.; Sullivan, M.; Walton, N. A.; Wang, L.; Wood-Vasey, W. M.; Yasuda, N.

    2003-11-01

    We report measurements of ΩM, ΩΛ, and w from 11 supernovae (SNe) at z=0.36-0.86 with high-quality light curves measured using WFPC2 on the Hubble Space Telescope (HST). This is an independent set of high-redshift SNe that confirms previous SN evidence for an accelerating universe. The high-quality light curves available from photometry on WFPC2 make it possible for these 11 SNe alone to provide measurements of the cosmological parameters comparable in statistical weight to the previous results. Combined with earlier Supernova Cosmology Project data, the new SNe yield a measurement of the mass density ΩM=0.25+0.07-0.06(statistical)+/-0.04 (identified systematics), or equivalently, a cosmological constant of ΩΛ=0.75+0.06-0.07(statistical)+/-0.04 (identified systematics), under the assumptions of a flat universe and that the dark energy equation-of-state parameter has a constant value w=-1. When the SN results are combined with independent flat-universe measurements of ΩM from cosmic microwave background and galaxy redshift distortion data, they provide a measurement of w=-1.05+0.15-0.20(statistical)+/-0.09 (identified systematic), if w is assumed to be constant in time. In addition to high-precision light-curve measurements, the new data offer greatly improved color measurements of the high-redshift SNe and hence improved host galaxy extinction estimates. These extinction measurements show no anomalous negative E(B-V) at high redshift. The precision of the measurements is such that it is possible to perform a host galaxy extinction correction directly for individual SNe without any assumptions or priors on the parent E(B-V) distribution. Our cosmological fits using full extinction corrections confirm that dark energy is required with P(ΩΛ>0)>0.99, a result consistent with previous and current SN analyses that rely on the identification of a low-extinction subset or prior assumptions concerning the intrinsic extinction distribution. Based in part on

  5. Hubble Space Telescope Proper Motion (HSTPROMO) Catalogs of Galactic Globular Clusters. V. The Rapid Rotation of 47 Tuc Traced and Modeled in Three Dimensions

    Science.gov (United States)

    Bellini, A.; Bianchini, P.; Varri, A. L.; Anderson, J.; Piotto, G.; van der Marel, R. P.; Vesperini, E.; Watkins, L. L.

    2017-08-01

    High-precision proper motions of the globular cluster 47 Tuc have allowed us to measure for the first time the cluster rotation in the plane of the sky and the velocity anisotropy profile from the cluster core out to about 13‧. These profiles are coupled with prior measurements along the line of sight (LOS) and the surface brightness profile and fit all together with self-consistent models specifically constructed to describe quasi-relaxed stellar systems with realistic differential rotation, axisymmetry, and pressure anisotropy. The best-fit model provides an inclination angle i between the rotation axis and the LOS direction of 30° and is able to simultaneously reproduce the full three-dimensional kinematics and structure of the cluster, while preserving a good agreement with the projected morphology. Literature models based solely on LOS measurements imply a significantly different inclination angle (i = 45°), demonstrating that proper motions play a key role in constraining the intrinsic structure of 47 Tuc. Our best-fit global dynamical model implies an internal rotation higher than previous studies have shown and suggests a peak of the intrinsic V/σ ratio of ∼0.9 at around two half-light radii, with a nonmonotonic intrinsic ellipticity profile reaching values up to 0.45. Our study unveils a new degree of dynamical complexity in 47 Tuc, which may be leveraged to provide new insights into the formation and evolution of globular clusters. Based on archival observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.

  6. Hubble Space Telescope Observations of Sub-Damped Lyman-alpha Absorbers at z < 0.5, and Implications for Galaxy Chemical Evolution

    CERN Document Server

    Som, Debopam; Meiring, Joseph; York, Donald G; Péroux, Celine; Lauroesch, James T; Aller, Monique C; Khare, Pushpa

    2015-01-01

    We report observations of four sub-damped Lyman-alpha (sub-DLA) quasar absorbers at z<0.5 obtained with the Hubble Space Telescope Cosmic Origins Spectrograph. We measure the available neutrals or ions of C, N, O, Si, P, S, Ar, Mn, Fe, and/or Ni. Our data have doubled the sub-DLA metallicity samples at z<0.5 and improved constraints on sub-DLA chemical evolution. All four of our sub-DLAs are consistent with near-solar or super-solar metallicities and relatively modest ionization corrections; observations of more lines and detailed modeling will help to verify this. Combining our data with measurements from the literature, we confirm previous suggestions that the N(HI)-weighted mean metallicity of sub-DLAs exceeds that of DLAs at all redshifts studied, even after making ionization corrections for sub-DLAs. The absorber toward PHL 1598 shows significant dust depletion. The absorbers toward PHL 1226 and PKS 0439-433 show the S/P ratio consistent with solar, i.e., they lack a profound odd-even effect. The a...

  7. The Hubble Space Telescope UV Legacy Survey of galactic globular clusters. VI. The internal kinematics of the multiple stellar populations in NGC 2808

    CERN Document Server

    Bellini, A; Piotto, G; Milone, A P; Hong, J; Anderson, J; van der Marel, R P; Bedin, L R; Cassisi, S; D'Antona, F; Marino, A F; Renzini, A

    2015-01-01

    Numerous observational studies have revealed the ubiquitous presence of multiple stellar populations in globular clusters and cast many hard challenges for the study of the formation and dynamical history of these stellar systems. In this Letter we present the results of a study of the kinematic properties of multiple populations in NGC 2808 based on high-precision Hubble Space Telescope proper-motion measurements. In a recent study, Milone et al. have identified five distinct populations (A, B, C, D, and E) in NGC 2808. Populations D and E coincide with the helium-enhanced populations in the middle and the blue main sequences (mMS and bMS) previously discovered by Piotto et al.; populations A, B, and C correspond to the redder main sequence (rMS) that in the Piotto et al. was associated with the primordial stellar population. Our analysis shows that, in the outermost regions probed (between about 1.5 and 2 times the cluster half-light radius), the velocity distribution of populations D and E is radially anis...

  8. The Structure of Nuclear Star Clusters in Nearby Late-type Spiral Galaxies from Hubble Space Telescope Wide Field Camera 3 Imaging

    CERN Document Server

    Carson, Daniel J; Seth, Anil C; Brok, Mark den; Cappelari, Michele; Greene, Jenny E; Ho, Luis C; Neumayer, Nadine

    2015-01-01

    We obtained Hubble Space Telescope/Wide Field Camera 3 imaging of a sample of ten of the nearest and brightest nuclear clusters residing in late-type spiral galaxies, in seven bands that span the near-ultraviolet to the near-infrared. Structural properties of the clusters were measured by fitting two-dimensional surface brightness profiles to the images using GALFIT. The clusters exhibit a wide range of structural properties. For six of the ten clusters in our sample, we find changes in the effective radius with wavelength, suggesting radially varying stellar populations. In four of the objects, the effective radius increases with wavelength, indicating the presence of a younger population which is more concentrated than the bulk of the stars in the cluster. However, we find a general decrease in effective radius with wavelength in two of the objects in our sample, which may indicate extended, circumnuclear star formation. We also find a general trend of increasing roundness of the clusters at longer waveleng...

  9. The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. VII. Implications from the Nearly Universal Nature of Horizontal Branch Discontinuities

    CERN Document Server

    Brown, Thomas M; D'Antona, Francesca; Salaris, Maurizio; Milone, Antonino P; Dalessandro, Emanuele; Piotto, Giampaolo; Renzini, Alvio; Sweigart, Allen V; Bellini, Andrea; Ortolani, Sergio; Sarajedini, Ata; Aparicio, Antonio; Bedin, Luigi R; Anderson, Jay; Pietrinferni, Adriano; Nardiello, Domenico

    2016-01-01

    The UV-initiative Hubble Space Telescope Treasury survey of Galactic globular clusters provides a new window into the phenomena that shape the morphological features of the horizontal branch (HB). Using this large and homogeneous catalog of UV and blue photometry, we demonstrate that the HB exhibits discontinuities that are remarkably consistent in color (effective temperature). This consistency is apparent even among some of the most massive clusters hosting multiple distinct sub-populations (such as NGC 2808, omega Cen, and NGC 6715), demonstrating that these phenomena are primarily driven by atmospheric physics that is independent of the underlying population properties. However, inconsistencies arise in the metal-rich clusters NGC 6388 and NGC 6441, where the discontinuity within the blue HB (BHB) distribution shifts ~1,000 K to 2,000 K hotter. We demonstrate that this shift is likely due to a large helium enhancement in the BHB stars of these clusters, which in turn affects the surface convection and evo...

  10. A Panchromatic Catalog of Early-type Galaxies at Intermediate Redshift in the Hubble Space Telescope Wide Field Camera 3 Early Release Science Field

    Science.gov (United States)

    Rutkowski, M. J.; Cohen, S. H.; Kaviraj, S.; O'Connell, R. W.; Hathi, N. P.; Windhorst, R. A.; Ryan, R. E., Jr.; Crockett, R. M.; Yan, H.; Kimble, R. A.; Silk, J.; McCarthy, P. J.; Koekemoer, A.; Balick, B.; Bond, H. E.; Calzetti, D.; Disney, M. J.; Dopita, M. A.; Frogel, J. A.; Hall, D. N. B.; Holtzman, J. A.; Paresce, F.; Saha, A.; Trauger, J. T.; Walker, A. R.; Whitmore, B. C.; Young, E. T.

    2012-03-01

    In the first of a series of forthcoming publications, we present a panchromatic catalog of 102 visually selected early-type galaxies (ETGs) from observations in the Early Release Science (ERS) program with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) of the Great Observatories Origins Deep Survey-South (GOODS-S) field. Our ETGs span a large redshift range, 0.35 lsim z lsim 1.5, with each redshift spectroscopically confirmed by previous published surveys of the ERS field. We combine our measured WFC3 ERS and Advanced Camera for Surveys (ACS) GOODS-S photometry to gain continuous sensitivity from the rest-frame far-UV to near-IR emission for each ETG. The superior spatial resolution of the HST over this panchromatic baseline allows us to classify the ETGs by their small-scale internal structures, as well as their local environment. By fitting stellar population spectral templates to the broadband photometry of the ETGs, we determine that the average masses of the ETGs are comparable to the characteristic stellar mass of massive galaxies, 1011 publications which address the diversity of stellar populations likely to be present in these ETGs, and the potential mechanisms by which recent star formation episodes are activated, are discussed.

  11. Hubble Space Telescope spectra of the type Ia supernova SN 2011fe: A low-energy delayed detonation of a white dwarf with Z

    CERN Document Server

    Mazzali, Paolo; Hachinger, Stephan; Ellis, Richard; Nugent, Peter E; Howell, D Andrew; Gal-Yam, Avishay; Maguire, Kate; Cooke, Jeff; Thomas, Rollin

    2013-01-01

    Hubble Space Telescope spectroscopic observations of the nearby type Ia supernova (SN Ia) SN 2011fe, taken on 10 epochs from -13.5 to +41 days relative to B-band maximum light, and spanning the far-ultraviolet (UV) to the near-infrared (IR) are presented. This spectroscopic coverage makes SN 2011fe the best-studied local SN Ia to date. SN 2011fe is a typical moderately-luminous SN Ia with no evidence for dust extinction. Its near-UV spectral properties are representative of a larger sample of local events studied in Maguire et al. (2012). As a result, conclusions inferred from our detailed investigations are likely representative of those for other normal SNe Ia. The near-UV to optical spectra of SN 2011fe are modelled with a Monte Carlo radiative transfer code using the technique of 'abundance tomography', providing tight constraints on the density structure and abundance stratification of the event. SN 2011fe was a relatively weak explosion, with moderate Fe-group yields. Although its density structure is c...

  12. HUBBLE SPACE TELESCOPE PRE-PERIHELION ACS/WFC IMAGING POLARIMETRY OF COMET ISON (C/2012 S1) AT 3.81 AU

    Energy Technology Data Exchange (ETDEWEB)

    Hines, Dean C.; Mutchler, Max; Hammer, Derek [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Videen, Gorden; Sitko, Michael L.; Yanamandra-Fisher, Padmavati A. [Space Science Institute, 4750 Walnut Street, Suite 205, Boulder, CO 80301 (United States); Zubko, Evgenij; Muinonen, Karri [Department of Physics, P.O. Box 64, FI-00014 University of Helsinki (Finland); Shkuratov, Yuriy; Kaydash, Vadim G. [Astronomical Institute of V. N. Karazin University, Kharkov, 61058 (Ukraine); Knight, Matthew M. [Lowell Observatory, Flagstaff, AZ 86001 (United States); Lisse, Carey M. [Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723 (United States)

    2014-01-10

    We present polarization images of Comet ISON (C/2012 S1) taken with the Hubble Space Telescope (HST) on UTC 2013 May 8 (r {sub h} = 3.81 AU, Δ = 4.34 AU), when the phase angle was α ≈ 12.°16. This phase angle is approximately centered in the negative polarization branch for cometary dust. The region beyond 1000 km (∼0.32 arcsec ≈ 6 pixels) from the nucleus shows a negative polarization amplitude of p% ∼ –1.6%. Within 1000 km of the nucleus, the polarization position angle rotates to be approximately perpendicular to the scattering plane, with an amplitude p% ∼ +2.5%. Such positive polarization has been observed previously as a characteristic feature of cometary jets, and we show that Comet ISON does indeed harbor a jet-like feature. These HST observations of Comet ISON represent the first visible light, imaging polarimetry with subarcsecond spatial resolution of a Nearly Isotropic Comet beyond 3.8 AU from the Sun at a small phase angle. The observations provide an early glimpse of the properties of the cometary dust preserved in this Oort-Cloud comet.

  13. Hubble Space Telescope Grism Spectroscopy of Extreme Starbursts Across Cosmic Time: The Role of Dwarf Galaxies in the Star Formation History of the Universe

    CERN Document Server

    Atek, Hakim; Pacifici, Camilla; Malkan, Matthew; Charlot, Stephane; Lee, Janice; Bedregal, Alejandro; Bunker, Andrew J; Colbert, James W; Dressler, Alan; Hathi, Nimish; Lehnert, Matthew; Martin, Crystal L; McCarthy, Patrick; Rafelski, Marc; Ross, Nathaniel; Siana, Brian; Teplitz, Harry I

    2014-01-01

    Near infrared slitless spectroscopy with the Wide Field Camera 3, onboard the Hubble Space Telescope, offers a unique opportunity to study low-mass galaxy populations at high-redshift ($z\\sim$1-2). While most high$-z$ surveys are biased towards massive galaxies, we are able to select sources via their emission lines that have very-faint continua. We investigate the star formation rate (SFR)-stellar mass ($M_{\\star}$) relation for about 1000 emission-line galaxies identified over a wide redshift range of $0.3 \\lesssim z \\lesssim 2.3$. We use the H$_{\\alpha}$ emission as an accurate SFR indicator and correct the broadband photometry for the strong nebular contribution to derive accurate stellar masses down to $M_{\\star} \\sim 10^{7} M_{\\odot}$. We focus here on a subsample of galaxies that show extremely strong emission lines (EELGs) with rest-frame equivalent widths ranging from 200 to 1500 \\AA. This population consists of outliers to the normal SFR-$M_{\\star}$ sequence with much higher specific SFRs ($> 10$ Gy...

  14. A High-Resolution Multiband Survey of Westerlund 2 With the Hubble Space Telescope I: Is the Massive Star Cluster Double?

    CERN Document Server

    Zeidler, Peter; Nota, Antonella; Grebel, Eva K; Tosi, Monica; Bonanos, Alceste Z; Pasquali, Anna; Christian, Carol; de Mink, Selma E; Ubeda, Leonardo

    2015-01-01

    We present first results from a high resolution multi-band survey of the Westerlund 2 region with the Hubble Space Telescope. Specifically, we imaged Westerlund 2 with the Advanced Camera for Surveys through the $F555W$, $F814W$, and $F658N$ filters and with the Wide Field Camera 3 in the $F125W$, $F160W$, and $F128N$ filters. We derive the first high resolution pixel-to-pixel map of the color excess $E(B-V)_g$ of the gas associated with the cluster, combining the H$\\alpha$ ($F658N$) and Pa$\\beta$ ($F128N$) line observations. We demonstrate that, as expected, the region is affected by significant differential reddening with a median of $E(B-V)_g=1.87$~mag. After separating the populations of cluster members and foreground contaminants using a $(F814W-F160W)$ vs. $F814W$ color-magnitude diagram, we identify a pronounced pre-main-sequence population in Westerlund 2 showing a distinct turn-on. After dereddening each star of Westerlund 2 individually in the color-magnitude diagram we find via over-plotting PARSEC...

  15. HUBBLE SPACE TELESCOPE AND HI IMAGING OF STRONG RAM PRESSURE STRIPPING IN THE COMA SPIRAL NGC 4921: DENSE CLOUD DECOUPLING AND EVIDENCE FOR MAGNETIC BINDING IN THE ISM

    Energy Technology Data Exchange (ETDEWEB)

    Kenney, Jeffrey D. P.; Abramson, Anne [Yale University Astronomy Department, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Bravo-Alfaro, Hector, E-mail: jeff.kenney@yale.edu [Institut d’Astrophysique de Paris, CNRS/UPMC, 98bis, Boulevard Arago F-75014, Paris (France)

    2015-08-15

    Remarkable dust extinction features in the deep Hubble Space Telescope (HST) V and I images of the face-on Coma cluster spiral galaxy NGC 4921 show in unprecedented ways how ram pressure strips the ISM from the disk of a spiral galaxy. New VLA HI maps show a truncated and highly asymmetric HI disk with a compressed HI distribution in the NW, providing evidence for ram pressure acting from the NW. Where the HI distribution is truncated in the NW region, HST images show a well-defined, continuous front of dust that extends over 90° and 20 kpc. This dust front separates the dusty from dust-free regions of the galaxy, and we interpret it as galaxy ISM swept up near the leading side of the ICM–ISM interaction. We identify and characterize 100 pc–1 kpc scale substructure within this dust front caused by ram pressure, including head–tail filaments, C-shaped filaments, and long smooth dust fronts. The morphology of these features strongly suggests that dense gas clouds partially decouple from surrounding lower density gas during stripping, but decoupling is inhibited, possibly by magnetic fields that link and bind distant parts of the ISM.

  16. The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. X. The radial distribution of stellar populations in NGC 2808

    CERN Document Server

    Simioni, Matteo; Bedin, Luigi R; Aparicio, Antonio; Piotto, Giampaolo; Vesperini, Enrico; Hong, Jongsuk

    2016-01-01

    Due to their extreme helium abundance, the multiple stellar populations of the globular cluster NGC 2808 have been widely investigated from a photometric, spectroscopic, and kinematic perspective. The most striking feature of the color-magnitude diagram of NGC 2808 is the triple main sequence (MS), with the red MS corresponding to a stellar population with primordial helium, and the middle and the blue MS being enhanced in helium up to Y$\\sim$0.32 and $\\sim$0.38, respectively. A recent study has revealed that this massive cluster hosts at least five distinct stellar populations (A, B, C, D, and E). Among them populations A, B, and C correspond to the red MS, while populations C and D are connected to the middle and the blue MS. In this paper we exploit Hubble-Space-Telescope photometry to investigate the radial distribution of the red, the middle and the blue MS from the cluster center out to about 8.5 arcmin. Our analysis shows that the radial distribution of each of the three MSs is different. In particular...

  17. The Hubble Space Telescope UV Legacy Survey of Galactic globular clusters - X. The radial distribution of stellar populations in NGC 2808

    Science.gov (United States)

    Simioni, M.; Milone, A. P.; Bedin, L. R.; Aparicio, A.; Piotto, G.; Vesperini, E.; Hong, J.

    2016-11-01

    Due to their extreme helium abundance, the multiple stellar populations of the globular cluster NGC 2808 have been widely investigated from a photometric, spectroscopic, and kinematic perspective. The most striking feature of the colour-magnitude diagram of NGC 2808 is the triple main sequence (MS), with the red MS corresponding to a stellar population with primordial helium, and the middle and the blue MS being enhanced in helium up to Y ˜ 0.32 and ˜0.38, respectively. A recent study has revealed that this massive cluster hosts at least five distinct stellar populations (A, B, C, D, and E). Among them populations A, B, and C correspond to the red MS, while populations C and D are connected to the middle and the blue MS. In this paper, we exploit Hubble Space Telescope photometry to investigate the radial distribution of the red, the middle, and the blue MS from the cluster centre out to about 8.5 arcmin. Our analysis shows that the radial distribution of each of the three MSs is different. In particular, as predicted from multiple-population formation models, both the blue MS and the middle MS appears to be more concentrated than the red MS with a significance level for this result which is above 3σ.

  18. THE FLAT TRANSMISSION SPECTRUM OF THE SUPER-EARTH GJ1214b FROM WIDE FIELD CAMERA 3 ON THE HUBBLE SPACE TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Berta, Zachory K.; Charbonneau, David; Desert, Jean-Michel; Irwin, Jonathan [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Miller-Ricci Kempton, Eliza; Fortney, Jonathan J.; Nutzman, Philip [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); McCullough, Peter R. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Burke, Christopher J. [SETI Institute/NASA Ames Research Center, M/S 244-30, Moffett Field, CA 94035 (United States); Homeier, Derek, E-mail: zberta@cfa.harvard.edu [Centre de Recherche Astrophysique de Lyon, UMR 5574, CNRS, Universite de Lyon, Ecole Normale Superieure de Lyon, F-69364 Lyon Cedex 07 (France)

    2012-03-01

    Capitalizing on the observational advantage offered by its tiny M dwarf host, we present Hubble Space Telescope/Wide Field Camera 3 (WFC3) grism measurements of the transmission spectrum of the super-Earth exoplanet GJ1214b. These are the first published WFC3 observations of a transiting exoplanet atmosphere. After correcting for a ramp-like instrumental systematic, we achieve nearly photon-limited precision in these observations, finding the transmission spectrum of GJ1214b to be flat between 1.1 and 1.7 {mu}m. Inconsistent with a cloud-free solar composition atmosphere at 8.2{sigma}, the measured achromatic transit depth most likely implies a large mean molecular weight for GJ1214b's outer envelope. A dense atmosphere rules out bulk compositions for GJ1214b that explain its large radius by the presence of a very low density gas layer surrounding the planet. High-altitude clouds can alternatively explain the flat transmission spectrum, but they would need to be optically thick up to 10 mbar or consist of particles with a range of sizes approaching 1 {mu}m in diameter.

