WorldWideScience

Sample records for voyager space probes

  1. The Voyager Journey to Interstellar Space

    Science.gov (United States)

    Stone, E. C.

    Launched in 1977 to explore Jupiter, Saturn, Uranus, and Neptune, the two Voyager spacecraft continued their journeys beyond the planets as they searched for the heliopause, the boundary between the solar wind and the local interstellar medium. After traveling more than 23 billion kilometers, Voyager 1 left the heliosphere on August 25, 2012, and began returning the first in-situ observations of local interstellar space. Voyager 1 found a wall of interstellar plasma beyond the heliopause with a density forty times greater than inside and an interstellar magnetic field that is compressed and wrapped around the outside. Voyager 1 also observed the energy spectrum of low energy galactic cosmic ray protons that are excluded from the heliosphere by solar modulation, finding a peak intensity at ˜30 MeV. that is ten times the maximum intensity at 1 AU that occurs at ˜300 MeV. An overview of the journey and the new aspects of the interaction of the sun and the nearby region of the Milky Way will be discussed.

  2. Voyager.

    Science.gov (United States)

    Education Commission of the States, Denver, CO.

    This paper provides an overview of the Voyager Expanded Learning programs. Initially begun with hands-on, activity-based learning experiences centered around academic themes designed to pique children's interest and motivate them to learn, Voyager has expanded from elementary after- and summer-school programs to include K-8 programs designed for…

  3. Voyages

    OpenAIRE

    Che, Philippe; Cruveillé, Solange; DUTRAIT, Noël; Kaser, Pierre; Kim, Hye-Gyeong; Naudou, Elizabeth; Ngoc, Nguyen Phuong; Pichard-Bertaux, Louise

    2010-01-01

    Le premier numéro d’Impressions d’Extrême-Orient est un volume de traductions inédites de textes en provenance de Chine, de Thaïlande, du Vietnam, de Corée et d’Inde autour du thème du voyage sur lequel revient Noël Dutrait dans un bref avant-propos. Chaque auteur, membre de la jeune équipe « Littératures d’Extrême-Orient, texte et traduction » (JE 2423 – LEO2T, Université de Provence), assure à la fois l’édition scientifique et la traduction des textes présentés dont la version originale est...

  4. Einstein's Symphony: A Gravitational Wave Voyage Through Space and Time

    Science.gov (United States)

    Shapiro Key, Joey; Yunes, Nico; Grimberg, Irene

    2015-01-01

    Einstein's Symphony: A Gravitational Wave Voyage Through Space and Time is a gravitational wave astronomy planetarium show in production by a collaboration of scientists, filmmakers, and artisits from the Center for Gravitational Wave Astonomy (CGWA) at the University of Texas at Brownsville (UTB) and Montana State University (MSU). The project builds on the success of the interdisciplinary Celebrating Einstein collaboration. The artists and scientists who created the A Shout Across Time original film and the Black (W)hole immersive art installation for Celebrating Einstein are teaming with the Museum of the Rockies Taylor Planetarium staff and students to create a new full dome Digistar planetarium show that will be freely and widely distributed to planetaria in the US and abroad. The show uses images and animations filmed and collected for A Shout Across Time and for Black (W)hole as well as new images and animations and a new soundtrack composed and produced by the MSU School of Music to use the full capability of planetarium sound systems. The planetarium show will be narrated with ideas drawn from the Celebrating Einstein danced lecture on gravitational waves that the collaboration produced. The combination of products, resources, and team members assembled for this project allows us to create an original planetarium show for a fraction of the cost of a typical show. In addition, STEM education materials for G6-12 students and teachers will be provided to complement and support the show. This project is supported by the Texas Space Grant Consortium (TSGC), Montana Space Grant Consortium (MSGC), and the American Physical Society (APS).

  5. Lunar Probe Reaches Deep Space

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    @@ China's second lunar probe, Chang'e-2, has reached an orbit 1.5 million kilometers from Earth for an additional mission of deep space exploration, the State Administration for Science, Technology and Industry for National Defense announced.

  6. PROBING THE NATURE OF THE HELIOSHEATH WITH THE NEUTRAL ATOM SPECTRA MEASURED BY IBEX IN THE VOYAGER 1 DIRECTION

    Energy Technology Data Exchange (ETDEWEB)

    Opher, M.; Prested, C. [Astronomy Department, Boston University, 725 Commonwealth Avenue, Boston, MA (United States); McComas, D. J. [Southwest Research Institute, San Antonio, TX 78238 (United States); Schwadron, N. A. [Department of Physics and Space Science Center, University of New Hampshire, Durham, NH 03824 (United States); Drake, J. F., E-mail: mopher@bu.edu [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 (United States)

    2013-10-20

    We are able to show by comparing modeled energetic neutral atoms (ENAs) spectra to those measured by Interstellar Boundary Explorer (IBEX) that the models along the Voyager 1 (V1) trajectory that best agree with the low energy IBEX data include extra heating due to ram and magnetic energy in the quasi-stagnation region or a kappa ion distribution (with κ = 2.0) in the outer heliosheath. The model explored is the multi-ion, multi-fluid (MI-MF) which treats the pick-up ions and the thermal ion fluids with separate Maxwellian distributions. These effects are included ad hoc in the modeled ENA since they are not present in the model. These results indicate that the low energy spectra of ENAs as measured by IBEX is sensitive to the physical nature of the heliosheath and to effects not traditionally present in current global models. Therefore, by comparing the low energy ENA spectra to models, we can potentially probe the heliosheath in locations beyond those probed by V1 and Voyager 2 (V2)

  7. Active probing of space plasmas

    Science.gov (United States)

    Chan, Chang; Silevitch, Michael B.; Villalon, Elena

    1989-09-01

    During the course of the research period our efforts were focused on the following areas: (1) An examination of stochastic acceleration mechanisms in the ionosphere; (2) A study of nonequilibrium dynamics of the coupled magnetosphere - ionosphere system; and (3) Laboratory studies of active space experiments. Reprints include: Dynamics of charged particles in the near wake of a very negatively charged body -- Laboratory experiment and numerical simulation; Laboratory study of the electron temperature in the near wake of a conducting body; New model for auroral breakup during substorms; Substorm breakup on closed field lines; New model for substorm on sets -- The pre-breakup and triggering regimes; Model of the westward traveling surge and the generation of Pi 2 pulsations; Ionospheric electron acceleration by electromagnetic waves near regions of plasma resonances; Relativistic particle acceleration by obliquely propagating electromagnetic fields; Some consequences of intense electromagnetic wave injection into space plasmas.

  8. Space Systems Failures Disasters and Rescues of Satellites, Rockets and Space Probes

    CERN Document Server

    Harland, David M

    2005-01-01

    In the 1960s and 1970s deep space missions were dispatched in pairs in case one was lost in launch or failed during its journey. Following the triumphs of the Viking landings on Mars in 1976 and both Voyagers spacecraft successfully surveying the outer giant planets of the Solar System, it was decided by NASA to cut costs and send out just a single probe. Although Magellan successfully mapped Venus by radar, it suffered from problems during the flight. Then came the loss of Mars Observer, whose engine exploded as it was preparing to enter Mars’ orbit because it was using technology designed for Earth’s satellites and the engine was not suited to spending several months in space. Later came the high-profile losses of Mars Climate Observer and Mars Polar Lander - a consequence of the faster, better, cheaper philosophy introduced by Dan Goldin in 1993. Even the highly successful Galileo mission suffered a major setback when its high-gain antenna (also based on satellite mission suffered a major setback when ...

  9. NASA Facts, Voyager.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC. Educational Programs Div.

    This document is one of a series of publications of the National Aeronautics and Space Administration (NASA) on facts about the exploration of Jupiter and Saturn. This NASA mission consists of two unmanned Voyager spacecrafts launched in August and September of 1977, and due to arrive at Jupiter in 1979. An account of the scientific equipment…

  10. VOYAGE PLANNING

    Directory of Open Access Journals (Sweden)

    Kazimierz SKÓRA

    2016-09-01

    Full Text Available A sea voyage can be divided into three parts with varying degrees of risk: - from the berth at the port of departure to the pilot disembarkation point - from the pilot disembarkation to another pilot embarkation point near the port of call/destination - from the pilot embarkation point to the berth Results of statistical research into ship accidents at sea point to an increased number of incidents and accidents, including groundings, especially in restricted areas. Such areas are often narrow and have limited depths, while their short straight sections require frequent course alterations, often in varying hydrometeorological conditions. Due to all these factors, the voyage has to be carefully planned and all watchkeeping officers have to be well prepared to conduct the ship safely. The article presents the objectives, scope, legal basis and stages in the process of voyage planning. The compliance with the outlined principles will reduce the level of risk in maritime transport.

  11. Voyager picture of Jupiter

    Science.gov (United States)

    1998-01-01

    NASA's Voyager 1 took this picture of the planet Jupiter on Saturday, Jan. 6, the first in its three-month-long, close-up investigation of the largest planet. The spacecraft, flying toward a March 5 closest approach, was 35.8 million miles (57.6 million kilometers) from Jupiter and 371.7 million miles (598.2 million kilometers) from Earth when the picture was taken. As the Voyager cameras begin their meteorological surveillance of Jupiter, they reveal a dynamic atmosphere with more convective structure than had previously been thought. While the smallest atmospheric features seen in this picture are still as large as 600 miles (1,000 kilometers) across, Voyager will be able to detect individual storm systems as small as 3 miles (5 kilometers) at closest approach. The Great Red Spot can be seen near the limb at the far right. Most of the other features are too small to be seen in terrestrial telescopes. This picture was transmitted to the Jet Propulsion Laboratory through the Deep Space Network's tracking station at Madrid, Spain. The Voyager Project is managed for NASA by Caltech's Jet Propulsion Laboratory.

  12. Probing Stellar Dynamics With Space Photometry

    Science.gov (United States)

    García, Rafael A.; Salabert, D.; Ballot, J.; Beck, P. G.; Bigot, L.; Corsaro, E.; Creevey, O.; Egeland, R.; Jiménez, A.; Mathur, S.; Metcalfe, T.; do Nascimento, J.; Pallé, P. L.; Pérez Hernández, F.; Regulo, C.

    2016-08-01

    The surface magnetic field has substantial influence on various stellar properties that can be probed through various techniques. With the advent of new space-borne facilities such as CoRoT and Kepler, uninterrupted long high-precision photometry is available for hundred of thousand of stars. This number will substantially grow through the forthcoming TESS and PLATO missions. The unique Kepler observations -covering up to 4 years with a 30-min cadence- allows studying stellar variability with different origins such as pulsations, convection, surface rotation, or magnetism at several time scales from hours to years. We study the photospheric magnetic activity of solar-like stars by means of the variability induced in the observed signal by starspots crossing the visible disk. We constructed a solar photometric magnetic activity proxy, Sph from SPM/VIRGO/SoHO, as if the Sun was a distant star and we compare it with several solar well-known magnetic proxies. The results validate this approach. Thus, we compute the Sph proxy for a set of CoRoT and Kepler solar-like stars for which pulsations were already detected. After characterizing the rotation and the magnetic properties of 300 solar-like stars, we use their seismic properties to characterize 18 solar analogs for which we study their magnetism. This allows us to put the Sun into context of its siblings.

  13. Accuracy of micro four-point probe measurements on inhomogeneous samples: A probe spacing dependence study

    DEFF Research Database (Denmark)

    Wang, Fei; Petersen, Dirch Hjorth; Østerberg, Frederik Westergaard

    2009-01-01

    In this paper, we discuss a probe spacing dependence study in order to estimate the accuracy of micro four-point probe measurements on inhomogeneous samples. Based on sensitivity calculations, both sheet resistance and Hall effect measurements are studied for samples (e.g. laser annealed samples...... the probe spacing is smaller than 1/40 of the variation wavelength, micro four-point probes can provide an accurate record of local properties with less than 1% measurement error. All the calculations agree well with previous experimental results.......) with periodic variations of sheet resistance, sheet carrier density, and carrier mobility. With a variation wavelength of ¿, probe spacings from 0.0012 to 1002 have been applied to characterize the local variations. The calculations show that the measurement error is highly dependent on the probe spacing. When...

  14. Accuracy of micro four-point probe measurements on inhomogeneous samples: A probe spacing dependence study

    OpenAIRE

    Wang, Fei; Petersen, Dirch Hjorth; Østerberg, Frederik Westergaard; Hansen, Ole

    2009-01-01

    In this paper, we discuss a probe spacing dependence study in order to estimate the accuracy of micro four-point probe measurements on inhomogeneous samples. Based on sensitivity calculations, both sheet resistance and Hall effect measurements are studied for samples (e.g. laser annealed samples) with periodic variations of sheet resistance, sheet carrier density, and carrier mobility. With a variation wavelength of ¿, probe spacings from 0.0012 to 1002 have been applied to characterize the ...

  15. Radiations and space flight; Quand les radiations font partie du voyage

    Energy Technology Data Exchange (ETDEWEB)

    Maalouf, M.; Vogin, G.; Foray, N. [Groupe de Radiobiologie, Inserm U836, Institut des Neurosciences, 38 - Grenoble (France); Maalouf [CNES, Dept. des Sciences de la Vie, 75 - Paris (France); Vogin, G. [Laboratoire de Radiobiologie, EA3738, Faculte de Medecine de Lyon Sud, 69- Oullins (France)

    2011-02-15

    A space flight is submitted to 3 main sources of radiation: cosmic radiation (4 protons/cm{sup 2}/s and 10000 times less for the heaviest particles), solar radiation (10{sup 8} protons/cm{sup 2}/s in the solar wind), the Van Allen belt around the earth: the magnetosphere traps particles and at an altitude of 500 km the proton flux can reach 100 protons/cm{sup 2}/s. If we take into account all the spatial missions performed since 1960, we get an average dose of 400 {mu}Gray per day with an average dose rate of 0.28 {mu}Gray/mn. A significant risk of radiation-induced cancer is expected for missions whose duration is over 250 days.The cataract appears to be the most likely non-cancerous health hazard due to the exposition to comic radiation. Its risk appears to have been under-estimated, particularly for doses over 8 mGray. Some studies on astronauts have shown for some a very strong predisposition for radio-induced cancers: during the reparation phase of DNA breaking due to irradiation, multiple new damages are added by the cells themselves that behave abnormally. (A.C.)

  16. Voyager cartography

    Science.gov (United States)

    Batson, R. M.; Lee, E. M.; Mullins, K. F.

    1987-01-01

    The Jovian and Saturnian satellites are being mapped at several scales from Voyager 1 and 2 data. The maps are especially formatted color mosaics, controlled photomosaics, and airbrush maps. At 1:5,000,000 scale, mapping of Io, Europa, and Ganymede is complete. At 1:15,000,000 scale, mapping of Io and Europa is complete, and mapping of Ganymede is approximately complete. A controlled mosaic of Rhea has been compiled as a Digital Image Model (DIM) in the same format as is being used for Mars. The mosaic is being formatted for publication as a two-sheet set (Lambert Azimuthal Equal Area, Mercator, and Polar Stereographic projections). Magnetic tape copies of the DIM have been distributed to regional Planetary Image Facilities and other interested users. The DIM has a scale of 1/16 degree/pixel, corresponding to approximately 833 m/pixel on Rhea. Details of the status of the various map series are reported quarterly to Planetary Geology Principal Investigators.

  17. Reacting to nuclear power systems in space: American public protests over outer planetary probes since the 1980s

    Science.gov (United States)

    Launius, Roger D.

    2014-03-01

    The United States has pioneered the use of nuclear power systems for outer planetary space probes since the 1970s. These systems have enabled the Viking landings to reach the surface of Mars and both Pioneers 10 and 11 and Voyagers 1 and 2 to travel to the limits of the solar system. Although the American public has long been concerned about safety of these systems, in the 1980s a reaction to nuclear accidents - especially the Soviet Cosmos 954 spacecraft destruction and the Three Mile Island nuclear power plant accidents - heightened awareness about the hazards of nuclear power and every spacecraft launch since that time has been contested by opponents of nuclear energy. This has led to a debate over the appropriateness of the use of nuclear power systems for spacecraft. It has also refocused attention on the need for strict systems of control and rigorous checks and balances to assure safety. This essay describes the history of space radioisotope power systems, the struggles to ensure safe operations, and the political confrontation over whether or not to allow the launch the Galileo and Cassini space probes to the outer planets. Effectively, these efforts have led to the successful flights of 12 deep space planetary probes, two-thirds of them operated since the accidents of Cosmos 954, Three Mile Island, and Chernobyl.

  18. "Voyager": An Educational Card Game

    Science.gov (United States)

    Smith, David Ryan

    2003-01-01

    "Voyager" is an educational card game involving scientific satellites, developed for use in schools with children aged 9 to 13 years. The idea of the game is to improve pupils' knowledge about the large number of scientific satellites there are in space in a fun way, while also practising numeracy skills. Several copies of the game were…

  19. Gravitational Lens: Deep Space Probe Design

    Science.gov (United States)

    2012-03-01

    List of Abbreviations Abbreviation Page FSM Focal Space Mission . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 CMB Cosmic Microwave...concert with the sun’s gravitational lens to image nearby solar systems and/or other pertinent astronomical objects, e.g. the Cosmic Microwave Background...CMB) radiation. 1.2 Thesis Objective In Deep Space Flight and Communications Claudio Maccone uses the mass, radius , mean density, and Schwarzschild

  20. The Evolving Space Weather System—Van Allen Probes Contribution

    Science.gov (United States)

    Zanetti, L. J.; Mauk, B. H.; Fox, N. J.; Barnes, R. J.; Weiss, M.; Sotirelis, T. S.; Raouafi, N.-E.; Kessel, R. L.; Becker, H. N.

    2014-10-01

    The overarching goal and purpose of the study of space weather is clear—to understand and address the issues caused by solar disturbances on humans and technological systems. Space weather has evolved in the past few decades from a collection of concerned agencies and researchers to a critical function of the National Weather Service of NOAA. The general effects have also evolved from the well-known telegraph disruptions of the mid-1800s to modern day disturbances of the electric power grid, communications and navigation, human spaceflight and spacecraft systems. The last two items in this list, and specifically the effects of penetrating radiation, were the impetus for the space weather broadcast implemented on NASA's Van Allen Probes' twin pair of satellites, launched in August of 2012 and orbiting directly through Earth's severe radiation belts. The Van Allen Probes mission, formerly the Radiation Belt Storm Probes (RBSP), was renamed soon after launch to honor the discoverer of Earth's radiation belts at the beginning of the space age, the late James Van Allen (the spacecraft themselves are still referred to as RBSP-A and RBSP-B). The Van Allen Probes are one part of NASA's Living With a Star program formulated to advance the scientific understanding of the connection between solar disturbances, the resulting heliospheric conditions, and their effects on the geospace and Earth environment.

  1. Hyperbolic orbit and its variation of deep-space probe

    Institute of Scientific and Technical Information of China (English)

    LIU; Lin(刘林); WANG; Xin(王歆)

    2003-01-01

    While approaching the target body, the deep-space probe is orbiting hyperbolically before the maneuver. We discuss the variation of perturbed hyperbolic orbit using the method similar to that used in elliptic orbit. Ephemeris calculating and orbit control will benefit from the given analytical solution.

  2. Russian Space Probes Scientific Discoveries and Future Missions

    CERN Document Server

    Harvey, Brian

    2011-01-01

    The Soviet Union began the exploration of space with the launch of Sputnik in 1957, well over 50 years ago, and sent the first probes to the Moon, Mars, and Venus. Less well known is what these probes actually found out. What were the discoveries of Russian space science? What new discoveries may we expect in the future? Who were Russia's most important scientists? Russian Space Probes gives for the first time the definitive history of Soviet-Russian space science, and is the first book to assess the actual achievements of the Russian space program in furthering our knowledge of the Solar System. Among other projects covered are missions such as Elektron, which mapped the Earth's radiation belts; the astrophysical observatories Astron, Kvant, Gamma, and Granat; Proton, which trapped cosmic rays; Prognoz, which measured solar radiation; and the Interball, Aktivny, APEX, and Magion mission in which satellites chased each other in the Earth's magnetic tail. The final part of the book examines the future of Russ...

  3. Voyager-Jupiter radio science data papers

    Science.gov (United States)

    Levy, G. S.; Wood, G. E.

    1980-01-01

    The reduction and interpretation of the radio science data from the Voyager 1 and 2 encounters of the planet Jupiter and its satellites resulted in the preparation of several papers for publication in the special Voyager-Jupiter issue of the Journal of Geophysical Research. The radio science and tracking systems of the Deep Space Network provide the data which makes this research possible. This article lists submitted papers by title, with their authors and with abstracts of their contents.

  4. Gaussian quantum metrology and space-time probes

    CERN Document Server

    Šafránek, Dominik

    2016-01-01

    In this thesis we focus on Gaussian quantum metrology in the phase-space formalism and its applications in quantum sensing and the estimation of space-time parameters. We derive new formulae for the optimal estimation of multiple parameters encoded into Gaussian states. We discuss the discontinuous behavior of the figure of merit - the quantum Fisher information. Using derived expressions we devise a practical method of finding optimal probe states for the estimation of Gaussian channels and we illustrate this method on several examples. We show that the temperature of a probe state affects the estimation generically and always appears in the form of four multiplicative factors. We also discuss how well squeezed thermal states perform in the estimation of space-time parameters. Finally we study how the estimation precision changes when two parties exchanging a quantum state with the encoded parameter do not share a reference frame. We show that using a quantum reference frame could counter this effect.

  5. Voyage to Jupiter.

    Science.gov (United States)

    Morrison, David; Samz, Jane

    This publication illustrates the features of Jupiter and its family of satellites pictured by the Pioneer and the Voyager missions. Chapters included are: (1) "The Jovian System" (describing the history of astronomy); (2) "Pioneers to Jupiter" (outlining the Pioneer Mission); (3) "The Voyager Mission"; (4)…

  6. Barthes's Imaginary Voyages

    Directory of Open Access Journals (Sweden)

    Lynn A. Higgins

    1981-01-01

    Full Text Available Reading L 'Empire des signes and Alors la Chine as points of departure, the article explores a network of reciprocal images of the text as voyage and the voyage as text, with Barthes as a self-styled, disinherited ethnographer/traveler.

  7. Solar System Voyage

    Science.gov (United States)

    Brunier, Serge

    2002-11-01

    In the last few decades, the exploration of our solar system has revealed fascinating details about the worlds that lie beyond our Earth. This lavishly illustrated book invites the reader on a journey through the solar system. After locating our planetary system in the Universe, Brunier describes the Sun and its planets, the large satellites, asteroids, and comets. Photographs and information taken from the latest space missions allow readers to experience spectacular scenes: the lunar plains scarred by asteroid impacts, the frozen deserts of Mars and Europa, the continuously erupting volcanoes of Io and the giant geysers of Triton, the rings of Saturn and the clouds of Venus and Titan, and the powerful crash of the comet Shoemaker-Levy into Jupiter. Inspired by the extraordinary photographs and incisive text, readers of Solar System Voyage will gain a greater appreciation of the hospitable planet we call home. Serge Brunier is chief editor of the journal Ciel et Espace, a photojournalist, and the author of many nonfiction books aimed at both specialists and the general public. His previous books include Space Odyssey (Cambridge, 2002), Glorious Eclipses with Jean-Pierre Luminet (Cambridge, 2000), and Majestic Universe (Cambridge, 1999).

  8. Probing electron correlation and nuclear dynamics in Momentum Space

    Energy Technology Data Exchange (ETDEWEB)

    Deleuze, M S; Hajgato, B; Morini, F; Knippenberg, S, E-mail: michael.deleuze@uhasselt.b [Research Group of Theoretical Chemistry, Department SBG, Hasselt University, Agoralaan, Gebouw D, B3590 Diepenbeek (Belgium)

    2010-02-01

    Orbital imaging experiments employing Electron Momentum Spectroscopy are subject to many complications, such as distorted wave effects, conformational mobility in the electronic ground state, ultra-fast nuclear dynamics in the final state, or a dispersion of the ionization intensity over electronically excited (shake-up) configurations of the cation. The purpose of the present contribution is to illustrate how a proper treatment of these complications enables us to probe in momentum space the consequences of electron correlation and nuclear dynamics in neutral and cationic states.

  9. UPF based autonomous navigation scheme for deep space probe

    Institute of Scientific and Technical Information of China (English)

    Li Peng; Cui Hutao; Cui Pingyuan

    2008-01-01

    The autonomous "celestial navigation scheme" for deep space probe departing from the earth and the autonomous "optical navigation scheme" for encountering object celestial body are presented. Then, aiming at the conditions that large initial estimation errors and non-Gaussian distribution of state or measurement errors may exist in orbit determination process of the two phases, UPF (unscented particle filter) is introduced into the navigation schemes. By tackling nonlinear and non-Gaussian problems, UPF overcomes the accuracy influence brought by the traditional EKF (extended Kalman filter), UKF (unscented Kalman filter), and PF (particle filter) schemes in approximate treatment to nonlinear and non-Gaussian state model and measurement model. The numerical simulations demonstrate the feasibility and higher accuracy of the UPF navigation scheme.

  10. Voyager 1 'Blue Movie'

    Science.gov (United States)

    2000-01-01

    This is the original Voyager 'Blue Movie' (so named because it was built from Blue filter images). It records the approach of Voyager 1 during a period of over 60 Jupiter days. Notice the difference in speed and direction of the various zones of the atmosphere. The interaction of the atmospheric clouds and storms shows how dynamic the Jovian atmosphere is.As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 66 images taken once every Jupiter rotation period (about 10 hours). This time-lapse movie uses images taken every time Jupiter longitude 68W passed under the spacecraft. These images were acquired in the Blue filter from Jan. 6 to Feb. 3 1979. The spacecraft flew from 58 million kilometers to 31 million kilometers from Jupiter during that time.This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  11. Voyager Outreach Compilation

    Science.gov (United States)

    1998-01-01

    This NASA JPL (Jet Propulsion Laboratory) video presents a collection of the best videos that have been published of the Voyager mission. Computer animation/simulations comprise the largest portion of the video and include outer planetary magnetic fields, outer planetary lunar surfaces, and the Voyager spacecraft trajectory. Voyager visited the four outer planets: Jupiter, Saturn, Uranus, and Neptune. The video contains some live shots of Jupiter (actual), the Earth's moon (from orbit), Saturn (actual), Neptune (actual) and Uranus (actual), but is mainly comprised of computer animations of these planets and their moons. Some of the individual short videos that are compiled are entitled: The Solar System; Voyage to the Outer Planets; A Tour of the Solar System; and the Neptune Encounter. Computerized simulations of Viewing Neptune from Triton, Diving over Neptune to Meet Triton, and Catching Triton in its Retrograde Orbit are included. Several animations of Neptune's atmosphere, rotation and weather features as well as significant discussion of the planet's natural satellites are also presented.

  12. Probing critical surfaces in momentum space using real-space entanglement entropy: Bose versus Fermi

    Science.gov (United States)

    Lai, Hsin-Hua; Yang, Kun

    2016-03-01

    A codimension-one critical surface in momentum space can be either a familiar Fermi surface, which separates occupied states from empty ones in the noninteracting fermion case, or a novel Bose surface, where gapless bosonic excitations are anchored. The presence of such surfaces gives rise to logarithmic violation of entanglement entropy area law. When they are convex, we show that the shape of these critical surfaces can be determined by inspecting the leading logarithmic term of real-space entanglement entropy. The fundamental difference between a Fermi surface and a Bose surface is revealed by the fact that the logarithmic terms in entanglement entropies differ by a factor of 2: SlogBose=2 SlogFermi , even when they have identical geometry. Our method has remarkable similarity with determining Fermi surface shape using quantum oscillation. We also discuss possible probes of concave critical surfaces in momentum space.

  13. Voyager Approaches Final Frontier

    Science.gov (United States)

    2003-01-01

    An artist's concept illustrates the positions of the Voyager spacecraft in relation to structures formed around our Sun by the solar wind. Also illustrated is the termination shock, a violent region the spacecraft must pass through before reaching the outer limits of the solar system. At the termination shock, the supersonic solar wind abruptly slows from an average speed of 400 kilometers per second to less than 100 kilometer per second (900,000 to less than 225,000 miles per hour). Beyond the termination shock is the solar system's final frontier, the heliosheath, a vast region where the turbulent and hot solar wind is compressed as it presses outward against the interstellar wind that is beyond the heliopause. A bow shock likely forms as the interstellar wind approaches and is deflected around the heliosphere, forcing it into a teardrop-shaped structure with a long, comet-like tail.The exact location of the termination shock is unknown, and it originally was thought to be closer to the Sun than Voyager 1 currently is. As Voyager 1 cruised ever farther from the Sun, it confirmed that all the planets are inside an immense bubble blown by the solar wind and the termination shock was much more distant.

  14. 46 CFR Sec. 2 - Voyage numbers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Voyage numbers. Sec. 2 Section 2 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 2 Voyage numbers. (a... designation and voyage number, as NSA-1/ABC-1. (b) The continuity of NSA voyage numbers shall not change...

  15. Space Weather Operation at KASI with Van Allen Probes Beacon Signals

    Science.gov (United States)

    Lee, J.; Kim, K. C.; Romeo, G.; Ukhorskiy, S.; Sibeck, D. G.; Kessel, R.; Mauk, B.; Giles, B. L.; Gu, B. J.; Lee, H.

    2016-12-01

    The Van Allen Probes are the first NASA mission broadcasting real time data in the Earth's radiation belts for space weather operation. Korea Astronomy and Space Science Institute has contributed in data receiving from Van Allen Probes with 7 m satellite tracking antenna since 2012 and used the data for space weather operation. It takes approximately 15 minutes from measurements to produce Level 1 data. In this study, we show how the Van Allen Probes data is handled for monitoring space weather conditions at geostationary orbit (GEO) by highlighting the Saint Patrick's Day storm occurred in 2015. During storm time, Probe-A data shows a significant increase of relativistic electron flux at L=3. The electrons diffuse out and results in large increase of > 2MeV electron flux on GEO. By monitoring the radial distribution of energetic electrons, we could predict relativistic electron enhancement events that potentially threat satellite operation. We conclude that the combination of Van Allen Probes and NOAA-GOES data can provide improved space environment information to geostationary satellite operators. In addition, the lessons learned from Van Allen Probes are that more data receiving sites are necessary and data connections should be monitored for operational data service.

  16. 46 CFR 80.15 - Ocean voyage.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Ocean voyage. 80.15 Section 80.15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS DISCLOSURE OF SAFETY STANDARDS AND COUNTRY OF REGISTRY § 80.15 Ocean voyage. An ocean voyage for the purposes of this part means: A voyage on any body...

  17. 46 CFR 122.503 - Voyage plan.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Voyage plan. 122.503 Section 122.503 Shipping COAST... Emergencies § 122.503 Voyage plan. (a) The master of the following vessels shall prepare a voyage plan: (1) A... United States Great Lakes port from a Canadian Great Lakes port. (b) The voyage plan required...

  18. Detecting 3D vegetation structure with the Galileo space probe: Can a distant probe detect vegetation structure on Earth?

    CERN Document Server

    Doughty, Christopher E

    2016-01-01

    Sagan et al. (1993) used the Galileo space probe data and first principles to find evidence of life on Earth. Here we ask whether Sagan et al. (1993) could also have detected whether life on Earth had three-dimensional structure, based on the Galileo space probe data. We reanalyse the data from this probe to see if structured vegetation could have been detected in regions with abundant photosynthetic pigments through the anisotropy of reflected shortwave radiation. We compare changing brightness of the Amazon forest (a region where Sagan et al. (1993) noted a red edge in the reflectance spectrum, indicative of photosynthesis) as the planet rotates to a common model of reflectance anisotropy and found measured increase of surface reflectance of 0.019 versus a 0.007 predicted from only anisotropic effects. We hypothesize the difference was due to minor cloud contamination. However, the Galileo dataset had only a small change in phase angle (sun-satellite position) which reduced the observed anisotropy signal an...

  19. Voyager to the Seventh Planet.

    Science.gov (United States)

    Gold, Michael

    1986-01-01

    Presents recent findings obtained by the Voyager 2 mission on Uranus. Updates information on the planet's moons, rings, atmosphere, and magnetic field. Illustrations and diagrams of selected aspects of Uranus are included. (ML)

  20. Probing scalar tensor theories for gravity in Redshift-Space

    CERN Document Server

    Sabiu, Cristiano G; Llinares, Claudio; Park, Changbom

    2016-01-01

    We present measurements of the spatial clustering statistics in redshift space of various scalar field modified gravity simulations. We utilise the two-point and the three-point correlation functions to quantify the spatial distribution of dark matter halos within these simulations and thus discern between the models. We compare $\\Lambda$CDM simulations to various modified gravity scenarios and find consistency with previous work in terms of 2-point statistics in real and redshift-space. However using higher order statistics such as the three-point correlation function in redshift space we find significant deviations from $\\Lambda$CDM hinting that higher order statistics may prove to be a useful tool in the hunt for deviations from General Relativity.

  1. Probing chemical space with alkaloid-inspired libraries

    Science.gov (United States)

    McLeod, Michael C.; Singh, Gurpreet; Plampin, James N.; Rane, Digamber; Wang, Jenna L.; Day, Victor W.; Aubé, Jeffrey

    2014-02-01

    Screening of small-molecule libraries is an important aspect of probe and drug discovery science. Numerous authors have suggested that bioactive natural products are attractive starting points for such libraries because of their structural complexity and sp3-rich character. Here, we describe the construction of a screening library based on representative members of four families of biologically active alkaloids (Stemonaceae, the structurally related cyclindricine and lepadiformine families, lupin and Amaryllidaceae). In each case, scaffolds were based on structures of the naturally occurring compounds or a close derivative. Scaffold preparation was pursued following the development of appropriate enabling chemical methods. Diversification provided 686 new compounds suitable for screening. The libraries thus prepared had structural characteristics, including sp3 content, comparable to a basis set of representative natural products and were highly rule-of-five compliant.

  2. Probing the face-space of individuals with prosopagnosia.

    Science.gov (United States)

    Nishimura, Mayu; Doyle, Jaime; Humphreys, Kate; Behrmann, Marlene

    2010-05-01

    A useful framework for understanding the mental representation of facial identity is face-space (Valentine, 1991), a multi-dimensional cognitive map in which individual faces are coded relative to the average of previously encountered faces, and in which the distance among faces represents their perceived similarity. We examined whether individuals with prosopagnosia, a disorder characterized by an inability to recognize familiar faces despite normal visual acuity and intellectual abilities, evince behavior consistent with this underlying representational schema. To do so, we compared the performance of 6 individuals with congenital prosopagnosia (CP), with a group of age- and gender-matched control participants in a series of experiments involving judgments of facial identity. We used digital images of male and female faces and morphed them to varying degrees relative to an average face, to create caricatures, anti-caricatures, and anti-faces (i.e. faces of the opposite identity). Across 5 behavioral tasks, CP individuals' performance was similar to that of the control group and consistent with the face-space framework. As a test of the sensitivity of our measures in revealing face processing abnormalities, we also tested a single acquired prosopagnosic (AP) individual, whose performance on the same tasks deviated significantly from the control and CP groups. The findings suggest that, despite an inability to recognize individual identities, CPs perceive faces in a manner consistent with norm-based coding of facial identity, although their representation is likely supported by a feature-based strategy. We suggest that the apparently normal posterior cortical regions, including the fusiform face area, serve as the neural substrate for at least a coarse, feature-based face-space map in CP and that their face recognition impairment arises from the disconnection between these regions and more anterior cortical sites.

  3. Astrometric Gravitation Probe: a space mission concept for fundamental physics

    Science.gov (United States)

    Vecchiato, Alberto; Fienga, Agnes; Gai, Mario; Lattanzi, Mario G.; Riva, Alberto; Busonero, Deborah

    2015-08-01

    Modern technological developments have pushed the accuracy of astrometric measurements in the visible band down to the micro-arcsec level. This allows to test theories of gravity in the weak field limit to unprecedented level, with possible consequences spanning from the validity of fundamental physics principles, to tests of theories describing cosmological and galactic dynamics without resorting to Dark Matter and Dark Energy.This is the main goal of Astrometric Gravitation Probe (AGP) mission, which will be achieved by highly accurate astrometric determination of light deflection (as a modern rendition of the Dyson, Eddington, and Robertson eclipse experiment of 1919), aberration, and of the orbits of selected Solar System objects, with specific reference to the excess shift of the pericentre effect.The AGP concept was recently proposed for the recent call for ESA M4 missions as a collaboration among several scientists coming from many different European and US institutions. Its payload is based on a 1.15 m diameter telescope fed through a coronagraphic system by four fields, two set in symmetric positions around the Sun, and two in the opposite direction, all imaged on a CCD detector. Large parts of the instrument are common mode to all fields. The baseline operation mode is the scan of the ±1.13 deg Ecliptic strip, repeated for a minimum of 3 years and up to an optimal duration of 5 years. Operations and calibrations are simultaneous, defined in order to ensure common mode instrumental effects, identified and removed in data reduction. The astrometric and coronagraphic technologies build on the heritage of Gaia and Solar Orbiter.We review the mission concept and its science case, and discuss how this measurement concepts can be scaled to different mission implementations.

  4. Probing Interstellar Dust With Space-Based Coronagraphs

    CERN Document Server

    Turner, N J; Breckinridge, J B

    2008-01-01

    We show that space-based telescopes such as the proposed Terrestrial Planet Finder Coronagraph will be able to detect the light scattered by the interstellar grains along lines of sight passing near stars in our Galaxy. The relative flux of the scattered light within one arcsecond of a star at 100 pc in a uniform interstellar medium of 0.1 H atoms cm^-3 is about 10^-7. The halo increases in strength with the distance to the star and is unlikely to limit the coronagraphic detection of planets around the nearest stars. Grains passing within 100 AU of Sun-like stars are deflected by radiation, gravity and magnetic forces, leading to features in the scattered light that can potentially reveal the strength of the stellar wind, the orientation of the stellar magnetic field and the relative motion between the star and the surrounding interstellar medium.

  5. Means to remove electrode contamination effect of Langmuir probe measurement in space

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, K.-I.; Lee, C. H.; Fang, H. K.; Cheng, C. Z. [Plasma and Space Science Center, National Cheng Kung University, No.1 Ta-Hsueh Rd., Tainan 70101, Taiwan (China)

    2012-05-15

    Precaution to remove the serious effect of electrode contamination in Langmuir probe experiments has not been taken in many space measurements because the effect is either not understood or ignored. We stress here that one should pay extra attention to the electrode contamination effect to get accurate and reliable plasma measurements so that the long time effort for sounding rocket/satellite missions does not end in vain or becomes less fruitful. In this paper, we describe two main features of voltage-current characteristic curves associated with the contaminated Langmuir probe, which are predicted from the equivalent circuit model, which we proposed in 1970's. We then show that fast sweeping dc Langmuir probes can give reliable results in the steady state regime. The fast sweeping probe can also give reliable results in transient situations such as satellite moves through plasma bubble in the ionosphere where the electron density drastically changes. This fact was first confirmed in our laboratory experiment.

  6. Récits de voyage

    OpenAIRE

    Efthymiou, Loukia

    2011-01-01

    La présente recherche prend appui d’une part sur les textes viatiques d’un groupe de voyageuses françaises appartenant au milieu de l’enseignement secondaire féminin et d’autre part sur leurs dossiers personnels conservés aux Archives Nationales. Le profil socioprofessionnel de ces éducatrices commande le caractère spécifique de leur voyage (pays de destination, motif du voyage, contraintes temporelles et financières) et de son écriture (discours qui sous-tendent le récit). Par la publication...

  7. The Context for IMAP: Voyager and INCA Observations of the Heliosheath at E > 5 keV

    Science.gov (United States)

    Krimigis, Stamatios M.

    2016-04-01

    The basic premise of the proposed Interstellar Mapping and Acceleration Probe (IMAP) is detailed scientific understanding of the Heliosheath (HS) and beyond, a region of space explored in situ by Voyager 1 (V1) since 2004, Voyager 2 (V2) since 2007, and remotely via energetic neutral atoms (ENA) by the Cassini/INCA (Ion and Neutral CAmera) since 2003 and IBEX since 2009. The IMAP instrumentation proposed for this purpose combines and extends the IBEX and INCA ENA energy ranges (0.3- 20 keV and 3-200 keV, for low and high energy, respectively). All three missions-Voyagers, Cassini/INCA, and IBEX- have made discovery-class measurements in the HS, the Voyagers providing in situ ion intensities at E > 30 keV, while INCA images ENA in the range 5 INCA ENA allows for the possibility of observing the intensity and time evolution of ions in the HS, thought to give rise to the ENAs via charge-exchange, and the resultant ENA images in the inner heliosphere and their spatial and/or temporal variability. Unfortunately, no such "ground truth" ion measurements are possible at Voyager in the ENA energy range imaged by IBEX. Some of the key findings from the Voyager and Cassini/INCA measurements are as follows: (1) The HS contains a hot plasma population that carries a substantial part (30-50 %) of the total pressure at E > 5 keV, the rest residing below that range, resulting in a beta (particle/magnetic pressure) always > 1, typically >10. (2) The width of the HS in the direction of V1 is ~ 30 AU, but is thought to be larger (40-70 AU) in the southern ecliptic where V2 currently travels.. (3) The ENA intensities at E > 5 keV exhibit a correlation with the solar cycle (SC) over the period 2003 to 2015, with minimum intensities in the anti-nose direction observed ~ 1.5 yrs after solar minimum followed by a recovery thereafter. (4) The in situ ion measurements at V2 within the HS also show a similar SC dependence. The totality of the observations, together with the near

  8. Academy of Program/Project & Engineering Leadership: Shared Voyage: Learning and Unlearning from Remarkable Projects

    Data.gov (United States)

    National Aeronautics and Space Administration — Shared Voyage is about four remarkable projects:the Advanced Composition Explorer (NASA), the Joint Air-to-Surface Standoff Missile (U.S. Air Force), the Pathfinder...

  9. Deux voyages d’hiver

    Directory of Open Access Journals (Sweden)

    Etienne Barilier

    2011-12-01

    Full Text Available La relation entre la vie et l’œuvre, chez un artiste, n’est jamais une simple relation de cause à effet. L’on peut trouver, à l’origine du Voyage d’hiver de Schubert, comme à celle de la Rhapsodie pour alto de Brahms (dont les paroles, tirées d’un poème de Goethe, racontent elles aussi un voyage hivernal, des douleurs amoureuses. Mais ces deux œuvres transcendent les événements biographiques dont elles sont issues. échappant au narcissisme du moi romantique, elles traduisent deux expériences du temps, cyclique ou progressif, racontent deux voyages spirituels. La douleur d’exister y devient pure présence de la vie, et récit purifié.For an artist, the link between life and work is never a simple cause-effect relationship. The loving pain can be considered as the source of Schubert's Winterreise and of the Brahms Alto Rhapsody as well (the latter being based also upon a poem by Goethe, which tells also a winter journey. But these works transcend the life events from which they arise. Beyond the narcissism of the romantic self, they reflect two experiences of time, cyclical or progressive, and they tell two spiritual journeys. The pain of existence becomes a pure presence of life, and a purified story.

  10. VOYAGER 1 NEAR THE HELIOPAUSE

    Energy Technology Data Exchange (ETDEWEB)

    Borovikov, S. N.; Pogorelov, N. V., E-mail: nikolai.pogorelov@uah.edu [Center for Space Physics and Aeronomic Research, The University of Alabama in Huntsville, Huntsville, AL 35805 (United States)

    2014-03-01

    Recent observations from the Voyager 1 spacecraft show that it is sampling the local interstellar medium (LISM). This is quite surprising because no realistic, steady-state model of the solar wind (SW) interaction with the LISM gives an inner heliosheath width as narrow as ∼30 AU. This includes models that assume a strong redistribution of the ion energy to the tails in the pickup ion distribution function. We show that the heliopause (HP), which separates the SW from the LISM, is not a smooth tangential discontinuity, but rather a surface subject to Rayleigh-Taylor-type instabilities which can result in LISM material penetration deep inside the SW. We also show that the HP flanks are always subject to a Kelvin-Helmholtz instability. The instabilities are considerably suppressed near the HP nose by the heliospheric magnetic field in steady-state models, but reveal themselves in the presence of solar cycle effects. We argue that Voyager 1 may be in one such instability region and is therefore observing plasma densities much higher than those in the pristine SW. These results may explain the early penetration of Voyager 1 into the LISM. They also show that there is a possibility that the spacecraft may start sampling the SW again before it finally leaves the heliosphere.

  11. New developments at Hunveyor and Husar space probe model constructions in Hungarian Universities and Colleges: status report of 2008

    Science.gov (United States)

    Hegzi, S.; Bérczi, Sz.; Hudoba, Gy.; Magyar, I.; Lang, A.; Istenes, Z.; Weidinger, T.; Tepliczky, I.; Varga, T.; Hargitai, H.

    2008-09-01

    Introduction Hunveyor and Husar space probe models are the main school robotics program in Hungary in the last decade initiated by our Cosmic Materials Space research Group (CMSRG). As a new form of planetary science education in Hungary students build their lander and rover robots and test them on test tables, carry out simulations, and go with their instruments to field works of planetary geology analog sites. Recently 10 groups work in this program and here is a status report about the new results. Planetary robot construction and simulations steps We summarized in 10 steps the main "constructional and industrial research and technology" description of planetary material studying and collecting by space probes (landers, rovers). We focused on the activity we began and teach to carry out at those steps. (Main planets considered were the Moon and Mars): 1. Reconnaissance and survey of the surface of a planet by orbital space probes (i.e. Lunar Orbiter, MGS, MRO etc.) Our studies: photogeology, geomorphology, preparations to cartography. 2. Mapping of the surface of the selected planet with geographical and stratigraphical methods. We (CMSRG) prepared thematic maps on Moon, Mercury, Mars, Venus [1] and Atlas (3) in the series [2,3]. 3. Identification of various surface materials by albedo, spectroscopic [4], thermal IR, identification and selection of the target sites. (in terrestrial analog sites during field works) 4. Planning the space probe system lander and rover working together (MPF-Sojourner type assembly). Planning of the Hunveyor and Husar models. 5. Construction and manufacturing lander and rover units. All Hunveyor groups built their models [5]. 6. Launching and traveling the space probes to the planetary surface. (No rocket building, we simulate [6] some events during the voyage only). 7. Measuring the planetary surface environment on the surface of target planet [7]. (CMSRG) groups carry out test-table measurements [8] and simulations, and later they

  12. Voyager: The grandest tour. The mission to the outer planets

    Science.gov (United States)

    1991-04-01

    A history and general accomplishments of the Voyager 1 and 2 missions to the outer planets are presented. Over the course of 12 years, these spacecraft drew back the curtain on nearly half the solar system. They brought into sharp focus the faces of the four giant outer planets - Jupiter, Saturn, Uranus, and Neptune - and their families of disparate moons. The Voyagers showed us unimagined worlds: frozen beauty in the rings of Saturn, and molten violence in the explosive sulfur volcanoes on Jupiter's moon Io. They brought us close-ups of the florid and intricate storms of Jupiter itself. Voyager 2 went on to reveal the peculiarities of cockeyed Uranus and its equally skewed rings and moons. Then finally, Neptune, nearly invisible from earth, was unveiled in all its big, blue splendor, circled by shadowy rings and a bright pastel moon called Triton. Both Voyagers are headed toward the outer boundary of the solar system in search of the heliopause, the region where the sun's influence wanes and the beginning of interstellar space can be sensed.

  13. Voyager, a journey into the unknown - an interview with Ed Stone (Caltech), Voyager project scientist

    CERN Multimedia

    CERN Video productions; Piotr Traczyk

    2012-01-01

    Voyager, a journey into the unknown - an interview with Ed Stone (Caltech), Voyager project scientist, interviewed on the 100th anniversary of the discovery of Cosmic Rays conference, Spaceparts, at CERN in November 2012.

  14. ULF Waves Observed at MAGDAS Stations as Probes for Litho-Space Weather Study

    Science.gov (United States)

    Yumoto, Kiyohumi

    K.Yumoto, Space Environment Research Center (SERC), Kyushu University started the MAGDAS Project effectively in May of 2005, with the installation of the first unit in Hualien, Taiwan (Yumoto et al., 2006, 2007). Since then, over 50 units have been deployed around the world. They are concentrated along three chains: (1) North and South of Japan (the so-called "210o Magnetic Meridian Chain"), (2) Dip Equator Chain, and (3) Africa Chain (the so-called "96o Magnetic Meridian Chain"). The main goals of MAGDAS project are: (1) study magnetospheric pro-cesses by distinguishing between temporal changes and spatial variations in the phenomena, (2) clarify global structures and propagation characteristics of magnetospheric variations from higher to equatorial latitudes, and (3) understand global generation mechanisms of the Solar-Terrestrial phenomena (see Yumoto, 2004). From MAGDAS observations, ULF waves are found to be used as good probes for litho-space weather study in developing and developed countries. In the present paper, we will introduce the following examples: Pc 5 magnetic amplitudes at lower-latitude MAGDAS station show a linear relation with the solar wind velocity, thus we can use the Pc 5 amplitudes as a monitoring probe of the solar wind velocity. Pc 3-4 magnetic pulsations have skin depth comparable with the depth of epicentre of earthquakes in the lithosphere. Therefore, we can use Pc 3-4 as a probe for detecting ULF anomaly and precursors associated with great earthquakes. Pi 2 magnetic pulsations are observed globally at MAGDAS stations located at high, middle, low, and equatorial latitudes in night-and day-time. We can use the Pi 2s as a good indicator of onsets of magnetospheric substorms. Sudden commencements (sc), sudden impulse (si), and solar flare effects (sfe) create magnetic variations at MAGDAS stations. Therefore, MAGDAS data can be used as a probe of interplanetary shocks and interplanetary discontinuities in the solar wind, and solar flare

  15. Science with the space-based interferometer LISA. IV: probing inflation with gravitational waves

    Science.gov (United States)

    Bartolo, Nicola; Caprini, Chiara; Domcke, Valerie; Figueroa, Daniel G.; Garcia-Bellido, Juan; Chiara Guzzetti, Maria; Liguori, Michele; Matarrese, Sabino; Peloso, Marco; Petiteau, Antoine; Ricciardone, Angelo; Sakellariadou, Mairi; Sorbo, Lorenzo; Tasinato, Gianmassimo

    2016-12-01

    We investigate the potential for the LISA space-based interferometer to detect the stochastic gravitational wave background produced from different mechanisms during inflation. Focusing on well-motivated scenarios, we study the resulting contributions from particle production during inflation, inflationary spectator fields with varying speed of sound, effective field theories of inflation with specific patterns of symmetry breaking and models leading to the formation of primordial black holes. The projected sensitivities of LISA are used in a model-independent way for various detector designs and configurations. We demonstrate that LISA is able to probe these well-motivated inflationary scenarios beyond the irreducible vacuum tensor modes expected from any inflationary background.

  16. Science with the space-based interferometer LISA. IV: Probing inflation with gravitational waves

    CERN Document Server

    Bartolo, Nicola; Domcke, Valerie; Figueroa, Daniel G; Garcia-Bellido, Juan; Guzzetti, Maria Chiara; Liguori, Michele; Matarrese, Sabino; Peloso, Marco; Petiteau, Antoine; Ricciardone, Angelo; Sakellariadou, Mairi; Sorbo, Lorenzo; Tasinato, Gianmassimo

    2016-01-01

    We investigate the potential for the LISA space-based interferometer to detect the stochastic gravitational wave background produced from different mechanisms during inflation. Focusing on well-motivated scenarios, we study the resulting contributions from particle production during inflation, inflationary spectator fields with varying speed of sound, effective field theories of inflation with specific patterns of symmetry breaking and models leading to the formation of primordial black holes. The projected sensitivities of LISA are used in a model-independent way for various detector designs and configurations. We demonstrate that LISA is able to probe these well-motivated inflationary scenarios beyond the irreducible vacuum tensor modes expected from any inflationary background.

  17. Ciguri. Voyage(s au pays des Tarahumaras

    Directory of Open Access Journals (Sweden)

    Carasco, Raymonde

    1998-12-01

    Full Text Available The author discusses the problems involved in ethnographic film-making, specifically in the making of a film discourse of one's own. She deems it necessary to construct an ideational «scenario» in which to capture the múltiple details of the reality that is to be filmed. The visual representation of Antonin Artaud's Voyage of 1936 to Tarahumara territory, in México, is a case in point: a unique project which combines literature and film-making, film-making and ethnology.El ensayo presenta la problemática que significa la realización de un film etnográfico y, específicamente, la construcción de un discurso fílmico propio, por lo que se propone que es necesaria la construcción de un «escenario» ideacional que permita captar los múltiples detalles de la realidad que se quiere filmar. El artículo se organiza a partir de un proyecto singular, a caballo entre la literatura y el cine, entre el cine y la etnología, que ha consistido en traducir en imágenes el Voyage que Antonin Artaud hizo a México en 1936, en concreto, al país de los Tarahumaras.

  18. On the Transfer and Control of Space Probes Around the L1 Point of the Sun-Earth+Moon System

    Science.gov (United States)

    Hou, Xi-Yun; Liu, Lin

    2008-01-01

    The motion around the collinear libration points in the restricted three body problem is unstable. But there exist conditionally stable periodic orbits around these points. Special-purpose space probes located in the vicinity of these points (e.g., ISEE-3, SOHO) can benefit from this dynamical property, in regard to maintaining the orbit in position and the energy required of placing the probe in position. As an example, we study in this paper the launch and orbital control of a space probe around the L1 libration point in the system consisting of the Sun and the Earth-Moon. We present some theoretical and numerical simulations' results, which may serve as a basis for the realization of such a space probe in future.

  19. Constraints on dark photon dark matter using Voyager magnetometric survey

    CERN Document Server

    Pignol, G; Guigue, M; Rebreyend, D; Voirin, B

    2015-01-01

    The dark photon, an new hypothetical light spin 1 field, constitutes a well-motivated dark matter candidate. It manifests as an oscillating electric field with a fixed direction, which can be observed in magnetometric records. In this letter, we use magnetometer data from the Voyager probes to look for the dark photon in the 10^-24 eV to 10^-19 eV mass range, corresponding to frequencies between 10^-9 Hz and 10^-4 Hz. We also discuss the sensitivity of possible future SQUID magnetometry experiments.

  20. Interstellar Mapping and Acceleration Probe (IMAP) - Its Time Has Come!

    Science.gov (United States)

    Schwadron, N.; Kasper, J. C.; Mewaldt, R. A.; Moebius, E.; Opher, M.; Spence, H. E.; Zurbuchen, T.

    2014-12-01

    Our piece of cosmic real-estate, the heliosphere, is the domain of all human existence -- an astrophysical case-history of the successful evolution of life in a habitable system. By exploring our global heliosphere and its myriad interactions, we develop key physical knowledge of the interstellar interactions that influence exoplanetary habitability as well as the distant history and destiny of our solar system and world. IBEX was the first mission to explore the global heliosphere and in concert with Voyager 1 and Voyager 2 is discovering a fundamentally new and uncharted physical domain of the outer heliosphere. The enigmatic IBEX ribbon is an unanticipated discovery demonstrating that much of what we know or think we understand about the outer heliosphere needs to be revised. The next quantum leap enabled by IMAP will open new windows on the frontier of Heliophysics at a time when the space environment is rapidly evolving. IMAP with 100 times the combined resolution and sensitivity of IBEX will discover the substructure of the IBEX ribbon and will reveal in unprecedented resolution global maps of our heliosphere. The remarkable synergy between IMAP, Voyager 1 and Voyager 2 will remain for at least the next decade as Voyager 1 pushes further into the interstellar domain and Voyager 2 moves through the heliosheath. Voyager 2 moves outward in the vicinity of the IBEX ribbon and its plasma measurements will create singular opportunities for discovery in the context of IMAP's global measurements. IMAP, like ACE before it, will be a keystone of the Heliophysics System Observatory by providing comprehensive cosmic ray, energetic particle, pickup ion, suprathermal ion, neutral atom, solar wind, solar wind heavy ion, and magnetic field observations to diagnose the changing space environment and understand the fundamental origins of particle acceleration. Thus, IMAP is a mission whose time has come. IMAP is the highest ranked next Solar Terrestrial Probe in the Decadal

  1. Voyager 2 Jupiter Eruption Movie

    Science.gov (United States)

    2000-01-01

    This movie records an eruptive event in the southern hemisphere of Jupiter over a period of 8 Jupiter days. Prior to the event, an undistinguished oval cloud mass cruised through the turbulent atmosphere. The eruption occurs over avery short time at the very center of the cloud. The white eruptive material is swirled about by the internal wind patterns of the cloud. As a result of the eruption, the cloud then becomes a type of feature seen elsewhere on Jupiter known as 'spaghetti bowls'.As Voyager 2 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 8 images taken once every Jupiter rotation period (about 10 hours). These images were acquired in the Violet filter around May 6, 1979. The spacecraft was about 50 million kilometers from Jupiter at that time.This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  2. Voyager 1 Red Spot Movie

    Science.gov (United States)

    2000-01-01

    This movie shows the portion of Jupiter around the Great Red Spot as it swirls through more than 60 Jupiter days. Notice the difference in speed and direction of the various zones of the atmosphere. The interaction of the atmospheric clouds and storm shows how dynamic the Jovian atmosphere is.As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 66 images taken once every Jupiter rotation period (about 10 hours). This time-lapse movie uses images taken every time Jupiter longitude 68W passed under the spacecraft. These images were acquired in the Blue filter from Jan. 6 to Feb. 3 1979. The spacecraft flew from 58 million kilometers to 31 million kilometers from Jupiter during that time.This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  3. Probing Theories of Gravity with Phase Space-Inferred Potentials of Galaxy Clusters

    CERN Document Server

    Stark, Alejo; Kern, Nicholas; Gifford, Daniel; Zhao, Gong-Bo; Li, Baojiu; Koyama, Kazuya; Nichol, Robert C

    2016-01-01

    Modified theories of gravity provide us with a unique opportunity to generate innovative tests of gravity. In Chameleon f(R) gravity, the gravitational potential differs from the weak-field limit of general relativity (GR) in a mass dependent way. We develop a probe of gravity which compares high mass clusters, where Chameleon effects are weak, to low mass clusters, where the effects can be strong. We utilize the escape velocity edges in the radius/velocity phase space to infer the gravitational potential profiles on scales of 0.3-1 virial radii. We show that the escape edges of low mass clusters are enhanced compared to GR, where the magnitude of the difference depends on the background field value |fR0|. We validate our probe using N-body simulations and simulated light cone galaxy data. For a DESI (Dark Energy Spectroscopic Instrument) Bright Galaxy Sample, including observational systematics, projection effects, and cosmic variance, our test can differentiate between GR and Chameleon f(R) gravity models, ...