  19. The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters -- XI. The horizontal branch in NGC\\,6388 and NGC\\,6441

    CERN Document Server

    Tailo, M; Milone, A P; Bellini, A; Ventura, P; Di Criscienzo, M; Cassisi, S; Piotto, G; Salaris, M; Brown, T M; Vesperini, E; Bedin, L R; Marino, A F; Nardiello, D; Anderson, J

    2016-01-01

    The Hubble Space Telescope UV Legacy survey of Galactic Globular Clusters (GC) is characterising many different aspects of their multiple stellar populations. The "Grundahl-jump" (G-jump) is a discontinuity in ultraviolet brightness of blue horizontal branch (HB) stars, signalling the onset of radiative metal levitation. The HB Legacy data confirmed that the G-jump is located at the same T$_{eff}$ ($\\simeq$11,500 K) in nearly all clusters. The only exceptions are the metal-rich clusters NGC 6388 and NGC 6441, where the G-jump occurs at T$_{eff}\\simeq$13-14,000K. We compute synthetic HB models based on new evolutionary tracks including the effect of helium diffusion, and approximately accounting for the effect of metal levitation in a stable atmosphere. Our models show that the G-jump location depends on the interplay between the timescale of diffusion and the timescale of the evolution in the T$_{eff}$ range 11,500 K$\\lessapprox$T$_{eff}\\lessapprox$14,000 K. The G-jump becomes hotter than 11,500 K only for st...

  20. The Hubble space telescope UV legacy survey of galactic globular clusters. I. Overview of the project and detection of multiple stellar populations

    Energy Technology Data Exchange (ETDEWEB)

    Piotto, G.; Nardiello, D.; Cunial, A., E-mail: giampaolo.piotto@unipd.it, E-mail: domenico.nardiello@studenti.unipd.it, E-mail: andrea.cunial@studenti.unipd.it [Dipartimento di Fisica e Astronomia “Galileo Galilei,” Università di Padova, Vicolo dell’Osservatorio 3, I-35122 Padova (Italy); and others

    2015-03-01

    In this paper we describe a new UV-initiative Hubble Space Telescope project (GO-13297) that will complement the existing F606W and F814W database of the Advanced Camera for Surveys Globular Cluster (GC) Treasury by imaging most of its clusters through UV/blue WFC3/UVIS filters F275W, F336W, and F438W. This “magic trio” of filters has shown an uncanny ability to disentangle and characterize multiple population (MP) patterns in GCs in a way that is exquisitely sensitive to C, N, and O abundance variations. Combination of these passbands with those in the optical also gives the best leverage for measuring helium enrichment. The dozen clusters that had previously been observed in these bands exhibit a bewildering variety of MP patterns, and the new survey will map the full variance of the phenomenon. The ubiquity of multiple stellar generations in GCs has made the formation of these cornerstone objects more intriguing than ever; GC formation and the origin of their MPs have now become one and the same problem. In this paper we will describe the database and our data reduction strategy, as well as the uses we intend to make of the final photometry, astrometry, and PMs. We will also present preliminary color–magnitude diagrams from the data so far collected. These diagrams also draw on data from GO-12605 and GO-12311, which served as a pilot project for the present GO-13297.

  1. The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. II. The seven stellar populations of NGC7089 (M2)

    CERN Document Server

    Milone, A P; Piotto, G; Bedin, L R; Anderson, J; Renzini, A; King, I R; Bellini, A; Brown, T M; Cassisi, S; D'Antona, F; Jerjen, H; Nardiello, D; Salaris, M; van der Marel, R P; Vesperini, E; Yong, D; Aparicio, A; Sarajedini, A; Zoccali, M

    2014-01-01

    We present high-precision multi-band photometry for the globular cluster (GC) M2. We combine the analysis of the photometric data obtained from the Hubble Space Telescope UV Legacy Survey of Galactic GCs GO-13297, with chemical abundances by Yong et al.(2014), and compare the photometry with models in order to analyze the multiple stellar sequences we identified in the color-magnitude diagram (CMD). We find three main stellar components, composed of metal-poor, metal-intermediate, and metal-rich stars (hereafter referred to as population A, B, and C, respectively). The components A and B include stars with different $s$-process element abundances. They host six sub-populations with different light-element abundances, and exhibit an internal variation in helium up to Delta Y~0.07 dex. In contrast with M22, another cluster characterized by the presence of populations with different metallicities, M2 contains a third stellar component, C, which shows neither evidence for sub-populations nor an internal spread in...

  2. The Hubble Space Telescope Wide Field Camera 3 Early Release Science data: Panchromatic Faint Object Counts from 0.2-2 microns wavelength

    CERN Document Server

    Windhorst, Rogier A; Hathi, Nimish P; McCarthy, Patrick J; Ryan, Russell E; Jr.,; Yan, Haojing; Baldry, Ivan K; Driver, Simon P; Frogel, Jay A; Hill, David T; Kelvin, Lee S; Koekemoer, Anton M; Mechtley, Matt; O'Connell, Robert W; Robotham, Aaron S G; Rutkowski, Michael J; Seibert, Mark; Tuffs, Richard J; Balick, Bruce; Bond, Howard E; Bushouse, Howard; Calzetti, Daniela; Crockett, Mark; Disney, Michael J; Dopita, Michael A; Hall, Donald N B; Holtzman, Jon A; Kaviraj, Sugata; Kimble, Randy A; MacKenty, John W; Mutchler, Max; Paresce, Francesco; Saha, Abihit; Silk, Joseph I; Trauger, John; Walker, Alistair R; Whitmore, Bradley C; Young, Erick

    2010-01-01

    We describe the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) Early Release Science (ERS) observations in the Great Observatories Origins Deep Survey (GOODS) South field. The new WFC3 ERS data provide calibrated, drizzled mosaics in the mid-UV filters F225W, F275W, and F336W, as well as in the near-IR filters F098W (\\Ys), F125W (J), and F160W (H) in 1-2 HST orbits per filter. Together with the existing HST Advanced Camera for Surveys (ACS) GOODS-South mosaics in the BVi'z' filters, these panchromatic 10-band ERS data cover 40-50 square arcmin from from 0.2-1.7 \\mum\\ in wavelength at 0\\arcspt 07-0\\arcspt 15 FWHM resolution and 0\\arcspt 090 multidrizzled pixels to depths of AB\\cle 26.0-27.0 mag (5-sigma) for point sources, and AB\\cle 25.5-26.5 mag for compact galaxies. In this paper, we describe: a) the scientific rationale, and the data taking plus reduction procedures of the panchromatic 10-band ERS mosaics; b) the procedure of generating object catalogs across the 10 different ERS filters, and the ...

  3. A Panchromatic Catalog of Early-Type Galaxies at Intermediate Redshift in the Hubble Space Telescope Wide Field Camera 3 Early Release Science Field

    CERN Document Server

    Rutkowski, M J; Kaviraj, S; O'Connell, R W; Hathi, N P; Windhorst, R A; Ryan, R E; Crockett, R M; Yan, H; Kimble, R A; Silk, J; McCarthy, P J; Koekemoer, A; Balick, B; Bond, H E; Calzetti, D; Disney, M J; Dopita, M A; Frogel, J A; Hall, D N B; Holtzman, J A; Paresce, F; Saha, A; Trauger, J T; Walker, A R; Whitmore, B C; Young, E T

    2012-01-01

    In the first of a series of forthcoming publications, we present a panchromatic catalog of 102 visually-selected early-type galaxies (ETGs) from observations in the Early Release Science (ERS) program with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) of the Great Observatories Origins Deep Survey-South (GOODS-S) field. Our ETGs span a large redshift range, 0.35 < z < 1.5, with each redshift spectroscopically-confirmed by previous published surveys of the ERS field. We combine our measured WFC3 ERS and ACS GOODS-S photometry to gain continuous sensitivity from the rest-frame far-UV to near-IR emission for each ETG. The superior spatial resolution of the HST over this panchromatic baseline allows us to classify the ETGs by their small-scale internal structures, as well as their local environment. By fitting stellar population spectral templates to the broad-band photometry of the ETGs, we determine that the average masses of the ETGs are comparable to the characteristic stellar mass ...

  4. Hubble Space Telescope proper motion (HSTPROMO) catalogs of Galactic globular clusters. IV. Kinematic profiles and average masses of blue straggler stars

    CERN Document Server

    Baldwin, A T; van der Marel, R P; Bianchini, P; Bellini, A; Anderson, J

    2016-01-01

    We make use of the Hubble Space Telescope proper-motion catalogs derived by Bellini et al. (2014) to produce the first radial velocity-dispersion profiles sigma(R) for blue straggler stars (BSSs) in Galactic globular clusters (GCs), as well as the first dynamical estimates for the average mass of the entire BSS population. We show that BSSs typically have lower velocity dispersions than stars with mass equal to the main-sequence turnoff mass, as one would expect for a more massive population of stars. Since GCs are expected to experience some degree of energy equipartition, we use the relation sigma~M^-eta, where eta is related to the degree of energy equipartition, along with our velocity-dispersion profiles to estimate BSS masses. We estimate eta as a function of cluster relaxation from recent Monte Carlo cluster simulations by Bianchini et al. (2016b) and then derive an average mass ratio M_BSS /M_MSTO=1.50+/-0.14 and an average mass M_BSS=1.22+/-0.12 M_Sun from 598 BSSs across 19 GCs. The final error bars...

  5. Astrometry with the Hubble Space Telescope: Trigonometric Parallaxes of Planetary Nebula Nuclei: NGC 6853, NGC 7293, Abell 31, and DeHt 5

    CERN Document Server

    Benedict, G Fritz; Napiwotzki, Ralf; Harrison, Thomas E; Harris, Hugh C; Nelan, Edmund; Bond, Howard E; Patterson, Richard J; Ciardullo, Robin

    2009-01-01

    We present absolute parallaxes and relative proper motions for the central stars of the planetary nebulae NGC 6853 (The Dumbbell), NGC 7293 (The Helix), Abell 31, and DeHt 5. This paper details our reduction and analysis using DeHt 5 as an example. We obtain these planetary nebula nuclei (PNNi) parallaxes with astrometric data from Fine Guidance Sensors FGS 1R and FGS 3, white-light interferometers on the Hubble Space Telescope (HST). Proper motions, spectral classifications and VJHKT_2M and DDO51 photometry of the stars comprising the astrometric reference frames provide spectrophotometric estimates of reference star absolute parallaxes. Introducing these into our model as observations with error, we determine absolute parallaxes for each PNN. Weighted averaging with previous independent parallax measurements yields an average parallax precision, \\sigma_{\\pi}/\\pi = 5 %. Derived distances are: d_{NGC 6853}=405^{+28}_{-25}pc, d_{NGC 7293}=216^{+14}_{-12} pc, d_{Abell 31} = 621^{+91}_{-70} pc, and d_{DeHt 5} = ...

  6. A Hubble Space Telescope Lensing Survey of X-ray Luminous Galaxy Clusters A Multiply-imaged Extremely Red Galaxy at z=1.6

    CERN Document Server

    Smith, G P; Kneib, J P; Davis, C J; Takamiya, M; Ebeling, H; Czoske, O; Smith, Graham P.; Smail, Ian

    2002-01-01

    We present near-infrared spectroscopy and Hubble Space Telescope (HST) imaging of EROJ003707+0909.5, the brightest of three gravitationally-lensed images of an Extremely Red Object (ERO) at z=1.6, in the field of the massive cluster A68 (z=0.255). We exploit the superlative resolution of our HST data and the enhanced spatial resolution and sensitivity afforded by the lens amplification to reconstruct the source-plane properties of this ERO. Our morphological and photometric analysis reveals that EROJ003707 is an L* early-type disk-galaxy and we estimate that ~10 per cent of EROs with (R-K)>=5.3 and K<=21 may have similar properties. The unique association of passive EROs with elliptical galaxies therefore appears to be too simplistic. We speculate on the evolution of EROJ003707: if gas continues to cool onto this galaxy in the manner predicted by hierarchical galaxy formation models, then by the present day, EROJ003707 could evolve into a very luminous spiral galaxy.

  7. Chandra X-ray and Hubble Space Telescope Imaging of Optically Selected Kiloparsec-Scale Binary Active Galactic Nuclei II: Host Galaxy Morphology and AGN Activity

    CERN Document Server

    Shangguan, Jinyi; Ho, Luis C; Shen, Yue; Peng, Chien Y; Greene, Jenny E; Strauss, Michael A

    2016-01-01

    Binary active galactic nuclei (AGNs) provide clues to how gas-rich mergers trigger and fuel AGNs and how supermassive black hole (SMBH) pairs evolve in a gas-rich environment. While significant effort has been invested in their identification, the detailed properties of binary AGNs and their host galaxies are still poorly constrained. In a companion paper, we examined the nature of ionizing sources in the double nuclei of four kpc-scale binary AGNs with redshifts between 0.1~0.2. Here, we present their host galaxy morphology based on F336W (U-band) and F105W (Y-band) images taken by the Wide Field Camera 3 (WFC3) onboard the Hubble Space Telescope. Our targets have double-peaked narrow emission lines and were confirmed to host binary AGNs with follow up observations. We find that kpc-scale binary AGNs occur in galaxy mergers with diverse morphological types. There are three major mergers with intermediate morphologies and a minor merger with a dominant disk component. We estimate the masses of the SMBHs from ...

  8. Hubble Space Telescope Pre-Perihelion ACS/WFC Imaging Polarimetry of Comet ISON (C/2012 S1) at 3.81 AU

    CERN Document Server

    Hines, Dean C; Zubko, Evgenij; Muinonen, Karri; Shkuratov, Yuriy; Kaydash, Vadim G; Knight, Matthew M; Sitko, Michael L; Lisse, Carey M; Mutchler, Max; Hammer, Derek; Yanamandra-Fisher, Padmavati A

    2013-01-01

    We present polarization images of Comet ISON (C/2012 S1) taken with the Hubble Space Telescope (HST) on UTC 2013 May 8 (rh = 3.81 AU, Delta = 4.34 AU), when the phase angle was alpha = 12.16 degrees. This phase angle is approximately centered in the negative polarization branch for cometary dust. The region beyond 1000 km from the nucleus shows a negative polarization amplitude of p% -1.6%. Within 1000 km of the nucleus, the polarization position angle rotates to be approximately perpendicular to the scattering plane, with an amplitude p% +2.5%. Such positive polarization has been observed previously as a characteristic feature of cometary jets, and we show that Comet ISON does indeed harbor a jet-like feature. These HST observations of Comet ISON represent the first visible light, imaging polarimetry with sub-arcsecond spatial resolution of a Nearly Isotropic Comet (NIC) beyond 3.8 AU from the Sun at a small phase angle. The observations provide an early glimpse of the properties of the cometary dust preserv...

  9. MC^2: Mapping the Dark Matter Distribution of the "Toothbrush" Cluster RX J0603.3+4214 with Hubble Space Telescope and Subaru Weak-lensing

    CERN Document Server

    Jee, M James; Stroe, Andra; Wittman, David; Van Weeren, Reinout J; Bruggen, Marcus; Bradac, Marusa; Rottgering, Huub

    2015-01-01

    The galaxy cluster RX J0603.3+4214 at z=0.225 is one of the rarest clusters boasting an extremely large (~2 Mpc) radio-relic. Because of the remarkable morphology of the relic, the cluster is nicknamed "Toothbrush Cluster". Although the cluster's underlying mass distribution is one of the critical pieces of information needed to reconstruct the merger scenario responsible for the puzzling radio-relic morphology, its proximity to the Galactic plane b~10 deg has imposed significant observational challenges. We present a high-resolution weak-lensing study of the cluster with Subaru/Suprime Cam and Hubble Space Telescope imaging data. Our mass reconstruction reveals that the cluster is comprised of complicated dark matter substructures closely tracing the galaxy distribution, however in contrast with the relatively simple binary X-ray morphology. Nevertheless, we find that the cluster mass is still dominated by the two most massive clumps aligned north-south with a ~3:1 mass ratio (M_{200}=6.29_{-1.62}^{+2.24} x ...

  10. CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products and Mosaics

    CERN Document Server

    Koekemoer, Anton M; Ferguson, Henry C; Grogin, Norman A; Kocevski, Dale D; Koo, David C; Lai, Kamson; Lotz, Jennifer M; Lucas, Ray A; McGrath, Elizabeth J; Ogaz, Sara; Rajan, Abhijith; Riess, Adam G; Rodney, Steve A; Strolger, Louis; Casertano, Stefano; Dahlen, Tomas; Dickinson, Mark; Dolch, Timothy; Fontana, Adriano; Giavalisco, Mauro; Grazian, Andrea; Guo, Yicheng; Hathi, Nimish P; Huang, Kuang-Han; van der Wel, Arjen; Yan, Hao-Jing; Acquaviva, Viviana; Almaini, David M Alexander Omar; Ashby, Matthew L N; Barden, Marco; Bell, Eric F; Bournaud, Frédéric; Brown, Thomas M; Caputi, Karina I; Cassata, Paolo; Challis, Peter; Chary, Ranga-Ram; Cheung, Edmond; Cirasuolo, Michele; Conselice, Christopher J; Cooray, Asantha Roshan; Croton, Darren J; Daddi, Emanuele; Davé, Romeel; de Mello, Duilia F; de Ravel, Loic; Dekel, Avishai; Donley, Jennifer L; Dunlop, James S; Dutton, Aaron A; Elbaz, David; Fazio, Giovanni G; Filippenko, Alex V; Finkelstein, Steven L; Frazer, Chris; Gardner, Jonathan P; Garnavich, Peter M; Gawiser, Eric; Gruetzbauch, Ruth; Hartley, Will G; Häussler, Boris; Herrington, Jessica; Hopkins, Philip F; Huang, Jia-Sheng; Jha, Saurabh; Johnson, Andrew; Kartaltepe, Jeyhan S; Khostovan, Ali Ahmad; Kirshner, Robert P; Lani, Caterina; Lee, Kyoung-Soo; Li, Weidong; Madau, Piero; McCarthy, Patrick J; McIntosh, Daniel H; McLure, Ross J; McPartland, Conor; Mobasher, Bahram; Moreira, Heidi; Mortlock, Alice; Moustakas, Leonidas A; Mozena, Mark; Nandra, Kirpal; Newman, Jeffrey A; Nielsen, Jennifer L; Niemi, Sami; Noeske, Kai G; Papovich, Casey J; Pentericci, Laura; Pope, Alexandra; Primack, Joel R; Ravindranath, Swara; Reddy, Naveen A; Renzini, Alvio; Rix, Hans-Walter; Robaina, Aday R; Rosario, David J; Rosati, Piero; Salimbeni, Sara; Scarlata, Claudia; Siana, Brian; Simard, Luc; Smidt, Joseph; Snyder, Diana; Somerville, Rachel S; Spinrad, Hyron; Straughn, Amber N; Telford, Olivia; Teplitz, Harry I; Trump, Jonathan R; Vargas, Carlos; Villforth, Carolin; Wagner, Cory R; Wandro, Pat; Wechsler, Risa H; Weiner, Benjamin J; Wiklind, Tommy; Wild, Vivienne; Wilson, Grant; Wuyts, Stijn; Yun, Min S

    2011-01-01

    This paper describes the Hubble Space Telescope imaging data products and data reduction procedures for the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS). This survey is designed to document the evolution of galaxies and black holes at $z\\sim1.5-8$, and to study Type Ia SNe beyond $z>1.5$. Five premier multi-wavelength sky regions are selected, each with extensive multiwavelength observations. The primary CANDELS data consist of imaging obtained in the Wide Field Camera 3 / infrared channel (WFC3/IR) and UVIS channel, along with the Advanced Camera for Surveys (ACS). The CANDELS/Deep survey covers \\sim125 square arcminutes within GOODS-N and GOODS-S, while the remainder consists of the CANDELS/Wide survey, achieving a total of \\sim800 square arcminutes across GOODS and three additional fields (EGS, COSMOS, and UDS). We summarize the observational aspects of the survey as motivated by the scientific goals and present a detailed description of the data reduction procedures and products from...

  11. The Initial Mass Function of the Stellar Association NGC 602 in the Small Magellanic Cloud with Hubble Space Telescope ACS Observations

    CERN Document Server

    Schmalzl, Markus; Dolphin, Andrew E; Henning, Thomas

    2008-01-01

    We present our photometric study of the stellar association NGC 602 in the wing of the Small Magellanic Cloud (SMC). The data were taken in the filters F555W and F814W using the Advanced Camera for Surveys (ACS) on-board the Hubble Space Telescope (HST). Photometry was performed using the ACS module of the stellar photometry package DOLPHOT. We detected more than 5,500 stars with a magnitude range of 14 \\lsim m_{555} \\lsim 28 mag. Three prominent stellar concentrations are identified with star counts in the observed field, the association NGC 602 itself, and two clusters, one of them not being currently in any known catalog. The Color-Magnitude Diagrams (CMDs) of both clusters show features typical for young open clusters, while that of the association reveals bright main sequence (MS) and faint pre-main sequence (PMS) stars as the members of the system. We construct the initial mass spectrum (IMS) of the association by applying an age-independent method of counting the PMS stars within evolutionary tracks, w...