  4. Voyages Through Time: Everything Evolves

    Science.gov (United States)

    Pendleton, Y. J.; Tarter, J. C.; DeVore, E. K.; O'Sullivan, K. A.; Taylor, S. M.

    2001-12-01

    Evolutionary change is a powerful framework for studying our world and our place therein. It is a recurring theme in every realm of science: over time, the universe, the planet Earth, life, and human technologies all change, albeit on vastly different scales. Evolution offers scientific explanations for the age-old question, "Where did we come from?" In addition, historical perspectives of science show how our understanding has evolved over time. The complexities of all of these systems will never reveal a "finished" story. But it is a story of epic size, capable of inspiring awe and of expanding our sense of time and place, and eminently worthy of investigating. This story is the basis of Voyages Through Time. Voyages Through Time (VTT), provides teachers with not only background science content and pedagogy, but also with materials and resources for the teaching of evolution. The six modules, Cosmic Evolution, Planetary Evolution, Origin of Life, Evolution of Life, Hominid Evolution, and Evolution of Technology, emphasize student inquiry, and promote the nature of science, as recommended in the NSES and BSL. The modules are unified by the overarching theme of evolution and the meta questions: "What is changing?" "What is the rate of change?" and "What is the mechanism of change?" Determination of student outcomes for the project required effective collaboration of scientists, teachers, students and media specialists. The broadest curricula students outcomes are 1) an enjoyment of science, 2) an understanding of the nature of science, especially the understanding of evidence and re-evaluation, and 3) key science content. The curriculum is being developed by the SETI Institute, NASA Ames Research Center, California Academy of Sciences, and San Francisco State University, and is funded by the NSF (IMD 9730693), with support form Hewlett-Packard Company, The Foundation for Microbiology, Combined Federated Charities, NASA Astrobiology Institute, and NASA Fundamental

  5. Probing the noncommutative structure of space with a quantum harmonic oscillator driven by gravitational wave

    CERN Document Server

    Saha, Anirban

    2015-01-01

    We investigate the quantum mechanical transitions, induced by the combined effect of Gravitational wave (GW) and noncommutative (NC) structure of space, among the states of a 2-dimensional harmonic oscillator. The phonon modes excited by the passing GW within the resonant bar-detector are formally identical to forced harmonic oscillator and they represent a length variation of roughly the same order of magnitude as the characteristic length-scale of spatial noncommutativity estimated from the phenomenological upper bound of the NC parameter. This motivates our present work. We employ a number of different GW wave-forms that are typically expected from possible astronomical sources. We find that the transition probablities are quite sensitive to the nature of polarization of the GW. We further elaborate on the particular type of sources of GW radiation which can induce transitions that can be used as effective probe of the spatial noncommutative structure.

  6. Very High Specific Energy, Medium Power Li/CFx Primary Battery for Launchers and Space Probes

    Science.gov (United States)

    Brochard, Paul; Godillot, Gerome; Peres, Jean Paul; Corbin, Julien; Espinosa, Amaya

    2014-08-01

    Benchmark with existing technologies shows the advantages of the lithium-fluorinated carbon (Li/CFx) technology for use aboard future launchers in terms of a low Total Cost of Ownership (TCO), especially for high energy demanding missions such as re-ignitable upper stages for long GTO+ missions and probes for deep space exploration.This paper presents the new results obtained on this chemistry in terms of electrical and climatic performances, abuse tests and life tests. Studies - co-financed between CNES and Saft - looked at a pure CFx version with a specific energy up to 500 Wh/kg along with a medium power of 80 to 100 W/kg.

  7. Probing the accelerating Universe with redshift-space distortions in VIPERS

    Science.gov (United States)

    de la Torre, Sylvain

    2016-10-01

    We present the first measurement of the growth rate of structure at z=0.8. It has been obtained from the redshift-space distortions observed in the galaxy clustering pattern in the VIMOS Public Redshift survey (VIPERS) first data release. VIPERS is a large galaxy redshift survey probing the large-scale structure at 0.5 Universe, which has been poorly explored until now. We obtain σ8 = 0.47 +/- 0.08 at z = 0.8 that is consistent with the predictions of standard cosmological models based on Einstein gravity. This measurement alone is however not accurate enough to allow the detection of possible deviations from standard gravity.

  8. Probing the Nodal Structure of Landau Level Wave Functions in Real Space.

    Science.gov (United States)

    Bindel, J R; Ulrich, J; Liebmann, M; Morgenstern, M

    2017-01-06

    The inversion layer of p-InSb(110) obtained by Cs adsorption of 1.8% of a monolayer is used to probe the Landau level wave functions within smooth potential valleys by scanning tunneling spectroscopy at 14 T. The nodal structure becomes apparent as a double peak structure of each spin polarized first Landau level, while the zeroth Landau level exhibits a single peak per spin level only. The real space data show single rings of the valley-confined drift states for the zeroth Landau level and double rings for the first Landau level. The result is reproduced by a recursive Green function algorithm using the potential landscape obtained experimentally. We show that the result is generic by comparing the local density of states from the Green function algorithm with results from a well-controlled analytic model based on the guiding center approach.

  9. Light as a probe of the structure of space-time

    Science.gov (United States)

    Tartaglia, Angelo

    2016-05-01

    Light is an intrinsically relativistic probe and when used in an adequately sized array of ring lasers it is sensible to the curvature and to the chirality of space-time. On this basis the GINGER experiment is being implemented at the underground National Laboratories at Gran Sasso. The experiment, whose objective is the measurement of the terrestrial frame dragging effect or deviations from it, will be presented and discussed in its foundation. Furthermore, at a bigger scale, the possibilities given by the under way GAIA mission and the proposed AGP, will be analyzed with a special attention paied to the possibility of extracting information concerning the angular momenta of the sun and the main bodies of the solar system.

  10. Voyager Ultraviolet Spectrometers calibration and the heliosphere neutrals composition: reassessment

    CERN Document Server

    Ben-Jaffel, Lotfi

    2016-01-01

    The Voyagers (V) 1 and 2 Ultraviolet Spectrometers (UVS) data harvest covers outer planets encounters, heliosphere sky-background measurements, and stellar spectrophotometry. Because their operation period overlaps with many ultraviolet missions, the V1 and V2 UVS calibration with other spectrometers are invaluable. Here we revisit the UVS calibration to assess the intriguing 243 % (V1) and 156 % (V2) sensitivity enhancements recently proposed. Using the Saturn Lyman-$\\alpha$ airglow, observed in-situ by both Voyagers, and remotely by IUE, we match the Voyager values to IUE, taking into account the shape of the Saturn Lyman-$\\alpha$ line observed with the Goddard High Resolution Spectrograph onboard the Hubble Space Telescope. For all known ranges of the interplanetary hydrogen density, we show that the V1 and V2 UVS sensitivities cannot be enhanced by the amounts thus far proposed. The same diagnostic holds for distinct channels covering the diffuse HeI 58.4 nm emission. Our prescription is to keep the origi...

  11. Comparison of Galileo Probe and Earth-Based Translation Rates of Jupiter's Equatorial Clouds

    Science.gov (United States)

    Beebe; Simon; Huber

    1996-05-10

    The Doppler wind speeds derived from Galileo probe data are comparable with the maximum translation speeds observed in the equatorial zone by Voyager 1 and the Hubble Space Telescope. Slower published values of east-west winds are based on measurements of larger features and should be interpreted as translation rates of large weather systems interacting with the wind. The nature of the hot-spot region that the Galileo probe entered is compatible with a high-speed jet at 6 degrees north. The hot spot is associated with an equatorial weather system that spans 5 degrees of latitude and translates at 103 meters per second.

  12. Application of high stability oscillators to radio science experiments using deep space probes

    Science.gov (United States)

    Kursinski, Emil R.

    1990-01-01

    The microwave telecommunication links between the earth and deep space probes have long been used to conduct radio science experiments which take advantage of the phase coherency and stability of these links. These experiments measure changes in the phase delay of the signals to infer electrical, magnetic and gravitational properties of the solar system environment and beyond through which the spacecraft and radio signals pass. The precision oscillators, from which the phase of the microwave signals are derived, play a key role in the stability of these links and therefore the sensitivity of these measurements. These experiments have become a driving force behind recent and future improvements in the Deep Space Network and spacecraft oscillators and frequency and time distribution systems. Three such experiments which are key to these improvements are briefly discussed and relationship between their sensitivity and the signal phase stability is described. The first is the remote sensing of planetary atmospheres by occultation in which the radio signal passes through the atmosphere and is refracted causing the signal pathlength to change from which the pressure and the temperature of the atmosphere can be derived. The second experiment is determination of the opacity of planetary rings by passage of the radio signals through the rings. The third experiment is the research for very low frequency gravitational radiation. The fractional frequency variation of the signal is comparable to the spatial strain amplitude the system is capable of detecting. A summary of past results and future possibilities for these experiments are presented.

  13. Application of high stability oscillators to radio science experiments using deep space probes

    Science.gov (United States)

    Kursinski, Emil R.

    1990-01-01

    The microwave telecommunication links between the earth and deep space probes have long been used to conduct radio science experiments which take advantage of the phase coherency and stability of these links. These experiments measure changes in the phase delay of the signals to infer electrical, magnetic and gravitational properties of the solar system environment and beyond through which the spacecraft and radio signals pass. The precision oscillators, from which the phase of the microwave signals are derived, play a key role in the stability of these links and therefore the sensitivity of these measurements. These experiments have become a driving force behind recent and future improvements in the Deep Space Network and spacecraft oscillators and frequency and time distribution systems. Three such experiments which are key to these improvements are briefly discussed and relationship between their sensitivity and the signal phase stability is described. The first is the remote sensing of planetary atmospheres by occultation in which the radio signal passes through the atmosphere and is refracted causing the signal pathlength to change from which the pressure and the temperature of the atmosphere can be derived. The second experiment is determination of the opacity of planetary rings by passage of the radio signals through the rings. The third experiment is the research for very low frequency gravitational radiation. The fractional frequency variation of the signal is comparable to the spatial strain amplitude the system is capable of detecting. A summary of past results and future possibilities for these experiments are presented.

  14. Voyages Through Time: Everything Evolves

    Science.gov (United States)

    Fisher, Jane; Tarter, Jill; Devore, Edna; Pendleton, Yvonne; O'Sullivan, Kathleen; Burke, Meg

    2004-06-01

    The SETI Institute, the California Academy of Sciences, NASA Ames Research Center, and San Francisco State University have developed standards-based curriculum materials for a one-year high school integrated science course centered on the unifying theme of evolution. Scientists, teachers, curriculum writers, and media specialists are currently finalizing six modules that integrate astronomical, geological, and biological sciences as well as the history of science and technology. The sequence of lessons in each module is designed to promote students' understanding and skills as defined by the National Science Education Standards and Benchmarks for Science Literacy. The modules cover: Cosmic Evolution, Planetary Evolution, Origin of Life, Evolution of Life, Hominid Evolution, and the Evolution of Technology. The core lessons for all six modules are provided via CD-ROM, including instructional guidelines, science background information, and additional resources (print, audiovisual, software, WWW sites, and databases). These products will be published as a complete set for use as a yearlong science course and will also be available as individual modules for use in discipline-based courses. Evolutionary change is a powerful framework for studying our world and our place therein. It is a story of epic size, capable of inspiring awe and of expanding our sense of time and place. This story is the basis of Voyages Through Time.

  15. Magnetically insulated baffled probe for real-time monitoring of equilibrium and fluctuating values of space potentials, electron and ion temperatures, and densities.

    Science.gov (United States)

    Demidov, V I; Koepke, M E; Raitses, Y

    2010-10-01

    By restricting the electron-collection area of a cold Langmuir probe compared to the ion-collection area, the probe floating potential can become equal to the space potential, and thus conveniently monitored, rather than to a value shifted from the space potential by an electron-temperature-dependent offset, i.e., the case with an equal-collection-area probe. This design goal is achieved by combining an ambient magnetic field in the plasma with baffles, or shields, on the probe, resulting in species-selective magnetic insulation of the probe collection area. This permits the elimination of electron current to the probe by further adjustment of magnetic insulation which results in an ion-temperature-dependent offset when the probe is electrically floating. Subtracting the floating potential of two magnetically insulated baffled probes, each with a different degree of magnetic insulation, enables the electron or ion temperature to be measured in real time.

  16. Acceleration and transport of anomalous cosmic rays: Investigating the spectral evolution at Voyager 1 beyond the termination shock

    Science.gov (United States)

    Senanayake, Udara K.

    Interstellar neutral atoms entering the heliosphere could become ionized by photo-ionization or charge exchange with solar-wind ions. These newly created ions are picked up by the solar wind and carried to the termination shock (TS) where they are believed to be accelerated by the diffusive shock acceleration process to high energies (˜1-100 MeV n-1). The accelerated ions are known as anomalous cosmic rays (ACRs). When NASA's space probe, Voyager 1 crossed the TS in 2004, the measured ACR spectra did not match the theoretical prediction of a continuous power law, and the source of the high-energy ACRs was not observed. However, over the next few years, in the declining phase of the solar cycle, the spectra began to evolve into the expected power-law profile. The model developed here is based on the suggestion that ACRs are still accelerated at the shock, but away from the Voyager crossing points. First, we study ACR acceleration using a three-dimensional, non-spherical model of the heliosphere that is axisymmetric with respect to the interstellar flow direction. A semi-analytic model of the plasma and magnetic field backgrounds is developed to permit an investigation over a wide range of parameters under controlled conditions. The model is applied to helium ACRs, whose phase-space trajectories are stochastically integrated backward in time until a pre-specified, low-energy boundary of 0.5 MeV n-1, is reached. Next, we propose that the solar cycle had an important effect on the evolving of the spectra in the heliosheath. To investigate this, a magnetohydrodynamic background model with stationary solar-wind inner boundary conditions was used to model the transport of helium and oxygen ions. In addition, we developed a charge consistent stochastic model to simulate multiply charged oxygen ACRs. It is shown that the spectral evolution of ACRs in the heliosheath at Voyager 1 could be explained by combining intermediate-energy particles arriving from the heliotail

  17. Enhancing Resilience in Youth through a 10-Day Developmental Voyage

    Science.gov (United States)

    Hayhurst, Jill; Hunter, John A.; Kafka, Sarah; Boyes, Mike

    2015-01-01

    The present study sought to examine the potential for resilience to be enhanced in a group of youth participating in a developmental voyage, and to identify the factors that contribute to increased resilience following the voyage. Two studies are reported. Study 1 revealed that voyage participants experienced increased resilience over the course…

  18. Enhancing Resilience in Youth through a 10-Day Developmental Voyage

    Science.gov (United States)

    Hayhurst, Jill; Hunter, John A.; Kafka, Sarah; Boyes, Mike

    2015-01-01

    The present study sought to examine the potential for resilience to be enhanced in a group of youth participating in a developmental voyage, and to identify the factors that contribute to increased resilience following the voyage. Two studies are reported. Study 1 revealed that voyage participants experienced increased resilience over the course…

  19. Voyager Reading Programs. What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2010

    2010-01-01

    "Voyager Passport"[TM] is a supplemental reading intervention system for students in grades K-5. "Voyager Passport Reading Journeys"[TM] is a reading intervention program designed for adolescents who struggle with reading. The "Voyager Universal Literacy System"[R] is a K-3 reading program that includes a core reading…

  20. The space adventure comes to a conference at CERN

    CERN Document Server

    CERN Bulletin

    2012-01-01

    From 5 to 7 November, CERN will host the 4th International Conference on Particle and Fundamental Physics in Space (SpacePart12). Special talks open to the general public will be given by two of the biggest names in space exploration: Edward Stone, project scientist for the Voyager probes, and William Gerstenmaier, former Manager of the International Space Station (ISS) programme.     Launched at Isola d’Elba (Italy) in 2002, then continued in Washington D.C. (USA) in 2003 and Beijing (China) in 2006, the SpacePart conferences are an opportunity for researchers and space policy makers from across the world to exchange opinions on the developments of space-related science and technology programmes. This year, SpacePart coincides with the centenary of the discovery of cosmic rays and will be held at CERN. On 5 November, Edward Stone, professor at the California Institute of Technology and project scientist for the Voyager probes since 1972, will give a talk on the extraordin...

  1. Mobile Probing and Probes

    DEFF Research Database (Denmark)

    2013-01-01

    Mobile probing is a method, developed for learning about digital work situations, as an approach to discover new grounds. The method can be used when there is a need to know more about users and their work with certain tasks, but where users at the same time are distributed (in time and space......). Mobile probing was inspired by the cultural probe method, and was influenced by qualitative interview and inquiry approaches. The method has been used in two subsequent projects, involving school children (young adults at 15-17 years old) and employees (adults) in a consultancy company. Findings point...... to mobile probing being a flexible method for uncovering the unknowns, as a way of getting rich data to the analysis and design phases. On the other hand it is difficult to engage users to give in depth explanations, which seem easier in synchronous dialogs (whether online or face2face). The development...

  2. Mobile Probing and Probes

    DEFF Research Database (Denmark)

    2012-01-01

    Mobile probing is a method, which has been developed for learning about digital work situations, as an approach to discover new grounds. The method can be used when there is a need to know more about users and their work with certain tasks, but where users at the same time are distributed (in time...... and space). Mobile probing was inspired by the cultural probe method, and was influenced by qualitative interview and inquiry approaches. The method has been used in two subsequent projects, involving school children (young adults at 15-17 years old) and employees (adults) in a consultancy company. Findings...... point to mobile probing being a flexible method for uncovering the unknowns, as a way of getting rich data to the analysis and design phases. On the other hand it is difficult to engage users to give in depth explanations, which seem easier in synchronous dialogs (whether online or face2face...

  3. Mobile Probing and Probes

    DEFF Research Database (Denmark)

    2012-01-01

    Mobile probing is a method, which has been developed for learning about digital work situations, as an approach to discover new grounds. The method can be used when there is a need to know more about users and their work with certain tasks, but where users at the same time are distributed (in time...... and space). Mobile probing was inspired by the cultural probe method, and was influenced by qualitative interview and inquiry approaches. The method has been used in two subsequent projects, involving school children (young adults at 15-17 years old) and employees (adults) in a consultancy company. Findings...... point to mobile probing being a flexible method for uncovering the unknowns, as a way of getting rich data to the analysis and design phases. On the other hand it is difficult to engage users to give in depth explanations, which seem easier in synchronous dialogs (whether online or face2face...

  4. Is a linear probe helpful in diagnosing diseases of pulmonary interstitial spaces?

    Directory of Open Access Journals (Sweden)

    Natalia Buda

    2017-06-01

    Full Text Available In a lung ultrasound examination, interstitial lung lesions are visible as numerous B-line artifacts, and are best recorded with the use of a convex probe. Interstitial lung lesions may result from many conditions, including cardiogenic pulmonary oedema, non-cardiogenic pulmonary oedema, or interstitial lung disease. Hence difficulties in the differential diagnostics of the above clinical conditions. This article presents cases of patients suffering from interstitial lung lesions discovered in the course of lung ultrasound examination. The patients were examined with a 3.5–5.0 MHz convex probe and a 7.0–11.0 MHz linear probe. Ultrasound images have been analysed, and differences in the imaging with both probes in patients with interstitial lung lesions have been detailed. The use of a linear probe in patients with interstitial lung lesions (discovered with a convex or a micro-convex probe provides additional information on the source of the origin of the lesions.

  5. Space and time-resolved probing of heterogeneous catalysis reactions using lab-on-a-chip

    Science.gov (United States)

    Navin, Chelliah V.; Krishna, Katla Sai; Theegala, Chandra S.; Kumar, Challa S. S. R.

    2016-03-01

    Probing catalytic reactions on a catalyst surface in real time is a major challenge. Herein, we demonstrate the utility of a continuous flow millifluidic chip reactor coated with a nanostructured gold catalyst as an effective platform for in situ investigation of the kinetics of catalytic reactions by taking 5-(hydroxymethyl)furfural (HMF) to 2,5-furandicarboxylic acid (FDCA) conversion as a model reaction. The idea conceptualized in this paper can not only dramatically change the ability to probe the time-resolved kinetics of heterogeneous catalysis reactions but also used for investigating other chemical and biological catalytic processes, thereby making this a broad platform for probing reactions as they occur within continuous flow reactors.Probing catalytic reactions on a catalyst surface in real time is a major challenge. Herein, we demonstrate the utility of a continuous flow millifluidic chip reactor coated with a nanostructured gold catalyst as an effective platform for in situ investigation of the kinetics of catalytic reactions by taking 5-(hydroxymethyl)furfural (HMF) to 2,5-furandicarboxylic acid (FDCA) conversion as a model reaction. The idea conceptualized in this paper can not only dramatically change the ability to probe the time-resolved kinetics of heterogeneous catalysis reactions but also used for investigating other chemical and biological catalytic processes, thereby making this a broad platform for probing reactions as they occur within continuous flow reactors. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06752a

  6. Estimating space-time parameters with a quantum probe in a lossy environment

    CERN Document Server

    Kish, Sebastian P

    2016-01-01

    We study the problem of estimating the Schwarzschild radius of a massive body using Gaussian quantum probe states. Previous calculations assumed that the probe state remained pure after propagating a large distance. In a realistic scenario, there would be inevitable losses. Here we introduce a practical approach to calculate the Quantum Fisher Informations (QFIs) for a quantum probe that has passed through a lossy channel. Whilst for many situations loss means coherent states are optimal, we identify certain situations for which squeezed states have an advantage. We also study the effect of the frequency profile of the wavepacket propagating from Alice to Bob. There exists an optimal operating point for a chosen mode profile. In particular, employing a smooth rectangular frequency profile significantly improves the error bound on the Schwarzschild radius compared to a Gaussian frequency profile.

  7. On the accuracy of the relativistic parameters beta, gamma, and the solar oblateness coefficient J2, as deduced from ranging data of a drag-free space probe

    Science.gov (United States)

    Roth, E. A.

    1971-01-01

    Motion in the general gravity field is described mathematically. A covariance analysis, based on two simple models, is presented. Two drag-free space probes were considered, for which the orbital elements are given.

  8. Investigating Global Ion and Neutral Atom Populations with IBEX and Voyager

    Science.gov (United States)

    Florinski, Vladimir

    2016-01-01

    The main objective of this project was to investigate pickup ion (PUI) production in the solar wind and heliosheath (the region between the termination shock and the heliopause) and compute the distributed energetic neutral atom fluxes throughout the helioshpere. The simulations were constrained by comparing the model output against observations from Ulysses, New Horizons, Voyager 1 and 2, and IBEX space probes. As evidenced by the number of peer reviewed journal publications resulting from the project (13 plus three submitted) and their citation rate (156 citations over three years), the project has made a lasting contribution to the field. The outcome is a significant improvement of our understanding of the pickup ion production and distribution in the distant heliosphere. The team has accomplished the entire set of tasks A-H set forth in the proposal. Namely, the transport modeling framework has been augmented with two populations of pickup ions (PUIs), the boundary conditions for the plasma and interstellar neutral hydrogen were verified against Ulysses and New Horizons PUI and an optimal set of velocity diffusion parameters established. The multi-component fluxes of PUIs were computed and isotropic velocity distributions generated for each cell in the computer simulation that covered the heliosphere from 1.5 AU to the heliopause. The distributions were carefully compared with in situ measurements at 3 AU (Ulysses), 12 AU (New Horizons), and 80-90 AU (Voyager 1 and 2) as well as those inferred from ENA fluxes measured by Cassini and IBEX (Wu et al., 2016). Some examples of modeldata comparison are shown in Figure 1. We have used coupled MHD-plasma and kinetic-neutral code to investigate the likely range of plasma and magnetic field parameters in the local interstellar medium (LISM), based on the assumption that the shape of the IBEX ribbon could be used to determine the orientation of the interstellar magnetic field. While the magnetic field is believed to be

  9. On whether or not voyager 1 has crossed the heliopause

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, L. A.; Gloeckler, G., E-mail: lafisk@umich.edu [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143 (United States)

    2014-07-01

    The Voyager 1 spacecraft is currently in the vicinity of the heliopause, which separates the heliosphere from the local interstellar medium. There has been a precipitous decrease in particles accelerated in the heliosphere, and a substantial increase in galactic cosmic rays (GCRs), suggesting easy escape of the former across the heliopause, and entry of the latter. The question is, has Voyager 1 actually crossed the heliopause and is it now in the interstellar medium? We contend that the evidence is inconclusive. The direction of the magnetic field observed by Voyager 1 is unchanged from the direction of the heliospheric magnetic field, and different from the expected direction of the interstellar magnetic field. However, the plasma density, which is measured from observations of plasma waves, is similar to the expected interstellar density and much larger than the solar wind plasma density observed by Voyager 2 (which has a working plasma detector) at smaller heliocentric distances than Voyager 1. In this paper, an analytic model is presented that is based upon and is consistent with all Voyager observations, and in which the higher plasma densities measured by Voyager 1 are due simply to compressed solar wind. Thus both the magnetic field and the plasma density observations are consistent with Voyager 1 still remaining well within the heliosheath. The model has a simple test: Voyager 1 should encounter a magnetic sector boundary crossing, where the behavior of particles accelerated in the heliosphere and the GCRs will be different from what Voyager 1 is now observing.

  10. Voyager 2 solar plasma and magnetic field spectral analysis for intermediate data sparsity

    CERN Document Server

    Gallana, Luca; Iovieno, Michele; Fosson, Sophie M; Magli, Enrico; Opher, Merav; Richardson, John D; Tordella, Daniela

    2015-01-01

    The Voyager probes are the furthest, still active, spacecraft ever launched from Earth. During their 38-year trip, they have collected data regarding solar wind properties (such as the plasma velocity and magnetic field intensity). Unfortunately, a complete time evolution of the measured physical quantities is not available. The time series contains many gaps which increase in frequency and duration at larger distances. The aim of this work is to perform a spectral and statistical analysis of the solar wind plasma velocity and magnetic field using Voyager 2 data measured in 1979, when the gaps/signal ratio is of order of unity. This analysis is achieved using four different data reconstruction techniques: averages on linearly interpolated subsets, correlation of linearly interpolated data, compressed sensing spectral estimation, and maximum likelihood data reconstruction. With five frequency decades, the spectra we obtained have the largest frequency range ever computed at 5 astronomical units from the Sun; s...

  11. Analysis of Clumps in Saturn's F Ring from Voyager and Cassini

    CERN Document Server

    French, Robert S; Showalter, Mark R; Antonsen, Adrienne K; Packard, Douglas R

    2014-01-01

    Saturn's F ring is subject to dynamic structural changes over short periods. Among the observed phenomena are diffuse extended bright clumps (ECs) ~ 3-40 degrees in longitudinal extent. These ECs appear, evolve, and disappear over a span of days to months. ECs have been seen by the two Voyager spacecraft, the Cassini orbiter, and various ground- and space-based telescopes. Showalter (2004, Icarus, 171, 356-371) analyzed all Voyager images of the F ring and found that there were 2-3 major and 20-40 minor ECs present in the ring at any given time. We expand upon these results by comparing the ECs seen by Voyager to those seen by Cassini in 2004-2010. We find that the number of minor ECs has stayed roughly constant and the ECs have similar distributions of angular width, absolute brightness, and semimajor axis. However, the common exceptionally bright ECs seen by Voyager are now exceedingly rare, with only two instances seen by Cassini in the six years, and they are now also much dimmer relative to the mean ring...

  12. New local interstellar spectra for protons, helium and carbon derived from PAMELA and Voyager 1 observations

    Science.gov (United States)

    Bisschoff, D.; Potgieter, M. S.

    2016-02-01

    With the cosmic ray observations made by the Voyager 1 spacecraft outside the dominant modulating influence of the heliosphere, the comparison of computed galactic spectra with experimental data at lower energies is finally possible. Spectra for specifically protons, helium and carbon nuclei, computed by galactic propagation models, can now be compared with observations at low energies from Voyager 1 and at high energies from the PAMELA space detector at Earth. We set out to reproduce the Voyager 1 observations in the energy range of 6 MeV/nuc to 60 MeV/nuc, and the PAMELA spectrum above 50 GeV/nuc, using the GALPROP code, similarly to our previous study for Voyager 1 electrons. By varying the galactic diffusion parameters in the GALPROP plain diffusion model, specifically the rigidity dependence of spatial diffusion, and then including reacceleration, we compute spectra simultaneously for galactic protons, helium and carbon. We present new local interstellar spectra, with expressions for the energy range of 3 MeV/nuc to 100 GeV/nuc, which should be of value for solar modulation modeling.

  13. New local interstellar spectra for protons, Helium and Carbon derived from PAMELA and Voyager 1 observations

    CERN Document Server

    Bisschoff, Driaan

    2015-01-01

    With the cosmic ray observations made by the Voyager 1 spacecraft outside the dominant modulating influence of the heliosphere, the comparison of computed galactic spectra with experimental data at lower energies is finally possible. Spectra for specifically protons, Helium and Carbon nuclei, computed by galactic propagation models, can now be compared with observations at low energies from Voyager 1 and at high energies from the PAMELA space detector at Earth. We set out to reproduce the Voyager 1 observations in the energy range of 6 MeV/nuc to 60 MeV/nuc, and the PAMELA spectrum above 50 GeV/nuc, using the GALPROP code, similarly to our previous study for Voyager 1 electrons. By varying the galactic diffusion parameters in the GALPROP plain diffusion model, specifically the rigidity dependence of spatial diffusion, and then including reacceleration, we compute spectra simultaneously for galactic protons, Helium and Carbon.We present new local interstellar spectra, with expressions for the energy range of 3...

  14. Fiber-Optic Imaging Probe Developed for Space Used to Detect Diabetes Through the Eye

    Science.gov (United States)

    Ansari, Rafat R.; Chenault, Michelle V.; Datiles, Manuel B., III; Sebag, J.; Suh, Kwang I.

    2000-01-01

    Approximately 16 million Americans have diabetes mellitus, which can severely impair eyesight by causing cataracts, diabetic retinopathy, and glaucoma. Cataracts are 1.6 times more common in people with diabetes than in those without diabetes, and cataract extraction is the only surgical treatment. In many cases, diabetes-related ocular pathologies go undiagnosed until visual function is compromised. This ongoing pilot project seeks to study the progression of diabetes in a unique animal model by monitoring changes in the lens with a safe, sensitive, dynamic light-scattering probe. Dynamic light scattering (DLS), has the potential to diagnose cataracts at the molecular level. Recently, a new DLS fiber-optic probe was developed at the NASA Glenn Research Center at Lewis Field for noncontact, accurate, and extremely sensitive particle-sizing measurements in fluid dispersions and suspensions (ref. 1). This compact, portable, and rugged probe is free of optical alignment, offers point-and-shoot operation for various online field applications and challenging environments, and yet is extremely flexible in regards to sample container sizes, materials, and shapes. No external vibration isolation and no index matching are required. It can measure particles as small as 1 nm and as large as few micrometers in a wide concentration range from very dilute (waterlike) dispersions to very turbid (milklike) suspensions. It is safe and fast to use, since it only requires very low laser power (10 nW to 3 mW) with very short data acquisition times (2 to 10 sec).

  15. The Use of Langmuir Probes in Non-Maxwellian Space Plasmas

    Science.gov (United States)

    Hoegy, Walter R.; Brace, Larry H.

    1998-01-01

    Disturbance of the Maxwellian plasma may occur in the vicinity of a spacecraft due to photoemission, interactions between the spacecraft and thermospheric gases, or electron emissions from other devices on the spacecraft. Significant non-maxwellian plasma distributions may also occur in nature as a mixture of ionospheric and magnetospheric plasmas or secondaries produced by photoionization in the thermosphere or auroral precipitation. The general formulas for current collection (volt-ampere curves) by planar, cylindrical, and spherical Langmuir probes in isotropic and anisotropic non-maxwellian plasmas are examined. Examples are given of how one may identify and remove the non-maxwellian components in the Langmuir probe current to permit the ionospheric parameters to be determined. Theoretical volt-ampere curves presented for typical examples of non-maxwellian distributions include: two-temperature plasmas and a thermal plasma with an energetic electron beam. If the non-ionospheric electrons are Maxwellian at a temperature distinct from that of the ionosphere electrons, the volt-ampere curves can be fitted directly to obtain the temperatures and densities of both electron components without resorting to differenting the current. For an arbitrary isotropic distribution, the current for retarded particles is shown to be identical for the three geometries. For anisotropic distributions, the three probe geometries are not equally suited for measuring the ionospheric electron temperature and density or for determining the distribution function in the presence of non-maxwellian back-round electrons.

  16. Ultrahigh-energy photons as probes of Lorentz symmetry violations in stringy space-time foam models.

    Science.gov (United States)

    Maccione, Luca; Liberati, Stefano; Sigl, Günter

    2010-07-09

    The time delays between γ rays of different energies from extragalactic sources have often been used to probe quantum gravity models in which Lorentz symmetry is violated. It has been claimed that these time delays can be explained by or at least put the strongest available constraints on quantum gravity scenarios that cannot be cast within an effective field theory framework, such as the space-time foam, D-brane model. Here we show that this model would predict too many photons in the ultrahigh energy cosmic ray flux to be consistent with observations. The resulting constraints on the space-time foam model are much stronger than limits from time delays and allow for Lorentz violation effects way too small for explaining the observed time delays.

  17. The atmospheric circulation of a nine-hot Jupiter sample: Probing circulation and chemistry over a wide phase space

    CERN Document Server

    Kataria, Tiffany; Lewis, Nikole K; Visscher, Channon; Showman, Adam P; Fortney, Jonathan J; Marley, Mark S

    2016-01-01

    We present results from an atmospheric circulation study of nine hot Jupiters that comprise a large transmission spectral survey using the Hubble and Spitzer Space Telescopes. These observations exhibit a range of spectral behavior over optical and infrared wavelengths which suggest diverse cloud and haze properties in their atmospheres. By utilizing the specific system parameters for each planet, we naturally probe a wide phase space in planet radius, gravity, orbital period, and equilibrium temperature. First, we show that our model "grid" recovers trends shown in traditional parametric studies of hot Jupiters, particularly equatorial superrotation and increased day-night temperature contrast with increasing equilibrium temperature. We show how spatial temperature variations, particularly between the dayside and nightside and west and east terminators, can vary by hundreds of K, which could imply large variations in Na, K, CO and CH4 abundances in those regions. These chemical variations can be large enough...

  18. Ultra high energy photons as probes of Lorentz symmetry violations in stringy space-time foam models

    Energy Technology Data Exchange (ETDEWEB)

    Maccione, Luca [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Liberati, Stefano [SISSA, Trieste (Italy); INFN, Trieste (Italy); Sigl, Guenter [Hamburg Univ. (Germany). Inst. fuer Theoretische Physik

    2010-03-15

    The time delays between gamma-rays of different energies from extragalactic sources have often been used to probe quantum gravity models in which Lorentz symmetry is violated. It has been claimed that these time delays can be explained by or at least put the strongest available constraints on quantum gravity scenarios that cannot be cast within an effective field theory framework, such as the space-time foam, D-brane model. Here we show that this model would predict too many photons in the ultra-high energy cosmic ray flux to be consistent with observations. The resulting constraints on the space-time foam model are much stronger than limits from time delays and allow for Lorentz violations effects way too small for explaining the observed time delays. (orig.)

  19. In vitro cultured cells as probes for space radiation effects on biological systems

    Energy Technology Data Exchange (ETDEWEB)

    Meli, A.; Perrella, G.; Curcio, F.; Ambesi-Impiombato, F.S. [Dipartimento di Patologia e Medicina Sperimentale e Clinica, Universita di Udine, P.le S. Maria della Misericordia, 33100 Udine (Italy)

    1999-12-06

    Near future scenarios of long-term and far-reaching manned space missions, require more extensive knowledge of all possible biological consequences of space radiation, particularly in humans, on both a long-term and a short-term basis. In vitro cultured cells have significantly contributed to the tremendous advancement of biomedical research. It is therefore to be expected that simple biological systems such as cultured cells, will contribute to space biomedical sciences. Space represents a novel environment, to which life has not been previously exposed. Both microgravity and space radiation are the two relevant components of such an environment, but biological adaptive mechanisms and efficient countermeasures can significantly minimize microgravity effects. On the other hand, it is felt that space radiation risks may be more relevant and that defensive strategies can only stem from our deeper knowledge of biological effects and of cellular repair mechanisms. Cultured cells may play a key role in such studies. Particularly, thyroid cells may be relevant because of the exquisite sensitivity of the thyroid gland to radiation. In addition, a clone of differentiated, normal thyroid follicular cells (FRTL5 cells) is available in culture, which is well characterized and particularly fit for space research.

  20. Probing phase-space noncommutativity through quantum mechanics and thermodynamics of free particles and quantum rotors

    CERN Document Server

    Bastos, Catarina; Santos, Jonas F G

    2014-01-01

    Novel quantization properties related to the state vectors and the energy spectrum of a two-dimensional system of free particles are obtained in the framework of noncommutative (NC) quantum mechanics (QM) supported by the Weyl-Wigner formalism. Besides reproducing the magnetic field aspect of the Zeeman effect, the momentum space NC parameter introduces mutual information properties quantified by the linear entropy related to the relevant Hilbert space coordinates. Supported by the QM in the phase-space, the thermodynamic limit is obtained, and the results are extended to three-dimensional systems. The noncommutativity imprints on the thermodynamic variables related to free particles are identified and, after introducing some suitable constraints to fix an axial symmetry, the analysis is extended to two- and- three dimensional quantum rotor systems, for which the quantization aspects and the deviation from standard QM results are verified.

  1. Probing the noncommutative effects of phase space in the time-dependent Aharonov-Bohm effect

    CERN Document Server

    Ma, Kai; Yang, Huan-Xiong

    2016-01-01

    We study the noncommutative corrections on the time-dependent Aharonov-Bohm effect when both the coordinate-coordinate and momentum-momentum noncommutativities are considered. This study is motivated by the recent observation that there is no net phase shift in the time-dependent AB effect on the ordinary space, and therefore tiny derivation from zero can indicate new physics. The vanishing of the time-dependent AB phase shift on the ordinary space is preserved by the gauge and Lorentz symmetries. However, on the noncomutative phase space, while the ordinary gauge symmetry can be kept by the Seiberg-Witten map, but the Lorentz symmetry is broken. Therefore nontrivial noncommutative corrections are expected. We find there are three kinds of noncommutative corrections in general: 1) $\\xi$-dependent correction which comes from the noncommutativity among momentum operators; 2) momentum-dependent correction which is rooted in the nonlocal interactions in the noncommutative extended model; 3) momentum-independent c...

  2. Photons with sub-Planckian Energy Cannot Efficiently Probe Space-Time Foam

    CERN Document Server

    Chen, Yanbei; Ma, Yiqiu

    2015-01-01

    Extra-galactic sources of photons have been used to constrain space-time quantum fluctuations in the Universe. In these proposals, the fundamental "fuzziness" of distance caused by space-time quantum fluctuations has been directly identified with fluctuations in optical paths. Phase-front corrugations deduced from these optical-path fluctuations are then applied to light from extra-galactic point sources, and used to constrain various models of quantum gravity. However, when a photon propagates in three spatial dimensions, it does not follow a specific ray, but rather samples a finite, three-dimensional region around that ray --- thereby averaging over space-time quantum fluctuations all through that region. We use a simple, random-walk type model to demonstrate that, once the appropriate wave optics is applied, the averaging of neighboring space-time fluctuations will cause much less distortion to the phase front. In our model, the extra suppression factor due to diffraction is the wave length in units of th...

  3. Space Software

    Science.gov (United States)

    1990-01-01

    Xontech, Inc.'s software package, XonVu, simulates the missions of Voyager 1 at Jupiter and Saturn, Voyager 2 at Jupiter, Saturn, Uranus and Neptune, and Giotto in close encounter with Comet Halley. With the program, the user can generate scenes of the planets, moons, stars or Halley's nucleus and tail as seen by Giotto, all graphically reproduced with high accuracy in wireframe representation. Program can be used on a wide range of computers, including PCs. User friendly and interactive, with many options, XonVu can be used by a space novice or a professional astronomer. With a companion user's manual, it sells for $79.

  4. Part Twelve: The Voyages of John Matthias

    OpenAIRE

    Printz-Påhlson, Göran

    2013-01-01

    In August 1974, when the Watergate scandal was moving into its last phase, the American poet John Matthias returned to his home, in South Bend, Indiana, after a year’s stay in England, traveling on the Polish ocean-liner Stefan Bathory. In June of 1976 he set out to sea again, this time on a Russian ship, the Mikhail Lermontov, in order to spend another year in England, as a Visiting Fellow in Poetry in Clare Hall, Cambridge. The voyages took approximately nine days each, and on both ships he...

  5. The Role Played by Space-based Probes in our Understanding of the Cosmos

    Science.gov (United States)

    Macchetto, Ferdinando Duccio

    Over the last fifteen years a growing fleet of modern space-based astronomical telescopes has changed drastically our view of the universe. Most of these accomplishments build upon the work of ground-based astronomers over many decades, or even centuries. The combination of telescopes observing the universe at many different wavelengths has converted many prior hypotheses, for which supporting empirical data were scant, ambiguous and painfully difficult to obtain, into clearly and decisively demonstrated truth. But space observatories have gone well beyond that. In particular the Hubble Space Telescope with its combination of sharp images and deep dynamic range, has provided a detailed view of the unimagined complexity and diversity of the universe, as well as its startling beauty. It has yielded numerous surprises and raised new fundamental questions on the basic structure and laws that govern the universe. To answer these questions will require the efforts of ground-based and new space-based observatories working in combined programs over many years. In my talk I will illustrate some of the key discoveries that these space-based observatories have made such as: the deep imaging the distant universe; the calibration of the distance scale and the determination of the age of the universe; the discovery of the acceleration of the expansion rate of the universe, which requires a "dark energy" or new physics to explain it; the detection and measurement of supermassive black holes and the solution to the long standing problem of the nature of Quasars; the solution to the problem of whether Gamma Ray sources originated in our galaxy or at cosmological distances; the renewed interest in the problem of the birth of Stars and the formation of Planetary Systems; the death of Stars and the formation of supernovae, black holes and neutron stars and last but not least the exciting studies of the planets and satellites in our own dynamic solar system

  6. Probing cosmology and gravity with redshift-space distortions around voids

    CERN Document Server

    Hamaus, Nico; Lavaux, Guilhem; Wandelt, Benjamin D

    2015-01-01

    Cosmic voids in the large-scale structure of the Universe affect the peculiar motions of objects in their vicinity. Although these motions are difficult to observe directly, the clustering pattern of their surrounding tracers in redshift space is influenced in a unique way. This allows to investigate the interplay between densities and velocities around voids, which is solely dictated by the laws of gravity. With the help of N-body simulations and derived mock-galaxy catalogs we calculate the average density fluctuations inside and outside voids identified with a watershed algorithm in redshift space and compare the results with the expectation from general relativity and the LCDM model of cosmology. We find that simple linear-theory predictions work remarkably well in describing the dynamics of voids even on relatively small scales. Adopting a Bayesian inference framework, we determine the full posterior probability distribution of our model parameters and forecast the achievable accuracy on measurements of ...

  7. Probing space charge and resolving overlimiting current mechanisms at the microchannel-nanochannel interface.

    Science.gov (United States)

    Schiffbauer, Jarrod; Liel, Uri; Leibowitz, Neta; Park, Sinwook; Yossifon, Gilad

    2015-07-01

    We present results demonstrating the space charge-mediated transition between classical, diffusion-limited current and surface-conduction dominant over-limiting current in a shallow microchannel-nanochannel device. The extended space charge layer develops at the depleted microchannel-nanochannel entrance at high current and is correlated with a distinctive maximum in the dc resistance. Experimental results for a shallow surface-conduction dominated system are compared with theoretical models, allowing estimates of the effective surface charge at high voltage to be obtained. In comparison to an equilibrium estimate of the surface charge obtained from electrochemical impedance spectroscopy, it is further observed that the effective surface charge appears to change under applied voltage.

  8. Active probing of space plasmas. Final report, 25 October 1985-30 September 1989

    Energy Technology Data Exchange (ETDEWEB)

    Chan, C.; Silevitch, M.B.; Villalon, E.

    1989-09-01

    During the course of the research period our efforts were focused on the following areas: (1) An examination of stochastic acceleration mechanisms in the ionosphere; (2) A study of nonequilibrium dynamics of the coupled magnetosphere - ionosphere system; and (3) Laboratory studies of active space experiments. Reprints include: Dynamics of charged particles in the near wake of a very negatively charged body -- Laboratory experiment and numerical simulation; Laboratory study of the electron temperature in the near wake of a conducting body; New model for auroral breakup during substorms; Substorm breakup on closed field lines; New model for substorm on sets -- The pre-breakup and triggering regimes; Model of the westward traveling surge and the generation of Pi 2 pulsations; Ionospheric electron acceleration by electromagnetic waves near regions of plasma resonances; Relativistic particle acceleration by obliquely propagating electromagnetic fields; Some consequences of intense electromagnetic wave injection into space plasmas.

  9. A comment on "the far future of exoplanet direct characterization"--the case for interstellar space probes.

    Science.gov (United States)

    Crawford, Ian A

    2010-10-01

    Following on from ideas presented in a recent paper by Schneider et al. on "The Far Future of Exoplanet Direct Characterization," I argue that they have exaggerated the technical obstacles to performing such "direct characterization" by means of fast (order 0.1c) interstellar space probes. A brief summary of rapid interstellar spaceflight concepts that may be found in the literature is presented. I argue that the presence of interstellar dust grains, while certainly something that will need to be allowed for in interstellar vehicle design, is unlikely to be the kind of showstopper suggested by Schneider et al. Astrobiology as a discipline would be a major beneficiary of developing an interstellar spaceflight capability, albeit in the longer term, and I argue that astrobiologists should keep an open mind to the possibilities.

  10. Reciprocal space XRD mapping with varied incident angle as a probe of structure variation within surface depth

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Qiguang [Norfolk State University; Williams, Frances [Norfolk State University; Zhao, Xin [JLAB; Reece, Charles E. [JLAB; Krishnan, Mahadevan [AASC, San Leandro, California

    2013-09-01

    In this study, we used a differential-depth X-Ray diffraction Reciprocal Spacing Mapping (XRD RSM) technique to investigate the crystal quality of a variety of SRF-relevant Nb film and bulk materials. By choosing different X-ray probing depths, the RSM study successfully revealed evolution the of materials microstructure after different materials processes, such as energetic condensation or surface polishing. The RSM data clearly measured the materials crystal quality at different thickness. Through a novel differential-depth RSM technique, this study found: I. for a heteroepitaxy Nb film Nb(100)/MgO(100), the film thickening process, via a cathodic arc-discharge Nb ion deposition, created a near-perfect single crystal Nb on the surfaces top-layer; II. for a mechanically polished single-crystal bulk Nb material, the microstructure on the top surface layer is more disordered than that in-grain.

  11. 33 CFR 164.80 - Tests, inspections, and voyage planning.

    Science.gov (United States)

    2010-07-01

    ... planning. 164.80 Section 164.80 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND..., and voyage planning. (a) The owner, master, or operator of each towing vessel of less than 1,600 GT... applicable; of chafing gear; and of the winch brake, if installed. (c)(1) The voyage-planning requirements...

  12. 46 CFR 188.10-35 - International voyage.

    Science.gov (United States)

    2010-10-01

    ... International Convention for Safety of Life at Sea, 1974, i.e., International voyage means a voyage from a country to which the present convention applies to a port outside such country, or conversely.” (c) The International Convention for Safety of Life at Sea, 1974, does not apply to vessels “solely navigating the...

  13. The body voyage as visual representation and art performance

    DEFF Research Database (Denmark)

    Olsén, Jan-Eric

    2011-01-01

    This paper looks at the notion of the body as an interior landscape that is made intelligible through visual representation. It discerns the key figure of the inner corporeal voyage, identifies its main elements and examines how contemporary artists working with performances and installations deal...... by the French artist Christian Boltanski, which gives a somewhat different meaning to the idea of the body voyage....

  14. Probing space-time structure of new physics with polarized beams at the international linear collider

    Indian Academy of Sciences (India)

    B Ananthanarayan

    2007-11-01

    At the international linear collider large beam polarization of both the electron and positron beams will enhance the signature of physics due to interactions that are beyond the standard model. Here we review our recently obtained results on a general model-independent method of determining for an arbitary one-particle inclusive state the space-time structure of such new physics through the beam polarization dependence and angular distribution of the final state particle.

  15. Full data acquisition in Kelvin Probe Force Microscopy: Mapping dynamic electric phenomena in real space

    Science.gov (United States)

    Collins, Liam; Belianinov, Alex; Somnath, Suhas; Balke, Nina; Kalinin, Sergei V.; Jesse, Stephen

    2016-08-01

    Kelvin probe force microscopy (KPFM) has provided deep insights into the local electronic, ionic and electrochemical functionalities in a broad range of materials and devices. In classical KPFM, which utilizes heterodyne detection and closed loop bias feedback, the cantilever response is down-sampled to a single measurement of the contact potential difference (CPD) per pixel. This level of detail, however, is insufficient for materials and devices involving bias and time dependent electrochemical events; or at solid-liquid interfaces, where non-linear or lossy dielectrics are present. Here, we demonstrate direct recovery of the bias dependence of the electrostatic force at high temporal resolution using General acquisition Mode (G-Mode) KPFM. G-Mode KPFM utilizes high speed detection, compression, and storage of the raw cantilever deflection signal in its entirety at high sampling rates. We show how G-Mode KPFM can be used to capture nanoscale CPD and capacitance information with a temporal resolution much faster than the cantilever bandwidth, determined by the modulation frequency of the AC voltage. In this way, G-Mode KPFM offers a new paradigm to study dynamic electric phenomena in electroactive interfaces as well as a promising route to extend KPFM to the solid-liquid interface.

  16. Weak Lensing from Space I: Prospects for The Supernova/Acceleration Probe

    CERN Document Server

    Rhodes, J; Aldering, G; Amanullah, R; Astier, Pierre; Barrelet, E; Bebek, C; Bergstr, L; Bercovitz, J; Bester, M; Bonissent, A; Bower, C; Carithers, W C; Commins, Eugene D; Day, C; Deustua, S; Di Gennaro, R S; Ealet, A; Eriksson, M; Fruchter, A S; Genat, J F; Goldhaber, G; Goobar, A; Groom, D; Harris, S; Harvey, P; Heetderks, H; Holland, S; Huterer, D; Karcher, A; Kolbe, W F; Krieger, B; Lafever, R; Lamoureux, J; Levi, M; Levin, D; Linder, E V; Loken, S; Malina, R; McKee, S; Miquel, R; Mostek, N; Mufson, S L; Musser, J; Nugent, P; Oluseyi, H; Pain, R; Palaio, N; Pankow, D; Perlmutter, S; Pratt, R; Prieto, E; Robinson, K; Roe, N; Sholl, M; Schubnell, M S; Smadja, G; Smoot, G F; Spadafora, A; Tarl, G; Tomasch, A; Von der Lippe, H; Vincent, D; Walder, J P; Wang, G; Rhodes, Jason; Refregier, Alexandre; Massey, Richard

    2003-01-01

    The proposed Supernova/Acceleration Probe (SNAP) satellite has been recognized as an ideal instrument to measure the accelerating expansion of the universe through the distance moduli to type Ia supernovae. We show that SNAP will also be excellent for surveys of weak gravitational lensing by large-scale structure. Many of the requirements for precise photometry are compatible with those to accurately measure the shapes of background galaxies. We describe two surveys to be performed by SNAP. A 15 square degree ``deep'' survey will find clusters/groups and allow two-and three-dimensional dark matter maps to be made. A 300 square degree ``wide'' survey will be used to provide global constraints on cosmological parameters including Omega_M and w, the dark energy equation of state parameter. Both surveys will be conducted in 9 wide-band optical and near-IR filters, enabling photometric redshifts to be calculated. This first paper in a three part series outlines the survey strategies and introduces the SNAP instrum...

  17. Availability of feature-oriented scanning probe microscopy for remote-controlled measurements on board a space laboratory or planet exploration Rover.

    Science.gov (United States)

    Lapshin, Rostislav V

    2009-06-01

    Prospects for a feature-oriented scanning (FOS) approach to investigations of sample surfaces, at the micrometer and nanometer scales, with the use of scanning probe microscopy under space laboratory or planet exploration rover conditions, are examined. The problems discussed include decreasing sensitivity of the onboard scanning probe microscope (SPM) to temperature variations, providing autonomous operation, implementing the capabilities for remote control, self-checking, self-adjustment, and self-calibration. A number of topical problems of SPM measurements in outer space or on board a planet exploration rover may be solved via the application of recently proposed FOS methods.

  18. Probing Hawking and Unruh effects and quantum field theory in curved space by geometric invariants

    CERN Document Server

    Capolupo, Antonio

    2013-01-01

    The presence of noncyclic geometric invariant is revealed in all the phenomena where particle generation from vacuum or vacuum condensates appear. Aharonov--Anandan invariants then can help to study such systems and can represent a new tool to be used in order to provide laboratory evidence of phenomena particulary hard to be detected, such as Hawking and Unruh effects and some features of quantum field theory in curved space simulated by some graphene morphologies. It is finally suggested that a very precise quantum thermometer can be built by exploiting geometric invariants properties.

  19. New local interstellar spectra for protons, Helium and Carbon computed from Voyager 1 and PAMELA observations

    Science.gov (United States)

    Bisschoff, Driaan; Potgieter, Marius

    2016-07-01

    The comparison of computed galactic spectra with experimental, in situ data at lower energies is finally possible with the cosmic ray observations made by the Voyager 1 spacecraft outside the dominant modulating influence of the heliosphere. Galactic spectra computed by galactic propagation models and considered to be local interstellar spectra (LIS), for specifically protons, Helium and Carbon nuclei, can now be compared with observations at low energies (less than 100 MeV/nuc) from Voyager 1 and at high energies (above 30 GeV/nuc) from the PAMELA space detector at the Earth. We set out to reproduce the Voyager 1 observations beyond the heliopause using the GALPROP code and the PAMELA spectra at the Earth via a comprehensive solar modulation model. By varying the galactic diffusion parameters in the GALPROP plain diffusion model, specifically the rigidity dependence of spatial diffusion, and then including reacceleration in Galactic space, we compute spectra simultaneously for galactic protons, Helium and Carbon. These LIS are then used as input to a full 3D solar modulation model to test the spectra against the PAMELA measurements. We present new LIS, with expressions for the energy range of 3 MeV/nuc to 100 GeV/nuc, which should be most valuable for further solar modulation modelling.

  20. Voyager 1 observes low-energy galactic cosmic rays in a region depleted of heliospheric ions.

    Science.gov (United States)

    Stone, E C; Cummings, A C; McDonald, F B; Heikkila, B C; Lal, N; Webber, W R

    2013-07-12

    On 25 August 2012, Voyager 1 was at 122 astronomical units when the steady intensity of low-energy ions it had observed for the previous 6 years suddenly dropped for a third time and soon completely disappeared as the ions streamed away into interstellar space. Although the magnetic field observations indicate that Voyager 1 remained inside the heliosphere, the intensity of cosmic ray nuclei from outside the heliosphere abruptly increased. We report the spectra of galactic cosmic rays down to ~3 × 10(6) electron volts per nucleon, revealing H and He energy spectra with broad peaks from 10 × 10(6) to 40 × 10(6) electron volts per nucleon and an increasing galactic cosmic-ray electron intensity down to ~10 × 10(6) electron volts.

  1. Narrowing the conformational space sampled by two-domain proteins with paramagnetic probes in both domains

    Energy Technology Data Exchange (ETDEWEB)

    Dasgupta, Soumyasri; Hu Xiaoyu [University of Florence, Magnetic Resonance Center (CERM) (Italy); Keizers, Peter H. J.; Liu Weimin [Leiden University, Leiden Institute of Chemistry, Gorlaeus Laboratories (Netherlands); Luchinat, Claudio, E-mail: luchinat@cerm.unifi.it; Nagulapalli, Malini [University of Florence, Magnetic Resonance Center (CERM) (Italy); Overhand, Mark [Leiden University, Leiden Institute of Chemistry, Gorlaeus Laboratories (Netherlands); Parigi, Giacomo [University of Florence, Magnetic Resonance Center (CERM) (Italy); Sgheri, Luca [Istituto per le Applicazioni del Calcolo, Sezione di Firenze, CNR (Italy); Ubbink, Marcellus [Leiden University, Leiden Institute of Chemistry, Gorlaeus Laboratories (Netherlands)

    2011-11-15

    Calmodulin is a two-domain protein which in solution can adopt a variety of conformations upon reorientation of its domains. The maximum occurrence (MO) of a set of calmodulin conformations that are representative of the overall conformational space possibly sampled by the protein, has been calculated from the paramagnetism-based restraints. These restraints were measured after inclusion of a lanthanide binding tag in the C-terminal domain to supplement the data obtained by substitution of three paramagnetic lanthanide ions to the calcium ion in the second calcium binding loop of the N-terminal domain. The analysis shows that the availability of paramagnetic restraints arising from metal ions placed on both domains, reduces the MO of the conformations to different extents, thereby helping to identify those conformations that can be mostly sampled by the protein.