  12. New Hubble Space Telescope Discoveries of Type Ia Supernovae at z > 1: Narrowing Constraints on the Early Behavior of Dark Energy

    CERN Document Server

    Riess, A G; Casertano, S; Ferguson, H C; Mobasher, B; Gold, B; Challis, P J; Filippenko, A V; Jha, S; Li, W; Tonry, J; Foley, R; Kirshner, R P; Dickinson, M; MacDonald, E; Eisenstein, D; Livio, M; Younger, J; Xu, C; Dahlen, T; Stern, D; Riess, Adam G.; Strolger, Louis-Gregory; Casertano, Stefano; Ferguson, Henry C.; Mobasher, Bahram; Gold, Ben; Challis, Peter J.; Filippenko, Alexei V.; Jha, Saurabh; Li, Weidong; Tonry, John; Foley, Ryan; Kirshner, Robert P.; Dickinson, Mark; Donald, Emily Mac; Eisenstein, Daniel; Livio, Mario; Younger, Josh; Xu, Chun; Dahlen, Tomas; Stern, Daniel

    2006-01-01

    We have discovered 21 new Type Ia supernovae (SNe Ia) with the Hubble Space Telescope (HST) and have used them to trace the history of cosmic expansion over the last 10 billion years. These objects, which include 13 spectroscopically confirmed SNe Ia at z > 1, were discovered during 14 epochs of reimaging of the GOODS fields North and South over two years with the Advanced Camera for Surveys on HST. Together with a recalibration of our previous HST-discovered SNe Ia, the full sample of 23 SNe Ia at z > 1 provides the highest-redshift sample known. Combined with previous SN Ia datasets, we measured H(z) at discrete, uncorrelated epochs, reducing the uncertainty of H(z>1) from 50% to under 20%, strengthening the evidence for a cosmic jerk--the transition from deceleration in the past to acceleration in the present. The unique leverage of the HST high-redshift SNe Ia provides the first meaningful constraint on the dark energy equation-of-state parameter at z >1. The result remains consistent with a cosmological ...

  13. A High-Resolution Multiband Survey of Westerlund 2 With the Hubble Space Telescope. II. Mass accretion in the Pre-Main Sequence Population

    CERN Document Server

    Zeidler, Peter; Nota, Antonella; Sabbi, Elena; Pasquali, Anna; Tosi, Monica; Bonanos, Alceste Z; Christian, Carol

    2016-01-01

    We present a detailed analysis of the pre-main-sequence (PMS) population of the young star cluster Westerlund~2 (Wd2), the central ionizing cluster of the HII region RCW 49, using data from a high resolution multi-band survey with the Hubble Space Telescope. The data were acquired with the Advanced Camera for Surveys in the F555W, F814W, and F658N filters and with the Wide Field Camera 3 in the F125W, F160W, and F128N filters. We find a mean age of the region of 1.04+-0.72 Myr. The combination of dereddened F555W and F814W photometry in combination with F658N photometry allows us to study and identify stars with H_alpha excess emission. With a careful selection of 240 bona-fide PMS H_alpha excess emitters we were able to determine their H_alpha luminosity, which has a mean value L(H_alpha)=1.67 x 10^{-31} erg s^{-1}. Using the PARSEC 1.2S isochrones to obtain the stellar parameters of the PMS stars we determined a mean mass accretion rate \\dot M_acc=4.43 x 10^{-8} M_sun yr^{-1} per star. A careful analysis of...

  14. The Expanding Nebular Remnant of the Recurrent Nova RS Ophiuchi (2006): II. Modeling of Combined Hubble Space Telescope Imaging and Ground-based Spectroscopy

    CERN Document Server

    Ribeiro, V A R M; Darnley, M J; Harman, D J; Newsam, A M; O'Brien, T J; Bohigas, J; Echevarría, J M; Bond, H E; Chavushyan, V H; Costero, R; Coziol, R; Evans, A; Eyres, S P S; León-Tavares, J; Richer, M G; Tovmassian, G; Starrfield, S; Zharikov, S V

    2009-01-01

    We report Hubble Space Telescope imaging, obtained 155 and 449 days after the 2006 outburst of the recurrent nova RS Ophiuchi, together with ground-based spectroscopic observations, obtained from the Observatorio Astron\\'omico Nacional en San Pedro M\\'artir, Baja California, M\\'exico and at the Observatorio Astrof\\'isico Guillermo Haro, at Cananea, Sonora, M\\'exico. The observations at the first epoch were used as inputs to model the geometry and kinematic structure of the evolving RS Oph nebular remnant. We find that the modeled remnant comprises two distinct co-aligned bipolar components; a low-velocity, high-density innermost (hour glass) region and a more extended, high-velocity (dumbbell) structure. This overall structure is in agreement with that deduced from radio observations and optical interferometry at earlier epochs. We find that the asymmetry observed in the west lobe is an instrumental effect caused by the profile of the HST filter and hence demonstrate that this lobe is approaching the observer...

  15. The Hubble Space Telescope Cluster Supernova Survey: III. Correlated Properties of Type Ia Supernovae and Their Hosts at 0.9 < z < 1.46

    CERN Document Server

    Meyers, J; Barbary, K; Barrientos, L F; Brodwin, M; Dawson, K S; Deustua, S; Doi, M; Eisenhardt, P; Faccioli, L; Fakhouri, H K; Fruchter, A S; Gilbank, D G; Gladders, M D; Goldhaber, G; Gonzalez, A H; Hattori, T; Hsiao, E; Ihara, Y; Kashikawa, N; Koester, B; Konishi, K; Lidman, C; Lubin, L; Morokuma, T; Oda, T; Perlmutter, S; Postman, M; Ripoche, P; Rosati, P; Rubin, D; Rykoff, E; Spadafora, A; Stanford, S A; Suzuki, N; Takanashi, N; Tokita, K; Yasuda, N

    2012-01-01

    Using the sample of Type Ia supernovae (SNe Ia) discovered by the Hubble Space Telescope (HST) Cluster Supernova Survey and augmented with HST-observed SNe Ia in the GOODS fields, we search for correlations between the properties of SNe and their host galaxies at high redshift. We use galaxy color and quantitative morphology to determine the red sequence in 25 clusters and develop a model to distinguish passively evolving early-type galaxies from star-forming galaxies in both clusters and the field. With this approach, we identify six SN Ia hosts that are early-type cluster members and eleven SN Ia hosts that are early-type field galaxies. We confirm for the first time at z>0.9 that SNe Ia hosted by early-type galaxies brighten and fade more quickly than SNe Ia hosted by late-type galaxies. We also show that the two samples of hosts produce SNe Ia with similar color distributions. The relatively simple spectral energy distributions (SEDs) expected for passive galaxies enable us to measure stellar masses of ea...

  16. Ultra-Deep Hubble Space Telescope Imaging of the Small Magellanic Cloud: The Initial Mass Function of Stars with M <~ 1 Msun

    CERN Document Server

    Kalirai, Jason S; Dotter, Aaron; Richer, Harvey B; Fahlman, Gregory G; Hansen, Brad M S; Hurley, Jarrod; Reid, I Neill; Rich, R Michael; Shara, Michael M

    2012-01-01

    We present a new measurement of the stellar initial mass function (IMF) based on ultra-deep, high-resolution photometry of >5,000 stars in the outskirts of the Small Magellanic Cloud (SMC) galaxy. The Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) observations reveal this rich, co-spatial population behind the foreground globular cluster 47 Tuc, which we targeted for 121 HST orbits. The stellar main sequence of the SMC is measured in the F606W, F814W color-magnitude diagram (CMD) down to ~30th magnitude, and is cleanly separated from the foreground star cluster population using proper motions. We simulate the SMC population by extracting stellar masses (single and unresolved binaries) from specific IMFs, and converting those masses to luminosities in our bandpasses. The corresponding photometry for these simulated stars is drawn directly from a rich cloud of 4 million artificial stars, thereby accounting for the real photometric scatter and completeness of the data. Over a continuous and well ...

  17. The Collapse of the Wien Tail in the Coldest Brown Dwarf? Hubble Space Telescope Near-Infrared Photometry of WISE J085510.83-071442.5

    CERN Document Server

    Schneider, Adam C; Kirkpatrick, J Davy; Gelino, Chris R

    2016-01-01

    We present Hubble Space Telescope (HST) near-infrared photometry of the coldest known brown dwarf, WISE J085510.83$-$071442.5 (WISE 0855$-$0714). WISE 0855$-$0714 was observed with the Wide Field Camera 3 (WFC3) aboard HST using the F105W, F125W, and F160W filters, which approximate the $Y$, $J$, and $H$ near-infrared bands. WISE 0855$-$0714 is undetected at F105W with a corresponding 2$\\sigma$ magnitude limit of $\\sim$26.9. We marginally detect WISE 0855$-$0714 in the F125W images (S/N $\\sim$4), with a measured magnitude of 26.41 $\\pm$ 0.27, more than a magnitude fainter than the $J-$band magnitude reported by Faherty and coworkers. WISE J0855$-$0714 is clearly detected in the F160W band, with a magnitude of 23.90 $\\pm$ 0.02, the first secure detection of WISE 0855$-$0714 in the near-infrared. Based on these data, we find that WISE 0855$-$0714 has extremely red F105W$-$F125W and F125W$-$F160W colors relative to other known Y dwarfs. We find that when compared to the models of Saumon et al. and Morley et al.,...

  18. The Hubble Space Telescope UV Legacy Survey of Galactic globular clusters - XI. The horizontal branch in NGC 6388 and NGC 6441

    Science.gov (United States)

    Tailo, M.; D'Antona, F.; Milone, A. P.; Bellini, A.; Ventura, P.; Di Criscienzo, M.; Cassisi, S.; Piotto, G.; Salaris, M.; Brown, T. M.; Vesperini, E.; Bedin, L. R.; Marino, A. F.; Nardiello, D.; Anderson, J.

    2017-02-01

    The Hubble Space Telescope UV Legacy survey of Galactic globular clusters (GC) is characterizing many different aspects of their multiple stellar populations. The `Grundahl-jump' (G-jump) is a discontinuity in ultraviolet brightness of blue horizontal branch (HB) stars, signalling the onset of radiative metal levitation. The HB Legacy data confirmed that the G-jump is located at the same Teff (≃11 500 K) in nearly all clusters. The only exceptions are the metal-rich clusters NGC 6388 and NGC 6441, where the G-jump occurs at Teff ≃ 13-14 000 K. We compute synthetic HB models based on new evolutionary tracks including the effect of helium diffusion, and approximately accounting for the effect of metal levitation in a stable atmosphere. Our models show that the G-jump location depends on the interplay between the time-scale of diffusion and the time-scale of the evolution in the Teff range 11 500 K≲Teff≲14 000 K. The G-jump becomes hotter than 11 500 K only for stars that have, in this Teff range, a helium mass fraction Y ≳ 0.35. Similarly high Y values are also consistent with the modelling of the HB in NGC 6388 and NGC 6441. In these clusters, we predict that a significant fraction of HB stars show helium in their spectra above 11 500 K, and full helium settling should only be found beyond the hotter G-jump.

  19. NEAR-INFRARED IMAGING OF A z = 6.42 QUASAR HOST GALAXY WITH THE HUBBLE SPACE TELESCOPE WIDE FIELD CAMERA 3

    Energy Technology Data Exchange (ETDEWEB)

    Mechtley, M.; Windhorst, R. A.; Cohen, S. H.; Jansen, R. A.; Scannapieco, E. [School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, AZ 85287 (United States); Ryan, R. E.; Koekemoer, A. M. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Schneider, G.; Fan, X. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Hathi, N. P. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Keel, W. C. [Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487 (United States); Roettgering, H. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA, Leiden (Netherlands); Schneider, D. P. [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Strauss, M. A. [Princeton University Observatory, Princeton, NJ 08544 (United States); Yan, H. J. [Department of Physics and Astronomy, The University of Missouri, 701 South College Ave, Columbia, MO 65211 (United States)

    2012-09-10

    We report on deep near-infrared F125W (J) and F160W (H) Hubble Space Telescope Wide Field Camera 3 images of the z = 6.42 quasar J1148+5251 to attempt to detect rest-frame near-ultraviolet emission from the host galaxy. These observations included contemporaneous observations of a nearby star of similar near-infrared colors to measure temporal variations in the telescope and instrument point-spread function (PSF). We subtract the quasar point source using both this direct PSF and a model PSF. Using direct subtraction, we measure an upper limit for the quasar host galaxy of m{sub J} > 22.8 and m{sub H} > 23.0 AB mag (2 {sigma}). After subtracting our best model PSF, we measure a limiting surface brightness from 0.''3 to 0.''5 radius of {mu}{sub J} > 23.5 and {mu}{sub H} > 23.7 AB mag arcsec{sup -2} (2 {sigma}). We test the ability of the model subtraction method to recover the host galaxy flux by simulating host galaxies with varying integrated magnitude, effective radius, and Sersic index, and conducting the same analysis. These models indicate that the surface brightness limit ({mu}{sub J} > 23.5 AB mag arcsec{sup -2}) corresponds to an integrated upper limit of m{sub J} > 22-23 AB mag, consistent with the direct subtraction method. Combined with existing far-infrared observations, this gives an infrared excess log (IRX) > 1.0 and corresponding ultraviolet spectral slope {beta} > -1.2 {+-} 0.2. These values match those of most local luminous infrared galaxies, but are redder than those of almost all local star-forming galaxies and z {approx_equal} 6 Lyman break galaxies.

  20. The Mass Function of Main-Sequence Stars in NGC 6397 from Near-Infrared and Optical High-Resolution Hubble Space Telescope Observations

    Science.gov (United States)

    De Marchi, Guido; Paresce, Francesco; Pulone, Luigi

    2000-02-01

    We have investigated the properties of the stellar mass function in the globular cluster NGC 6397 through the use of a large set of Hubble Space Telescope (HST) observations. The latter include existing WFPC 2 images in the V and I bands, obtained at ~4.5‧ and 10' radial distances, as well as a series of deep images in the J and H bands obtained with the NIC 2 and NIC 3 cameras of the NICMOS instrument pointed, respectively, to regions located ~4.5‧ and ~3.2‧ from the center. These observations span the region from ~1 to ~3 times the cluster's half-light radius (rhl~=3') and have been subjected to the same, homogeneous data processing so as to guarantee that the ensuing results could be directly compared to one another. We have built color-magnitude diagrams that we use to measure the luminosity function of main-sequence stars extending from just below the turnoff all the way down to the hydrogen-burning limit. All luminosity functions derived in this way show the same, consistent behavior in that they all increase with decreasing luminosity up to a peak at MI~=8.5 or MH~=7 and then drop precipitously well before photometric incompleteness becomes significant. Within the observational uncertainties, at MI~=12 or MH~=10.5 (~0.09 Msolar) the luminosity functions are compatible with zero. The direct comparison of our NIC 2 field with previous WFPC 2 observations of the same area shows that down to MH~=11 there are no more faint, red stars than those already detected by the WFPC 2, thus excluding a significant population of faint, low-mass stars at the bottom of the main sequence. By applying the best available mass-luminosity relation appropriate to the metallicity of NGC 6397 and consistent with our color-magnitude diagrams to both the optical and the IR data, we obtain a mass function that shows a break in slope at ~0.3 Msolar. No single-exponent power-law distribution is compatible with these data, regardless of the value of the exponent. We find that a

  1. THE HUBBLE SPACE TELESCOPE CLUSTER SUPERNOVA SURVEY. III. CORRELATED PROPERTIES OF TYPE Ia SUPERNOVAE AND THEIR HOSTS AT 0.9 < z < 1.46

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, J.; Barbary, K.; Fakhouri, H. K.; Goldhaber, G. [Department of Physics, University of California Berkeley, Berkeley, CA 94720 (United States); Aldering, G.; Faccioli, L.; Hsiao, E. [E.O. Lawrence Berkeley National Lab, 1 Cyclotron Rd., Berkeley, CA 94720 (United States); Barrientos, L. F. [Departmento de Astronomia, Pontificia Universidad Catolica de Chile, Santiago (Chile); Brodwin, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Dawson, K. S. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Deustua, S.; Fruchter, A. S. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Doi, M.; Ihara, Y. [Institute of Astronomy, Graduate School of Science, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Eisenhardt, P. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Gilbank, D. G. [Department of Physics and Astronomy, University Of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Gladders, M. D. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Gonzalez, A. H. [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Hattori, T. [Subaru Telescope, National Astronomical Observatory of Japan, 650 North Aohaku Place, Hilo, HI 96720 (United States); Kashikawa, N., E-mail: jmeyers314@berkeley.edu [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Collaboration: Supernova Cosmology Project; and others

    2012-05-01

    Using the sample of Type Ia supernovae (SNe Ia) discovered by the Hubble Space Telescope (HST) Cluster Supernova Survey and augmented with HST-observed SNe Ia in the Great Observatories Origins Deep Survey (GOODS) fields, we search for correlations between the properties of SNe and their host galaxies at high redshift. We use galaxy color and quantitative morphology to determine the red sequence in 25 clusters and develop a model to distinguish passively evolving early-type galaxies from star-forming galaxies in both clusters and the field. With this approach, we identify 6 SN Ia hosts that are early-type cluster members and 11 SN Ia hosts that are early-type field galaxies. We confirm for the first time at z > 0.9 that SNe Ia hosted by early-type galaxies brighten and fade more quickly than SNe Ia hosted by late-type galaxies. We also show that the two samples of hosts produce SNe Ia with similar color distributions. The relatively simple spectral energy distributions expected for passive galaxies enable us to measure stellar masses of early-type SN hosts. In combination with stellar mass estimates of late-type GOODS SN hosts from Thomson and Chary, we investigate the correlation of host mass with Hubble residual observed at lower redshifts. Although the sample is small and the uncertainties are large, a hint of this relation is found at z > 0.9. By simultaneously fitting the average cluster galaxy formation history and dust content to the red-sequence scatters, we show that the reddening of early-type cluster SN hosts is likely E(B - V) {approx}< 0.06. The similarity of the field and cluster early-type host samples suggests that field early-type galaxies that lie on the red sequence may also be minimally affected by dust. Hence, the early-type-hosted SNe Ia studied here occupy a more favorable environment to use as well-characterized high-redshift standard candles than other SNe Ia.

  2. GK Per (Nova Persei 1901): HUBBLE SPACE TELESCOPE IMAGERY AND SPECTROSCOPY OF THE EJECTA, AND FIRST SPECTRUM OF THE JET-LIKE FEATURE

    Energy Technology Data Exchange (ETDEWEB)

    Shara, Michael M.; Zurek, David; Mizusawa, Trisha [Department of Astrophysics, American Museum of Natural History, Central Park West and 79th street, New York, NY 10024-5192 (United States); De Marco, Orsola [Department of Physics, Macquarie University, Sydney (Australia); Williams, Robert; Livio, Mario [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2012-06-15

    We have imaged the ejecta of GK Persei (Nova Persei 1901 A.D.) with the Hubble Space Telescope (HST), whose 0.1 arcsec resolution reveals hundreds of cometary-like structures with long axes aligned toward GK Per. One or both ends of the structures often show a brightness enhancement relative to the structures' middle sections, but there is no simple regularity to their morphologies (in contrast with, for example, the Helix nebula). Some of structures' morphologies suggest the presence of slow-moving or stationary material with which the ejecta is colliding, while others suggest shaping from a wind emanating from GK Per itself. The most detailed expansion map of any classical nova's ejecta was created by comparing HST images taken in successive years. Wide Field and Planetary Camera 2 narrowband images and Space Telescope Imaging Spectrograph spectra demonstrate that the physical conditions in this nova's ejecta vary strongly on spatial scales much smaller than those of the ejecta. Directly measuring accurate densities and compositions, and hence masses of this and other nova shells, will demand data at least as resolved spatially as those presented here. The filling factor of the ejecta is 1% or less, and the nova ejecta mass must be less than 10{sup -4} M{sub Sun }. A modest fraction of the emission nebulosities vary in brightness by up to a factor of two on timescales of one year. Finally, we present the deepest images yet obtained of a jet-like feature outside the main body of GK Per nebulosity, and the first spectrum of that feature. Dominated by strong, narrow emission lines of [N II], [O II], [O III], and [S II], this feature is probably a shock due to ejected material running into stationary interstellar matter, slowly moving ejecta from a previous nova episode, or circumbinary matter present before 1901. An upper limit to the mass of the jet is of order a few times 10{sup -6} M{sub Sun }. If the jet mass is close to this limit then the

  3. THE HUBBLE SPACE TELESCOPE UV LEGACY SURVEY OF GALACTIC GLOBULAR CLUSTERS: THE INTERNAL KINEMATICS OF THE MULTIPLE STELLAR POPULATIONS IN NGC 2808

    Energy Technology Data Exchange (ETDEWEB)

    Bellini, A.; Anderson, J.; Marel, R. P. van der [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Vesperini, E.; Hong, J. [Department of Astronomy, Indiana University, Bloomington, IN 47405 (United States); Piotto, G. [Dipartimento di Fisica e Astronomia “Galileo Galilei,” Università di Padova, v.co dell’Osservatorio 3, I-35122, Padova (Italy); Milone, A. P.; Marino, A. F. [Research School of Astronomy and Astrophysics, Australian National University, Mt Stromlo Observatory, via Cotter Rd, Weston, ACT 2611 (Australia); Bedin, L. R.; Renzini, A. [Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Padova, v.co dell’Osservatorio 5, I-35122, Padova (Italy); Cassisi, S. [Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Teramo, Via Mentore Maggini s.n.c., I-64100, Teramo (Italy); D’Antona, F. [Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Roma, Via Frascati 33, I-00040, Monteporzio Catone, Roma (Italy)

    2015-09-01

    Numerous observational studies have revealed the ubiquitous presence of multiple stellar populations in globular clusters and cast many difficult challenges for the study of the formation and dynamical history of these stellar systems. In this Letter we present the results of a study of the kinematic properties of multiple populations in NGC 2808 based on high-precision Hubble Space Telescope proper-motion measurements. In a recent study, Milone et al. identified five distinct populations (A–E) in NGC 2808. Populations D and E coincide with the helium-enhanced populations in the middle and the blue main sequences (mMS and bMS) previously discovered by Piotto et al.; populations A–C correspond to the redder main sequence that, in Piotto et al., was associated with the primordial stellar population. Our analysis shows that, in the outermost regions probed (between about 1.5 and 2 times the cluster half-light radius), the velocity distribution of populations D and E is radially anisotropic (the deviation from an isotropic distribution is significant at the ∼3.5σ level). Stars of populations D and E have a smaller tangential velocity dispersion than those of populations A–C, while no significant differences are found in the radial velocity dispersion. We present the results of a numerical simulation showing that the observed differences between the kinematics of these stellar populations are consistent with the expected kinematic fingerprint of the diffusion toward the cluster outer regions of stellar populations initially more centrally concentrated.