  2. k-space image correlation to probe the intracellular dynamics of gold nanoparticles

    Science.gov (United States)

    Bouzin, M.; Sironi, L.; Chirico, G.; D'Alfonso, L.; Inverso, D.; Pallavicini, P.; Collini, M.

    2016-04-01

    The collective action of dynein, kinesin and myosin molecular motors is responsible for the intracellular active transport of cargoes, vesicles and organelles along the semi-flexible oriented filaments of the cytoskeleton. The overall mobility of the cargoes upon binding and unbinding to motor proteins can be modeled as an intermittency between Brownian diffusion in the cell cytoplasm and active ballistic excursions along actin filaments or microtubules. Such an intermittent intracellular active transport, exhibited by star-shaped gold nanoparticles (GNSs, Gold Nanostars) upon internalization in HeLa cancer cells, is investigated here by combining live-cell time-lapse confocal reflectance microscopy and the spatio-temporal correlation, in the reciprocal Fourier space, of the acquired image sequences. At first, the analytical theoretical framework for the investigation of a two-state intermittent dynamics is presented for Fourier-space Image Correlation Spectroscopy (kICS). Then simulated kICS correlation functions are employed to evaluate the influence of, and sensitivity to, all the kinetic and dynamic parameters the model involves (the transition rates between the diffusive and the active transport states, the diffusion coefficient and drift velocity of the imaged particles). The optimal procedure for the analysis of the experimental data is outlined and finally exploited to derive whole-cell maps for the parameters underlying the GNSs super-diffusive dynamics. Applied here to the GNSs subcellular trafficking, the proposed kICS analysis can be adopted for the characterization of the intracellular (super-) diffusive dynamics of any fluorescent or scattering biological macromolecule.

  3. Gravity field estimation from future space missions - TOPEX/POSEIDON, Gravity Probe B, and ARISTOTELES

    Science.gov (United States)

    Pavlis, Erricos C.

    Accurate knowledge of the gravity field is a firm requirement in any study of Planet Earth. Space techniques have so far demonstrated their superiority in the global mapping of the gravity field based on ground tracking and altimeter data mostly. Numerical and analytical simulation studies of the upcoming geophysically relevant missions that will most likely carry GPS receivers, indicate significant improvements in the accuracy as well as the resolution of the gravity field. TOPEX will improve by some two orders of magnitude the long wavelength part (to degree about 20), while GP-B will contribute in the long as well as medium wavelength part of the spectrum (up to degree about 60). The gradiometer measurements on ARISTOTELES will contribute in the medium and short wavelength regions (from degree 30 up); GPS tracking of the spacecraft though will provide additional information for the long wavelength gravity and will help resolve it to accuracies comparable to those obtained from GP-B. With the mean rms coefficient error per degree kept below 10 exp -10, geophysical signals such as the post-glacial rebound, tidal variations, and secular and periodic variations of the zonal field rise above the noise level and become readily observable processes.

  4. The predictability of the "Voyager" accident

    Directory of Open Access Journals (Sweden)

    L. Bertotti

    2008-05-01

    Full Text Available On 14 February 2005 a severe mistral storm caused substantial damage to the passenger cruiser "Voyager" between Balearic Islands and Sardinia. The storm had been well predicted. However, the ship was hit by one or more, apparently unexpected, large waves. Our aim was to understand if this was a freak event or it was within the expectable probability. At this aim we use our best estimate of the local wave conditions, obtained combining modelling and measured data. Starting from these we derive the probability of large waves, considering both linear and non-linear cases. Notwithstanding a correction towards the worse of the, otherwise inconsistent, available reports, on the basis of the data at disposal we conclude that, given the local conditions, the event was within the range of the potentially expectable wave heights. This turns out to be even more the case on the basis of recent results based on theoretical and experimental data.

  5. Interstellar Probe: The Next Step To Flight

    Science.gov (United States)

    McNutt, Ralph; Zurbuchen, Thomas H.

    2016-07-01

    In the years following the discovery of the solar wind, the term "heliosphere" was coined and defined as "the region of interplanetary space where the solar wind is flowing supersonically." In June 1971, with the development of the Pioneer probes to Jupiter and beyond well underway, a session of the American Astronautical Society meeting considered scientific exploration reaching beyond the solar system and into the interstellar medium. Despite many discussions, studies, and meetings since, the most recent held under the auspices of the Keck Institute for Space Studies (8-11 September 2014 and 13-15 January 2015), such missions have been relegated to the '"future" due to the large distances and solar system escape speeds contemplated for their execution. In the meantime, the Voyager Interstellar Mission (VIM), consisting of the twin Voyager spacecraft almost 40 years since their respective launches, are making inroads into this region beyond the termination shock of the solar wind, a new region of the solid bodies of the solar system has been opened by the New Horizons flyby of the Pluto system, and the Cassini Ion and Neutral CAmera (INCA) and Interstellar Boundary Explorer (IBEX) have remotely sensed neutral atoms that have provided significant clues to the global structure of the interaction of the solar wind and interstellar medium. It is now time for a dedicated mission to the regime beyond the solar system to explore our galactic environment. A first, near-term implementation can be carried out with the near-current flight system technology. What is also clear is that the high speeds required will limit the spacecraft to a relatively small mass of no more than ~500 kg, regardless of the propulsion details. The recent success of the New Horizons mission at the Pluto system illustrates that with modern technologies, such spacecraft sizes can still accommodate the means to produce paradigm-shifting science, providing for a compelling scientific mission. The

  6. U.S. Arctic Voyage Planning Guide (AVPG)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Arctic Voyage Planning Guide is a compilation of official U.S. Government information and references to sources of information that may be consulted by mariners...

  7. Reconnection at the Heliopause: Predictions for Voyager 2

    Science.gov (United States)

    Fuselier, S. A.; Cairns, I. H.

    2017-09-01

    Predicted and observed properties of the inner and outer heliosheath were recently used to assess whether magnetic reconnection was occurring at the Voyager 1 crossing of the heliopause. It was concluded that reconnection may not have been occurring locally, but may have been occurring at a location remote from Voyager 1. Here observations of 37 to 70 keV electrons measured by the LECP instrument on Voyager 1 are interpreted as possible evidence for remote reconnection and the study is extended to the heliopause near the projected crossing location of Voyager 2, where the plasma depletion layer (PDL) should be significantly stronger. The predicted plasma properties are used to determine if local reconnection is possible at this projected heliopause crossing.

  8. Voyager: Exploratory Analysis via Faceted Browsing of Visualization Recommendations.

    Science.gov (United States)

    Wongsuphasawat, Kanit; Moritz, Dominik; Anand, Anushka; Mackinlay, Jock; Howe, Bill; Heer, Jeffrey

    2016-01-01

    General visualization tools typically require manual specification of views: analysts must select data variables and then choose which transformations and visual encodings to apply. These decisions often involve both domain and visualization design expertise, and may impose a tedious specification process that impedes exploration. In this paper, we seek to complement manual chart construction with interactive navigation of a gallery of automatically-generated visualizations. We contribute Voyager, a mixed-initiative system that supports faceted browsing of recommended charts chosen according to statistical and perceptual measures. We describe Voyager's architecture, motivating design principles, and methods for generating and interacting with visualization recommendations. In a study comparing Voyager to a manual visualization specification tool, we find that Voyager facilitates exploration of previously unseen data and leads to increased data variable coverage. We then distill design implications for visualization tools, in particular the need to balance rapid exploration and targeted question-answering.

  9. IS VOYAGER 1 INSIDE AN INTERSTELLAR FLUX TRANSFER EVENT?

    Energy Technology Data Exchange (ETDEWEB)

    Schwadron, N. A. [University of New Hampshire, 105 Main Street, Durham, NH 03824 (United States); McComas, D. J., E-mail: n.schwadron@unh.edu [Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238-5166 (United States)

    2013-12-01

    Plasma wave observations from Voyager 1 have recently shown large increases in plasma density, to about 0.1 cm{sup –3}, consistent with the density of the local interstellar medium. However, corresponding magnetic field observations continue to show the spiral magnetic field direction observed throughout the inner heliosheath. These apparently contradictory observations may be reconciled if Voyager 1 is inside an interstellar flux transfer event—similar to flux transfer events routinely seen at the Earth's magnetopause. If this were the case, Voyager 1 remains inside the heliopause and based on the Voyager 1 observations we can determine the polarity of the interstellar magnetic field for the first time.

  10. The maiden voyage of enterprise systems and micro foundational institutionalism

    DEFF Research Database (Denmark)

    Svejvig, Per

    This short paper presents an in-progress research work aimed at establishing a theoretical lens for describing, understanding and explaining the period from going live with an enterprise system and until this system is stabilized and normal organizational performance is achieved - this period is ...... is metaphorically labeled the maiden voyage. The paper presents a short overview of institutional theory, and proposes methodologically guidelines for investigating the maiden voyage by institutional theory....

  11. Deep-space probes

    CERN Document Server

    Matloff, Gregory L

    2000-01-01

    This excellent book by Dr Gregory Matloff could be viewed as a large multi­ disciplinary compendium of past research, current investigations and future research in astronautics. However, unlike conventional works that are usually closed, this book is an open guide in three main respects: it contains progressive exercises as the chapter and section topics evolve, it provides the reader with many updated references, and it clearly indicates projected research areas that could become current research in the near future. For a student, the included exercises could be transformed into small worksheets or notebooks featuring many modern symbolic or algebraic computation systems that run on desktop or laptop computers. Thus, rapid and progressive study is possible - a sort of learning library driven by the author and by the bibliography at the end of each chapter. More than 340 references for both professionals and students have been selected to provide the reader with a sound basis for expanding his or her knowled...

  12. Observed Coupling Between the International Space Station PCU Plasma and a FPMU Langmuir Probe Facilitated by the Geomagnetic Field

    Science.gov (United States)

    Hartman, William; Koontz, Steven L.

    2010-01-01

    Electrical charging of the International Space Station (ISS) is a matter of serious concern resulting from the possibility of vehicle arcing and electrical shock hazard to crew during extravehicular activity (EVA). A Plasma Contactor Unit (PCU) was developed and integrated into ISS in order to control the ISS floating potential, thereby, minimize vehicle charging and associated hazards. One of the principle factors affecting ISS electrical charging is the ionosphere plasma state (i.e., electron temperature and density). To support ISS electrical charging studies a Floating Potential Monitoring Unit (FPMU) is also integrated into ISS in order to measure the ionosphere properties using Langmuir probes (LP). The FPMU was located on the Starboard side of ISS. The PCU is located near the center of ISS with its plasma exhaust pointed to port. From its integration on ISS in 2006 through November of 2009, the FPMU data exhibited nominal characteristics during PCU operation. On November 21, 2009 the FPMU was relocated from the Starboard location to a new Port location. After relocation significant enhanced noise was observed in both the LP current-voltage sweeps and the derived electron temperature data. The enhanced noise only occurred when the PCU was in discharge and at unique and repeatable locations of the ISS orbit. The cause of this enhanced noise was investigated. It was found that there is coupling occurring between the PCU plasma and the FPMU LP. In this paper we shall 1) present the on-orbit data and the presence of enhanced noise, 2) demonstrate that the coupling of the PCU plasma and the FPMU measurements is geomagnetically organized, 3) show that coupling of the PCU plasma and the FPMU is primarily due to and driven by particle-wave interaction and 4) show that the ionosphere conditions are adequate for Alfven waves to be generated by the PCU plasma.

  13. Pioneer and Voyager observations of Forbush decreases between 6 and 24 AU

    Science.gov (United States)

    Mcdonald, F. B.; Trainor, J. H.; Webber, W. R.

    1982-01-01

    A detailed phenomenological description of deep space Forbush decreases is given, using Voyager and Pioneer data. The transient reduction in cosmic ray intensity can be produced by (1) reflection at the shock front; (2) increased modulation associated with the disturbed region behind the shock; (3) a barrier mechanism involving large-scale tangential discontinuities; or (4) particle drifts in the enhanced magnetic field by the post-shock region. The presence of a well-defined precursor peak clearly indicates that particle reflection is important. Forbush decreases appear to be an important component in the long-term modulation.

  14. NASA's Space Radiation Laboratory

    Institute of Scientific and Technical Information of China (English)

    Shelley Canright; 陈功

    2004-01-01

    @@ Imagine a human spacecraft crew voyaging through space. A satellite sends a warning; energetic particles are being accelerated from the Sun's corona①,sending dangerous radiation toward the spacecraft, but the crewmembers aren't worried. Long before their journey, researchers on Earth conducted experiments to accurately measure the hazards of space radiation and developed new materials and countermeasures to protect them.

  15. Measuring the local ISM along the sight lines of the two Voyager spacecraft with HST/STIS

    Science.gov (United States)

    Zachary, Julia; Redfield, Seth; Linsky, Jeffrey

    2017-01-01

    In August 2012, Voyager 1 crossed the heliopause, becoming the first human-made object to exit the Solar System. This milestone signifies the beginning of an important new era for local interstellar medium (LISM) discoveries. We present measurements of the structure and composition of the LISM by using high-resolution Hubble Space Telescope spectra of nearby stars that lie along the same lines of sight as the respective paths of the Voyager spacecraft. We provide a comprehensive inventory of LISM absorption in the near-ultraviolet (2600-2800Å) and the far-ultraviolet (1200-1500Å). The LISM absorption profiles are used to make comparisons between each pair of closely spaced (NAS 5-26555.

  16. Conductivity Probe

    Science.gov (United States)

    2008-01-01

    The Thermal and Electrical Conductivity Probe (TECP) for NASA's Phoenix Mars Lander took measurements in Martian soil and in the air. The needles on the end of the instrument were inserted into the Martian soil, allowing TECP to measure the propagation of both thermal and electrical energy. TECP also measured the humidity in the surrounding air. The needles on the probe are 15 millimeters (0.6 inch) long. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  17. Comparative analysis and approximations of space-charge formation in Langmuir probes with plane, cylindrical and spherical electrodes including temperature effects

    Energy Technology Data Exchange (ETDEWEB)

    Valdeblanquez, Eder [Departamento de Fisica, Facultad de IngenierIa, Universidad del Zulia, Apartado 4011- A 526, Maracaibo, Venezuela and Centro de Investigacion de Matematicas Aplicadas Facultad de IngenierIa, Universidad del Zulia, Apartado 10486, Maracaibo (Venezuela, Bolivarian Republic of)], E-mail: eder@luz.edu.ve

    2008-10-15

    In this paper the space-charge effects in Langmuir probes are compared for different kinds of symmetries: plane, cylindrical and spherical. A detailed analysis is performed here including temperature effects, and therefore kinetic theory is used instead of fluid equations as used by other authors. The nonlinear equations obtained here have been solved first by numerical computation and later by approximations using Bessel functions. The accuracy of each approximation is also discussed. Space-charge effects are more important in plane geometries than in the case of cylindrical or spherical symmetries.

  18. Miniature Sensor Probe for O2, CO2, and H2O Monitoring in Space Suits Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced space suit technologies require lightweight, low-power, durable sensors for monitoring critical life support constituents. Current technology cannot provide...

  19. Tramp ship routing and scheduling with voyage separation requirements

    DEFF Research Database (Denmark)

    Vilhelmsen, Charlotte; Lusby, Richard Martin; Larsen, Jesper

    2017-01-01

    In this paper we explore tramp ship routing and scheduling. Tramp ships operate much like taxies following the available demand. Tramp operators can determine some of their demand in advance by entering into long-term contracts and then try to maximise profits from optional voyages found in the s......In this paper we explore tramp ship routing and scheduling. Tramp ships operate much like taxies following the available demand. Tramp operators can determine some of their demand in advance by entering into long-term contracts and then try to maximise profits from optional voyages found...... in the spot market. Routing and scheduling a tramp fleet to best utilise fleet capacity according to current demand is therefore an ongoing and complicated problem. Here we add further complexity to the routing and scheduling problem by incorporating voyage separation requirements that enforce a minimum time...... spread between some voyages. The incorporation of these separation requirements helps balance the conflicting objectives of maximising profit for the tramp operator and minimising inventory costs for the charterer, since these costs increase if similar voyages are not performed with some separation...

  20. Solar-Heliospheric-Interstellar Cosmic Ray Tour with the NASA Virtual Energetic Particle Observatory and the Space Physics Data Facility

    Science.gov (United States)

    Cooper, John F.; Papitashvili, Natalia E.; Johnson, Rita C.; Lal, Nand; McGuire, Robert E.

    2015-04-01

    NASA now has a large collection of solar, heliospheric, and local interstellar (Voyager 1) cosmic ray particle data sets that can be accessed through the data system services of the NASA Virtual Energetic Particle Observatory (VEPO) in collaboration with the NASA Space Physics Data Facility SPDF), respectively led by the first and last authors. The VEPO services were developed to enhance the long-existing OMNIWeb solar wind and energetic particle services of SPDF for on-line browse, correlative, and statistical analysis of NASA and ESA mission fields, plasma, and energetic particle data. In this presentation we take of tour through VEPO and SPDF of SEP reservoir events, the outer heliosphere earlier surveyed by the Pioneer, Voyager, and Ulysses spacecraft and now being probed by New Horizons, and the heliosheath-heliopause-interstellar regions now being explored by the Voyagers and IBEX. Implications of the latter measurements are also considered for the flux spectra of low to high energy cosmic rays in interstellar space.

  1. Are you there, Planet X? It's me, Voyager 1

    CERN Document Server

    Iorio, Lorenzo

    2014-01-01

    We propose to use the navigation data of Voyager 1 collected during the latest three decades to put on the test the recently proposed hypothesis that one (or more) still unseen super-Earth(s) may lurk at about $200-250$ Astronomical Units. Such a hypothetical body would perturb the range of Voyager 1 up to several hundreds of km over 30 years. Even if two-way coherent range and Doppler tracking were discontinued for Voyager 1 after the planetary flybys era due to cost reasons, it does not seems unrealistic to assume a ranging accuracy still better than 1 km. It would be fully adequate to put new, severe constraints on the existence of a hypothetical perturber with the physical and orbital characteristic recently suggested in the literature.

  2. In situ observations of interstellar plasma with Voyager 1.

    Science.gov (United States)

    Gurnett, D A; Kurth, W S; Burlaga, L F; Ness, N F

    2013-09-27

    Launched over 35 years ago, Voyagers 1 and 2 are on an epic journey outward from the Sun to reach the boundary between the solar plasma and the much cooler interstellar medium. The boundary, called the heliopause, is expected to be marked by a large increase in plasma density, from about 0.002 per cubic centimeter (cm(-3)) in the outer heliosphere, to about 0.1 cm(-3) in the interstellar medium. On 9 April 2013, the Voyager 1 plasma wave instrument began detecting locally generated electron plasma oscillations at a frequency of about 2.6 kilohertz. This oscillation frequency corresponds to an electron density of about 0.08 cm(-3), very close to the value expected in the interstellar medium. These and other observations provide strong evidence that Voyager 1 has crossed the heliopause into the nearby interstellar plasma.

  3. Reconstruction of the Voyager 2 Neptune Encounter in the ICRF System

    Science.gov (United States)

    Jacobson, Robert A.

    2008-01-01

    The Neptunian system was visited by the Voyager 2 spacecraft in August of 1989. We have re-examined the Voyager mission taking advantage of improvements made in dynamical and observational modelling and data processing.

  4. Interstellar Mapping and Acceleration Probe (IMAP)

    Science.gov (United States)

    Schwadron, N. A.; Opher, M.; Kasper, J.; Mewaldt, R.; Moebius, E.; Spence, H. E.; Zurbuchen, T. H.

    2016-11-01

    Our piece of cosmic real estate, the heliosphere, is the domain of all human existence - an astrophysical case history of the successful evolution of life in a habitable system. By exploring our global heliosphere and its myriad interactions, we develop key physical knowledge of the interstellar interactions that influence exoplanetary habitability as well as the distant history and destiny of our solar system and world. IBEX is the first mission to explore the global heliosphere and in concert with Voyager 1 and Voyager 2 is discovering a fundamentally new and uncharted physical domain of the outer heliosphere. In parallel, Cassini/INCA maps the global heliosphere at energies (˜5-55 keV) above those measured by IBEX. The enigmatic IBEX ribbon and the INCA belt were unanticipated discoveries demonstrating that much of what we know or think we understand about the outer heliosphere needs to be revised. This paper summarizes the next quantum leap enabled by IMAP that will open new windows on the frontier of Heliophysics at a time when the space environment is rapidly evolving. IMAP with 100 times the combined resolution and sensitivity of IBEX and INCA will discover the substructure of the IBEX ribbon and will reveal, with unprecedented resolution, global maps of our heliosphere. The remarkable synergy between IMAP, Voyager 1 and Voyager 2 will remain for at least the next decade as Voyager 1 pushes further into the interstellar domain and Voyager 2 moves through the heliosheath. Voyager 2 moves outward in the same region of sky covered by a portion of the IBEX ribbon. Voyager 2’s plasma measurements will create singular opportunities for discovery in the context of IMAP's global measurements. IMAP, like ACE before, will be a keystone of the Heliophysics System Observatory by providing comprehensive measurements of interstellar neutral atoms and pickup ions, the solar wind distribution, composition, and magnetic field, as well as suprathermal ion, energetic

  5. 46 CFR 108.209 - Hospital spaces.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hospital spaces. 108.209 Section 108.209 Shipping COAST... Construction and Arrangement Accommodation Spaces § 108.209 Hospital spaces. (a) Each unit carrying twelve or more persons on a voyage of more than three days must have a hospital space. (b) Each hospital space...

  6. Performance model of the Argonne Voyager multimedia server

    Energy Technology Data Exchange (ETDEWEB)

    Disz, T.; Olson, R.; Stevens, R. [Argonne National Lab., IL (United States). Mathematics and Computer Science Div.

    1997-07-01

    The Argonne Voyager Multimedia Server is being developed in the Futures Lab of the Mathematics and Computer Science Division at Argonne National Laboratory. As a network-based service for recording and playing multimedia streams, it is important that the Voyager system be capable of sustaining certain minimal levels of performance in order for it to be a viable system. In this article, the authors examine the performance characteristics of the server. As they examine the architecture of the system, they try to determine where bottlenecks lie, show actual vs potential performance, and recommend areas for improvement through custom architectures and system tuning.

  7. The body voyage as visual representation and art performance

    DEFF Research Database (Denmark)

    Olsén, Jan-Eric

    2011-01-01

    with it. A further aim with the paper is to discuss what kind of image of the body that is conveyed through medical visual technologies, such as endoscopy, and relate it to contemporary discussions on embodiment, embodied vision and bodily presence. The paper concludes with a recent exhibition......This paper looks at the notion of the body as an interior landscape that is made intelligible through visual representation. It discerns the key figure of the inner corporeal voyage, identifies its main elements and examines how contemporary artists working with performances and installations deal...... by the French artist Christian Boltanski, which gives a somewhat different meaning to the idea of the body voyage....

  8. Voyages et utopie scientifique dans La Nouvelle Atlantide de Bacon

    OpenAIRE

    2016-01-01

    Parce qu’il s’agit d’une fiction issue du genre utopique, la Nouvelle Atlantide est sans doute l’une des œuvres les plus originales du corpus baconien. Cet article s’efforce de montrer que ce récit de voyage et la philosophie du chancelier forment pourtant un tout cohérent, et que la Nouvelle Atlantide peut se lire comme une illustration fictionnelle de l’épistémologie baconienne. Pour Bacon, le voyage est à la fois la métaphore et l’instrument de la découverte scientifique. En effet la conna...

  9. The body voyage as visual representation and art performance.

    Science.gov (United States)

    Olsén, Jan Eric

    2011-01-01

    This paper looks at the notion of the body as an interior landscape that is made intelligible through visual representation. It discerns the key figure of the inner corporeal voyage, identifies its main elements and examines how contemporary artists working with performances and installations deal with it. A further aim with the paper is to discuss what kind of image of the body that is conveyed through medical visual technologies, such as endoscopy, and relate it to contemporary discussions on embodiment, embodied vision and bodily presence. The paper concludes with a recent exhibition by the French artist Christian Boltanski, which gives a somewhat different meaning to the idea of the body voyage.

  10. SEAC 2011 Stars and Stones: Voyages in Archaeoastronomy and Cultural Astronomy

    Science.gov (United States)

    Pimenta, F.; Ribeiro, N.; Silva, F.; Campion, N.; Joaquinito, A.; Tirapicos, L.

    2015-05-01

    Since Prehistory the sky has always been integrated as part of the cosmovision of human societies. The sky played a fundamental role not only in the orientation in space, time organization, ritual practices or celestial divination but also as an element of power. Migrations and voyages are intrinsic to humankind, they opened the routes for cultural diffusion and trade, but also for power dominance. Following these routes is also to follow cultural diversity and how human societies met or clashed. The sky and astronomical phenomena provided the tools for time reckoning, calendar organization and celestial navigation that supported those voyages. Astronomy gives us today the capacity to reproduce the sky, opening a window through which we can glimpse how those societies perceived, integrated and manipulated the sky into their world-views and their myths and, ultimately, into their social organization. A voyage is always a meeting of different worlds and eventually a process to accept diversity and thus we challenged the participants of the 19th meeting of the European Society for Astronomy in Culture to present their papers in the form of a voyage or an encounter for the following topics: - Techniques of celestial navigation and orientation of the past. Astronomical navigation and nautical instruments in the XIVth, XVth and XVIth centuries; - Expressions of astronomical knowledge in architecture and monuments, rock art, archaeology and landscape. People migration, a meeting between different cultures; - History of astronomy. An encounter between different conceptions; - Astronomy and the Jesuits. A meeting between different worlds; - Astronomy in antiquity. A meeting between different knowledge; - Ethno-astronomy, Cultural Astronomy and myths, voyages in space and in time through different cultures; - To where is Archaeoastronomy voyaging? A round table about Archaeoastronomy, Cultural Astronomy and Education. The 19th meeting of the European Society for Astronomy in

  11. Miniature Sensor Probe for O2, CO2, and H2O Monitoring in Space Suits Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced space suits require lightweight, low-power, durable sensors for monitoring critical life support materials. No current compact sensors have the tolerance...

  12. Science with the space-based interferometer eLISA. III: Probing the expansion of the Universe using gravitational wave standard sirens

    CERN Document Server

    Tamanini, Nicola; Barausse, Enrico; Sesana, Alberto; Klein, Antoine; Petiteau, Antoine

    2016-01-01

    We investigate the capability of various configurations of the space interferometer eLISA to probe the late-time background expansion of the universe using gravitational wave standard sirens. We simulate catalogues of standard sirens composed by massive black hole binaries whose gravitational radiation is detectable by eLISA, and which are likely to produce an electromagnetic counterpart observable by future surveys. The main issue for the identification of a counterpart resides in the capability of obtaining an accurate enough sky localisation with eLISA. This seriously challenges the capability of four-link (2 arm) configurations to successfully constrain the cosmological parameters. Conversely, six-link (3 arm) configurations have the potential to provide a test of the expansion of the universe up to $z\\sim 8$ which is complementary to other cosmological probes based on electromagnetic observations only. In particular, in the most favourable scenarios, they can provide a significant constraint on $H_0$ at ...

  13. SPECTRAL EVOLUTION OF ANOMALOUS COSMIC RAYS AT VOYAGER 1 BEYOND THE TERMINATION SHOCK

    Energy Technology Data Exchange (ETDEWEB)

    Senanayake, U. K.; Florinski, V. [Department of Space Science and Center for Space Plasma and Aeronomic Research, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Cummings, A. C.; Stone, E. C., E-mail: uks0001@uah.edu, E-mail: vaf0001@uah.edu, E-mail: ace@srl.caltech.edu, E-mail: ecs@srl.caltech.edu [California Institute of Technology, Mail Code 290-17, Pasadena CA 91125 (United States)

    2015-05-01

    When the Voyager 1 spacecraft crossed the termination shock (TS) on 2004 December 16, the energy spectra of anomalous cosmic rays (ACRs) could not have been produced by steady-state diffusive shock acceleration. However, over the next few years, in the declining phase of the solar cycle, the spectra began to evolve into the expected power-law profile. Observations at the shock led to a broad range of alternative theories for ACR acceleration. In spite of that, in this work we show that the observations could be explained by assuming ACRs are accelerated at the TS. In this paper, we propose that the solar cycle had an important effect on the unrolling of the spectra in the heliosheath. To investigate the spectral evolution of ACRs, a magnetohydrodynamic background model with stationary solar-wind inner boundary conditions was used to model the transport of helium and oxygen ions. We used a backward-in-time stochastic integration technique where phase-space trajectories are integrated until the so-called “injection energy” is reached. Our simulation results were compared with Voyager 1 observations using three different diffusion models. It is shown that the spectral evolution of ACRs in the heliosheath at Voyager 1 could be explained by an increase in the source strength and an enhancement in diffusion as a result of a decrease of the turbulent correlation length in the declining phase of the solar cycle. At the same time, drift effects seem to have had a smaller effect on the evolution of the spectra.

  14. Heat stress: a major contributor to poor animal welfare associated with long-haul live export voyages.

    Science.gov (United States)

    Caulfield, Malcolm P; Cambridge, Heather; Foster, Susan F; McGreevy, Paul D

    2014-02-01

    Recent investigations by the Australian Department of Agriculture, Fisheries and Forestry into high mortalities on live export voyages from Australia to the Middle East during the Northern hemisphere summer suggest that animal welfare may be compromised by heat stress. The live export industry has generated a computer model that aims to assess the risk of heat stress and to contain mortality levels on live export ships below certain arbitrary limits. Although the model must be complied with under Australian law, it is not currently available for independent scientific scrutiny, and there is concern that model and the mandated space allowances are inadequate. This review appraises the relevant literature on heat stress in sheep and cattle, including laboratory studies aimed at mimicking the ambient temperatures and humidity levels likely to be encountered on live export voyages. Animal welfare is likely to be very poor as a result of heat stress in some shipments.

  15. Introducing Students to Darwin via the Voyage of HMS "Beagle"

    Science.gov (United States)

    Swab, Janice C.

    2010-01-01

    I use the diary that Darwin wrote during the voyage of HMS Beagle and recent images of a few of the places he visited to illustrate some comparisons between Darwin's world and ours. For today's students, increasingly committed to environmental issues, this may be an especially promising way to introduce Darwin.

  16. Voyages Through Time: Integrated science for high schools, Pamela Harman

    Science.gov (United States)

    Harman, Pamela; Devore, Edna

    Investigating the origin and evolution of the universe and life is a compelling theme for teaching science. It engages students in the key questions about change and the evidence for change over time, and offers a unifying theme for integrated science. "Voyages Through Time" is a high school integrated science curriculum on the theme of evolution. Six modules comprise the year-long course: Cosmic Evolution, Planetary Evolution, Origin of Life, Evolution of Life, and Evolution of Technology. A brief overview of the curriculum is presented. Participants conduct one or two activities representative of the six modules. Each workshop participant receives a sampler CD-ROM with a comprehensive overview of the curriculum, standards, and resources including complete lessons for use in the classroom. "Voyages Through Time" is being developed by a US team of scientists, educators, writers, and classroom teachers and students led by the SETI Institute partnered with NASA Ames Research Center, California Academy of Sciences and San Francisco State University. In 2000-2001 school year, "Voyages Through Time" was pilot tested (trialed) in high school classrooms in the San Francisco Bay Area, California. Following revisions, the curriculum was field tested (trialed) in 28 US states in more than 90 schools August 2001-June 2002. The final version is expected to be ready for publication by the beginning of 2003. "Voyages Through Time" is funded by the National Science Foundation (IMD # 9730693), NASA Astrobiology Institute, NASA Fundamental Biology, The Foundation for Microbiology, Educate America, and the Hewlett-Packard Company.

  17. Introducing Students to Darwin via the Voyage of HMS "Beagle"

    Science.gov (United States)

    Swab, Janice C.

    2010-01-01

    I use the diary that Darwin wrote during the voyage of HMS Beagle and recent images of a few of the places he visited to illustrate some comparisons between Darwin's world and ours. For today's students, increasingly committed to environmental issues, this may be an especially promising way to introduce Darwin.

  18. Implications of Voyager 1 observations beyond the heliopause for the local interstellar electron spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Bisschoff, D.; Potgieter, M. S., E-mail: 20056950@nwu.ac.za [Centre for Space Research, North-West University, 2520 Potchefstroom (South Africa)

    2014-10-20

    Cosmic-ray observations made by the Voyager 1 spacecraft outside the dominant modulating influence of the heliosphere finally allow the comparison of computed galactic spectra with experimental data at lower energies. These computed spectra, based on galactic propagation models, can now be compared with observations at low energies by Voyager 1 and at high energies by the PAMELA space detector at Earth. This improves understanding of basic propagation effects and also provides solar modulation studies with reliable input spectra from 1 MeV to 100 GeV. We set out to reproduce the Voyager 1 electron observations in the energy range of 6-60 MeV, as well as the PAMELA electron spectrum above 10 GeV, using the GALPROP code. By varying the source spectrum and galactic diffusion parameters, specifically the rigidity dependence of spatial diffusion, we find local interstellar spectra that agree with both power-law spectra observed by Voyager 1 beyond the heliopause. The local interstellar spectrum between ∼1 MeV and 100 GeV indicates that it is the combination of two power laws, with E {sup –(1.45} {sup ±} {sup 0.15)} below ∼100 MeV and E {sup –(3.15} {sup ±} {sup 0.05)} above ∼100 MeV. A gradual turn in the spectral shape matching the power laws is found, between 2.0 ± 0.5) GeV and (100 ± 10) MeV. According to our simplified modeling, this transition is caused primarily by galactic propagation effects. We find that the intensity beyond the heliopause at 10 MeV is (350 ± 50) electrons m{sup –2} s{sup –1} sr{sup –1} MeV{sup –1}, decreasing to (50 ± 5) electrons m{sup –2} s{sup –1} sr{sup –1} MeV{sup –1} at 100 MeV.

  19. COMPARISON OF PIONEER 10, VOYAGER 1, AND VOYAGER 2 ULTRAVIOLET OBSERVATIONS WITH ANTI-SOLAR LYMAN-ALPHA BACKSCATTER SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Fayock, B.; Zank, G. P.; Heerikhuisen, J., E-mail: brian.fayock@gmail.com, E-mail: garyp.zank@gmail.com, E-mail: jacob.heerikhuisen@uah.edu [Department of Physics and Center for Space Plasma and Aeronomic Research, University of Alabama in Huntsville, Huntsville, AL 35899 (United States)

    2013-09-20

    Observations made by ultraviolet (UV) detectors on board Pioneer 10, Voyager 1, and Voyager 2 can be used to analyze the distribution of neutral hydrogen throughout the heliosphere, including the interaction regions of the solar wind and local interstellar medium. Previous studies of the long-term trend of decreasing intensity with increasing heliocentric distance established the need for more sophisticated heliospheric models. Here we use state-of-the-art three-dimensional (3D) magnetohydrodynamic (MHD) neutral models to simulate Lyman-alpha backscatter as would be seen by the three spacecrafts, exploiting a new 3D Monte Carlo radiative transfer code under solar minimum conditions. Both observations and simulations of the UV backscatter intensity are normalized for each spacecraft flight path at {approx}15 AU, and we focus on the slope of decreasing intensity over an increasing heliocentric distance. Comparisons of simulations with Voyager 1 Lyman-alpha data results in a very close match, while the Pioneer 10 comparison is similar due to normalization, but not considered to be in agreement. The deviations may be influenced by a low resolution of photoionization in the 3D MHD-neutral model, a lack of solar cycle activity in our simulations, and possibly issues with instrumental sensitivity. Comparing the slope of Voyager 2 and the simulated intensities yields an almost identical match. Our results predict a large increase in the Lyman-alpha intensity as the hydrogen wall is approached, which would signal an imminent crossing of the heliopause.

  20. Modeling the Solar Wind at the Ulysses, Voyager, and New Horizons Spacecraft

    CERN Document Server

    Kim, T K; Zank, G P; Elliott, H A; McComas, D J

    2016-01-01

    The outer heliosphere is a dynamic region shaped largely by the interaction between the solar wind and the interstellar medium. While interplanetary magnetic field and plasma observations by the Voyager spacecraft have significantly improved our understanding of this vast region, modeling the outer heliosphere still remains a challenge. We simulate the three-dimensional, time-dependent solar wind flow from 1 to 80 astronomical units (AU), where the solar wind is assumed to be supersonic, using a two-fluid model in which protons and interstellar neutral hydrogen atoms are treated as separate fluids. We use 1-day averages of the solar wind parameters from the OMNI data set as inner boundary conditions to reproduce time-dependent effects in a simplified manner which involves interpolation in both space and time. Our model generally agrees with Ulysses data in the inner heliosphere and Voyager data in the outer heliosphere. Ultimately, we present the model solar wind parameters extracted along the trajectory of N...

  1. Solar Modulation of the Local Interstellar Spectrum with Voyager 1, AMS-02, PAMELA, and BESS

    Science.gov (United States)

    Corti, C.; Bindi, V.; Consolandi, C.; Whitman, K.

    2016-09-01

    In recent years, the increasing precision of direct cosmic rays measurements opened the door to high-sensitivity indirect searches of dark matter and to more accurate predictions for radiation doses received by astronauts and electronics in space. The key ingredients in the study of these phenomena are the knowledge of the local interstellar spectrum (LIS) of galactic cosmic rays and the understanding of how the solar modulation affects the LIS inside the heliosphere. Voyager 1, AMS-02, PAMELA, and BESS measurements of proton and helium fluxes provide valuable information, allowing us to shed light on the shape of the LIS and the details of the solar modulation during solar cycles 22-24. A new parametrization of the LIS is presented, based on the latest data from Voyager 1 and AMS-02. Using the framework of the force-field approximation, the solar modulation parameter is extracted from the time-dependent fluxes measured by PAMELA and BESS. A modified version of the force-field approximation with a rigidity-dependent modulation parameter is introduced, yielding better fits than the force-field approximation. The results are compared with the modulation parameter inferred by neutron monitors.

  2. The ISS as a platform for a fully simulated mars voyage

    Science.gov (United States)

    Narici, Livio; Reitz, Guenther

    2016-07-01

    The ISS can mimic the impact of microgravity, radiation, living and psychological conditions that astronauts will face during a deep space cruise, for example to Mars. This suggests the ISS as the most valuable "analogue" for deep space exploration. NASA has indeed suggested a 'full-up deep space simulation on last available ISS Mission: 6/7 crew for one year duration; full simulation of time delays & autonomous operations'. This idea should be pushed further. It is indeed conceivable to use the ISS as the final "analogue", performing a real 'dry-run' of a deep space mission (such as a mission to Mars), as close as reasonably possible to what will be the real voyage. This Mars ISS dry run (ISS4Mars) would last 500-800 days, mimicking most of the challenges which will be undertaken such as length, isolation, food provision, decision making, time delays, health monitoring diagnostic and therapeutic actions and more: not a collection of "single experiments", but a complete exploration simulation were all the pieces will come together for the first in space simulated Mars voyage. Most of these challenges are the same that those that will be encountered during a Moon voyage, with the most evident exceptions being the duration and the communication delay. At the time of the Mars ISS dry run all the science and technological challenges will have to be mostly solved by dedicated works. These solutions will be synergistically deployed in the dry run which will simulate all the different aspects of the voyage, the trip to Mars, the permanence on the planet and the return to Earth. During the dry run i) There will be no arrivals/departure of spacecrafts; 2) Proper communications delay with ground will be simulated; 3) Decision processes will migrate from Ground to ISS; 4) Permanence on Mars will be simulated. Mars ISS dry run will use just a portion of the ISS which will be totally isolated from the rest of the ISS, leaving to the other ISS portions the task to provide the

  3. Comparison of Metal-Backed Free-Space and Open-Ended Coaxial Probe Techniques for the Dielectric Characterization of Aeronautical Composites.

    Science.gov (United States)

    López-Rodríguez, Patricia; Escot-Bocanegra, David; Poyatos-Martínez, David; Weinmann, Frank

    2016-06-24

    The trend in the last few decades is that current unmanned aerial vehicles are completely made of composite materials rather than metallic, such as carbon-fiber or fiberglass composites. From the electromagnetic point of view, this fact forces engineers and scientists to assess how these materials may affect their radar response or their electronics in terms of electromagnetic compatibility. In order to evaluate this, electromagnetic characterization of different composite materials has become a need. Several techniques exist to perform this characterization, all of them based on the utilization of different sensors for measuring different parameters. In this paper, an implementation of the metal-backed free-space technique, based on the employment of antenna probes, is utilized for the characterization of composite materials that belong to an actual drone. Their extracted properties are compared with those given by a commercial solution, an open-ended coaxial probe (OECP). The discrepancies found between both techniques along with a further evaluation of the methodologies, including measurements with a split-cavity resonator, conclude that the implemented free-space technique provides more reliable results for this kind of composites than the OECP technique.

  4. Comparison of Metal-Backed Free-Space and Open-Ended Coaxial Probe Techniques for the Dielectric Characterization of Aeronautical Composites †

    Science.gov (United States)

    López-Rodríguez, Patricia; Escot-Bocanegra, David; Poyatos-Martínez, David; Weinmann, Frank

    2016-01-01

    The trend in the last few decades is that current unmanned aerial vehicles are completely made of composite materials rather than metallic, such as carbon-fiber or fiberglass composites. From the electromagnetic point of view, this fact forces engineers and scientists to assess how these materials may affect their radar response or their electronics in terms of electromagnetic compatibility. In order to evaluate this, electromagnetic characterization of different composite materials has become a need. Several techniques exist to perform this characterization, all of them based on the utilization of different sensors for measuring different parameters. In this paper, an implementation of the metal-backed free-space technique, based on the employment of antenna probes, is utilized for the characterization of composite materials that belong to an actual drone. Their extracted properties are compared with those given by a commercial solution, an open-ended coaxial probe (OECP). The discrepancies found between both techniques along with a further evaluation of the methodologies, including measurements with a split-cavity resonator, conclude that the implemented free-space technique provides more reliable results for this kind of composites than the OECP technique. PMID:27347966

  5. Comparison of Metal-Backed Free-Space and Open-Ended Coaxial Probe Techniques for the Dielectric Characterization of Aeronautical Composites

    Directory of Open Access Journals (Sweden)

    Patricia López-Rodríguez

    2016-06-01

    Full Text Available The trend in the last few decades is that current unmanned aerial vehicles are completely made of composite materials rather than metallic, such as carbon-fiber or fiberglass composites. From the electromagnetic point of view, this fact forces engineers and scientists to assess how these materials may affect their radar response or their electronics in terms of electromagnetic compatibility. In order to evaluate this, electromagnetic characterization of different composite materials has become a need. Several techniques exist to perform this characterization, all of them based on the utilization of different sensors for measuring different parameters. In this paper, an implementation of the metal-backed free-space technique, based on the employment of antenna probes, is utilized for the characterization of composite materials that belong to an actual drone. Their extracted properties are compared with those given by a commercial solution, an open-ended coaxial probe (OECP. The discrepancies found between both techniques along with a further evaluation of the methodologies, including measurements with a split-cavity resonator, conclude that the implemented free-space technique provides more reliable results for this kind of composites than the OECP technique.

  6. Voyages of Discovery through a Backpack Exchange

    Science.gov (United States)

    Syz, Tracy Hong

    2008-01-01

    Backpacks are commonplace in American schools. Each day students transport them to and from the classroom as they manage to carve out a little oasis of space to gather their treasures, homework and books. In Fair Lawn's recently launched Chinese classes, backpacks take on new responsibility, becoming culture bearers that connect middle school…

  7. Properties of the Plasma Surrounding the Global Heliosphere Determined with Voyager 1&2 ions and ENA/INCA Observations at E > 5 keV

    Science.gov (United States)

    Krimigis, S. M.; Dialynas, K.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

    2016-12-01

    The basic goal of the proposed Interstellar Mapping and Acceleration Probe (IMAP) is detailed scientific understanding of the Heliosheath (HS) and beyond, a region of space explored in situ by Voyager 1 (V1) since 2004, Voyager 2 (V2) since 2007, and remotely via energetic neutral atoms (ENA) by the Cassini/INCA (5.2-55 keV) since 2003 and IBEX (0.3-6 keV) since 2009. The partial overlap in energies (28 5 keV, the rest residing below that range, resulting in a beta (particle/magnetic pressure) always > 1, typically >10. (2) Based on the ENA-derived hot ion pressures, the interstellar magnetic field (ISMF) was predicted to be more than twice that expected in the literature i.e. similar to what was measured by V1 after crossing the heliopause (B 0.5 nT). (3) The width of the HS in the direction of V1 is 30 AU (predicted by INCA before the V1 HP crossing), but is thought to be larger (40-70 AU) in the southern ecliptic where V2, now 30 AU into the HS, currently travels. We address here the key question of the source of 5-55 keV ENAs that INCA measures. The analysis of INCA all-sky maps from 2003 to 2014 show that the decrease and recovery of ENA in the global heliosphere during this period (declining phase of SC23 and rise of SC24) is similar to that of the ions at V1/V2, consistent with the HS ions being the source of ENA. The close correspondence between ENA and ion spectra (despite the 140 AU distance between V1 and V2) as well as the similarity of ENA spectra over the nose and anti-nose directions, together with the recent V1 measurement of a BISMF 0.5nT, suggest that the global distributions of >5 keV ions in the heliosheath resembles a diamagnetic bubble with no significant tail-like feature (the alternative Parker 1961 model), also consistent with some recent MHD simulations and models.

  8. The Phase Space of z~1.2 SpARCS Clusters: Using Herschel to probe Dust Temperature as a Function of Environment and Accretion History

    CERN Document Server

    Noble, A G; Yee, H K C; Muzzin, A; Wilson, G; van der Burg, R F J; Balogh, M L; Shupe, D L

    2015-01-01

    We present a five-band Herschel study (100-500um) of three galaxy clusters at z~1.2 from the Spitzer Adaptation of the Red-Sequence Cluster Survey (SpARCS). With a sample of 120 spectroscopically-confirmed cluster members, we investigate the role of environment on galaxy properties utilizing the projected cluster phase space (line-of-sight velocity versus clustercentric radius), which probes the time-averaged galaxy density to which a galaxy has been exposed. We divide cluster galaxies into phase-space bins of (r/r200) x (v/sigma_v), tracing a sequence of accretion histories in phase space. Stacking optically star-forming cluster members on the Herschel maps, we measure average infrared star formation rates, and, for the first time in high-redshift galaxy clusters, dust temperatures for dynamically distinct galaxy populations---namely, recent infalls and those that were accreted onto the cluster at an earlier epoch. Proceeding from the infalling to virialized (central) regions of phase space, we find a steady...

  9. Probing the Solar System

    Science.gov (United States)

    Wilkinson, John

    2013-01-01

    Humans have always had the vision to one day live on other planets. This vision existed even before the first person was put into orbit. Since the early space missions of putting humans into orbit around Earth, many advances have been made in space technology. We have now sent many space probes deep into the Solar system to explore the planets and…

  10. Probing the Solar System

    Science.gov (United States)

    Wilkinson, John

    2013-01-01

    Humans have always had the vision to one day live on other planets. This vision existed even before the first person was put into orbit. Since the early space missions of putting humans into orbit around Earth, many advances have been made in space technology. We have now sent many space probes deep into the Solar system to explore the planets and…

  11. Solar cosmic ray measurements at high heliocentric latitudes. [proposed space missions of solar probes to study solar physics

    Science.gov (United States)

    Anderson, K. A.

    1976-01-01

    A brief review is presented of what might result from a program of solar cosmic ray observations on 'out-of-the-ecliptic' spacecraft. The following topics are discussed: (1) The magnetic fields of the sun at high latitudes, (2) propagation of fast charged particles in the solar corona and in interplanetary space at high latitudes, (3) origin of interplanetary particle populations and the solar wind, (4) other particle phenomena in interplanetary space (e.g., acceleration of shock waves), and (5) effect of spacecraft mission characteristics on solar cosmic ray studies at high latitudes. Maps of polar coronal magnetic fields are shown.

  12. Measuring planetary field parameters by scattered cubes from the Husar-5 rover: educational space probe construction for a field work mission with great number of 5 cm sized sensorcube units launched from the rover.

    Science.gov (United States)

    Lang, A.; Kocsis, A.; Gats, J.

    2015-10-01

    The Hunveyor-Husar project tries to keep step with the main trends in the space research, in our recent case with the so called MSSM (Micro Sized Space- Mothership) and NPSDR (Nano, Pico Space Devices and Robots). [1]Of course, we do not want to scatter the smaller probe-cubes from a mothership, but from the Husar rover, and to do it on the planetary surface after landing.

  13. Io plasma torus ion composition: Voyager, Galileo, and Cassini

    Science.gov (United States)

    Nerney, Edward G.; Bagenal, Fran; Steffl, Andrew J.

    2017-01-01

    The Io torus produces ultraviolet emissions diagnostic of plasma conditions. We revisit data sets obtained by the Voyager 1, Galileo, and Cassini missions at Jupiter. With the latest version (8.0) of the CHIANTI atomic database we analyze UV spectra to determine ion composition. We compare ion composition obtained from observations from these three missions with a theoretical model of the physical chemistry of the torus by Delamere et al. (2005). We find ion abundances from the Voyager data similar to the Cassini epoch, consistent with the dissociation and ionization of SO2, but with a slightly higher average ionization state for sulfur, consistent with the higher electron temperature measured by Voyager. This reanalysis of the Voyager data produces a much lower oxygen:sulfur ratio than earlier analysis by Shemansky (1988), which was also reported by Bagenal (1994). We derive fractional ion compositions in the center of the torus to be S+/Ne 5%, S++/Ne 20%, S+++/Ne 5%, O+/Ne 20%, O++/Ne 3%, and Σ(On+)/Σ(Sn+) 0.8, leaving about 10-15% of the charge as protons. The radial profile of ion composition indicates a slightly higher average ionization state, a modest loss of sulfur relative to oxygen, and Σ(On+)/Σ(Sn+) 1.2 at about 8 RJ, beyond which the composition is basically frozen in. The Galileo observations of UV emissions from the torus suggest that the composition in June 1996 may have comprised a lower abundance of oxygen than usual, consistent with observations made at the same time by the EUVE satellite.

  14. Un voyage révélateur

    Institute of Scientific and Technical Information of China (English)

    马晓倩

    2011-01-01

    @@ En première année universitaire, j'ai eu la chance de partir en France.J'avais gagné un voyage lors d'un concours.Cette première expérienceà l'étranger est restée gravée à jamais dans ma mémoire comme un merveilleux souvenir.

  15. Fortschritt als Fraktur im frühen Science Fiction Film. Metaphorologische Überlegungen zu Auf- und Einbrüchen in LE VOYAGE DANS LA LUNE und LE VOYAGE À TRAVERS L`IMPOSSIBLE von G. Méliès

    Directory of Open Access Journals (Sweden)

    Hartmann, Jörg

    2009-09-01

    Full Text Available Fantasies of man travelling into space form a main part of the popular movie genre ‘Science Fiction’. These celluloid visions are not only fantasies of improving transport, they also convey a meaning in a figurative sense. They can be seen as a modern adoption of one of humanities oldest metaphors, ‘life as a sea fare voyage’: the meaning, which was once expressed by this ‘nautical metaphor’, has been transferred and can nowadays be found in films, which show astro-nauts crossing the frontier from known space into the unknown space. In order to conclude on their attitude towards technological progress in the early 20th century, the two oldest space travel movies, Le Voyage dans la Lune (F 1902 and Le Voyage a Travers L’Impossible (F 1904 will be analyzed.

  16. MORE EVIDENCE THAT VOYAGER 1 IS STILL IN THE HELIOSPHERE

    Energy Technology Data Exchange (ETDEWEB)

    Gloeckler, G.; Fisk, L. A., E-mail: gglo@umich.edu [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143 (United States)

    2015-06-20

    The investigators of the Voyager mission currently exploring the heliosheath have concluded and announced that Voyager 1 (V1) has crossed the heliopause and is now in the interstellar medium. This conclusion is based primarily on the plasma wave observations of Gurnett et al., which reveal a plasma electron density that resembles the density expected in the local interstellar medium. Fisk and Gloeckler have disputed the conclusion that V1 has crossed the heliopause, pointing out that to account for all the V1 observations, particularly the magnetic field direction together with the density, it is necessary to conclude that the higher densities observed by Gurnett et al. are due to compressed solar wind. In this Letter it is shown that the model of Fisk and Gloeckler for the nose region of the heliosheath can account in detail for the intensity and spectral shape of Energetic Neutral Hydrogen observed by the Interstellar Boundary Explorer (IBEX) in the directions of V1 and Voyager 2 (V2). A key feature of the Fisk and Gloeckler model is the existence of a region in the heliosheath where the solar wind is compressed and heated, followed by a region where the solar wind is compressed but cold. The region of cold compressed solar wind provides a unique explanation for the low-energy IBEX observations, and since this is the region where V1 must now reside, the low-energy IBEX observations provide strong evidence that V1 is still in the heliosphere.

  17. Abundances of Jupiter's Trace Hydrocarbons from Voyager and Cassini

    Science.gov (United States)

    Nixon, C. A.; Achterberg, R. K.; Romani, P. N.; Allen, M.; Zhang, X.; Teanby, N. A.; Irwin, P. G. J.; Flasar, F. M.

    2010-01-01

    The flybys of Jupiter by the Voyager spacecraft in 1979, and over two decades later by Cassini in 2000, have provided us with unique datasets from two different epochs, allowing the investigation of seasonal change in the atmosphere. In this paper we model zonal averages of thermal infrared spectra from the two instruments, Voyager 1 IRIS and Cassini CIRS, to retrieve the vertical and meridional profiles of temperature, and the abundances of the two minor hydrocarbons, acetylene (C2H2) and ethane (C2H6). The spatial variation of these gases is controlled by both chemistry and dynamics, and therefore their observed distribution gives us an insight into both processes, We find that the two gases paint quite different pictures of seasonal change. Whilst the 2-D cross-section of C2H6 abundance is slightly increased and more symmetric in 2000 (northern summer solstice) compared to 1979 (northern fall equinox), the major trend of equator to pole increase remains. For C2H2 on tile other hand, the Voyager epoch exhibits almost no latitudinal variation, whilst the Cassini era shows a marked decrease polewards in both hemispheres. At the present time, these experimental findings are in advance of interpretation, as there are no published models of 2-D Jovian seasonal chemical variation available for comparison.

  18. Abundances of Jupiter's Trace Hydrocarbons from Voyager and Cassini

    Science.gov (United States)

    Nixon, C. A.; Achterberg, R. K.; Romani, P. N.; Allen, M.; Zhang, X.; Teanby, N. A.; Irwin, P. G. J.; Flasar, F. M.

    2010-01-01

    The flybys of Jupiter by the Voyager spacecraft in 1979, and over two decades later by Cassini in 2000, have provided us with unique datasets from two different epochs, allowing the investigation of seasonal change in the atmosphere. In this paper we model zonal averages of thermal infrared spectra from the two instruments, Voyager 1 IRIS and Cassini CIRS, to retrieve the vertical and meridional profiles of temperature, and the abundances of the two minor hydrocarbons, acetylene (C2H2) and ethane (C2H6). The spatial variation of these gases is controlled by both chemistry and dynamics, and therefore their observed distribution gives us an insight into both processes, We find that the two gases paint quite different pictures of seasonal change. Whilst the 2-D cross-section of C2H6 abundance is slightly increased and more symmetric in 2000 (northern summer solstice) compared to 1979 (northern fall equinox), the major trend of equator to pole increase remains. For C2H2 on tile other hand, the Voyager epoch exhibits almost no latitudinal variation, whilst the Cassini era shows a marked decrease polewards in both hemispheres. At the present time, these experimental findings are in advance of interpretation, as there are no published models of 2-D Jovian seasonal chemical variation available for comparison.

  19. Abundances of Jupiter's Trace Hydrocarbons From Voyager and Cassini

    CERN Document Server

    Nixon, Conor A; Romani, Paul N; Allen, Mark; Zhang, Xi; Teanby, Nicholas A; Irwin, Patrick G J; Flasar, F Michael; 10.1016/j.pss2010.05.08

    2010-01-01

    The flybys of Jupiter by the Voyager spacecraft in 1979, and over two decades later by Cassini in 2000, have provided us with unique datasets from two different epochs, allowing the investigation of seasonal change in the atmosphere. In this paper we model zonal averages of thermal infrared spectra from the two instruments, Voyager 1 IRIS and Cassini CIRS, to retrieve the vertical and meridional profiles of temperature, and the abundances of the two minor hydrocarbons, acetylene (C2H2) and ethane (C2H6). The spatial variation of these gases is controlled by both chemistry and dynamics, and therefore their observed distribution gives us an insight into both processes. We find that the two gases paint quite different pictures of seasonal change. Whilst the 2-D cross-section of C2H6 abundance is slightly increased and more symmetric in 2000 (northern summer solstice) compared to 1979 (northern fall equinox), the major trend of equator to pole increase remains. For C2H2 on the other hand, the Voyager epoch exhibi...