  4. ULTRA-DEEP HUBBLE SPACE TELESCOPE IMAGING OF THE SMALL MAGELLANIC CLOUD: THE INITIAL MASS FUNCTION OF STARS WITH M {approx}< 1 M {sub Sun}

    Energy Technology Data Exchange (ETDEWEB)

    Kalirai, Jason S.; Anderson, Jay; Dotter, Aaron; Reid, I. Neill [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Richer, Harvey B. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC (Canada); Fahlman, Gregory G. [National Research Council, Herzberg Institute of Astrophysics, Victoria, BC (Canada); Hansen, Brad M. S.; Rich, R. Michael [Division of Astronomy and Astrophysics, University of California at Los Angeles, Los Angeles, CA 90095 (United States); Hurley, Jarrod [Center for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn VIC 3122 (Australia); Shara, Michael M., E-mail: jkalirai@stsci.edu, E-mail: jayander@stsci.edu, E-mail: dotter@stsci.edu, E-mail: richer@astro.ubc.ca, E-mail: greg.fahlman@nrc-cnrc.gc.ca, E-mail: hansen@astro.ucla.edu, E-mail: rmr@astro.ucla.edu, E-mail: jhurley@swin.edu.au, E-mail: mshara@amnh.org [Department of Astrophysics, American Museum of Natural History, Central Park West and 79th Street, New York, NY 10024 (United States)

    2013-02-15

    We present a new measurement of the stellar initial mass function (IMF) based on ultra-deep, high-resolution photometry of >5000 stars in the outskirts of the Small Magellanic Cloud (SMC) galaxy. The Hubble Space Telescope (HST) Advanced Camera for Surveys observations reveal this rich, cospatial population behind the foreground globular cluster 47 Tuc, which we targeted for 121 HST orbits. The stellar main sequence of the SMC is measured in the F606W, F814W color-magnitude diagram down to {approx}30th magnitude, and is cleanly separated from the foreground star cluster population using proper motions. We simulate the SMC population by extracting stellar masses (single and unresolved binaries) from specific IMFs and converting those masses to luminosities in our bandpasses. The corresponding photometry for these simulated stars is drawn directly from a rich cloud of 4 million artificial stars, thereby accounting for the real photometric scatter and completeness of the data. Over a continuous and well-populated mass range of M = 0.37-0.93 M {sub Sun} (e.g., down to a {approx}75% completeness limit at F606W = 28.7), we demonstrate that the IMF is well represented by a single power-law form with slope {alpha} = -1.90 ({sup +0.15} {sub -0.10}) (3{sigma} error) (e.g., dN/dM{proportional_to} M {sup {alpha}}). This is shallower than the Salpeter slope of {alpha} = -2.35, which agrees with the observed stellar luminosity function at higher masses. Our results indicate that the IMF does not turn over to a more shallow power-law form within this mass range. We discuss implications of this result for the theory of star formation, the inferred masses of galaxies, and the (lack of a) variation of the IMF with metallicity.

  5. A High-resolution Multiband Survey of Westerlund 2 with the Hubble Space Telescope. III. The Present-day Stellar Mass Function

    Science.gov (United States)

    Zeidler, Peter; Nota, Antonella; Grebel, Eva K.; Sabbi, Elena; Pasquali, Anna; Tosi, Monica; Christian, Carol

    2017-03-01

    We present a detailed analysis of the spatial distribution of the stellar population and the present-day mass function (PDMF) of the Westerlund 2 (Wd2) region using the data from our high-resolution multiband survey with the Hubble Space Telescope. We used state-of-the-art artificial star tests to determine spatially resolved completeness maps for each of the broadband filters. We reach a level of completeness of 50% down to F555W=24.8 mag (0.7 {M}ȯ ) and F814W=23.3 mag (0.2 {M}ȯ ) in the optical and F125W=20.2 mag and F160W=19.4 mag (both 0.12 {M}ȯ ) in the infrared throughout the field of view. We had previously reported that the core of Wd2 consists of two clumps: namely the main cluster and the northern clump. From the spatial distribution of the completeness-corrected population, we find that their stellar surface densities are 1114 {stars} {{pc}}-2 and 555 {stars} {{pc}}-2, respectively, down to F814W=21.8 mag. We find that the PDMF of Wd2 has a slope of {{Γ }}=-1.46+/- 0.06, which translates to a total stellar cluster mass of (3.6+/- 0.3)\\cdot {10}4 {M}ȯ . The spatial analysis of the PDMF reveals that the cluster population is mass-segregated and most likely primordial. In addition, we report the detection of a stellar population of spatially uniformly distributed low-mass (< 0.15 {M}ȯ ) stars, extending into the gas ridges of the surrounding gas and dust cloud, as well as a confined region of reddened stars, likely caused by a foreground CO cloud. We find hints that a cloud–cloud collision might be the origin of the formation of Wd2.

  6. The Hubble Space Telescope Medium Deep Survey with the Wide Field and Planetary Camera. 1: Methodology and results on the field near 3C 273

    Science.gov (United States)

    Griffiths, R. E.; Ratnatunga, K. U.; Neuschaefer, L. W.; Casertano, S.; Im, M.; Wyckoff, E. W.; Ellis, R. S.; Gilmore, G. F.; Elson, R. A. W.; Glazebrook, K.

    1994-01-01

    We present results from the Medium Deep Survey (MDS), a Key Project using the Hubble Space Telescope (HST). Wide Field Camera (WFC) images of random fields have been taken in 'parallel mode' with an effective resolution of 0.2 sec full width at half maximum (FWHM) in the V(F555W) and I(F785LP) filters. The exposures presented here were targeted on a field away from 3C 273, and resulted in approximately 5 hr integration time in each filter. Detailed morphological structure is seen in galaxy images with total integrated magnitudes down to V approximately = 22.5 and I approximately = 21.5. Parameters are estimated that best fit the observed galaxy images, and 143 objects are identified (including 23 stars) in the field to a fainter limiting magnitude of I approximately = 23.5. We outline the extragalactic goals of the HST Medium Deep Survey, summarize our basic data reduction procedures, and present number (magnitude) counts, a color-magnitude diagram for the field, surface brightness profiles for the brighter galaxies, and best-fit half-light radii for the fainter galaxies as a function of apparent magnitude. A median galaxy half-light radius of 0.4 sec is measured, and the distribution of galaxy sizes versus magnitude is presented. We observe an apparent deficit of galaxies with half-light radii between approximately 0.6 sec and 1.5 sec, with respect to standard no-evolution or mild evolution cosmological models. An apparent excess of compact objects (half-light radii approximately 0.1 sec) is also observed with respect to those models. Finally, we find a small excess in the number of faint galaxy pairs and groups with respect to a random low-redshift field sample.

  7. INFRARED TRANSMISSION SPECTROSCOPY OF THE EXOPLANETS HD 209458b AND XO-1b USING THE WIDE FIELD CAMERA-3 ON THE HUBBLE SPACE TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Deming, Drake; Wilkins, Ashlee [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); McCullough, Peter; Crouzet, Nicolas [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Burrows, Adam [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544-1001 (United States); Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Agol, Eric; Dobbs-Dixon, Ian [NASA Astrobiology Institute' s Virtual Planetary Laboratory (United States); Madhusudhan, Nikku [Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06511 (United States); Desert, Jean-Michel; Knutson, Heather A.; Line, Michael [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Gilliland, Ronald L. [Center for Exoplanets and Habitable Worlds, The Pennsylvania State University, University Park, PA 16802 (United States); Haynes, Korey [Department of Physics and Astronomy, George Mason University, Fairfax, VA 22030 (United States); Magic, Zazralt [Max-Planck-Institut fuer Astrophysik, D-85741 Garching (Germany); Mandell, Avi M.; Clampin, Mark [NASA' s Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Ranjan, Sukrit; Charbonneau, David [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Seager, Sara, E-mail: ddeming@astro.umd.edu [Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); and others

    2013-09-10

    Exoplanetary transmission spectroscopy in the near-infrared using the Hubble Space Telescope (HST) NICMOS is currently ambiguous because different observational groups claim different results from the same data, depending on their analysis methodologies. Spatial scanning with HST/WFC3 provides an opportunity to resolve this ambiguity. We here report WFC3 spectroscopy of the giant planets HD 209458b and XO-1b in transit, using spatial scanning mode for maximum photon-collecting efficiency. We introduce an analysis technique that derives the exoplanetary transmission spectrum without the necessity of explicitly decorrelating instrumental effects, and achieves nearly photon-limited precision even at the high flux levels collected in spatial scan mode. Our errors are within 6% (XO-1) and 26% (HD 209458b) of the photon-limit at a resolving power of {lambda}/{delta}{lambda} {approx} 70, and are better than 0.01% per spectral channel. Both planets exhibit water absorption of approximately 200 ppm at the water peak near 1.38 {mu}m. Our result for XO-1b contradicts the much larger absorption derived from NICMOS spectroscopy. The weak water absorption we measure for HD 209458b is reminiscent of the weakness of sodium absorption in the first transmission spectroscopy of an exoplanet atmosphere by Charbonneau et al. Model atmospheres having uniformly distributed extra opacity of 0.012 cm{sup 2} g{sup -1} account approximately for both our water measurement and the sodium absorption. Our results for HD 209458b support the picture advocated by Pont et al. in which weak molecular absorptions are superposed on a transmission spectrum that is dominated by continuous opacity due to haze and/or dust. However, the extra opacity needed for HD 209458b is grayer than for HD 189733b, with a weaker Rayleigh component.

  8. Mothers of Invention: Hubble Engineers Push Robotic 'Evolution' to Save Telescope, Enable New Exploration

    Science.gov (United States)

    Morring, Frank, Jr.

    2004-01-01

    Robotic technology being developed out of necessity to keep the Hubble Space Telescope operating could also lead to new levels of man-machine team-work in deep-space exploration down the road-if it survives the near-term scramble for funding. Engineers here who have devoted their NASA careers to the concept of humans servicing the telescope in orbit are planning modifications to International Space Station (ISS) robots that would leave the humans on the ground. The work. forced by post-Columbia flight rules that killed a planned shuttle-servicing mission to Hubble, marks another step in the evolution of robot-partners for human space explorers. "Hubble has always been a pathfider for this agency," says Mike Weiss. Hubble deputy program manager technical. "When the space station was flown and assembled, Hubble was the pathfinder. not just for modularity, but for operations, for assembly techniques. Exploration is the next step. Things we're going to do on Hubble are going to be applied to exploration. It's not just putting a robot in space. It's operating a robot in space. It's adapting that robot to what needs to be done the next time you're up there."

  9. Astrometry With the Hubble Space Telescope: Trigonometric Parallaxes of Planetary Nebula Nuclei NGC 6853, NGC 7293, ABELL 31, and DeHt 5

    Science.gov (United States)

    Benedict, G. F.; McArthur, Barbara E.; Napiwotzki, Ralf; Harrison, Thomas E.; Harris, Hugh C.; Nelan, Edmund; Bond, Howard E; Patterson, Richard J.; Ciardullo, Robin

    2009-01-01

    We present absolute parallaxes and relative proper motions for the central stars of the planetary nebulae NGC 6853 (The Dumbbell), NGC 7293 (The Helix), Abell 31, and DeHt 5. This paper details our reduction and analysis using DeHt 5 as an example. We obtain these planetary nebula nuclei (PNNi) parallaxes with astrometric data from Fine Guidance Sensors FGS 1r and FGS 3, white-light interferometers on the Hubble Space Telescope. Proper motions, spectral classifications and VJHKT2M and DDO51 photometry of the stars comprising the astrometric reference frames provide spectrophotometric estimates of reference star absolute parallaxes. Introducing these into our model as observations with error, we determine absolute parallaxes for each PNN. Weighted averaging with previous independent parallax measurements yields an average parallax precision, sigma (sub pi)/ pi = 5%. Derived distances are: d(sub NGC6853) = 405(exp +28 sub -25) pc, d(sub NGC7293) = 216(exp +14 sub -12) pc, d(sub Abell31) = 621(exp +91 sub -70) pc, and d(sub DeHt5) = 345(exp +19 sub -17) pc. These PNNi distances are all smaller than previously derived from spectroscopic analyses of the central stars. To obtain absolute magnitudes from these distances requires estimates of interstellar extinction. We average extinction measurements culled from the literature, from reddening based on PNNi intrinsic colors derived from model SEDs, and an assumption that each PNN experiences the same rate of extinction as a function of distance as do the reference stars nearest (in angular separation) to each central star. We also apply Lutz-Kelker bias corrections. The absolute magnitudes and effective temperatures permit estimates of PNNi radii through both the Stefan-Boltzmann relation and Eddington fluxes. Comparing absolute magnitudes with post-AGB models provides mass estimates. Masses cluster around 0.57 solar Mass, close to the peak of the white dwarf mass distribution. Adding a few more PNNi with well

  10. A PANCHROMATIC CATALOG OF EARLY-TYPE GALAXIES AT INTERMEDIATE REDSHIFT IN THE HUBBLE SPACE TELESCOPE WIDE FIELD CAMERA 3 EARLY RELEASE SCIENCE FIELD

    Energy Technology Data Exchange (ETDEWEB)

    Rutkowski, M. J.; Cohen, S. H.; Windhorst, R. A. [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1404 (United States); Kaviraj, S.; Crockett, R. M.; Silk, J. [Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); O' Connell, R. W. [Department of Astronomy, University of Virginia, P.O. Box 3818, Charlottesville, VA 22903 (United States); Hathi, N. P.; McCarthy, P. J. [Observatories of the Carnegie Institute of Washington, Pasadena, CA 91101 (United States); Ryan, R. E. Jr.; Koekemoer, A.; Bond, H. E. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Yan, H. [Center for Cosmology and Astroparticle Physics, Ohio State University, Columbus, OH 43210 (United States); Kimble, R. A. [NASA-Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Balick, B. [Department of Astronomy, University of Washington, Seattle, WA 98195-1580 (United States); Calzetti, D. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Disney, M. J. [School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA (United Kingdom); Dopita, M. A. [Research School of Physics and Astronomy, The Australian National University, ACT 2611 (Australia); Frogel, J. A. [Astronomy Department, King Abdulaziz University, P.O. Box 80203, Jeddah (Saudi Arabia); Hall, D. N. B. [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States); and others

    2012-03-01

    In the first of a series of forthcoming publications, we present a panchromatic catalog of 102 visually selected early-type galaxies (ETGs) from observations in the Early Release Science (ERS) program with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) of the Great Observatories Origins Deep Survey-South (GOODS-S) field. Our ETGs span a large redshift range, 0.35 {approx}< z {approx}< 1.5, with each redshift spectroscopically confirmed by previous published surveys of the ERS field. We combine our measured WFC3 ERS and Advanced Camera for Surveys (ACS) GOODS-S photometry to gain continuous sensitivity from the rest-frame far-UV to near-IR emission for each ETG. The superior spatial resolution of the HST over this panchromatic baseline allows us to classify the ETGs by their small-scale internal structures, as well as their local environment. By fitting stellar population spectral templates to the broadband photometry of the ETGs, we determine that the average masses of the ETGs are comparable to the characteristic stellar mass of massive galaxies, 10{sup 11} < M{sub *}[M{sub Sun }]<10{sup 12}. By transforming the observed photometry into the Galaxy Evolution Explorer FUV and NUV, Johnson V, and Sloan Digital Sky Survey g' and r' bandpasses we identify a noteworthy diversity in the rest-frame UV-optical colors and find the mean rest-frame (FUV-V) = 3.5 and (NUV-V) = 3.3, with 1{sigma} standard deviations {approx_equal}1.0. The blue rest-frame UV-optical colors observed for most of the ETGs are evidence for star formation during the preceding gigayear, but no systems exhibit UV-optical photometry consistent with major recent ({approx}<50 Myr) starbursts. Future publications which address the diversity of stellar populations likely to be present in these ETGs, and the potential mechanisms by which recent star formation episodes are activated, are discussed.

  11. Hubble space telescope grism spectroscopy of extreme starbursts across cosmic time: The role of dwarf galaxies in the star formation history of the universe

    Energy Technology Data Exchange (ETDEWEB)

    Atek, Hakim; Kneib, Jean-Paul [Laboratoire d' Astrophysique, EPFL, CH-1290 Sauverny (Switzerland); Pacifici, Camilla [Yonsei University Observatory, Yonsei University, Seoul 120-749 (Korea, Republic of); Malkan, Matthew; Ross, Nathaniel [Department of Physics and Astronomy, University of California, Los Angeles, CA (United States); Charlot, Stephane; Lehnert, Matthew [UPMC-CNRS, UMR7095, Institut d' Astrophysique de Paris, F-75014 Paris (France); Lee, Janice [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Bedregal, Alejandro [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States); Bunker, Andrew J. [Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, OX13RH (United Kingdom); Colbert, James W.; Rafelski, Marc [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Dressler, Alan; McCarthy, Patrick [Observatories of the Carnegie Institution for Science, Pasadena, CA 91101 (United States); Hathi, Nimish [Aix Marseille Université, CNRS, LAM (Laboratoire d' Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France); Martin, Crystal L. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Siana, Brian [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Teplitz, Harry I. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States)

    2014-07-10

    Near infrared slitless spectroscopy with the Wide Field Camera 3, on board the Hubble Space Telescope, offers a unique opportunity to study low-mass galaxy populations at high redshift (z ∼ 1-2). While most high-z surveys are biased toward massive galaxies, we are able to select sources via their emission lines that have very faint continua. We investigate the star formation rate (SFR)-stellar mass (M{sub *}) relation for about 1000 emission line galaxies identified over a wide redshift range of 0.3 ≲ z ≲ 2.3. We use the Hα emission as an accurate SFR indicator and correct the broadband photometry for the strong nebular contribution to derive accurate stellar masses down to M{sub *} ∼10{sup 7} M{sub ☉}. We focus here on a subsample of galaxies that show extremely strong emission lines (EELGs) with rest-frame equivalent widths ranging from 200 to 1500 Å. This population consists of outliers to the normal SFR-M{sub *} sequence with much higher specific SFRs (>10 Gyr{sup –1}). While on-sequence galaxies follow continuous star formation processes, EELGs are thought to be caught during an extreme burst of star formation that can double their stellar mass in a period of less than 100 Myr. The contribution of the starburst population to the total star formation density appears to be larger than what has been reported for more massive galaxies in previous studies. In the complete mass range 8.2 < log(M{sub *}/M{sub ☉}) <10 and a SFR lower completeness limit of about 2 M{sub ☉} yr{sup –1} (10 M{sub ☉} yr{sup –1}) at z ∼ 1 (z ∼ 2), we find that starbursts having EW{sub rest}(Hα) > 300, 200, and 100 Å contribute up to ∼13%, 18%, and 34%, respectively, to the total SFR of emission-line-selected sample at z ∼ 1-2. The comparison with samples of massive galaxies shows an increase in the contribution of starbursts toward lower masses.

  12. Structure and density of Callisto's atmosphere from a fluid-kinetic model of its ionosphere: Comparison with Hubble Space Telescope and Galileo observations

    Science.gov (United States)

    Hartkorn, Oliver; Saur, Joachim; Strobel, Darrell F.