  20. Reality and language in The Voyage Out, by Virginia Woolf = Realidade e linguagem em The Voyage Out, de Virginia Woolf

    Directory of Open Access Journals (Sweden)

    Peter James Harris

    2010-01-01

    Full Text Available This article discusses one of Virginia Woolf’s greatest literary concerns: the difficulty of expressing human experience through language. The focus is on The Voyage Out, her first novel, published in 1915, particularly the conflicts and contrasts present not only in the trajectory of Rachel Vinrace, the main character, but also in the structure of the novel itself, which establish a constant tension between reality and language. Este artigo tem como objetivo discutir uma das maiores preocupações literárias de Virginia Woolf: a dificuldade de expressar a experiência humana por meio da linguagem. Focalizamos The Voyage Out, seu primeiro romance, publicado em 1915, com atenção especial para osconflitos e contrastes presentes tanto na trajetória de Rachel Vinrace, a personagem principal, como na própria estruturação do romance, que instauram a tensão constante entre realidade e linguagem.

  1. Voyage of discovery? A comment on Koch et al. "A voyage to Terra Australis: human-mediated dispersal of cats".

    Science.gov (United States)

    Andrew, Rose L; Smith, Deane; Gorrell, Jamieson C; Janes, Jasmine K

    2016-12-07

    The origins of feral cats in Australia may be understood with the help of molecular studies, but it is important that hypotheses be tested with appropriate sampling and methodology. We point out several shortcomings in the analysis by Koch et al. (BMC Evol Biol 15:262, 2015; A voyage to Terra Australis: human-mediated dispersal of cats. Dryad Digital Repository, 2015), present a reanalysis of part of the study and discuss the challenges of elucidating the early history of feral cats.

  2. Science with the space-based interferometer eLISA. III: probing the expansion of the universe using gravitational wave standard sirens

    Science.gov (United States)

    Tamanini, Nicola; Caprini, Chiara; Barausse, Enrico; Sesana, Alberto; Klein, Antoine; Petiteau, Antoine

    2016-04-01

    We investigate the capability of various configurations of the space interferometer eLISA to probe the late-time background expansion of the universe using gravitational wave standard sirens. We simulate catalogues of standard sirens composed by massive black hole binaries whose gravitational radiation is detectable by eLISA, and which are likely to produce an electromagnetic counterpart observable by future surveys. The main issue for the identification of a counterpart resides in the capability of obtaining an accurate enough sky localisation with eLISA. This seriously challenges the capability of four-link (2 arm) configurations to successfully constrain the cosmological parameters. Conversely, six-link (3 arm) configurations have the potential to provide a test of the expansion of the universe up to z ~ 8 which is complementary to other cosmological probes based on electromagnetic observations only. In particular, in the most favourable scenarios, they can provide a significant constraint on H0 at the level of 0.5%. Furthermore, (ΩM, ΩΛ) can be constrained to a level competitive with present SNIa results. On the other hand, the lack of massive black hole binary standard sirens at low redshift allows to constrain dark energy only at the level of few percent.

  3. Jules Verne Voyager: A Web Interactive Tool for Comparative Planetology

    Science.gov (United States)

    Estey, L.; Pappalardo, R.; Meertens, C.

    2004-12-01

    A Web interactive map tool called "Jules Verne Voyager" was originally developed in 1999 by UNAVCO and continues to evolve. The Voyager tool can easily be used for comparative planetology studies by grades 8-14. Thematic mapping datasets, now totaling about 70 Gb, can be accessed by the tool and include global-scale maps of the inner solar system planets and moons, plus Jupiter and the Galilean moons. The map images are viewed on a Web browser created on demand by the server system. On the client-side, only a Java-enabled browser is required, and the Voyager Java applet runs well with common browsers like Netscape, Mozilla, Opera, and Internet Explorer. The applet sends a key-value pair URL to the http://jules.unavco.org server which queues incoming requests and sends them to a bank of computers dedicated to map image creation. The engine for map image creation makes use of the "Generic Mapping Tools" (GMT) software of Paul Wessel and Walter Smith, followed by image conversion of the GMT-created PostScript to GIF for raster image export and display back on the client browser. Because of the GMT-based engine on the server system, the student user can easily create the same type of images from real planetary data that researchers create. The tool also gives a student the ability to switch background datasets and overlay certain other thematic datasets, thus providing a minimal GIS capability. To our knowledge, the map tool has not yet formally been used in a 8-14 classroom environment, though informal use by students and teachers in these grades suggest that it would be well received. The server system is currently capable of handing a moderate level of requests that would result from classroom use; for example, as a system benchmark, over 800 Voyager images were created and served in about an hour during a DLESE 2003 annual meeting workshop. The Voyager map tool is being used by instructors in earth science and comparative planetology as a means to create customized

  4. Determining Ship’s Safe Speed and Best Possible Speed for Sea Voyage Legs

    Directory of Open Access Journals (Sweden)

    Grzegorz Rutkowski

    2016-09-01

    Full Text Available The purpose and scope of this paper is to describe factors to consider when determining the ship’s safe speed as well as the best speed for the sea voyage legs including directions related to vessel speed that are given in ColRegs, voyage orders and charter parties. Author also tried to describe the definition for the following notions: ship maneuvering, ship handling, safe speed, best possible speed for sea voyage legs.

  5. Exploring the brain, looking for thoughts: on Asimov's second Fantastic Voyage.

    Science.gov (United States)

    Cassou-Noguès, Pierre

    2011-01-01

    The aim of this paper is to investigate various concerns which appear in Isaac Asimov's Fantastic Voyage II: Destination Brain. I will disregard his first voyage inside a human body in Fantastic Voyage I, which the author disavows as not being his own work. In contrast, the second voyage is intricate, suggesting problems drawn from a variety of sources. In a nutshell, Asimov's explorers enter the body of a comatose man in order to read his thoughts. The story can be related both to philosophical thought-experiments, such as those of Gottfried Wilhelm Leibniz and of Herbert Feigl, as well as to personal anxieties peculiar to Asimov.

  6. Abundances of Jupiter's Trace Hydrocarbons from Voyager and Cassini. Data Tables: Voyager IRIS Observations Planetary and Space Science, Forthcoming 2010

    Science.gov (United States)

    Nixon, C. A.; Achterberg, R. K.; Romani, P. N.; Allen, M.; Zhang, X.; Irwin, P. G. J.; Flasar, F. M.

    2010-01-01

    The following six tables give the retrieved temperatures and volume mixing ratios of C2H2 and C2H6 and the formal errors on these results from the retrieval, as described in the manuscript. These are in the form of two-dimensional tables, specified on a latitudinal and vertical grid. The first column is the pressure in bar, and the second column gives the altitude in kilometers calculated from hydrostatic equilibrium, and applies to the equatorial profile only. The top row of the table specifies the planetographic latitude.

  7. Abundances of Jupiter's Trace Hydrocarbons from Voyager and Cassini. Data Tables: Voyager IRIS Observations Planetary and Space Science, Forthcoming 2010

    Science.gov (United States)

    Nixon, C. A.; Achterberg, R. K.; Romani, P. N.; Allen, M.; Zhang, X.; Irwin, P. G. J.; Flasar, F. M.

    2010-01-01

    The following six tables give the retrieved temperatures and volume mixing ratios of C2H2 and C2H6 and the formal errors on these results from the retrieval, as described in the manuscript. These are in the form of two-dimensional tables, specified on a latitudinal and vertical grid. The first column is the pressure in bar, and the second column gives the altitude in kilometers calculated from hydrostatic equilibrium, and applies to the equatorial profile only. The top row of the table specifies the planetographic latitude.

  8. Synthesis-enabled probing of mitosene structural space leads to improved IC₅₀ over mitomycin C.

    Science.gov (United States)

    Zheng, Zhitong; Touve, Mollie; Barnes, Josue; Reich, Norbert; Zhang, Liming

    2014-08-25

    A DNA crosslinking approach, which is distinct but related to the double alkylation by mitomycin C, involving a novel electrophilic spiro-cyclopropane intermediate is hypothesized. Rational design and substantial structural simplification permitted the expedient chemical synthesis and rapid discovery of MTSB-6, a mitomycin C analogue which is twice as potent as mitomycin C against the prostate cancer cells. MTSB-6 shows improvements in its selective action against noncancer prostate cells over mitomycin C. This hypothesis-driven discovery opens novel yet synthetically accessible mitosene structural space for discovering more potent and less toxic therapeutic candidates.

  9. Mobile Probing and Probes

    DEFF Research Database (Denmark)

    2013-01-01

    to mobile probing being a flexible method for uncovering the unknowns, as a way of getting rich data to the analysis and design phases. On the other hand it is difficult to engage users to give in depth explanations, which seem easier in synchronous dialogs (whether online or face2face). The development...

  10. Probing seismic solar analogues through observations with the NASA Kepler space telescope and HERMES high-resolution spectrograph

    CERN Document Server

    Beck, P G; García, R A; Nascimento,, J do; Duarte, T S S; Mathis, S; Regulo, C; Ballot, J; Egeland, R; Castro, M; Pérez-Herńandez, F; Creevey, O; Tkachenko, A; van Reeth, T; Bigot, L; Corsaro, E; Metcalfe, T; Mathur, S; Palle, P L; Prieto, C Allende; Montes, D; Johnston, C; Andersen, M F; van Winckel, H

    2016-01-01

    Stars similar to the Sun, known as solar analogues, provide an excellent opportunity to study the preceding and following evolutionary phases of our host star. The unprecedented quality of photometric data collected by the \\Kepler NASA mission allows us to characterise solar-like stars through asteroseismology and study diagnostics of stellar evolution, such as variation of magnetic activity, rotation and the surface lithium abundance. In this project, presented in a series of papers by Salabert et al. (2016a,b) and Beck et al (2016a,b), we investigate the link between stellar activity, rotation, lithium abundance and oscillations in a group of 18 solar-analogue stars through space photometry, obtained with the NASA Kepler space telescope and from currently 50+ hours of ground-based, high-resolution spectroscopy with the Hermes instrument. In these proceedings, we first discuss the selection of the stars in the sample, observations and calibrations and then summarise the main results of the project. By invest...

  11. Net current measurements and secondary electron emission characteristics of the Voyager plasma science experiment and their impact on data interpretation

    Science.gov (United States)

    Mcnutt, Ralph L., Jr.

    1988-01-01

    The Voyager Plasma Science (PLS) instrument is capable of returning integral (DC) current measurements, similar in some respects to measurements made with a Langmuir probe or a retarding potential analyzer, although there are significant differences. The integral measurements were made during a calibration sequence in the solar wind, during Cruise Science Maneuvers, and within the magnetospheres of Jupiter and Saturn by Voyager 1. After the failure of the PLS experiment following the Saturn encounter, that instrument was placed in the DC return mode returning possibly usable data from early 1981 through early 1985. The DC return measurements are difficult to interpret and are above threshold values only for relatively large fluxes; the determination of the measured current level is dependent on the operating temperature of the preamplifiers which further complicates the interpretation. Nevertheless, these measurements can be used to determine the efficiency of the suppressor grid at preventing the loss of secondary electrons off the collector plate. Some DC return measurements have been invaluable in aiding in the interpretation of some electron plasma measurements not previously understood. It is found that electron spectra can be significantly modified by the presence of second generation secondary electrons produced by either first generation secondaries or photoelectrons on the support ring of the negative high voltage modulator grid within the instrument housing.

  12. Probing Seismic Solar Analogues Through Observations With The NASA Kepler Space Telescope and Hermes High-Resolution Spectrograph

    Science.gov (United States)

    Beck, P. G.; Salabert, D.; Garcia, R. A.; do Nascimento, J., Jr.; Duarte, T. S. S.; Mathis, S.; Regulo, C.; Ballot, J.; Egeland, R.; Castro, M.; Pérez-Herńandez, F.,; Creevey, O.; Tkachenko, A.; van Reeth, T.; Bigot, L.; Corsaro, E.; Metcalfe, T.; Mathur, S.; Palle, P. L.; Allende Prieto, C.; Montes, D.; Johnston, C.; Andersen, M. F.; van Winckel, H.

    2016-11-01

    Stars similar to the Sun, known as solar analogues, provide an excellent opportunity to study the preceding and following evolutionary phases of our host star. The unprecedented quality of photometric data collected by the Kepler NASA mission allows us to characterise solar-like stars through asteroseismology and study diagnostics of stellar evolution, such as variation of magnetic activity, rotation and the surface lithium abundance. In this project, presented in a series of papers by Salabert et al (2016ab) and Beck et al. (2016ab), we investigate the link between stellar activity, rotation, lithium abundance and oscillations in a group of 18 solar-analogue stars through space photometry, obtained with the NASA Kepler space telescope and from currently 50+ hours of ground-based, high-resolution spectroscopy with the Hermes instrument. In these proceedings, we first discuss the selection of the stars in the sample, observations and calibrations and then summarise the main results of the project. By investigating the chromospheric and photospheric activity of the solar analogues in this sample, it was shown that for a large fraction of these stars the measured activity levels are compatible to levels of the 11-year solar activity cycle 23. A clear correlation between the lithium abundance and surface rotation was found for rotation periods shorter than the solar value. Comparing the lithium abundance measured in the solar analogues to evolutionary models with the Toulouse-Geneva Evolutionary Code (TGEC), we found that the solar models calibrated to the Sun also correctly describe the set of solar/stellar analogs showing that they share the same internal mixing physics. Finally, the star KIC3241581 and KIC10644353 are discussed in more detail.

  13. Voyager Interactive Web Interface to EarthScope

    Science.gov (United States)

    Eriksson, S. C.; Meertens, C. M.; Estey, L.; Weingroff, M.; Hamburger, M. W.; Holt, W. E.; Richard, G. A.

    2004-12-01

    Visualization of data is essential in helping scientists and students develop a conceptual understanding of relationships among many complex types of data and keep track of large amounts of information. Developed initially by UNAVCO for study of global-scale geodynamic processes, the Voyager map visualization tools have evolved into interactive, web-based map utilities that can make scientific results accessible to a large number and variety of educators and students as well as the originally targeted scientists. A portal to these map tools can be found at: http://jules.unavco.org. The Voyager tools provide on-line interactive data visualization through pre-determined map regions via a simple HTML/JavaScript interface (for large numbers of students using the tools simultaneously) or through student-selectable areas using a Java interface to a Generic Mapping Tools (GMT) engine. Students can access a variety of maps, satellite images, and geophysical data at a range of spatial scales for the earth and other planets of the solar system. Students can also choose from a variety of base maps (satellite mosaics, global topography, geoid, sea-floor age, strain rate and seismic hazard maps, and others) and can then add a number of geographic and geophysical overlays, for example coastlines, political boundaries, rivers and lakes, earthquake and volcano locations, stress axes, and observed and model plate motion, as well as deformation velocity vectors representing a compilation of over 5000 geodetic measurements from around the world. The related educational website, "Exploring our Dynamic Planet", (http://www.dpc.ucar.edu/VoyagerJr/jvvjrtool.html) incorporates background materials and curricular activities that encourage students to explore Earth processes. One of the present curricular modules is designed for high school students or introductory-level undergraduate non-science majors. The purpose of the module is for students to examine real data to investigate how plate

  14. The Effects of Voyaging on the Magnetization of Ship Models.

    Science.gov (United States)

    1980-05-05

    time-effect must be analyzed for more accurate prediction of voyage effects. Finally, experiments must be conducted with samples of HY80 steel , for...models were tested by subjecting two sample rods, one of HY1O0 steel and one of HY130 steel to an apparatus for supply of cyclic stress of two amplitudes...Entered) WI UNCLASSIFIED I SECURITY CLASSIFICATION Of T"IS PAGE (Whm Da ffIfete 0. 0.CONTIN(UMD steel , and these were compared with the slope of the

  15. Nuclear power in space. Use of reactors and radioactive substances as power sources in satellites and space probes; Kaernkraft i rymden. Anvaendningen av reaktorer och radioaktiva aemnen som kraftkaellor i satelliter och rymdsonder

    Energy Technology Data Exchange (ETDEWEB)

    Hoestbaeck, Lars

    2008-11-15

    Today solar panels are the most common technique to supply power to satellites. Solar panels will work as long as the power demand of the satellite is limited and the satellite can be equipped with enough panels, and kept in an orbit that allows enough sunlight to hit the panels. There are various types of space missions that do not fulfil these criteria. With nuclear power these types of missions can be powered regardless of the sunlight and as early as 1961 the first satellite with a nuclear power source was placed in orbit. Out of seventy known space missions that has made use of nuclear power, ten have had some kind of failure. In no case has the failure been associated with the nuclear technology used. This report discusses to what degree satellites with nuclear power are a source for potential radioactive contamination of Swedish territory. It is not a discussion for or against nuclear power in space. Neither is it an assessment of consequences if radioactive material from a satellite would reach the earth's surface. Historically two different kinds of Nuclear Power Sources (NPS) have been used to generate electric power in space. The first is the reactor where the energy is derived from nuclear fission of 235U and the second is the Radioisotope Thermoelectric Generator (RTG) where electricity is generated from the heat of naturally decaying radionuclides. NPS has historically only been used in space by United States and the Soviet Union (and in one failing operation Russia). Nuclear Power Sources have been used in three types of space objects: satellites, space probes and moon/Mars vehicles. USA has launched one experimental reactor into orbit, all other use of NPS by the USA has been RTG:s. The Soviet Union, in contrast, only launched a few RTG:s but nearly forty reactors. The Soviet use of NPS is less transparent than the use in USA and some data published on Soviet systems are more or less well substantiated assessments. It is likely that also future

  16. 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...

  17. Probing structure and microstructure of epitaxial Ni-Mn-Ga films by reciprocal space mapping and pole figure measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Y., E-mail: yanling.ge@tkk.fi [Aalto University, School of Science and Technology, Department of Materials Science and Engineering, PO Box 16200, FI-00076 Aalto (Finland); Heczko, O. [Institute of Physics, AS CR, Na Slovance 2, CZ-18221 Praha 8 (Czech Republic); Hannula, S.-P. [Aalto University, School of Science and Technology, Department of Materials Science and Engineering, PO Box 16200, FI-00076 Aalto (Finland); Faehler, S. [IFW Dresden, PO Box 270116, 01171 Dresden (Germany)

    2010-12-15

    The crystal structure and complex twinning microstructure of epitaxial Ni-Mn-Ga films on (1 0 0) MgO substrates was studied by X-ray diffraction using 2{theta} scans, pole figure measurements and reciprocal space mapping (RSM). The orientation distribution of all variants is visualized by RSM, which forms the basis for a better understanding of the crystallographic relation between variants and substrate. Above the martensitic transformation temperature the film consists of single austenite phase with lattice constant a = 5.81 A at 419 K. At room temperature some epitaxially grown residual austenite with a = 5.79 A remains at the interface with the substrate, followed by an intermediate layer exhibiting orthorhombic distortion, a{sub trans} = 6.05 A, b{sub trans} = 5.87 A, c{sub trans} = 5.73 A and a major fraction of 14M (7M) martensite, a = 6.16 Ab = 5.79 Ac = 5.48 A. The seven-layered modulation of this metastable martensite structure is directly observed by RSM. The intermediate phase observed close to interface indicates the existence of an instable, pre-adaptive martensite phase with a short stacking period.

  18. On radial heliospheric magnetic fields: Voyager 2 observation and model

    Science.gov (United States)

    Wang, C.; Richardson, J. D.; Burlaga, L. F.; Ness, N. F.

    2003-05-01

    The heliospheric magnetic field (HMF) direction, on average, conforms well to the Parker spiral. However, numerous examples of events where the HMF is oriented in near-radial directions for many hours have been reported on the basis of observations inside 5 AU from spacecraft such as ISEE-3 and Ulysses. The magnetic field data observed by Voyager 2 from launch in 1977 through the end of 1982 (i.e., between 1 and ˜10 AU) were searched for all instances of radial fields with durations of 6 hours or more. Radial fields of significant durations at large distances are unusual as the Parker spiral is very tightly wound. The radial HMF events in the inner heliosphere typically occur at times when the solar wind speed is declining gradually, while they tend to be associated with steady wind speeds at distances beyond ˜6 AU. The durations of these events appear to be independent of distance and solar cycle, with an average duration of ˜11 hours. They generally are not associated with interplanetary coronal mass ejections (ICMEs). Possible generation mechanisms of the radial field events related to speed variations near the Sun are investigated by use of a MHD model. We find that a noticeable low-speed plateau of limited duration in solar wind speed near the Sun can produce radial field events having durations of the order of 10 hours in the heliosphere as observed by Voyager 2.

  19. MULTIFRACTAL STRUCTURES DETECTED BY VOYAGER 1 AT THE HELIOSPHERIC BOUNDARIES

    Energy Technology Data Exchange (ETDEWEB)

    Macek, W. M. [Faculty of Mathematics and Natural Sciences, Cardinal Stefan Wyszyński University, Wóycickiego 1/3, 01-938 Warsaw (Poland); Wawrzaszek, A. [Space Research Centre, Polish Academy of Sciences, Bartycka 18 A, 00-716 Warszawa (Poland); Burlaga, L. F., E-mail: macek@cbk.waw.pl, E-mail: anna.wawrzaszek@cbk.waw.pl, E-mail: lburlagahsp@verizon.net [NASA Goddard Space Flight Center, Code 673, Greenbelt, MD 20771 (United States)

    2014-10-01

    To better understand the dynamics of turbulent systems, we have proposed a phenomenological model based on a generalized Cantor set with two rescaling and one weight parameters. In this Letter, using recent Voyager 1 magnetic field data, we extend our two-scale multifractal analysis further in the heliosheath beyond the heliospheric termination shock, and even now near the heliopause, when entering the interstellar medium for the first time in human history. We have identified the scaling inertial region for magnetized heliospheric plasma between the termination shock and the heliopause. We also show that the degree of multifractality decreases with the heliocentric distance and is still modulated by the phases of the solar cycle in the entire heliosphere including the heliosheath. Moreover, we observe the change of scaling toward a nonintermittent (nonmultifractal) behavior in the nearby interstellar medium, just beyond the heliopause. We argue that this loss of multifractal behavior could be a signature of the expected crossing of the heliopause by Voyager 2 in the near future. The results obtained demonstrate that our phenomenological multifractal model exhibits some properties of intermittent turbulence in the solar system plasmas, and we hope that it could shed light on universal characteristics of turbulence.

  20. Shared Voyage: Learning and Unlearning from Remarkable Projects

    Science.gov (United States)

    Laufer, Alexander; Post, Todd; Hoffman, Edward J.

    2005-01-01

    Shared Voyage is about four remarkable projects: the Advanced Composition Explorer (NASA), the Joint Air-to-Surface Standoff Missile (U.S. Air Force), the Pathfinder Solar-Powered Airplane (NASA), and the Advanced Medium Range Air-to-Air Missile (U.S.Air Force). Each project is presented as a case study comprised of stories collected from key members of the project teams. The stories found in the book are included with the purpose of providing an effective learning source for project management, encouraging the unlearning of outdated project management concepts, and enhancing awareness of the contexts surrounding different projects. Significantly different from project concepts found in most project management literature, Shared Voyage highlights concepts like a will to win, a results-oriented focus, and collaboration through trust. All four project teams researched in this study applied similar concepts; however, they applied them differently, tailoring them to fit the context of their own particular projects. It is clear that the one best way approach which is still the prevailing paradigm in project management literature should be replaced by a new paradigm: Even though general project management principles exist, their successful application depends on the specifics of the situation.

  1. Io Plasma Torus Ion Composition: Voyager, Galileo, Cassini

    Science.gov (United States)

    Bagenal, Fran; Nerney, Edward; Steffl, Andrew Joseph

    2016-10-01

    With JAXA's Hisaki spacecraft in orbit around Earth gathering information on the Io plasma torus and NASA's Juno mission measuring plasma conditions in the jovian magnetosphere, the time is ripe for a re-evaluation of earlier observations of the plasma torus to assess evidence for temporal variations. In particular, we are interested in exploring the ion composition of the torus and whether there is evidence of the ultimate source – the volcanic gases from Io – have deviated from SO2. We use the latest CHIANTI 8.0 atomic database to analyze UV spectra of the torus from Voyager, Galileo and Cassini as well as with the physical chemistry model of Delamere, Steffl and Bagenal (2005). We find that contrary to earlier analyses of Voyager data (e.g. Shemansky 1987; 1988) that produced a composition requiring a neutral source of O/S~4, we find an ion composition that is consistent with the Cassini UVIS data (Steffl et al. 2004) and a neutral O/S~2, consistent with SO2.

  2. Interstellar Mapping and Acceleration Probe (IMAP)

    Science.gov (United States)

    Schwadron, Nathan

    2016-04-01

    Our piece of cosmic real-estate, the heliosphere, is the domain of all human existence - an astrophysical case-history of the successful evolution of life in a habitable system. By exploring our global heliosphere and its myriad interactions, we develop key physical knowledge of the interstellar interactions that influence exoplanetary habitability as well as the distant history and destiny of our solar system and world. IBEX was the first mission to explore the global heliosphere and in concert with Voyager 1 and Voyager 2 is discovering a fundamentally new and uncharted physical domain of the outer heliosphere. In parallel, Cassini/INCA maps the global heliosphere at energies (~5-55 KeV) above those measured by IBEX. The enigmatic IBEX ribbon and the INCA belt were unanticipated discoveries demonstrating that much of what we know or think we understand about the outer heliosphere needs to be revised. The next quantum leap enabled by IMAP will open new windows on the frontier of Heliophysics at a time when the space environment is rapidly evolving. IMAP with 100 times the combined resolution and sensitivity of IBEX and INCA will discover the substructure of the IBEX ribbon and will reveal in unprecedented resolution global maps of our heliosphere. The remarkable synergy between IMAP, Voyager 1 and Voyager 2 will remain for at least the next decade as Voyager 1 pushes further into the interstellar domain and Voyager 2 moves through the heliosheath. The "A" in IMAP refers to acceleration of energetic particles. With its combination of highly sensitive pickup and suprathermal ion sensors, IMAP will provide the species and spectral coverage as well as unprecedented temporal resolution to associate emerging suprathermal tails with interplanetary structures and discover underlying physical acceleration processes. These key measurements will provide what has been a critical missing piece of suprathermal seed particles in our understanding of particle acceleration to high

  3. Upper Limits on O VI Emission from Voyager Observations

    Indian Academy of Sciences (India)

    Jayant Murthy

    2002-03-01

    We have examined 426 Voyager fields distributed across the sky for O VI ( 1032/1038 Å) emission from the Galactic diffuse interstellar medium. No such emission was detected in any of our observed fields. Our most constraining limit was a 90% confidence upper limit of 2600 photons cm-2 sr-1 s-1 on the doublet emission in the direction (l, b) = (117.3, 50.6). Combining this with an absorption line measurement in nearly the same direction allows us to place an upper limit of 0.01 cm-3 on the electron density of the hot gas in this direction. We have placed 90% confidence upper limits of less than or equal to 10,000 photons cm-2 sr-1 s-1 on the O VI emission in 16 of our 426 observations.

  4. Active Probing of Space Plasmas

    Science.gov (United States)

    1989-09-01

    corroborate the &*skty 111"- or a very negatively charged body. In previous publica . 1la Wolene af Ot presac o m Ornbaemn farW~ beW h IOMt ad #k tions...have evolved into periodic spikes. The middle and botcom panels of Figura 4 represent the nor- malized energetic particle density (cm- 2 ) cona.ined on

  5. Has the Sun Significantly Impacted Recent Voyager Observations?

    Science.gov (United States)

    Intriligator, D. S.; Sun, W.; Detman, T. R.; Dryer, Ph. D., M.; Deehr, C. S.; Intriligator, J.; Webber, W. R.

    2013-12-01

    Using our models HAFSS (HAF Source Surface) and HHMS-PI (Hybrid Heliospheric Modeling System with Pickup Protons) we have been analyzing some of the recent (e.g., July 2012, etc.) solar events to determine if the effects of the events might be seen in the outer heliosphere, heliosheath, etc. Our analyses provide insights into the phenomena in these regions. Both models are three-dimensional (3D) time dependent simulations that use solar observations as input. HAFSS is a kinematic model. HHMS-PI is a numerical magnetohydrodynamic solar wind (SW) simulation model. Both HHMS-PI and HAFSS are ideally suited for these analyses since starting from the Sun they model the slowly evolving background SW and the impulsive, time-dependent events associated with solar activity (e.g., coronal mass ejections (CMEs). HHMS-PI/HAFSS make it possible to track interplanetary shocks as they propagate, interact, and evolve en route to various spacecraft (s/c) where they are observed. Our models have been used to reproduce s/c data from ACE to Ulysses, Cassini, and Voyagers 1 and 2. Our published results in refereed scientific journals showed that: a.) Our models naturally reproduce dynamic 3D spatially asymmetric effects observed throughout the heliosphere. b.) Pre-existing SW background conditions have a strong influence on the propagation of shock waves from solar events. c.) Time-dependence is a crucial aspect of interpreting s/c data. d.) Shock interactions resulting from multiple solar events lead to complicated time-series observations at individual s/c. We believe the answer to the question in the title of this abstract is: Yes, we do think the Sun has significantly impacted recent Voyager observations.