    2017-01-01

    We develop a model of the ionospheric electron population of Jupiter's moon Callisto using a prescribed neutral atmosphere composed of O2, CO2 and H2O. A kinetic description of ionospheric suprathermal electrons coupled with a fluid description of ionospheric thermal electrons is well suited to jointly analyze and interpret observations of electron density and atmospheric UV emission. Accordingly, we calculate the electron energy distribution function at each point in the ionosphere by solving a coupled set of equations consisting of the Boltzmann equation for suprathermal electrons and the continuity and energy equation for thermal electrons. We assume a stationary balance between local sources and sinks of electrons and electron energy. Electron transport within the ionosphere is neglected, since collision time scales are shorter than transport time scales in the region of Callisto's ionosphere where the major concentrations of electrons is located and the major part of the atmospheric UV emission is generated. We consider photoionization, which is the dominant ionospheric electron source, and secondary ionization from collisions of photoelectrons with neutrals. Our calculations yield electron densities and electron impact generated UV emissions from Callisto's atmosphere. Comparing our modeled UV emission intensities with the Hubble Space Telescope observation of Cunningham et al. (2015) , we find that Callisto's atmosphere has a mean O2 column density of 2.1-1.1+1.1 ×1019 m-2. A joint comparison with this HST observation and radio occultation observations of Kliore et al. (2002) shows that Callisto's atmosphere possesses a day night asymmetry. We derive terminator O2 column densities of ∼ 0.4 × 1019 m-2 , for which we find subsolar O2 column densities in the range of 2.4 - 9.8 ×1019 m-2. Our calculations also show that the electron density is very sensitive to the relative abundance of H2O due to the thermal electron cooling by rotational state excitation

  13. THE STRUCTURE OF NUCLEAR STAR CLUSTERS IN NEARBY LATE-TYPE SPIRAL GALAXIES FROM HUBBLE SPACE TELESCOPE WIDE FIELD CAMERA 3 IMAGING

    Energy Technology Data Exchange (ETDEWEB)

    Carson, Daniel J.; Barth, Aaron J. [Department of Physics and Astronomy, University of California Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697 (United States); Seth, Anil C.; Brok, Mark den [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Cappellari, Michele [Sub-Department of Astrophysics, Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Greene, Jenny E. [Department of Astrophysical Sciences, Princeton University, Peyton Hall—Ivy Lane, Princeton, NJ 08544 (United States); Ho, Luis C. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Neumayer, Nadine [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany)

    2015-05-15

    We obtained Hubble Space Telescope/Wide Field Camera 3 imaging of a sample of ten of the nearest and brightest nuclear clusters (NCs) residing in late-type spiral galaxies, in seven bands that span the near-UV to the near-IR. Structural properties of the clusters were measured by fitting two-dimensional surface brightness profiles to the images using GALFIT. The clusters exhibit a wide range of structural properties, with F814W absolute magnitudes that range from −11.2 to −15.1 mag and F814W effective radii that range from 1.4 to 8.3 pc. For 6 of the 10 clusters in our sample, we find changes in the effective radius with wavelength, suggesting radially varying stellar populations. In four of the objects, the effective radius increases with wavelength, indicating the presence of a younger population that is more concentrated than the bulk of the stars in the cluster. However, we find a general decrease in effective radius with wavelength in two of the objects in our sample, which may indicate extended, circumnuclear star formation. We also find a general trend of increasing roundness of the clusters at longer wavelengths, as well as a correlation between the axis ratios of the NCs and their host galaxies. These observations indicate that blue disks aligned with the host galaxy plane are a common feature of NCs in late-type galaxies, but are difficult to detect in galaxies that are close to face-on. In color–color diagrams spanning the near-UV through the near-IR, most of the clusters lie far from single-burst evolutionary tracks, showing evidence for multi-age populations. Most of the clusters have integrated colors consistent with a mix of an old population (>1 Gyr) and a young population (∼100–300 Myr). The wide wavelength coverage of our data provides a sensitivity to populations with a mix of ages that would not be possible to achieve with imaging in optical bands only. The surface brightness profiles presented in this work will be used for future

  14. THE HUBBLE SPACE TELESCOPE CLUSTER SUPERNOVA SURVEY. V. IMPROVING THE DARK-ENERGY CONSTRAINTS ABOVE z > 1 AND BUILDING AN EARLY-TYPE-HOSTED SUPERNOVA SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, N.; Rubin, D.; Aldering, G.; Barbary, K.; Faccioli, L.; Fakhouri, H. K. [E.O. Lawrence Berkeley National Lab, Berkeley, CA 94720 (United States); Lidman, C. [Australian Astronomical Observatory, Epping, NSW 1710 (Australia); Amanullah, R.; Botyanszki, J. [Department of Physics, University of California Berkeley, Berkeley, CA 94720 (United States); Barrientos, L. F. [Departamento de Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Santiago (Chile); Brodwin, M. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Connolly, N. [Department of Physics, Hamilton College, Clinton, NY 13323 (United States); Dawson, K. S. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Dey, A. [National Optical Astronomy Observatory, Tucson, AZ 85726-6732 (United States); Doi, M. [Institute of Astronomy, Graduate School of Science, University of Tokyo 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Donahue, M. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Deustua, S. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Eisenhardt, P. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Ellingson, E. [Center for Astrophysics and Space Astronomy, 389 UCB, University of Colorado, Boulder, CO 80309 (United States); Fadeyev, V., E-mail: nsuzuki@lbl.gov, E-mail: rubind@berkeley.edu, E-mail: clidman@aao.gov.au [Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz, CA 94064 (United States); Collaboration: Supernova Cosmology Project; and others

    2012-02-10

    We present Advanced Camera for Surveys, NICMOS, and Keck adaptive-optics-assisted photometry of 20 Type Ia supernovae (SNe Ia) from the Hubble Space Telescope (HST) Cluster Supernova Survey. The SNe Ia were discovered over the redshift interval 0.623 < z < 1.415. Of these SNe Ia, 14 pass our strict selection cuts and are used in combination with the world's sample of SNe Ia to derive the best current constraints on dark energy. Of our new SNe Ia, 10 are beyond redshift z = 1, thereby nearly doubling the statistical weight of HST-discovered SNe Ia beyond this redshift. Our detailed analysis corrects for the recently identified correlation between SN Ia luminosity and host galaxy mass and corrects the NICMOS zero point at the count rates appropriate for very distant SNe Ia. Adding these SNe improves the best combined constraint on dark-energy density, {rho}{sub DE}(z), at redshifts 1.0 < z < 1.6 by 18% (including systematic errors). For a flat {Lambda}CDM universe, we find {Omega}{sub {Lambda}} = 0.729 {+-} 0.014 (68% confidence level (CL) including systematic errors). For a flat wCDM model, we measure a constant dark-energy equation-of-state parameter w = -1.013{sup +0.068}{sub -0.073} (68% CL). Curvature is constrained to {approx}0.7% in the owCDM model and to {approx}2% in a model in which dark energy is allowed to vary with parameters w{sub 0} and w{sub a} . Further tightening the constraints on the time evolution of dark energy will require several improvements, including high-quality multi-passband photometry of a sample of several dozen z > 1 SNe Ia. We describe how such a sample could be efficiently obtained by targeting cluster fields with WFC3 on board HST. The updated supernova Union2.1 compilation of 580 SNe is available at http://supernova.lbl.gov/Union.

  15. An Extensive Census of Hubble Space Telescope Counterparts to Chandra X-Ray Sources in the Globular Cluster 47 Tucanae. II. Time Series and Analysis

    Science.gov (United States)

    Edmonds, Peter D.; Gilliland, Ronald L.; Heinke, Craig O.; Grindlay, Jonathan E.

    2003-10-01

    ) studies by Albrow et al. The X-ray properties of these objects (luminosity, hardness ratios, and variability) are consistent with those of active binaries found in field studies, and the FX/Fopt distribution is significantly different from those of the CVs and the MSPs that are detected (or possibly detected) in the optical. Despite these results, we examine the possibility that a few of the active binaries are MSPs with main-sequence companions resulting from double exchanges in the crowded core of 47 Tuc. No solid evidence is found for a significant population of such objects, and therefore, using the methods of Grindlay et al., we estimate that the number of MSPs in 47 Tuc with luminosities above 1030 ergs s-1 is ~30-40, near the previous lower limit. We present the results of a new, deeper search for faint low-mass X-ray binaries (LMXBs) in quiescence. One reasonable and one marginal candidate for optical identification of a quiescent LMXB was found (one is already known). Finally, it is shown that the periods of the blue variables showing little or no evidence for X-ray emission are too long for Roche lobe filling (if the variations are ellipsoidal). These blue variables also show no evidence for the large flickering levels seen in comparably bright CVs. At present we have no satisfactory explanation for these objects, although some may be detached white dwarf-main-sequence star binaries. Based on observations with the NASA/ESA Hubble Space Telescope obtained at STScI, which is operated by AURA, Inc. under NASA contract NAS 5-26555.

  16. The NASA Spitzer Space Telescope.

    Science.gov (United States)

    Gehrz, R D; Roellig, T L; Werner, M W; Fazio, G G; Houck, J R; Low, F J; Rieke, G H; Soifer, B T; Levine, D A; Romana, E A

    2007-01-01

    The National Aeronautics and Space Administration's Spitzer Space Telescope (formerly the Space Infrared Telescope Facility) is the fourth and final facility in the Great Observatories Program, joining Hubble Space Telescope (1990), the Compton Gamma-Ray Observatory (1991-2000), and the Chandra X-Ray Observatory (1999). Spitzer, with a sensitivity that is almost three orders of magnitude greater than that of any previous ground-based and space-based infrared observatory, is expected to revolutionize our understanding of the creation of the universe, the formation and evolution of primitive galaxies, the origin of stars and planets, and the chemical evolution of the universe. This review presents a brief overview of the scientific objectives and history of infrared astronomy. We discuss Spitzer's expected role in infrared astronomy for the new millennium. We describe pertinent details of the design, construction, launch, in-orbit checkout, and operations of the observatory and summarize some science highlights from the first two and a half years of Spitzer operations. More information about Spitzer can be found at http://spitzer.caltech.edu/.

  17. The James Webb Space Telescope

    Science.gov (United States)

    Gardner, Jonathan P.

    2011-01-01

    The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes, and is currently the largest scientific project under construction in the United States. It will be a large (6.6m) cold (50K) telescope launched into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. Science with the James Webb Space Telescope falls into four themes. The End of the Dark Ages: First Light and Reionization theme seeks to identify the first luminous sources to form and to determine the ionization history of the universe. The Assembly of Galaxies theme seeks to determine how galaxies and the dark matter, gas, stars, metals, morphological structures, and black holes within them evolved from the epoch of reionization to the present. The Birth of Stars and Protoplanetary Systems theme seeks to unravel the birth and early evolution of stars, from infall onto dust-enshrouded protostars, to the genesis of planetary systems. The Planetary Systems and the Origins of Life theme seeks to determine the physical and chemical properties of planetary systems around nearby stars and of our own, and investigate the potential for life in those systems. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. I will conclude the talk with a description of recent technical progress in the construction of the observatory.

  18. Optical Space Telescope Assembly Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Optical Space Telescope Assembly (OSTA) task is to demonstrate the technology readiness of assembling large space telescopes on orbit in 2015. This task is an...

  19. High-Performance Reaction Wheel Optimization for Fine-Pointing Space Platforms: Minimizing Induced Vibration Effects on Jitter Performance plus Lessons Learned from Hubble Space Telescope for Current and Future Spacecraft Applications

    Science.gov (United States)

    Hasha, Martin D.

    2016-01-01

    The Hubble Space Telescope (HST) applies large-diameter optics (2.5-m primary mirror) for diffraction-limited resolution spanning an extended wavelength range (approx. 100-2500 nm). Its Pointing Control System (PCS) Reaction Wheel Assemblies (RWAs), in the Support Systems Module (SSM), acquired an unprecedented set of high-sensitivity Induced Vibration (IV) data for 5 flight-certified RWAs: dwelling at set rotation rates. Focused on 4 key ratios, force and moment harmonic values (in 3 local principal directions) are extracted in the RWA operating range (0-3000 RPM). The IV test data, obtained under ambient lab conditions, are investigated in detail, evaluated, compiled, and curve-fitted; variational trends, core causes, and unforeseen anomalies are addressed. In aggregate, these values constitute a statistically-valid basis to quantify ground test-to-test variations and facilitate extrapolations to on-orbit conditions. Accumulated knowledge of bearing-rotor vibrational sources, corresponding harmonic contributions, and salient elements of IV key variability factors are discussed. An evolved methodology is presented for absolute assessments and relative comparisons of macro-level IV signal magnitude due to micro-level construction-assembly geometric details/imperfections stemming from both electrical drive and primary bearing design parameters. Based upon studies of same-size/similar-design momentum wheels' IV changes, upper estimates due to transitions from ground tests to orbital conditions are derived. Recommended HST RWA choices are discussed relative to system optimization/tradeoffs of Line-Of-Sight (LOS) vector-pointing focal-plane error driven by higher IV transmissibilities through low-damped structural dynamics that stimulate optical elements. Unique analytical disturbance results for orbital HST accelerations are described applicable to microgravity efforts. Conclusions, lessons learned, historical context/insights, and perspectives on future applications

  20. Origins Space Telescope

    Science.gov (United States)

    Cooray, Asantha R.; Origins Space Telescope Study Team

    2017-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its spectrographs will enable 3D surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu. I will summarize the OST STDT, mission design and instruments, key science drivers, and the study plan over the next two years.

  1. Deep space telescopes

    CERN Document Server

    CERN. Geneva

    2006-01-01

    The short series of seminars will address results and aims of current and future space astrophysics as the cultural framework for the development of deep space telescopes. It will then present such new tools, as they are currently available to, or imagined by, the scientific community, in the context of the science plans of ESA and of all major world space agencies. Ground-based astronomy, in the 400 years since Galileo’s telescope, has given us a profound phenomenological comprehension of our Universe, but has traditionally been limited to the narrow band(s) to which our terrestrial atmosphere is transparent. Celestial objects, however, do not care about our limitations, and distribute most of the information about their physics throughout the complete electromagnetic spectrum. Such information is there for the taking, from millimiter wavelengths to gamma rays. Forty years astronomy from space, covering now most of the e.m. spectrum, have thus given us a better understanding of our physical Universe then t...

  2. IMF dependence of the open-closed field line boundary in Saturn's ionosphere, and its relation to the UV auroral oval observed by the Hubble Space Telescope

    Directory of Open Access Journals (Sweden)

    E. S. Belenkaya

    2007-06-01

    Full Text Available We study the dependence of Saturn's magnetospheric magnetic field structure on the interplanetary magnetic field (IMF, together with the corresponding variations of the open-closed field line boundary in the ionosphere. Specifically we investigate the interval from 8 to 30 January 2004, when UV images of Saturn's southern aurora were obtained by the Hubble Space Telescope (HST, and simultaneous interplanetary measurements were provided by the Cassini spacecraft located near the ecliptic ~0.2 AU upstream of Saturn and ~0.5 AU off the planet-Sun line towards dawn. Using the paraboloid model of Saturn's magnetosphere, we calculate the magnetospheric magnetic field structure for several values of the IMF vector representative of interplanetary compression regions. Variations in the magnetic structure lead to different shapes and areas of the open field line region in the ionosphere. Comparison with the HST auroral images shows that the area of the computed open flux region is generally comparable to that enclosed by the auroral oval, and sometimes agrees in detail with its poleward boundary, though more typically being displaced by a few degrees in the tailward direction.

  3. The Emergent 1.1-1.7 Micron Spectrum of the Exoplanet CoRoT-2b as Measured Using the Hubble Space Telescope

    CERN Document Server

    Wilkins, Ashlee; Madhusudhan, Nikku; Burrows, Adam; Knutson, Heather; McCullough, Peter; Ranjan, Sukrit

    2014-01-01

    We have used Hubble/WFC3 and the G141 grism to measure the secondary eclipse of the transiting very hot Jupiter CoRoT-2b in the 1.1-1.7$\\mu$m spectral region. We find an eclipse depth averaged over this band equal to $395^{+69}_{-45}$ parts per million, equivalent to a blackbody temperature of $1788\\pm18$K. We study and characterize several WFC3 instrumental effects, especially the "hook" phenomenon described by Deming et al. (2013). We use data from several transiting exoplanet systems to find a quantitative relation between the amplitude of the hook and the exposure level of a given pixel. Although the uncertainties in this relation are too large to allow us to develop an empirical correction for our data, our study provides a useful guide for optimizing exposure levels in future WFC3 observations. We derive the planet's spectrum using a differential method. The planet-to-star contrast increases to longer wavelength within the WFC3 bandpass, but without water absorption or emission to a $3\\sigma$ limit of 8...

  4. Neutral Buoyancy Simulator- NB38 -Space Telescope

    Science.gov (United States)

    1980-01-01

    The Hubble Space Telescope (HST) is a cooperative program of the European Space Agency (ESA) and the National Aeronautical and Space Administration (NASA) to operate a long-lived space-based observatory. It was the flagship mission of NASA's Great Observatories program. The HST program began as an astronomical dream in the 1940s. During the 1970s and 1980s, the HST was finally designed and built becoming operational in the 1990s. The HST was deployed into a low-Earth orbit on April 25, 1990 from the cargo bay of the Space Shuttle Discovery (STS-31). The design of the HST took into consideration its length of service and the necessity of repairs and equipment replacement by making the body modular. In doing so, subsequent shuttle missions could recover the HST, replace faulty or obsolete parts and be re-released. Pictured is MSFC's Neutral Buoyancy Simulator (NBS) that served as the test center for shuttle astronauts training for Hubble related missions. Shown are astronauts Bruce McCandless and Sharnon Lucid being fitted for their space suits prior to entering the NBS to begin training on the space telescope axial scientific instrument changeout.

  5. Neutral Buoyancy Simulator- NB38 -Space Telescope

    Science.gov (United States)

    1980-01-01

    The Hubble Space Telescope (HST) is a cooperative program of the European Space Agency (ESA) and the National Aeronautical and Space Administration (NASA) to operate a long-lived space-based observatory. It was the flagship mission of NASA's Great Observatories program. The HST program began as an astronomical dream in the 1940s. During the 1970s and 1980s, the HST was finally designed and built becoming operational in the 1990s. The HST was deployed into a low-Earth orbit on April 25, 1990 from the cargo bay of the Space Shuttle Discovery (STS-31). The design of the HST took into consideration its length of service and the necessity of repairs and equipment replacement by making the body modular. In doing so, subsequent shuttle missions could recover the HST, replace faulty or obsolete parts and be re-released. Pictured is MSFC's Neutral Buoyancy Simulator (NBS) that served as the test center for shuttle astronauts training for Hubble related missions. Shown are astronauts Bruce McCandless and Sharnon Lucid being fitted for their space suits prior to entering the NBS to begin training on the space telescope axial scientific instrument changeout.

  6. Progress in Space Solar Telescope

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper we will summarize the progress in the development of the Chinese Space Solar Telescope (SST) during the past few years. The main scientific objective of SST is to observe the fundamental structure of solar magnetic field with its 1-m optical telescope. The success of 1-m Swedish Solar Telescope and Hinode underscores the importance of this 1-m space telescope. In addition, some key technical problems have been solved.

  7. The emergent 1.1-1.7 μm spectrum of the exoplanet COROT-2B as measured using the Hubble space telescope

    Energy Technology Data Exchange (ETDEWEB)

    Wilkins, Ashlee N.; Deming, Drake [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Madhusudhan, Nikku [Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06511 (United States); Burrows, Adam [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544-1001 (United States); Knutson, Heather [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); McCullough, Peter [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Ranjan, Sukrit, E-mail: awilkins@astro.umd.edu [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2014-03-10

    We have used Hubble/WFC3 and the G141 grism to measure the secondary eclipse of the transiting, very hot Jupiter CoRoT-2b in the 1.1-1.7 μm spectral region. We find an eclipse depth averaged over this band equal to 395{sub −45}{sup +69} parts per million, equivalent to a blackbody temperature of 1788 ± 18 K. We study and characterize several WFC3 instrumental effects, especially the 'hook' phenomenon described by Deming et al. We use data from several transiting exoplanet systems to find a quantitative relation between the amplitude of the hook and the exposure level of a given pixel. Although the uncertainties in this relation are too large to allow us to develop an empirical correction for our data, our study provides a useful guide for optimizing exposure levels in future WFC3 observations. We derive the planet's spectrum using a differential method. The planet-to-star contrast increases to longer wavelength within the WFC3 bandpass, but without water absorption or emission to a 3σ limit of 85 ppm. The slope of the WFC3 spectrum is significantly less than the slope of the best-fit blackbody. We compare all existing eclipse data for this planet to a blackbody spectrum, and to spectra from both solar abundance and carbon-rich (C/O = 1) models. A blackbody spectrum is an acceptable fit to the full data set. Extra continuous opacity due to clouds or haze, and flattened temperature profiles, are strong candidates to produce quasi-blackbody spectra, and to account for the amplitude of the optical eclipses. Our results show ambiguous evidence for a temperature inversion in this planet.

  8. Space-compatible strain gauges as an integration aid for the James Webb Space Telescope Mid-Infrared Instrument

    DEFF Research Database (Denmark)

    Samara-Ratna, Piyal; Sykes, Jon; Bicknell, Chris

    2015-01-01

    in operation. The Mid-Infrared Instrument is one of four instruments to be used on the James Webb Space Telescope which is due for launch in 2018. This telescope will be successor to the Hubble Space Telescope and is the largest space-based astronomy project ever to be conceived. Critical to operation...

  9. Spectroradiometry with Space Telescopes

    CERN Document Server

    Pauluhn, Anuschka; Smith, Peter L; Colina, Luis

    2015-01-01

    Radiometry has been of fundamental importance in astronomy from the early beginnings. Initially, astronomers had their own radiometric system, based on extraterrestrial standards, namely the irradiance of stars expressed in visual magnitudes. Observing and comparing magnitudes in specific spectral bands then led to the astronomical spectrophotometry. The advent of astronomical high-resolution spectroscopy offered the possibility to interpret observations through physical models of stellar atmospheres. Such models had to be constructed based on physics-related units, and such units, rather than magnitudes, were then used for observational tests of the models. In this review, we provide an overview of how to achieve a valid laboratory calibration, and discuss ways to reliably extend this calibration to the spectroscopic telescope's performance in space. Recently, the quest for independent calibrations traceable to laboratory standards has become a well-supported aim, and has led to plans for now also launching ...

  10. The R136 star cluster dissected with Hubble Space Telescope/STIS. I. Far-ultraviolet spectroscopic census and the origin of He II λ1640 in young star clusters

    Science.gov (United States)

    Crowther, Paul A.; Caballero-Nieves, S. M.; Bostroem, K. A.; Maíz Apellániz, J.; Schneider, F. R. N.; Walborn, N. R.; Angus, C. R.; Brott, I.; Bonanos, A.; de Koter, A.; de Mink, S. E.; Evans, C. J.; Gräfener, G.; Herrero, A.; Howarth, I. D.; Langer, N.; Lennon, D. J.; Puls, J.; Sana, H.; Vink, J. S.

    2016-05-01

    We introduce a Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) stellar census of R136a, the central ionizing star cluster of 30 Doradus. We present low resolution far-ultraviolet STIS spectroscopy of R136 using 17 contiguous 52 arcsec × 0.2 arcsec slits which together provide complete coverage of the central 0.85 parsec (3.4 arcsec). We provide spectral types of 90 per cent of the 57 sources brighter than mF555W = 16.0 mag within a radius of 0.5 parsec of R136a1, plus 8 additional nearby sources including R136b (O4 If/WN8). We measure wind velocities for 52 early-type stars from C IVλλ1548-51, including 16 O2-3 stars. For the first time, we spectroscopically classify all Weigelt and Baier members of R136a, which comprise three WN5 stars (a1-a3), two O supergiants (a5-a6) and three early O dwarfs (a4, a7, a8). A complete Hertzsprung-Russell diagram for the most massive O stars in R136 is provided, from which we obtain a cluster age of 1.5^{+0.3}_{-0.7} Myr. In addition, we discuss the integrated ultraviolet spectrum of R136, and highlight the central role played by the most luminous stars in producing the prominent He II λ1640 emission line. This emission is totally dominated by very massive stars with initial masses above ˜100 M⊙. The presence of strong He II λ1640 emission in the integrated light of very young star clusters (e.g. A1 in NGC 3125) favours an initial mass function extending well beyond a conventional upper limit of 100 M⊙. We include montages of ultraviolet spectroscopy for Large Magellanic Cloud O stars in the appendix. Future studies in this series will focus on optical STIS medium resolution observations.

  11. Near-infrared transmission spectrum of the warm-uranus GJ 3470b with the Wide Field Camera-3 on the Hubble Space Telescope

    CERN Document Server

    Ehrenreich, David; Lovis, Christophe; Delfosse, Xavier; Forveille, Thierry; Mayor, Michel; Neves, Vasco; Santos, Nuno C; Udry, Stéphane; Ségransan, Damien

    2014-01-01

    The atmospheric composition of low-mass exoplanets is the object of intense observational and theoretical investigations. GJ3470b is a warm uranus recently detected in transit across a bright late-type star. The transit of this planet has already been observed in several band passes from the ground and space, allowing observers to draw an intriguing yet incomplete transmission spectrum of the planet atmospheric limb. In particular, published data in the visible suggest the existence of a Rayleigh scattering slope, making GJ3470b a unique case among the known neptunes, while data obtained beyond 2 um are consistent with a flat infrared spectrum. The unexplored near-infrared spectral region between 1 and 2 um, is thus key to undertanding the atmospheric nature of GJ3470b. Here, we report on the first space-borne spectrum of GJ3470, obtained during one transit of the planet with WFC3 on board HST, operated in stare mode. The spectrum covers the 1.1--1.7-um region with a resolution of about 300. We retrieve the t...

  12. Hubble Space Telescope Hx Imaging of Star-forming Galaxies at z approximately equal to 1-1.5: Evolution in the Size and Luminosity of Giant H II Regions

    Science.gov (United States)

    Livermore, R. C.; Jones, T.; Richard, J.; Bower, R. G.; Ellis, R. S.; Swinbank, A. M.; Rigby, J. R.; Smail, Ian; Arribas, S.; Rodriguez-Zaurin, J.; hide

    2013-01-01

    We present Hubble Space Telescope/Wide Field Camera 3 narrow-band imaging of the Ha emission in a sample of eight gravitationally lensed galaxies at z = 1-1.5. The magnification caused by the foreground clusters enables us to obtain a median source plane spatial resolution of 360 pc, as well as providing magnifications in flux ranging from approximately 10× to approximately 50×. This enables us to identify resolved star-forming HII regions at this epoch and therefore study their Ha luminosity distributions for comparisons with equivalent samples at z approximately 2 and in the local Universe. We find evolution in the both luminosity and surface brightness of HII regions with redshift. The distribution of clump properties can be quantified with an HII region luminosity function, which can be fit by a power law with an exponential break at some cut-off, and we find that the cut-off evolves with redshift. We therefore conclude that 'clumpy' galaxies are seen at high redshift because of the evolution of the cut-off mass; the galaxies themselves follow similar scaling relations to those at z = 0, but their HII regions are larger and brighter and thus appear as clumps which dominate the morphology of the galaxy. A simple theoretical argument based on gas collapsing on scales of the Jeans mass in a marginally unstable disc shows that the clumpy morphologies of high-z galaxies are driven by the competing effects of higher gas fractions causing perturbations on larger scales, partially compensated by higher epicyclic frequencies which stabilize the disc.

  13. DUST EXTINCTION FROM BALMER DECREMENTS OF STAR-FORMING GALAXIES AT 0.75 {<=} z {<=} 1.5 WITH HUBBLE SPACE TELESCOPE/WIDE-FIELD-CAMERA 3 SPECTROSCOPY FROM THE WFC3 INFRARED SPECTROSCOPIC PARALLEL SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez, A.; Siana, B.; Masters, D. [Department of Physics and Astronomy, University of California Riverside, Riverside, CA 92521 (United States); Henry, A. L.; Martin, C. L. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Scarlata, C.; Bedregal, A. G. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States); Malkan, M.; Ross, N. R. [Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA 90095 (United States); Atek, H.; Colbert, J. W. [Spitzer Science Center, Caltech, Pasadena, CA 91125 (United States); Teplitz, H. I.; Rafelski, M. [Infrared Processing and Analysis Center, Caltech, Pasadena, CA 91125 (United States); McCarthy, P.; Hathi, N. P.; Dressler, A. [Observatories of the Carnegie Institution for Science, Pasadena, CA 91101 (United States); Bunker, A., E-mail: albertod@ucr.edu [Department of Physics, Oxford University, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom)

    2013-02-15

    Spectroscopic observations of H{alpha} and H{beta} emission lines of 128 star-forming galaxies in the redshift range 0.75 {<=} z {<=} 1.5 are presented. These data were taken with slitless spectroscopy using the G102 and G141 grisms of the Wide-Field-Camera 3 (WFC3) on board the Hubble Space Telescope as part of the WFC3 Infrared Spectroscopic Parallel survey. Interstellar dust extinction is measured from stacked spectra that cover the Balmer decrement (H{alpha}/H{beta}). We present dust extinction as a function of H{alpha} luminosity (down to 3 Multiplication-Sign 10{sup 41} erg s{sup -1}), galaxy stellar mass (reaching 4 Multiplication-Sign 10{sup 8} M {sub Sun }), and rest-frame H{alpha} equivalent width. The faintest galaxies are two times fainter in H{alpha} luminosity than galaxies previously studied at z {approx} 1.5. An evolution is observed where galaxies of the same H{alpha} luminosity have lower extinction at higher redshifts, whereas no evolution is found within our error bars with stellar mass. The lower H{alpha} luminosity galaxies in our sample are found to be consistent with no dust extinction. We find an anti-correlation of the [O III] {lambda}5007/H{alpha} flux ratio as a function of luminosity where galaxies with L {sub H{alpha}} < 5 Multiplication-Sign 10{sup 41} erg s{sup -1} are brighter in [O III] {lambda}5007 than H{alpha}. This trend is evident even after extinction correction, suggesting that the increased [O III] {lambda}5007/H{alpha} ratio in low-luminosity galaxies is likely due to lower metallicity and/or higher ionization parameters.

  14. Fate of James Webb Space Telescope murky

    Science.gov (United States)

    Showstack, Randy

    2011-07-01

    The James Webb Space Telescope (JWST), the next-generation successor to the Hubble Space Telescope, was put on the chopping block by the U.S. House of Representatives Appropriations Subcommittee on Commerce, Justice, Science, and Related Agencies. The subcommittee approved a measure on 7 July that “terminates funding for [JWST], which is billions of dollars over budget and plagued by poor management.” Then, on 13 July, Rep. Adam Schiff (D-Calif.), whose district includes NASA's Jet Propulsion Laboratory, tried to insert a funding amendment—transferring $200 million from NASA's Cross-Agency Support budget to JWST—when the full House Committee on Appropriations voted. That amendment failed in a voice vote.

  15. Seismic Imager Space Telescope

    Science.gov (United States)

    Sidick, Erkin; Coste, Keith; Cunningham, J.; Sievers,Michael W.; Agnes, Gregory S.; Polanco, Otto R.; Green, Joseph J.; Cameron, Bruce A.; Redding, David C.; Avouac, Jean Philippe; Ampuero, Jean Paul; Leprince, Sebastien; Michel, Remi

    2012-01-01

    A concept has been developed for a geostationary seismic imager (GSI), a space telescope in geostationary orbit above the Pacific coast of the Americas that would provide movies of many large earthquakes occurring in the area from Southern Chile to Southern Alaska. The GSI movies would cover a field of view as long as 300 km, at a spatial resolution of 3 to 15 m and a temporal resolution of 1 to 2 Hz, which is sufficient for accurate measurement of surface displacements and photometric changes induced by seismic waves. Computer processing of the movie images would exploit these dynamic changes to accurately measure the rapidly evolving surface waves and surface ruptures as they happen. These measurements would provide key information to advance the understanding of the mechanisms governing earthquake ruptures, and the propagation and arrest of damaging seismic waves. GSI operational strategy is to react to earthquakes detected by ground seismometers, slewing the satellite to point at the epicenters of earthquakes above a certain magnitude. Some of these earthquakes will be foreshocks of larger earthquakes; these will be observed, as the spacecraft would have been pointed in the right direction. This strategy was tested against the historical record for the Pacific coast of the Americas, from 1973 until the present. Based on the seismicity recorded during this time period, a GSI mission with a lifetime of 10 years could have been in position to observe at least 13 (22 on average) earthquakes of magnitude larger than 6, and at least one (2 on average) earthquake of magnitude larger than 7. A GSI would provide data unprecedented in its extent and temporal and spatial resolution. It would provide this data for some of the world's most seismically active regions, and do so better and at a lower cost than could be done with ground-based instrumentation. A GSI would revolutionize the understanding of earthquake dynamics, perhaps leading ultimately to effective warning

  16. Large Space Optics: From Hubble to JWST and Beyond

    Science.gov (United States)

    Stahl, H. Philip

    2008-01-01

    If necessity truly is the mother of invention, then advances in lightweight space mirror technology have been driven by launch vehicle mass and volume constraints. In the late 1970 s, at the start of Hubble development, the state of the art in ground based telescopes was 3 to 4 meter monolithic primary mirrors with masses of 6000 to 10,000 kg - clearly too massive for the planned space shuttle 25,000 kg capability to LEO. Necessity led Hubble to a different solution. Launch vehicle mass constraints (and cost) resulted in the development of a 2.4 meter lightweight eggcrate mirror. At 810 kg (180 kg/m2), this mirror was approximately 7.4% of HST s total 11,110 kg mass. And, the total observatory structure at 4.3 m x 13.2 m fit snuggly inside the space shuttle 4.6 m x 18.3 m payload bay. In the early 1990 s, at the start of JWST development, the state of the art in ground based telescopes was 8 meter class monolithic primary mirrors (16,000 to 23,000 kg) and 10 meter segmented mirrors (14,400 kg). Unfortunately, launch vehicles were still constrained to 4.5 meter payloads and 25,000 kg to LEO or 6,600 kg to L2. Furthermore, science now demanded a space telescope with 6 to 8 meter aperture operating at L2. Mirror technology was identified as a critical capability necessary to enable the next generation of large aperture space telescopes. Specific telescope architectures were explored via three independent design concept studies conducted during the summer of 1996 (1). These studies identified two significant architectural constraints: segmentation and areal density. Because the launch vehicle fairing payload dynamic envelop diameter is approximately 4.5 meters, the only way to launch an 8 meter class mirror is to segment it, fold it and deploy it on orbit - resulting in actuation and control requirements. And, because of launch vehicle mass limits, the primary mirror allocation was only 1000 kg - resulting in a maximum areal density of 20 kg/m2. At the inception of

  17. The Configurable Aperture Space Telescope (CAST)

    Science.gov (United States)

    Ennico, Kimberly; Bendek, Eduardo A.; Lynch, Dana H.; Vassigh, Kenny K.; Young, Zion

    2016-07-01

    The Configurable Aperture Space Telescope, CAST, is a concept that provides access to a UV/visible-infrared wavelength sub-arcsecond imaging platform from space, something that will be in high demand after the retirement of the astronomy workhorse, the 2.4 meter diameter Hubble Space Telescope. CAST allows building large aperture telescopes based on small, compatible and low-cost segments mounted on autonomous cube-sized satellites. The concept merges existing technology (segmented telescope architecture) with emerging technology (smartly interconnected modular spacecraft, active optics, deployable structures). Requiring identical mirror segments, CAST's optical design is a spherical primary and secondary mirror telescope with modular multi-mirror correctors placed at the system focal plane. The design enables wide fields of view, up to as much as three degrees, while maintaining aperture growth and image performance requirements. We present a point design for the CAST concept based on a 0.6 meter diameter (3 x 3 segments) growing to a 2.6 meter diameter (13 x 13 segments) primary, with a fixed Rp=13,000 and Rs=8,750 mm curvature, f/22.4 and f/5.6, respectively. Its diffraction limited design uses a two arcminute field of view corrector with a 7.4 arcsec/mm platescale, and can support a range of platescales as fine as 0.01 arcsec/mm. Our paper summarizes CAST, presents a strawman optical design and requirements for the underlying modular spacecraft, highlights design flexibilities, and illustrates applications enabled by this new method in building space observatories.

  18. Building the James Webb Space Telescope

    Science.gov (United States)

    Gardner, Jonathan P.

    2012-01-01

    The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes. It will be a large (6.6m) cold (50K) telescope launched into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. JWST will make progress In almost every area of astronomy, from the first galaxies to form in the early universe to exoplanets and Solar System objects. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Near-Infrared Imager and Slitless Spectrograph will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. The observatory Is confirmed for launch in 2018; the design is complete and it is in its construction phase. Innovations that make JWST possible include large-area low-noise infrared detectors, cryogenic ASICs, a MEMS micro-shutter array providing multi-object spectroscopy, a non-redundant mask for interferometric coronagraphy and diffraction-limited segmented beryllium mirrors with active wavefront sensing and control. Recent progress includes the completion of the mirrors, the delivery of the first flight instruments and the start of the integration and test phase.

  19. Weighing 'El Gordo' with a precision scale: Hubble space telescope weak-lensing analysis of the merging galaxy cluster ACT-CL J0102–4915 at z = 0.87

    Energy Technology Data Exchange (ETDEWEB)

    Jee, M. James; Ng, Karen Y. [Department of Physics, University of California, Davis, One Shields Avenue, Davis, CA 95616 (United States); Hughes, John P.; Menanteau, Felipe [Department of Physics and Astronomy, Rutgers University, 136 Frelinghysen Rd., Piscataway, NJ 08854 (United States); Sifón, Cristóbal [Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA Leiden (Netherlands); Mandelbaum, Rachel [Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213 (United States); Barrientos, L. Felipe; Infante, Leopoldo [Departamento de Astronomía y Astrofísica, Facultad de Física, Ponticia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile)

    2014-04-10

    We present a Hubble Space Telescope weak-lensing study of the merging galaxy cluster 'El Gordo' (ACT-CL J0102–4915) at z = 0.87 discovered by the Atacama Cosmology Telescope (ACT) collaboration as the strongest Sunyaev-Zel'dovich decrement in its ∼1000 deg{sup 2} survey. Our weak-lensing analysis confirms that ACT-CL J0102–4915 is indeed an extreme system consisting of two massive (≳ 10{sup 15} M {sub ☉} each) subclusters with a projected separation of ∼0.7 h{sub 70}{sup −1} Mpc. This binary mass structure revealed by our lensing study is consistent with the cluster galaxy distribution and the dynamical study carried out with 89 spectroscopic members. We estimate the mass of ACT-CL J0102–4915 by simultaneously fitting two axisymmetric Navarro-Frenk-White (NFW) profiles allowing their centers to vary. We use only a single parameter for the NFW mass profile by enforcing the mass-concentration relation from numerical simulations. Our Markov-Chain-Monte-Carlo analysis shows that the masses of the northwestern (NW) and the southeastern (SE) components are M{sub 200c}=(1.38±0.22)×10{sup 15} h{sub 70}{sup −1} M{sub ⊙} and (0.78±0.20)×10{sup 15} h{sub 70}{sup −1} M{sub ⊙}, respectively, where the quoted errors include only 1σ statistical uncertainties determined by the finite number of source galaxies. These mass estimates are subject to additional uncertainties (20%-30%) due to the possible presence of triaxiality, correlated/uncorrelated large scale structure, and departure of the cluster profile from the NFW model. The lensing-based velocity dispersions are 1133{sub −61}{sup +58} km s{sup −1} and 1064{sub −66}{sup +62} km s{sup −1} for the NW and SE components, respectively, which are consistent with their spectroscopic measurements (1290 ± 134 km s{sup –1} and 1089 ± 200 km s{sup –1}, respectively). The centroids of both components are tightly constrained (∼4'') and close to the optical luminosity

  20. Hubble 15 years of discovery

    CERN Document Server

    Lindberg Christensen, Lars; Kornmesser, M

    2006-01-01

    Hubble: 15 Years of Discovery was a key element of the European Space Agency's 15th anniversary celebration activities for the 1990 launch of the NASA/ESA Hubble Space Telescope. As an observatory in space, Hubble is one of the most successful scientific projects of all time, both in terms of scientific output and its immediate public appeal.

  1. Shuttle to Space Station. Heart Assist Implant. Hubble Update. X-30 Mock-Up

    Science.gov (United States)

    1992-01-01

    Shuttle to Space Station, Heart Assist Implant, Hubble Update, and X-30 Mockup are the four parts that are discussed in this video. The first part, Shuttle to Space Station, is focussed on the construction and function of the Space Station Freedom. While part two, Heart Assist Implant, discusses a newly developed electromechanical device that helps to reduce heart attack by using electric shocks. Interviews with the co-inventor and patients are also included. Brief introduction to Hubble Telescope, problem behind its poor image quality (mirror aberration), and the plan to correct this problem are the three issues that are discussed in part three, Hubble Update. The last part, part four, reviews the X-30 Mockup designed by the staff and students of Mississippi State University.

  2. Scientific management of Space Telescope

    Science.gov (United States)

    Odell, C. R.

    1981-01-01

    A historical summay is given on the science management of the Space Telescope, the inception of which began in 1962, when scientists and engineers first recommended the development of a nearly diffraction limited substantial-size optical telescope. Phase A, the feasibility requirements generation phase, began in 1971 and consisted largely of NASA scientists and a NASA design. Phase B, the preliminary design phase, established a tiered structure of scientists, led by the Large Space Telescope operations and Management Work Group. A Mission Operations Working Group headed six instrument definition teams to develop the essential instrument definitions. Many changes took place during Phase B, before design and development, which began in 1978 and still continues today.

  3. Giving Birth to the James Webb Space Telescope: Part 1

    Science.gov (United States)

    Mather, John

    2013-01-01

    In late October 1995, I found a remarkable message on my answering machine from Ed Weiler, then the Program Scientist for the Hubble Space Telescope. Would I work on the next generation space telescope, the successor to the beautiful HST? It took me mere moments to work out the answer: Of course! At the time, my work on the COsmic Background Explorer (COBE) was finished, I was writing a book about it (The Very First Light, with John Boslough), and I thought NASA might never do anything nearly as spectacular again. Wow, was I happy to be surprised by that call!

  4. Hubble and Keck Telescope Observations of Active Asteroid 288P/300163 (2006 VW139)

    CERN Document Server

    Agarwal, Jessica; Weaver, Harold; Mutchler, Max; Larson, Stephen

    2015-01-01

    We present Hubble Space Telescope and Keck 10 meter telescope observations of active asteroid 288P/300163 (2006 VW139) taken to examine ejected dust. The nucleus is a C-type object with absolute magnitude $H_V$ = 17.0$\\pm$0.1 and estimated diameter $\\sim$2.6 km (for assumed visual geometric albedo $p_V$ = 0.04). Variations in the brightness of the nucleus at the 10% to 15% level are significant in both 2011 December and 2012 October but we possess too few data to distinguish variations caused by activity from those caused by rotation. The dust scattering cross-section in 2011 December is $\\sim$40 km$^2$, corresponding to a dust mass $\\sim$9$\\times$10$^6$ kg (88 $\\mu$m mean particle radius assumed). The full width at half maximum of the debris sheet varies from $\\sim$100 km near the nucleus to $\\sim$1000 km 30arcsec (40,000 km) east of it. Dust dynamical models indicate ejection speeds between 0.06 and 0.3 m s$^{-1}$, particle sizes between 10 and 300 $\\mu$m and an inverse square-root relation between particle...

  5. DESTINY, the Dark Energy Space Telescope

    Science.gov (United States)

    Lauer, T. R.; Morse, J. A.; Destiny Science Team

    2003-12-01

    We describe a mission concept for a 1.8-meter near-infrared (NIR) grism-mode space telescope optimized to return richly sampled Hubble diagrams of Type Ia and Type II supernovae (SNe) over the redshift range 0.5 the Universe as a function of time, and characterizing the nature of dark energy. The central concept for our proposed Dark Energy Space Telescope (DESTINY) is an all-grism NIR survey camera. SNe will be discovered by repeated imaging of an area located at the north ecliptic pole. Grism spectra with resolving power l/Dl = R * 100 will provide broad-band spectrophotometry, redshifts, SNe classification, as well as valuable time-resolved diagnostic data for understanding the SN explosion physics. Our approach features only a single mode of operation, a single detector technology, and a single instrument. Although grism spectroscopy is slow compared to SN detection in any single broad-band filter for photometry, or to conventional slit spectra for spectral diagnostics, the multiplex advantage of observing a large field-of-view over a full octave in wavelength simultaneously makes this approach highly competitive.

  6. Jupiter's Upper Atmospheric Winds Revealed in Ultraviolet Images by Hubble Telescope

    Science.gov (United States)

    1994-01-01

    These four NASA Hubble Space Telescope images of Jupiter, as seen in visible (violet) and far-ultraviolet (UV) wavelengths, show the remarkable spreading of the clouds of smoke and dust thrown into the atmosphere after the impacts of the fragments of comet P/Shoemaker-Levy 9. These dark regions provide the only information ever obtained on the wind direction and speed in Jupiter's upper atmosphere.TOP Three impact sites appear as dark smudges lined up along Jupiter's southern hemisphere (from left to right, sites C, A, and E). This pair of images was obtained on 17 July, several hours after the E impact. These 3 impact sites appear strikingly darker in the far-ultraviolet images to the right. This is because the smoke and dust rising from the fireballs absorbs UV light more strongly than violet light, so that the clouds appear both darker and larger in the UV images. Apparently, the fireball and plume threw large amounts of material completely above the atmosphere. This material diffused back down through the atmosphere with the smaller and lighter particles suspended at high altitudes.BOTTOM Hubble's view of the same hemisphere of Jupiter 12-13 days later shows that the smoke and dust have now been spread mainly in the east/west direction by the prevailing winds at the altitude where the dark material is suspended or 'floating' in the atmosphere.HST shows that winds in Jupiter's upper atmosphere carry the high altitude smoke and dust in different directions than in the lower atmosphere. For example, the UV image shows a fainter cloud near 45 deg. south latitude, which does not appear in the violet image. The fainter cloud may be due to high altitude material which is drifting with the upper atmospheric winds to the north away from the polar regions. However, in the left-hand impact regions the clouds being observed are lower in the atmosphere where there is apparently no such northerly wind.The violet images show the Great Red Spot, on the eastern (right) limb

  7. Academic Training: Deep Space Telescopes

    CERN Multimedia

    Françoise Benz

    2006-01-01

    2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 20, 21, 22, 23, 24 February from 11:00 to 12:00 - Council Chamber on 20, 21, 23, 24 February, TH Auditorium, bldg 4 - 3-006, on 22 February Deep Space Telescopes G. BIGNAMI / CNRS, Toulouse, F & Univ. di Pavia, I The short series of seminars will address results and aims of current and future space astrophysics as the cultural framework for the development of deep space telescopes. It will then present such new tools, as they are currently available to, or imagined by, the scientific community, in the context of the science plans of ESA and of all major world space agencies. Ground-based astronomy, in the 400 years since Galileo's telescope, has given us a profound phenomenological comprehension of our Universe, but has traditionally been limited to the narrow band(s) to which our terrestrial atmosphere is transparent. Celestial objects, however, do not care about our limitations, and distribute most of the information about their physics thro...

  8. Detectors for the space telescope

    Science.gov (United States)

    Kelsall, T.

    1978-01-01

    This review of Space Telescope (ST) detectors is divided into two parts. The first part gives short summaries of detector programs carried out during the final planning stage (Phase B) of the ST and discusses such detectors as Photicon, the MAMA detectors, the CODACON, the University of Maryland ICCD, the Goddard Space Flight Center ICCD, and the 70 mm SEC TV sensor. The second part describes the detectors selected for the first ST flight, including the wide field/planetary camera, the faint object and high resolution spectrographs, and the high speed photometer.

  9. HUBBLE AND KECK TELESCOPE OBSERVATIONS OF ACTIVE ASTEROID 288P/300163 (2006 VW139)

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Jessica [Max Planck Institute for Solar System Research, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany); Jewitt, David [Department Earth, Planetary and Space Sciences, UCLA, 595 Charles Young Drive East, Box 951567 Los Angeles, CA 90095-1567 (United States); Weaver, Harold [The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); Mutchler, Max [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Larson, Stephen, E-mail: agarwal@mps.mpg.de [Lunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd. Tucson AZ 85721-0092 (United States)

    2016-01-15

    We present Hubble Space Telescope (HST) and Keck 10 m telescope observations of active asteroid 288P/300163 (2006 VW139) taken to examine ejected dust. The nucleus is a C-type object with absolute magnitude H{sub V} = 17.0 ± 0.1 and estimated diameter ∼2.6 km (for assumed visual geometric albedo p{sub V} = 0.04). Variations in the brightness of the nucleus at the 10%–15% level are significant in both 2011 December and 2012 October but we possess too few data to distinguish variations caused by activity from those caused by rotation. The dust scattering cross-section in 2011 December is ∼40 km{sup 2}, corresponding to a dust mass ∼9 × 10{sup 6} kg (88 μm mean particle radius assumed). The FWHM of the debris sheet varies from ∼100 km near the nucleus to ∼1000 km 30″ (40,000 km) east of it. Dust dynamical models indicate ejection speeds between 0.06 and 0.3 m s{sup −1}, particle sizes between 10 and 300 μm and an inverse square-root relation between particle size and velocity. Overall, the data are most simply explained by prolonged, low velocity ejection of dust, starting in or before 2011 July and continuing until at least 2011 October. These properties are consistent with the sublimation of near-surface ice aided by centrifugal forces. The high spatial resolution of our HST images (52 km pixel{sup −1}) reveals details that remained hidden in previous ground-based observations, such as the extraordinarily small vertical extent of the dust sheet, ejection speeds well below the nucleus escape speed, and the possibility of a binary nucleus.

  10. High-Flying Telescope

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    Scientists at the Space Telescope Science Institute,which operates the Hubble Space Telescope,have proposed a new telescope that would have twice the resolution of Hubble at about one-tenth the cost. It would hover seven miles above Earth,dangling below a football-field-size helium balloon

  11. The age of the universe, the Hubble constant, the accelerated expansion and the Hubble effect

    OpenAIRE

    Soares,Domingos

    2009-01-01

    The idea of an accelerating universe comes almost simultaneously with the determination of Hubble's constant by one of the Hubble Space Telescope Key Projects. The age of the universe dilemma is probably the link between these two issues. In an appendix, I claim that "Hubble's law" might yet to be investigated for its ultimate cause, and suggest the "Hubble effect" as the searched candidate.

  12. The age of the universe, the Hubble constant, the accelerated expansion and the Hubble effect

    OpenAIRE

    Soares, Domingos

    2009-01-01

    The idea of an accelerating universe comes almost simultaneously with the determination of Hubble's constant by one of the Hubble Space Telescope Key Projects. The age of the universe dilemma is probably the link between these two issues. In an appendix, I claim that "Hubble's law" might yet to be investigated for its ultimate cause, and suggest the "Hubble effect" as the searched candidate.

  13. Novel In-Space Manufacturing Concepts for the Development of Large Space Telescopes

    Science.gov (United States)

    Mooney, James T.; Reardon, Patrick; Gregory Don; Manning, Andrew; Blackmon, Jim; Howsman, Tom; Williams, Philip; Brantley, Whitt; Rakoczy, John; Herren, Kenneth

    2006-01-01

    There is a continuous demand for larger, lighter, and higher quality telescopes. Over the past several decades, we have seen the evolution from launchable 2 meter-class telescopes (such as Hubble), to today s demand for deployable 6 meter-class telescopes (such as JWST), to tomorrow s need for up to 150 meter-class telescopes. As the apertures continue to grow, it will become much more difficult and expensive to launch assembled telescope structures. To address this issue, we are seeing the emergence of new novel structural concepts, such as inflatable structures and membrane optics. While these structural concepts do show promise, it is very difficult to achieve and maintain high surface figure quality. Another potential solution to develop large space telescopes is to move the fabrication facility into space and launch the raw materials. In this paper we present initial in-space manufacturing concepts to enable the development of large telescopes. This includes novel approaches for the fabrication of both the optical elements and the telescope support structure. We will also discuss potential optical designs for large space telescopes and describe their relation to the fabrication methods. These concepts are being developed to meet the demanding requirements of DARPA s LASSO (Large Aperture Space Surveillance Optic) program which currently requires a 150 meter optical aperture with a 17 degree field of view.

  14. Hubble Deep Fields

    Science.gov (United States)

    Ferguson, H.; Murdin, P.

    2000-11-01

    The Hubble Deep Fields are two small areas of the sky that were carefully selected for deep observations by the HUBBLE SPACE TELESCOPE (HST). They represent the deepest optical observations to date and reveal galaxies as faint as V=30, 4 billion times fainter than can be seen with the unaided eye....

  15. Far Ultraviolot Space Telescope (FAUST)

    Science.gov (United States)

    Bowyer, S.

    1988-01-01

    The Far Ultraviolet Space Telescope is a compact, wide field-of-view, far ultraviolet instrument designed for observations of extended and point sources of astronomical interest. It was originally used in sounding rocket work by both French and American investigators. The instrument was modified for flight on the space shuttle and flew on the Spacelab 1 mission as a joint effort between the Laboratoire d'Astronomie Spatiale and the University of California, Berkeley. The prime experiment objective of this telescope on the Atmospheric Laboratory Applications and Science (ATLAS 1) NASA mission is to observe faint astronomical sources in the far ultraviolet with sensitivities far higher than previously available. The experiment will cover the 1300 to 1800 A band, which is inaccessible to observers on earth. The observing program during the mission consists of obtaining deep sky images during spacecraft nighttime. The targets will include hot stars and nebulae in our own galaxy, faint diffuse galactic features similar to the cirrus clouds seen by the Infrared Astronomical Satellite (IRAS), large nearby galaxies, nearby clusters of galaxies, and objects of cosmological interest such as quasars and the diffuse far ultraviolet background.

  16. Origins Space Telescope: Study Plan

    Science.gov (United States)

    Cooray, Asantha R.; Origins Space Telescope Study Team

    2017-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its spectrographs will enable 3D surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu. This presentation will provide a summary of the OST STDT, the OST Study Team based at NASA Goddard Space Flight Center, study partners, and the advisory panel to the study. This presentation will also summarize recent activities, including the process used to reach a decision on the mission architecture, the identification of key science drivers, and the key study milestones between 2017 and 2020.

  17. Space Telescope Fine Guidance Sensor Bearing Anomaly

    Science.gov (United States)

    Loewenthal, S.; Esper, J.; Pan, J.; Decker, J.

    1996-01-01

    Early in 1993, a servo motor within one of three Fine Guidance Sensors (FGS) aboard the Hubble Space Telescope (HST) reached stall torque levels on several occasions. Little time was left to plan replacement during the first servicing mission, scheduled at the end of '93. Accelerated bearing life tests confirmed that a small angle rocking motion, known as Coarse Track (CT), accelerated bearing degradation. Saturation torque levels were reached after approximately 20 million test cycles, similar to the flight bearings. Reduction in CT operation, implemented in flight software, extended FGS life well beyond the first servicing mission. However in recent years, bearing torques have resumed upward trends and together with a second, recent bearing torque anomaly has necessitated a scheduled FGS replacement during the upcoming second servicing mission in '97. The results from two series of life tests to quantify FGS bearing remaining life, discussion of bearing on-orbit performance, and future plans to service the FGS servos are presented in this paper.

  18. Space Telescope precision pointing control system

    Science.gov (United States)

    Beals, G. A.; Crum, R. C.; Dougherty, H. J.; Hegel, D. K.; Kelley, J. L.

    1986-01-01

    The Hubble Space Telescope has the most stringent pointing requirements imposed on any spacecraft to date. The overall HST stability shall not exceed 0.007 arc-seconds rms. The Pointing Control System utilizes fine guidance sensors and rate gyros for attitude reference and rate information. Control torques are provided by reaction wheels. A digital computer collects the sensor data, performs the control law computations, and sends torque commands to the reaction wheels. To attain this precision pointing, improvements were made to the rate gyros to lower their noise characteristics and to the reaction wheels to reduce their emitted vibration levels. The control system design was validated in a test sequence which progressed from model verification tests on an air-bearing to operations-oriented, closed loop testing on the assembled vehicle. A test system is described which allowed the simultaneous production of test case command loads for the flight computer and plots of predicted profiles to assist in test data analysis. Workarounds were required during system test to accommodate gyro biases and noise introduced into the closed loop system. Testing and analysis indicate that the HST will provide the capability to meet the requirements for precision pointing.

  19. DESTINY: The Dark Energy Space Telescope

    Science.gov (United States)

    Lauer, T. R.; Destiny Science Team

    2005-08-01

    The Dark Energy Space Telescope (DESTINY) is an all-grism NIR 1.8-m survey camera optimized to return richly sampled Hubble diagrams of Type Ia and Type II supernovae (SN) over the redshift range 0.5 the Universe as a function of time, and characterizing the nature of the so-called ``dark energy" component of the Universe. SN will be discovered by repeated imaging of a 7.5-sq.-deg. area located at the north ecliptic poles. Grism spectra with resolving power λ/Δλ = R˜75 will provide broad-band spectrophotometry, redshifts, SN classification, and valuable time-resolved diagnostic data for understanding the SN explosion physics. This methodology features only a single mode of operation with no time-critical interactions, a single detector technology, and a single instrument. Although grism spectroscopy is slow compared with SN detection in any single broad-band filter for photometry, or to conventional slit spectra for spectral diagnostics, the multiplex advantage of being able to observe a large field of view simultaneously over a full octave in wavelength makes this approach highly competitive.

  20. Origins Space Telescope: Community Participation

    Science.gov (United States)

    Carey, Sean J.; Origins Space Telescope Study Team

    2017-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its imagers and spectrographs will enable a variety of surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. This poster will outline the ways in which the astronomical community can participate in the STDT activities and a summary of tools that are currently available or are planned for the community during the study. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu.

  1. Twenty Meter Space Telescope Based on Diffractive Fresnel Lens

    Energy Technology Data Exchange (ETDEWEB)

    Early, J; Hyde, R; Baron, R

    2003-06-26

    Diffractive lenses offer two potential advantages for very large aperture space telescopes; very loose surface-figure tolerances and physical implementation as thin, flat optical elements. In order to actually realize these advantages one must be able to build large diffractive lenses with adequate optical precision and also to compactly stow the lens for launch and then fully deploy it in space. We will discuss the recent fabrication and assembly demonstration of a 5m glass diffractive Fresnel lens at LLNL. Optical performance data from smaller full telescopes with diffractive lens and corrective optics show diffraction limited performance with broad bandwidths. A systems design for a 20m space telescope will be presented. The primary optic can be rolled to fit inside of the standard fairings of the Delta IV vehicle. This configuration has a simple deployment and requires no orbital assembly. A twenty meter visible telescope could have a significant impact in conventional astronomy with eight times the resolution of Hubble and over sixty times the light gathering capacity. If the light scattering is made acceptable, this telescope could also be used in the search for terrestrial planets.

  2. The James Webb Space Telescope

    CERN Document Server

    Gardner, J P; Clampin, M; Doyon, R; Greenhouse, M A; Hammel, H B; Hutchings, J B; Jakobsen, P; Lilly, S J; Long, K S; Lunine, J I; McCaughrean, M J; Mountain, M; Nella, J; Rieke, G H; Rieke, M J; Rix, H W; Smith, E P; Sonneborn, G; Stiavelli, M; Stockman, H S; Windhorst, R A; Wright, G S; Gardner, Jonathan P.; Mather, John C.; Clampin, Mark; Doyon, Rene; Greenhouse, Matthew A.; Hammel, Heidi B.; Hutchings, John B.; Jakobsen, Peter; Lilly, Simon J.; Long, Knox S.; Lunine, Jonathan I.; Caughrean, Mark J. Mc; Mountain, Matt; Nella, John; Rieke, George H.; Rieke, Marcia J.; Rix, Hans-Walter; Smith, Eric P.; Sonneborn, George; Stiavelli, Massimo; Windhorst, Rogier A.; Wright, Gillian S.

    2006-01-01

    The James Webb Space Telescope (JWST) is a large (6.6m), cold (50K), infrared-optimized space observatory that will be launched early in the next decade. The observatory will have four instruments: a near-infrared camera, a near-infrared multi-object spectrograph, and a tunable filter imager will cover the wavelength range, 0.6 to 5.0 microns, while the mid-infrared instrument will do both imaging and spectroscopy from 5.0 to 29 microns. The JWST science goals are divided into four themes. The End of the Dark Ages: First Light and Reionization theme seeks to identify the first luminous sources to form and to determine the ionization history of the early universe. The Assembly of Galaxies theme seeks to determine how galaxies and the dark matter, gas, stars, metals, morphological structures, and active nuclei within them evolved from the epoch of reionization to the present day. The Birth of Stars and Protoplanetary Systems theme seeks to unravel the birth and early evolution of stars, from infall on to dust-e...

  3. Titan Science with the James Webb Space Telescope (JWST)

    CERN Document Server

    Nixon, Conor A; Adamkovics, Mate; Bezard, Bruno; Bjoraker, Gordon L; Cornet, Thomas; Hayes, Alexander G; Lellouch, Emmanuel; Lemmon, Mark T; Lopez-Puertas, Manuel; Rodriguez, Sebastien; Sotin, Christophe; Teanby, Nicholas A; Turtle, Elizabeth P; West, Robert A

    2015-01-01

    The James Webb Space Telescope (JWST), scheduled for launch in 2018, is the successor to the Hubble Space Telescope (HST) but with a significantly larger aperture (6.5 m) and advanced instrumentation focusing on infrared science (0.6-28.0 $\\mu$m ). In this paper we examine the potential for scientific investigation of Titan using JWST, primarily with three of the four instruments: NIRSpec, NIRCam and MIRI, noting that science with NIRISS will be complementary. Five core scientific themes are identified: (i) surface (ii) tropospheric clouds (iii) tropospheric gases (iv) stratospheric composition and (v) stratospheric hazes. We discuss each theme in depth, including the scientific purpose, capabilities and limitations of the instrument suite, and suggested observing schemes. We pay particular attention to saturation, which is a problem for all three instruments, but may be alleviated for NIRCam through use of selecting small sub-arrays of the detectors - sufficient to encompass Titan, but with significantly fas...

  4. Hubble Camera Resumes Science Operation With Picture Of 'Butterfly' In Space.

    Science.gov (United States)

    2002-01-01

    he Hubble Space Telescope's Wide Field and Planetary Camera 2 (WFPC2) is back at work, capturing this black-and-white image of the 'butterfly wing'-shaped nebula, NGC 2346. The nebula is about 2,000 light-years away from Earth in the direction of the constellation Monoceros. It represents the spectacular 'last gasp' of a binary star system at the nebula's center. The image was taken on March 6, as part of the recommissioning of the Hubble Space Telescope's previously installed scientific instruments following the successful servicing of the HST by NASA astronauts in February. WFPC2 was installed in HST during the servicing mission in 1993. At the center of the nebula lies a pair of stars that are so close together that they orbit around each other every 16 days. This is so close that, even with Hubble, the pair of stars cannot be resolved into its two components. One component of this binary is the hot core of a star that has ejected most of its outer layers, producing the surrounding nebula. Astronomers believe that this star, when it evolved and expanded to become a red giant, actually swallowed its companion star in an act of stellar cannibalism. The resulting interaction led to a spiraling together of the two stars, culminating in ejection of the outer layers of the red giant. Most of the outer layers were ejected into a dense disk, which can still be seen in the Hubble image, surrounding the central star. Later the hot star developed a fast stellar wind. This wind, blowing out into the surrounding disk, has inflated the large, wispy hourglass-shaped wings perpendicular to the disk. These wings produce the butterfly appearance when seen in projection. The total diameter of the nebula is about one-third of a light-year, or 2 trillion miles. Our own Sun will eject a nebula about 5 billion years from now. However, the Sun is not a double star, so its nebula may well be more spherical in shape. The image was taken through a filter that shows the light of glowing

  5. Hubble Camera Resumes Science Operation With Picture Of 'Butterfly' In Space.

    Science.gov (United States)

    2002-01-01

    he Hubble Space Telescope's Wide Field and Planetary Camera 2 (WFPC2) is back at work, capturing this black-and-white image of the 'butterfly wing'-shaped nebula, NGC 2346. The nebula is about 2,000 light-years away from Earth in the direction of the constellation Monoceros. It represents the spectacular 'last gasp' of a binary star system at the nebula's center. The image was taken on March 6, as part of the recommissioning of the Hubble Space Telescope's previously installed scientific instruments following the successful servicing of the HST by NASA astronauts in February. WFPC2 was installed in HST during the servicing mission in 1993. At the center of the nebula lies a pair of stars that are so close together that they orbit around each other every 16 days. This is so close that, even with Hubble, the pair of stars cannot be resolved into its two components. One component of this binary is the hot core of a star that has ejected most of its outer layers, producing the surrounding nebula. Astronomers believe that this star, when it evolved and expanded to become a red giant, actually swallowed its companion star in an act of stellar cannibalism. The resulting interaction led to a spiraling together of the two stars, culminating in ejection of the outer layers of the red giant. Most of the outer layers were ejected into a dense disk, which can still be seen in the Hubble image, surrounding the central star. Later the hot star developed a fast stellar wind. This wind, blowing out into the surrounding disk, has inflated the large, wispy hourglass-shaped wings perpendicular to the disk. These wings produce the butterfly appearance when seen in projection. The total diameter of the nebula is about one-third of a light-year, or 2 trillion miles. Our own Sun will eject a nebula about 5 billion years from now. However, the Sun is not a double star, so its nebula may well be more spherical in shape. The image was taken through a filter that shows the light of glowing

  6. Micrometeoroid Impacts on the Hubble Sace Telescope Wide Field and Planetary Camera 2: Ion Beam Analysis of Subtle Impactor Traces

    Science.gov (United States)

    Grime, G. W.; Webb, R. P.; Jeynes, C.; Palitsin, V. V.; Colaux, J. L.; Kearsley, A. T.; Ross, D. K.; Anz-Meador, P.; Liou, J. C.; Opiela, J.; hide

    2014-01-01

    Recognition of origin for particles responsible for impact damage on spacecraft such as the Hubble Space Telescope (HST) relies upon postflight analysis of returned materials. A unique opportunity arose in 2009 with collection of the Wide Field and Planetary Camera 2 (WFPC2) from HST by shuttle mission STS-125. A preliminary optical survey confirmed that there were hundreds of impact features on the radiator surface. Following extensive discussion between NASA, ESA, NHM and IBC, a collaborative research program was initiated, employing scanning electron microscopy (SEM) and ion beam analysis (IBA) to determine the nature of the impacting grains. Even though some WFPC2 impact features are large, and easily seen without the use of a microscope, impactor remnants may be hard to find.

  7. Spitzer Space Telescope proposal process

    Science.gov (United States)

    Laine, S.; Silbermann, N. A.; Rebull, L. M.; Storrie-Lombardi, L. J.

    2006-06-01

    This paper discusses the Spitzer Space Telescope General Observer proposal process. Proposals, consisting of the scientific justification, basic contact information for the observer, and observation requests, are submitted electronically using a client-server Java package called Spot. The Spitzer Science Center (SSC) uses a one-phase proposal submission process, meaning that fully-planned observations are submitted for most proposals at the time of submission, not months after acceptance. Ample documentation and tools are available to the observers on SSC web pages to support the preparation of proposals, including an email-based Helpdesk. Upon submission proposals are immediately ingested into a database which can be queried at the SSC for program information, statistics, etc. at any time. Large proposals are checked for technical feasibility and all proposals are checked against duplicates of already approved observations. Output from these tasks is made available to the Time Allocation Committee (TAC) members. At the review meeting, web-based software is used to record reviewer comments and keep track of the voted scores. After the meeting, another Java-based web tool, Griffin, is used to track the approved programs as they go through technical reviews, duplication checks and minor modifications before the observations are released for scheduling. In addition to detailing the proposal process, lessons learned from the first two General Observer proposal calls are discussed.

  8. Observations of the Hubble Deep Field with the Infrared Space Observatory .4. Association of sources with Hubble Deep Field galaxies

    DEFF Research Database (Denmark)

    Mann, R.G.; Oliver, S.J.; Serjeant, S.B.G.

    1997-01-01

    We discuss the identification of sources detected by the Infrared Space Observatory (ISO) at 6.7 and 15 mu m in the Hubble Deep Field (HDF) region. We conservatively associate ISO sources with objects in existing optical and near-infrared HDF catalogues using the likelihood ratio method, confirming...... these results (and, in one case, clarifying them) with independent visual searches, We find 15 ISO sources to be reliably associated with bright [I-814(AB) Hubble Flanking Fields (10 galaxies...

  9. Observations of the Hubble Deep Field with the Infrared Space Observatory .4. Association of sources with Hubble Deep Field galaxies

    DEFF Research Database (Denmark)

    Mann, R.G.; Oliver, S.J.; Serjeant, S.B.G.;

    1997-01-01

    We discuss the identification of sources detected by the Infrared Space Observatory (ISO) at 6.7 and 15 mu m in the Hubble Deep Field (HDF) region. We conservatively associate ISO sources with objects in existing optical and near-infrared HDF catalogues using the likelihood ratio method, confirming...... these results (and, in one case, clarifying them) with independent visual searches, We find 15 ISO sources to be reliably associated with bright [I-814(AB) Hubble Flanking Fields (10 galaxies...

  10. Introduction to the Solar Space Telescope

    Indian Academy of Sciences (India)

    G. Ai; S. Jin; S. Wang; B. Ye; S. Yang

    2000-09-01

    The design of the space solar telescope (SST) (phase B) has been completed. The manufacturing is under development. At the end of 2000, it will be assembled. The basic aspect will be introduced in this paper.

  11. Solar System Science with the James Webb Space Telescope

    Science.gov (United States)

    Hammel, Heidi B.; Norwood, J.; Chanover, N.; Hines, D. C.; Stansberry, J.; Lunine, J. I.; Tiscareno, M. S.; Milam, S. N.; Sonneborn, G.; Brown, M.

    2013-10-01

    The James Webb Space Telescope (JWST) will succeed the Hubble Space Telescope as NASA’s premier space-based platform for observational astronomy. This 6.5-meter telescope, which is optimized for observations in the near and mid infrared, will be equipped with four state-of-the-art imaging, spectroscopic, and coronagraphic instruments. These instruments, along with the telescope’s moving target capabilities, will enable the infrared study of solar system objects with unprecedented detail (see companion presentation by Sonneborn et al.). This poster features highlights for planetary science applications, extracted from a white paper in preparation. We present a number of hypothetical solar system observations as a means of demonstrating potential planetary science observing scenarios; the list of applications discussed here is far from comprehensive. The goal of this poster and the subsequent white paper is to stimulate discussion and encourage participation in JWST planning among members of the planetary science community, and to encourage feedback to the JWST Project on any desired observing capabilities, data products, and analysis procedures that would enhance the use of JWST for solar system studies. The upcoming white paper updates and supersedes the solar system white paper published by the JWST Project in 2010 (Lunine et al., 2010), and is based in part on JWST events held at the 2012 DPS, the 2013 LPSC meeting, and this DPS (JWST Town Hall, Thursday, 10 October 2013, 12-1 pm).

  12. The space telescope: A study of NASA, science, technology, and politics

    Science.gov (United States)

    Smith, Robert William

    1989-01-01

    Scientific, technological, economic, and political aspects of NASA efforts to orbit a large astronomical telescope are examined in a critical historical review based on extensive interviews with participants and analysis of published and unpublished sources. The scientific advantages of large space telescopes are explained; early plans for space observatories are summarized; the history of NASA and its major programs is surveyed; the redesign of the original Large Space Telescope for Shuttle deployability is discussed; the impact of the yearly funding negotiations with Congress on the development of the final Hubble Space Telescope (HST) is described; and the implications of the HST story for the future of large space science projects are explored. Drawings, photographs, a description of the HST instruments and systems, and lists of the major contractors and institutions participating in the HST program are provided.

  13. Weighing "El Gordo" with a Pecision Scale: Hubble Space Telescope Weak-lensing Analysis of the Merging Galaxy Cluster ACT-CL J0102-4915 at z=0.87

    CERN Document Server

    Jee, M James; Menanteau, Felipe; Sifon, Cristobal; Mandelbaum, Rachel; Barrientos, L Felipe; Infante, Leopoldo; Ng, Karen Y

    2013-01-01

    (Abridged) We present a HST weak-lensing study of the merging galaxy cluster "El Gordo" (ACT-CL J0102-4915) at z=0.87 discovered by the Atacama Cosmology Telescope collaboration as the strongest SZ decrement in its ~1000 sq. deg survey. Our weak-lensing analysis confirms that ACT-CL J0102-4915 is indeed an extreme system consisting of two massive (~10^15 Msun each) subclusters with a projected separation of ~0.7 Mpc. This binary mass structure revealed by our lensing study is consistent with the cluster galaxy distribution and the dynamical study carried out with 89 spectroscopic members. We estimate the mass of ACT-CL J0102-4915 by simultaneously fitting two axisymmetric NFW profiles allowing their centers to vary. Our MCMC analysis shows that the masses of the northwestern (NW) and the southeastern (SE) components are M200c=(1.40+-0.31) x 10^15 Msun and (0.75+-0.17) x 10^15 Msun, respectively. The lensing-based velocity dispersions are consistent with their spectroscopic measurements. The centroids of both ...

  14. Advances in the archiving and distribution facilities at the Space Telescope Science Institute

    Science.gov (United States)

    Hanisch, Robert J.; Postman, Marc; Pollizzi, Joseph; Richon, J.

    1998-07-01

    The Hubble Data Archive at the Space Telescope Science Institute contains over 4.3 TB of data, primarily for the Hubble Space Telescope, but also from complementary space- based and ground-based facilities. We are in the process of upgrading and generalizing many of the HDA's component system, developing tools to provide more integrated access to the HDA holdings, and working with other major data providing organizations to implement global data location services for astronomy and other space science disciplines. This paper describes the key elements of our archiving and data distribution systems, including a planned transition to DVD media, data compression, data segregation, on-the-fly calibration, an engineering data warehouse, and distributed search and retrieval facilities.

  15. Removing the Fringes from Space Telescope Imaging Spectrograph Slitless Spectra

    Science.gov (United States)

    Malumuth, Eliot M.; Hill, Robert S.; Gull, Ted; Woodgate, Bruce E.; Bowers, Charles W.; Kimble, Randy A.; Lindler, Don; Plait, Phil; Blouke, Morley

    2003-02-01

    Using what is known about the physical and chemical structure of the CCD detector on the Space Telescope Imaging Spectrograph (STIS) and over 50 calibration images taken with different wavelength mappings onto the detector, we have devised a model function that allows us to predict the fringing of any spectral image taken with the STIS CCD. This function is especially useful for spectra taken without a slit with the G750L grating. The STIS parallel observing program uses this ``slitless spectroscopy'' mode extensively. The arbitrary mapping of wavelength versus position that results from each source's chance position in the field renders direct calibration of the fringe amplitudes in this mode impossible. However, we find that correcting observed data using our semiempirical fringing model produces a substantial reduction in the fringe amplitudes. Tests using the flux calibration white dwarf standard G191-B2B show that we can reduce the fringe amplitude in the 9000-10000 Å region from about 20% peak to peak (10% rms) to about 4% peak to peak (2% rms) using the model, while a standard calibration using a ``fringe flat'' reduces the fringe amplitudes to 3.3% peak to peak (1.7% rms). The same technique is applicable to other astronomical CCDs. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. Funding of this activity was through the Space Telescope Imaging Spectrograph Guaranteed Time Observations.

  16. Investigations into Generalization of Constraint-Based Scheduling Theories with Applications to Space Telescope Observation Scheduling

    Science.gov (United States)

    Muscettola, Nicola; Smith, Steven S.

    1996-01-01

    This final report summarizes research performed under NASA contract NCC 2-531 toward generalization of constraint-based scheduling theories and techniques for application to space telescope observation scheduling problems. Our work into theories and techniques for solution of this class of problems has led to the development of the Heuristic Scheduling Testbed System (HSTS), a software system for integrated planning and scheduling. Within HSTS, planning and scheduling are treated as two complementary aspects of the more general process of constructing a feasible set of behaviors of a target system. We have validated the HSTS approach by applying it to the generation of observation schedules for the Hubble Space Telescope. This report summarizes the HSTS framework and its application to the Hubble Space Telescope domain. First, the HSTS software architecture is described, indicating (1) how the structure and dynamics of a system is modeled in HSTS, (2) how schedules are represented at multiple levels of abstraction, and (3) the problem solving machinery that is provided. Next, the specific scheduler developed within this software architecture for detailed management of Hubble Space Telescope operations is presented. Finally, experimental performance results are given that confirm the utility and practicality of the approach.

  17. Alignment of the James Webb Space Telescope optical telescope element

    Science.gov (United States)

    Glassman, Tiffany; Levi, Joshua; Liepmann, Till; Hahn, Walter; Bisson, Gary; Porpora, Dan; Hadjimichael, Theo

    2016-07-01

    The optical telescope element (OTE) of the James Webb Space Telescope has now been integrated and aligned. The OTE comprises the flight mirrors and the structure that supports them - 18 primary mirror segments, the secondary mirror, and the tertiary and fine steering mirrors (both housed in the aft optics subsystem). The primary mirror segments and the secondary mirror have actuators to actively control their positions during operations. This allows the requirements for aligning the OTE subsystems to be in the range of microns rather than nanometers. During OTE integration, the alignment of the major subsystems of the OTE structure and optics were controlled to ensure that, when the telescope is on orbit and at cryogenic temperatures, the active mirrors will be within the adjustment range of the actuators. Though the alignment of this flagship mission was complex and intricate, the key to a successful integration process turned out to be very basic: a clear, concise series of steps employing advanced planning, backup measurements, and cross checks that this multi-organizational team executed with a careful and methodical approach. This approach was not only critical to our own success but has implications for future space observatories.

  18. Development of space telescope non-ORU hardware

    Science.gov (United States)

    Robertson, K. B.; Henderson, D. E.

    1985-12-01

    Since 1979 work has progressed in the development of the Hubble Space Telescope (HST) mockup. Underwater simulations to evaluate proposed on-orbit servicing tasks have also been done. These tasks involve the planned changeout of scientific instruments and the unscheduled changeout of other orbital replacement units (ORUs) such as batteries and computers. The HST components and subsystems that originally were designated ORUs were the items that were mission critical and were designed for easy changeout. Mockups of 14 non-ORU items were designed and fabricated for the purpose of evaluating the EVA changetasks in the MSFC Neutral Buoyancy Simulator (NBS). The objectives of this design/fabrication/test activity were to design and fabricate the potential ORUs so they contained realistic interfaces and were compatible with the NBS environments. The attachment of the mockup hardware to the spacecraft mockup was similar to the flight version. Also, the hardware connectors were flight-like.

  19. Origins Space Telescope: Telescope Design and Instrument Specifications

    Science.gov (United States)

    Meixner, Margaret; Carter, Ruth; Leisawitz, David; Dipirro, Mike; Flores, Anel; Staguhn, Johannes; Kellog, James; Roellig, Thomas L.; Melnick, Gary J.; Bradford, Charles; Wright, Edward L.; Zmuidzinas, Jonas; Origins Space Telescope Study Team

    2017-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, one of the four science and technology definition studies of NASA Headquarters for the 2020 Astronomy and Astrophysics Decadal survey. The renaming of the mission reflects Origins science goals that will discover and characterize the most distant galaxies, nearby galaxies and the Milky Way, exoplanets, and the outer reaches of our Solar system. This poster will show the preliminary telescope design that will be a large aperture (>8 m in diameter), cryogenically cooled telescope. We will also present the specifications for the spectrographs and imagers over a potential wavelength range of ~10 microns to 1 millimeter. We look forward to community input into this mission definition over the coming year as we work on the concept design for the mission. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. We welcome you to contact the Science and Technology Definition Team (STDT) with your science needs and ideas by emailing us at firsurveyor_info@lists.ipac.caltech.edu.

  20. The role of space telescopes in the characterization of transiting exoplanets.

    Science.gov (United States)

    Hatzes, Artie P

    2014-09-18

    Characterization studies now have a dominant role in the field of exoplanets. Such studies include the measurement of an exoplanet's bulk density, its brightness temperature and the chemical composition of its atmosphere. The use of space telescopes has played a key part in the characterization of transiting exoplanets. These facilities offer astronomers data of exquisite precision and temporal sampling as well as access to wavelength regions of the electromagnetic spectrum that are inaccessible from the ground. Space missions such as the Hubble Space Telescope, Microvariability and Oscillations of Stars (MOST), Spitzer Space Telescope, Convection, Rotation and Planetary Transits (CoRoT), and Kepler have rapidly advanced our knowledge of the physical properties of exoplanets and have blazed a trail for a series of future space missions that will help us to understand the observed diversity of exoplanets.

  1. Hubble Space Telescope NICMOS Polarization Measurements of OMC-1

    CERN Document Server

    Simpson, J P; Colgan, S W J; Erickson, E F; Schultz, A S B; Burton, Michael G.; Colgan, Sean W. J.; Erickson, Edwin F.; Simpson, Janet P.

    2006-01-01

    We present 2micron polarization measurements of positions in the BN region of the Orion Molecular Cloud (OMC-1) made with NICMOS Camera 2 (0.2'' resolution) on HST. Our results are as follows: BN is sim 29% polarized by dichroic absorption and appears to be the illuminating source for most of the nebulosity to its north and up to sim 5'' to its south. Although the stars are probably all polarized by dichroic absorption, there are a number of compact, but non-point-source, objects that could be polarized by a combination of both dichroic absorption and local scattering of star light. We identify several candidate YSOs, including an approximately edge-on bipolar YSO 8.7'' east of BN, and a deeply-embedded variable star. Additional strongly polarized sources are IRc2-B, IRc2-D, and IRc7, all of which are obviously self-luminous at mid-infrared wavelengths and may be YSOs. None of these is a reflection nebula illuminated by a star located near radio source I, as was previously suggested. Other IRc sources are cle...

  2. Hubble Space Telescope Astrometry of the Procyon System

    Science.gov (United States)

    2015-11-10

    diagram is in excellent agreement with theoretical cooling tracks for WDs of its dynamical mass. Its position in the mass– radius plane is also...agreement with theoretical cooling tracks for WDs of its dynamical mass. Its position in the mass??? radius plane is also consistent with theory, assuming a...bias subtraction and flat-fielding applied, but do not include any cosmic -ray removal, geometric correction, or drizzle processing. Each short- and long

  3. Hubble space telescope planetary camera images of NGC 1316

    CERN Document Server

    Shaya, E J; Currie, D G; Faber, S M; Ajhar, E A; Lauer, T R; Groth, E J; Grillmair, C J; Lynds, C R; O'Neil, E J; Shaya, Edward J; Dowling, Daniel M; Currie, Douglas G; Ajhar, Edward A; Lauer, Tod R; Groth, Edward J; Grillmair, Carl J; Lynds, C Roger; O'Neil, Earl J

    1996-01-01

    We present HST Planetary Camera V and I~band images of the central region of the peculiar giant elliptical galaxy NGC~1316. The inner profile is well fit by a nonisothermal core model with a core radius of 0.41" +/- 0.02" (34 pc). At an assumed distance of 16.9 Mpc, the deprojected luminosity density reaches \\sim 2.0 \\times 10^3 L_{\\sun} pc^{-3}. Outside the inner two or three arcseconds, a constant mass-to-light ratio of \\sim 2.2 \\pm 0.2 is found to fit the observed line width measurements. The line width measurements of the center indicate the existence of either a central dark object of mass 2 \\times 10^9 M_{\\sun}, an increase in the stellar mass-to-light ratio by at least a factor of two for the inner few arcseconds, or perhaps increasing radial orbit anisotropy towards the center. The mass-to-light ratio run in the center of NGC~1316 resembles that of many other giant ellipticals, some of which are known from other evidence to harbor central massive dark objects (MDO's). We also examine twenty globular c...

  4. Hubble Space Telescope WFPC-2 Imaging of Cassiopeia A

    CERN Document Server

    Fesen, R A; Chevalier, R A; Borkowski, K J; Gerardy, C L; Lawrence, S S; Van den Bergh, S; Fesen, Robert A.; Morse, Jon A.; Chevalier, Roger A.; Borkowski, Kazimierz J.; Gerardy, Christopher L.; Lawrence, Stephen S.; Bergh, Sidney van den

    2001-01-01

    The young SNR Cassiopeia A was imaged with WFPC-2 through four filters selected to capture the complete velocity range of the remnant's main shell in several important emission lines. Primary lines detected were [O III] 4959,5007, [N II] 6583, [S II] 6716,6731 + [O II] 7319,7330 + [O I] 6300,6364, and [S III] 9069,9532. About 3/4th of the remnant's main shell was imaged in all four filters. Considerable detail is observed in the reverse-shocked ejecta with typical knot scale lengths of 0.2"-0.4" (1 - 2 x 10^16 cm). Both bright and faint emission features appear highly clumped. Large differences in [S III] and [O III] line intensities indicating chemical abundance differences are also seen, particularly in knots located along the bright northern limb and near the base of the northeast jet. A line of curved overlapping filament in the remnant's northwestern rim appears to mark the location of the remnant's reverse shock front in this region. Finger-like ejecta structures elsewhere suggest cases where the revers...

  5. Spitzer Space Telescope Mid-IR Light Curves of Neptune

    CERN Document Server

    Stauffer, J R; Gizis, J E; Rebull, L M; Carey, S J; Krick, J; Ingalls, J G; Lowrance, P; Glaccum, W; Kirkpatrick, J D; Simon, A A; Wong, M H

    2016-01-01

    We have used the Spitzer Space Telescope in February 2016 to obtain high cadence, high signal-to-noise, 17-hour duration light curves of Neptune at 3.6 and 4.5 $\\mu$m. The light curve duration was chosen to correspond to the rotation period of Neptune. Both light curves are slowly varying with time, with full amplitudes of 1.1 mag at 3.6 $\\mu$m and 0.6 mag at 4.5 $\\mu$m. We have also extracted sparsely sampled 18-hour light curves of Neptune at W1 (3.4 $\\mu$m) and W2 (4.6 $\\mu$m) from the WISE/NEOWISE archive at six epochs in 2010-2015. These light curves all show similar shapes and amplitudes compared to the Spitzer light curves but with considerable variation from epoch to epoch. These amplitudes are much larger than those observed with Kepler/K2 in the visible (amplitude $\\sim$0.02 mag) or at 845 nm with the Hubble Space Telescope in 2015 and at 763 nm in 2016 (amplitude $\\sim$ 0.2 mag). We interpret the Spitzer and WISE light curves as arising entirely from reflected solar photons, from higher levels in N...

  6. Measurement of Cosmic Shear with the Space Telescope Imaging Spectrograph

    Science.gov (United States)

    Rhodes, Jason; Refregier, Alexandre; Collins, Nicholas R.; Gardner, Jonathan P.; Groth, Edward J.; Hill, Robert S.

    2004-04-01

    Weak lensing by large-scale structure allows a direct measure of the dark matter distribution. We have used parallel images taken with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope to measure weak lensing, or cosmic shear. We measure the shapes of 26,036 galaxies in 1292 STIS fields and measure the shear variance at a scale of 0.51m. The charge transfer efficiency (CTE) of STIS has degraded over time and introduces a spurious ellipticity into galaxy shapes during the readout process. We correct for this effect as a function of signal-to-noise ratio and CCD position. W