  6. Monitor and Control of the Deep-Space network via Secure Web

    Science.gov (United States)

    Lamarra, N.

    1997-01-01

    (view graph) NASA lead center for robotic space exploration. Operating division of Caltech/Jet Propulsion Laboratory. Current missions, Voyagers, Galileo, Pathfinder, Global Surveyor. Upcoming missions, Cassini, Mars and New Millennium.

  7. Pioneer and Voyager observations of the solar wind at large heliocentric distances and latitudes

    Science.gov (United States)

    Gazis, P. R.; Mihalov, J. D.; Barnes, A.; Lazarus, A. J.; Smith, E. J.

    1989-01-01

    Data obtained from the electrostatic analyzers aboard the Pioneer 10 and 11 spacecraft and from the Faraday cup aboard Voyager 2 were used to study spatial gradients in the distant solar wind. Prior to mid-1985, both spacecraft observed nearly identical solar wind structures. After day 150 of 1985, the velocity structure at Voyager 2 became flatter, and the Voyager 2 velocities were smaller than those observed by Pioneer 11. It is suggested that these changes in the solar wind at low latitudes may be related to a change which occurred in the coronal hole structure in early 1985.

  8. Spaces

    Directory of Open Access Journals (Sweden)

    Maziar Nekovee

    2010-01-01

    Full Text Available Cognitive radio is being intensively researched as the enabling technology for license-exempt access to the so-called TV White Spaces (TVWS, large portions of spectrum in the UHF/VHF bands which become available on a geographical basis after digital switchover. Both in the US, and more recently, in the UK the regulators have given conditional endorsement to this new mode of access. This paper reviews the state-of-the-art in technology, regulation, and standardisation of cognitive access to TVWS. It examines the spectrum opportunity and commercial use cases associated with this form of secondary access.

  9. Radioisotope Power: A Key Technology for Deep Space Explorations

    Science.gov (United States)

    Schmidt, George R.; Sutliff, Thomas J.; Duddzinski, Leonard

    2009-01-01

    A Radioisotope Power System (RPS) generates power by converting the heat released from the nuclear decay of radioactive isotopes, such as Plutonium-238 (Pu-238), into electricity. First used in space by the U.S. in 1961, these devices have enabled some of the most challenging and exciting space missions in history, including the Pioneer and Voyager probes to the outer solar system; the Apollo lunar surface experiments; the Viking landers; the Ulysses polar orbital mission about the Sun; the Galileo mission to Jupiter; the Cassini mission orbiting Saturn; and the recently launched New Horizons mission to Pluto. Radioisotopes have also served as a versatile heat source for moderating equipment thermal environments on these and many other missions, including the Mars exploration rovers, Spirit and Opportunity. The key advantage of RPS is its ability to operate continuously, independent of orientation and distance relative to the Sun. Radioisotope systems are long-lived, rugged, compact, highly reliable, and relatively insensitive to radiation and other environmental effects. As such, they are ideally suited for missions involving long-lived, autonomous operations in the extreme conditions of space and other planetary bodies. This paper reviews the history of RPS for the U.S. space program. It also describes current development of a new Stirling cycle-based generator that will greatly expand the application of nuclear-powered missions in the future.

  10. A voyage to the country of the Houyhnhnms : ironia e arte satírica

    OpenAIRE

    Homem, Rui Carvalho

    2014-01-01

    The author tries to account for the controversy surrounding the fourth Voyage in Swift's Gulliver's Travels, by pointing out the clash between the consequences of sustained irony and the demands of satire, and its expression in specific narrative strategies.

  11. Recent Voyager Evidence for Rapid Transport of Flare-Generated Disturbances by Polar Coronal Hole Streams

    Science.gov (United States)

    Intriligator, D. S.; Miller, W. D.; Intriligator, J.; Webber, W.; Sun, W.; Detman, T.; Dryer, M.; Deehr, C.

    2017-09-01

    Disturbances observed by Voyagers 1 and 2 during the past five years or more may have been transported by plasma emitted from polar coronal holes, thereby having travelled much faster from the Sun to the termination shock than previously recognized. Estimating the average speed to the shock as 750 km/s has produced consistently good associations between solar flares, or groups of them, and dynamic pressure increases at Voyager 2 and plasma wave events at Voyager 1. Furthermore, magnetograph observations confirm that polar coronal holes were present around the times of the flares to which the events at the Voyagers have been attributed. These calculations also provide revised estimates of the transport of heliospheric current sheet fluctuations. We discuss the possibilities that extrapolations from past observations and simulations based on them may provide insight into currently challenging issues and possible future developments.

  12. Voyager 1 observes low-energy galactic cosmic rays in a region depleted of heliospheric ions

    National Research Council Canada - National Science Library

    Stone, E C; Cummings, A C; McDonald, F B; Heikkila, B C; Lal, N; Webber, W R

    2013-01-01

    On 25 August 2012, Voyager 1 was at 122 astronomical units when the steady intensity of low-energy ions it had observed for the previous 6 years suddenly dropped for a third time and soon completely...

  13. Synthetic Micro/Nanomachines and Their Applications: Towards 'Fantastic Voyage'

    Science.gov (United States)

    Gao, Wei

    The 1966 movie Fantastic Voyage captured the world's imagination, portraying a tiny submarine navigating through the human bloodstream and treating life-threatening medical conditions. My PhD research focuses on the synthetic nano/microscale machines to realize the Fantastic Voyage vision. Various biomedical and environmental areas would benefit from the developments of efficient fuel-free and fuel-driven nano/microscale machines. The polymer-based catalytic tubular microengine is synthesized using a template based electrodeposition method. The oxygen bubble propelled microengine harvests the energy from chemical fuels (such as H2O2) and displays very efficient propulsion. It can serve as an ideal platform for diverse biomedical and environmental applications. For example, lectin modified polyaniline based microengines can be used for selective bacteria (E. Coli) isolation from food, clinical and environmental samples; poly(3-aminophenylboronic acid)/Ni/Pt microengine itself provides the 'built in' glucose recognition capability for 'on-the-fly' capture, transport and release of yeast cells. A series of micromotors which can be self-propelled in natural environments without additional chemical fuels are developed, holding great promise for in vivo biomedical applications: the polyaniline/zinc microrockets display effective autonomous motion in extreme acidic environments (such as human stomach); the Al-Ga/Ti based Janus micromotor can be propelled by the hydrogen bubbles generated from the rapid aluminum and water reaction; alkanethiols modified seawater-driven Mg Janus micromotors, which utilize macrogalvanic corrosion and chloride pitting corrosion processes, can be used for environmental oil remediation. Magnetically powered nanoswimmers have attracted considerable attention due to their great biocompatibility. A high-speed magnetically-propelled nanowire swimmer which mimics swimming microorganisms by exploiting the flexible nanowire as artificial flagella

  14. Small Probe Reentry System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Aerospace Corporation (GAC), and its research partner, Cal Poly San Luis Obispo (CPSLO), will develop an integrated Small Probe Reentry System (SPRS) for low...

  15. Probe Storage

    NARCIS (Netherlands)

    Gemelli, Marcellino; Abelmann, Leon; Engelen, Johan B.C.; Khatib, Mohammed G.; Koelmans, Wabe W.; Zaboronski, Olog; Campardo, Giovanni; Tiziani, Federico; Laculo, Massimo

    2011-01-01

    This chapter gives an overview of probe-based data storage research over the last three decades, encompassing all aspects of a probe recording system. Following the division found in all mechanically addressed storage systems, the different subsystems (media, read/write heads, positioning, data chan

  16. Cultural probes

    DEFF Research Database (Denmark)

    Madsen, Jacob Østergaard

    2016-01-01

    The aim of this study was thus to explore cultural probes (Gaver, Boucher et al. 2004), as a possible methodical approach, supporting knowledge production on situated and contextual aspects of occupation.......The aim of this study was thus to explore cultural probes (Gaver, Boucher et al. 2004), as a possible methodical approach, supporting knowledge production on situated and contextual aspects of occupation....

  17. The PTSD supremacy: Criterion F in three Voyager cases.

    Science.gov (United States)

    Gaughwin, Peter

    2009-04-01

    The aim is to consider whether the courts and experts in their application of Criterion F for posttraumatic stress disorder (PTSD) have applied it consistently in civil claims brought years after the event. Three cases for compensation relating to the Voyager disaster are considered. It appears, from the cases considered in this paper, that while courts consider that Criterion F is crucial in making a diagnosis of PTSD, there are some inconsistencies in terms of understanding and applying this criterion, both by the courts and experts. This may be because of a lack of guidance in psychiatric texts as to how to apply Criterion F. Criterion F is, after the satisfaction of Criterion A(1), arguably the most important of the criteria for PTSD for, while the symptoms referred to in Criteria B-D have been shown to be fairly easy to simulate, it is arguably harder to do this with Criterion F, particularly in cases that arise a long time after the event. It is important therefore that psychiatrists assessing persons so long after an event adhere rigorously to Criterion F, because it is based on facts open to objective corroboration, while criteria B, C and D tend to rely on subjective experiences which are the most sensitive to distortion. Thus, it is to be hoped that if DSM-V is to maintain a criterion of clinically significant distress or impairment in the majority of the disorders described therein, it will provide some assistance as to how this criteria should be applied.

  18. Current Sheets in the Heliosheath: Voyager 1, 2009

    Science.gov (United States)

    Burlaga, L. F.; Ness, N. F.

    2011-01-01

    We identified all of the current sheets for which we have relatively complete and accurate magnetic field (B) data from Voyager 1 (V1) from days of year (DOYs) 1 to 331, 2009, which were obtained deep in the heliosheath between 108.5 and 111.8 AU. Three types of current sheets were found: (1) 15 proton boundary layers (PBLs), (2) 10 and 3 magnetic holes and magnetic humps, respectively, and (3) 3 sector boundaries. The magnetic field strength changes across PBL, and the profile B(t) is linearly related to the hyperbolic tangent function, but the direction of B does not change. For each of the three sector boundaries, B rotated in a plane normal to the minimum variance direction, and the component of B along the minimum variance direction was zero within the uncertainties, indicating that the sector boundaries were tangential discontinuities. The structure of the sector boundaries was not as simple as that for PBLs. The average thickness of magnetic holes and humps (approx.30 RL) was twice that of the PBLs (approx.15 RL). The average thickness of the current sheets associated with sector boundaries was close to the thickness of the PBLs. Our observations are consistent with the hypothesis that magnetic holes and humps are solitons, which are initiated by the mirror mode instability, and evolve by nonlinear kinetic plasma processes to pressure balanced structures maintained by magnetization currents and proton drift currents in the gradients of B.

  19. Developing Virtual CD-ROM Collections: The Voyager Company Publications

    Directory of Open Access Journals (Sweden)

    Geoffrey Brown

    2012-12-01

    Full Text Available Over the past 20 years, many thousands of CD-ROM titles were published; many of these have lasting cultural significance, yet present a difficult challenge for libraries due to obsolescence of the supporting software and hardware, and the consequent decline in the technical knowledge required to support them. The current trend appears to be one of abandonment – for example, the Indiana University Libraries no longer maintain machines capable of accessing early CD-ROM titles.In previous work, we proposed an access model based upon networked ‘virtual collections’ of CD-ROMs which can enable consortia of libraries to pool the technical expertise necessary to provide continued access to such materials for a geographically sparse base of patrons, who may have limited technical knowledge.In this paper, we extend this idea to CD-ROMs designed to operate on ‘classic’ Macintosh systems with an extensive case study – the catalog of the Voyager Company publications, which was the first major innovator in interactive CD-ROMs. The work described includes emulator extensions to support obsolete CD formats and to enable networked access to the virtual collection.

  20. The helium abundance of Uranus from Voyager measurements

    Science.gov (United States)

    Conrath, B.; Hanel, R.; Gautier, D.; Marten, A.; Lindal, G.

    1987-12-01

    Voyager radio-occultation and IR spectroscopy measurements are combined to infer an He mole fraction in the upper troposphere of Uranus of 0.152 + or - 0.033; the corresponding mass fraction is Y = 0.262 + or - 0.048. This value is in agreement with recent estimates of the solar He abundance, suggesting that He differentiation has not occurred on Uranus. Comparisons with values previously obtained for Jupiter and Saturn imply that migration of He toward the core began long ago on Saturn and may also have recently begun on Jupiter. The protosolar He abundance inferred from the Uranus measurements and from recent solar evolutionary models is used along with an assumed primordial He mass fraction of 0.23-0.24 to estimate a 3-4-percent enrichment of He in the interstellar medium between the big bang and the origin of the solar system. The result is in agreement with galactic chemical evolution models which include a substantial decrease in D during the evolutionary process.

  1. Positioning Reduction of Deep Space Probes Based on VLBI Tracking%深空探测器VLBI跟踪定位归算

    Institute of Scientific and Technical Information of China (English)

    乔书波

    2011-01-01

    . (2) Develop software modules for the correction of various observational errors related to the transmis-sion medium, quasi-clock bias and gravitational retardation, in particular, the correction of the quasi-clock uncertainty based on observations of extragalactic radio sources with known coordinates, for the enhancement of the systematicness and integrity of the current soft-ware. (3) Improve the function of the existing software on the reduction of observations of differential, phase referencing and same beam VLBI with simulation and real data tests. (4) Investigate the application of Kalman filter to the positioning reduction of deep space probes and develop related software systems.In summary, the progress in this dissertation is made in the positioning reduction of deep space probes tracked by VLBI concerning the algorithm study, software development, real observation processing and so on, while a further study is still urgent and arduous.

  2. Man in space: A new dimension in Health Care

    Directory of Open Access Journals (Sweden)

    L. Medlen

    1983-09-01

    Full Text Available Unprecedented advances in technology and science in the 20th Century have enabled man to take himself and his inventions on voyages of space exploration. It has been man's dream for centuries, not only to fly, but also to explore the vast outer reaches of space. Modern space exploration, the new frontier, is a triumph for the new sciences of space biology and space medicine.

  3. [Sun Simiao's voyage to Chu and Shu regions].

    Science.gov (United States)

    Song, Zhenmin

    2014-07-01

    During the 4(th)-11(th) years of Zhenguan reign of the Tang Dynasty, Sun Simiao paid a voyage to the regions of Chu (now mostly the Hubei Province) and Shu (now Sichuan Province) for a total of 14 years. In the 4(th) year of Zhenguan, he went to treat the "hydropsy" of Li Gui, the King of Hanyang, hence, the record given as the 9(th) year of Zhenguan by Bei ji qian jin yao fang (Essential Prescriptions for Emergency Worth a Thousand Gold) is not correct. Later, he went to Jiangzhou (now Jiujiang city of Jiangxi Province) to treat Chen Shuping's, the King of Chenxiangdong beriberi due to wind-poisoning. In the 15(th) of July, the 5(th) year of Zhenguan, he himself suffered a swelling pain in his finger when travelling in Shu region, due to a poisonous sting, which was cured by rubbing with the juice from the root and stem of dendelion. In the 7(th) year of Zhenguan, he suffered a facial erysipelas due to over drinking when he was in Neijiang County which was treated by the mayor, Master Li, with various medications to no avail, which was eventually cured by himself. In the 10(th) year of Zhenguan, he treated the Governor of Zizhou Li Wenbo's consuming thirst. He also got a large amount of copper salts in the Counties of Xuanwu and Feiwu nearby. In the 17(th) year of Zhenguan or later, he processed the "Tai yi spiritual powder" in Wei's family of Shu County. After finishing the processing, he returned to Guanzhong (now Shaanxi) at certain period of "August of 17(th) year of Zhenguan", "January of 18(th) year of Zhenguan", or "January of 19(th) year of Zhenguan".

  4. EVIDENCE FOR A SHOCK IN INTERSTELLAR PLASMA: VOYAGER 1

    Energy Technology Data Exchange (ETDEWEB)

    Burlaga, L. F. [NASA Goddard Space Flight Center, Code 673, Greenbelt, MD 20771 (United States); Ness, N. F. [Institute for Astrophysics and Computational Sciences, Catholic University of America, Washington, DC 20064 (United States); Gurnett, D. A.; Kurth, W. S., E-mail: lburlagahsp@verizon.net, E-mail: nfnudel@yahoo.com, E-mail: donald-gurnett@uiowa.edu, E-mail: william-kurth@uiowa.edu [University of Iowa, Iowa City, IA 52242 (United States)

    2013-11-20

    Voyager 1 (V1) observed electron plasma oscillations preceding a jump by a factor of 1.4 in the magnetic field intensity B near the end of 2012. The frequency of the electron plasma oscillations gives an electron density n{sub e}  = 0.05 cm{sup –3}, which implies that V1 was immersed in plasma from the interstellar medium. The last day on which plasma oscillations were observed is day 332, 2012, and the jump in the B was centered on day 335, 2012 after a data gap in the wave data. The close association between the electron plasma oscillations and the jump in B suggests a causal connection, such as that frequently observed between electron plasma oscillations and interplanetary shocks at 1 AU. Based on the observed parameters and the smooth profile of B(t), the jump in B appears to be associated with a weak, subcritical, laminar, low beta, quasi-perpendicular, resistive, collisionless shock. However, the width of the jump is of the order of 10{sup 4} times that expected for such a stationary shock at 1 AU. The large width of the jump in B might be the result of differences between the structure of shocks in the interstellar medium and the plasma near 1 AU. Alternatively, the subcritical resistive shock might have decayed during a few days after producing the plasma waves, leaving a broad profile in B(t) without significantly changing ambient parameters. Another possibility is that the jump in B is a pressure wave.

  5. 基于深空探测器下行信号的太阳风观测及通信链路的影响综述∗%A Review of Observations of Solar Winds and Solar Impact on Deep-Space Telecommunications Using Downlink Signals From Space Probes

    Institute of Scientific and Technical Information of China (English)

    唐云秋; 孔德庆

    2015-01-01

    Deep-space telecommunications will be severely affected by solar winds and the solar corona during a Superior Solar Conjunction. In this paper we discuss effects of inhomogeneous solar winds on signals in deep-space telecommunications. The effects include intensity scintillations, phase scintillations, and spectral-broadening phenomena. We then give a comprehensive review of observations of signal scintillations induced by solar winds and solar coronal events using downlink signals from deep-space probes. Our review is based on our investigation of dozens of papers related to the subject. We propose a scheme to observe signal scintillations using communication signals of existing space probes. The scheme aims to advance the Chinese deep-space exploration plan. The scheme can be applied in conjunction with data communications and orbital measurements of deep-space probes once the Chinese deep-space exploration starts.%在上合期间,日冕和太阳风严重影响深空通信链路。论述了非均匀太阳风对深空通信的影响,综述了基于深空探测器下行信号的太阳风观测,以及通过反演技术进行太阳风和日冕特性研究的国内外进展。以我国的深空探测为背景,提出一套基于探测器下行信号的太阳风观测方案,并可利用现有探测器进行预先观测研究。在我国深空探测任务开始后,在数据通信和测轨的同时,进行全过程的观测实验。

  6. Climate windows for Polynesian voyaging to New Zealand and Easter Island.

    Science.gov (United States)

    Goodwin, Ian D; Browning, Stuart A; Anderson, Atholl J

    2014-10-14

    Debate about initial human migration across the immense area of East Polynesia has focused upon seafaring technology, both of navigation and canoe capabilities, while temporal variation in sailing conditions, notably through climate change, has received less attention. One model of Polynesian voyaging observes that as tradewind easterlies are currently dominant in the central Pacific, prehistoric colonization canoes voyaging eastward to and through central East Polynesia (CEP: Society, Tuamotu, Marquesas, Gambier, Southern Cook, and Austral Islands) and to Easter Island probably had a windward capacity. Similar arguments have been applied to voyaging from CEP to New Zealand against prevailing westerlies. An alternative view is that migration required reliable off-wind sailing routes. We investigate the marine climate and potential voyaging routes during the Medieval Climate Anomaly (MCA), A.D. 800-1300, when the initial colonization of CEP and New Zealand occurred. Paleoclimate data assimilation is used to reconstruct Pacific sea level pressure and wind field patterns at bidecadal resolution during the MCA. We argue here that changing wind field patterns associated with the MCA provided conditions in which voyaging to and from the most isolated East Polynesian islands, New Zealand, and Easter Island was readily possible by off-wind sailing. The intensification and poleward expansion of the Pacific subtropical anticyclone culminating in A.D. 1140-1260 opened an anomalous climate window for off-wind sailing routes to New Zealand from the Southern Austral Islands, the Southern Cook Islands, and Tonga/Fiji Islands.

  7. Climate Voyager: An Iteratively Built Information and Visualization Tool for At-Risk Climate Communities

    Science.gov (United States)

    Terando, A. J.; Lascurain, A.; Aldridge, H. D.; Davis, C.

    2016-12-01

    Climate Voyager provides an innovative way to visualize both large-scale and local climate change projections using a three-map layout and time series plot. This product includes a suite of tools designed to assist with climate risk and opportunity assessments, including changes in average seasonal conditions and the capability to evaluate a variety of different decision-relevant thresholds (e.g. changes in extreme temperature occurrence). Each tool summarizes output from 20 downscaled global climate models and contains a historical average for comparison with the spread of projected future outcomes. The Climate Voyager website is interactive, allowing users to explore both regional and location-specific guidance for two Representative Concentration Pathways (RCPs) and four future 20-year time periods. By presenting climate model projections and measures of uncertainty of specific parameters beyond just annual temperatures and precipitation, Climate Voyager can help a wide variety of decision makers plan for climate changes that may affect them. We present a case study in which a new module was developed within Climate Voyager for use by Tribes and native communities in the eastern U.S. to help make informed resource decisions. In this first attempt, Ramps (Allium tricoccum), a plant species of great cultural significance, was incorporated through consultation with the tribal organization. We will also discuss the process of engagement employed with end-users and the potential to make the Climate Voyager interface an iterative, co-produced process to enhance the usability of climate model information for adaptation planning.

  8. Mobile probes

    DEFF Research Database (Denmark)

    2016-01-01

    A project investigating the effectiveness of a collection of online resources for teachers' professional development used mobile probes as a data collection method. Teachers received questions and tasks on their mobile in a dialogic manner while in their everyday context as opposed to in an inter......A project investigating the effectiveness of a collection of online resources for teachers' professional development used mobile probes as a data collection method. Teachers received questions and tasks on their mobile in a dialogic manner while in their everyday context as opposed...... to in an interview. This method provided valuable insight into the contextual use, i.e. how did the online resource transfer to the work practice. However, the research team also found that mobile probes may provide the scaffolding necessary for individual and peer learning at a very local (intra-school) community...... level. This paper is an initial investigation of how the mobile probes process proved to engage teachers in their efforts to improve teaching. It also highlights some of the barriers emerging when applying mobile probes as a scaffold for learning....

  9. SkyServer Voyages Website - Using Big Data to Explore Astronomy Concepts in Formal Education Settings

    Science.gov (United States)

    Meredith, Kate K.; Masters, Karen; Raddick, Jordan; Lundgren, Britt

    2015-08-01

    The Sloan Digital Sky Survey (SDSS) web interface “SkyServer” has long included online educational materials designed to help students and the public discover the fundamentals of modern astronomy using real observations from the SDSS database. The newly launched SDSS Voyages website updates and expands these activities to reflect new data from subsequent generations of the survey, advances in web technology, and evolving practices in science education. Voyages provides access to quality astronomy, astrophysics, and engineering materials to educators seeking an inquiry approach to fundamental concepts. During this session we will provide an overview of the design and development of Skyserver Voyages and discuss ways to apply this resource at K-12 and university levels.

  10. Study of photoemission and work function of large surface areas, phase 3, phase 4. [wavelength dependences of photoelectric space probe materials

    Science.gov (United States)

    1973-01-01

    The photoemission of materials which might be used in probe measurements of the exo-atmospheric electric field is considered by evaluating the wavelength dependence of their photoelectric yield for eleven elements over the range 800 to 3200 A. Yield data for zinc, copper beryllium, platinum, cadmium, graphite, carbon, gold, silver, tantalum, and tungsten show that copper-beryllium is a preferred material. Silver has one of the highest photoemissions when exposed to solar radiation.

  11. Phoenix Conductivity Probe

    Science.gov (United States)

    2008-01-01

    This image taken by the Surface Stereo Imager on Sol 49, or the 49th Martian day of the mission (July 14, 2008), shows thermal and electrical conductivity probe on NASA's Phoenix Mars Lander's Robotic Arm. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  12. The Plasma Depletion Layer Beyond the Heliopause: Evidence, Implications, and Predictions for Voyager 2

    Science.gov (United States)

    Cairns, I. H.; Fuselier, S. A.

    2015-12-01

    A plasma depletion layer (PDL) is predicted beyond the heliopause, analogous to the PDLs observed sunwards of the magnetopauses of Earth, Mercury, Jupiter, and Saturn. The physics is that draping of interstellar (ISM) magnetic field lines over the heliopause should increase the magnetic field strength (and so the perpendicular ion temperature), cause density depletions by allowing plasma ions (and electrons) with large parallel temperatures to escape along the field, and increase the perpendicular to parallel temperature anisotropy until limited by wave instabilities. It is argued that published Voyager 1 magnetometer and plasma wave data beyond the heliopause provide strong evidence for the magnetic field amplification (by ≈ 30%) and density depletion (by ≈ 50%) expected for the PDL. The predicted reduction in parallel temperature is ≈ 50%. Using the ISM magnetic field direction obtained from the centroid of the IBEX Ribbon, the orientation of the PDL and the associated locations on the heliopause of the points of maximum magnetic field draping and maximum total pressure are predicted. It is observed that the IBEX Ribbon overlies the former while the latter lies within the ridge of maximum non-Ribbon ENA flux. The PDL should be strongest along the ISM field line passing through these points and the nominal Sun-ISM velocity vector. It is predicted that Voyager 2 lies within 5 degrees (≈ 10 AU) of the strong PDL region while Voyager 1 is over 15 degrees (≈ 35 AU) away. Thus Voyager 2 should observe a much stronger PDL (stronger magnetic field amplification, density depletions, and reductions in parallel temperature) than Voyager 1. Finally, the reduced cosmic ray fluxes observed near 90 degree pitchangle by Voyager 1 beyond the heliopause may be explained qualitatively in terms of magnetic focusing as cosmic rays propagate away from the stronger field regions of the PDL and magnetic draping region on the heliopause, assuming isotropic cosmic rays at the

  13. INTERSTELLAR MAGNETIC FIELDS OBSERVED BY VOYAGER 1 BEYOND THE HELIOPAUSE

    Energy Technology Data Exchange (ETDEWEB)

    Burlaga, L. F. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Ness, N. F., E-mail: lburlagahsp@verizon.net, E-mail: nfnudel@yahoo.com [Institute for Astrophysics and Computational Sciences, Catholic University of America, Washington, DC 20064 (United States)

    2014-11-01

    Voyager 1 (V1) was beyond the heliopause between 2013.00 and 2014.41, where it was making in situ observations of the interstellar magnetic field (ISMF). The average azimuthal angle and elevation angle of the magnetic field B were (λ) = 292.°5 ± 1.°4 and (δ) = 22.°1 ± 1.°2, respectively. The angles λ and δ varied linearly at (1.°4 ± 0.°1) yr{sup –1} and (–1.°1 ± 0.°1) yr{sup –1}, respectively, suggesting that V1 was measuring the draped ISMF around the heliopause. The distributions of hourly averages of λ and δ were Gaussian distributions, with most probable values 292.°5 and 22.°1, and standard deviations (SDs) 1.°3 and 1.°1, respectively. The small SD indicates little or no turbulence transverse to B . An abrupt decrease in B from 0.50 nT on 2013/129.9 to 0.46 nT on 2013/130.6 was observed, possibly associated with a weak reverse shock or magnetoacoustic pressure wave following a burst of electron plasma oscillations. Between 2013/130.6 and 2013/365.3, (B) = 0.464 ± 0.009 nT, (λ) = 292.°6 ± 0.°8, and (δ) = 22.°1 ± 1.°1. The corresponding distribution of hourly averages of B was Gaussian with the most probable value 0.464 nT and σ = 0.009 nT. Since the uncertainty σ corresponds to the instrument and digitization noise, these observations provided an upper limit to the turbulence in the ISMF. The distributions of the hourly increments of B were Gaussian distributions with σ = 0.05 nT, 0.°4, and 0.°4, respectively, indicating that the V1 did not detect evidence of ''intermittent bursts'' of interstellar turbulence.

  14. Pollution Probe.

    Science.gov (United States)

    Chant, Donald A.

    This book is written as a statement of concern about pollution by members of Pollution Probe, a citizens' anti-pollution group in Canada. Its purpose is to create public awareness and pressure for the eventual solution to pollution problems. The need for effective government policies to control the population explosion, conserve natural resources,…

  15. Space, time, matter

    CERN Document Server

    Weyl, Hermann

    1999-01-01

    Excellent introduction probes deeply into Euclidean space, Riemann's space, Einstein's general relativity, gravitational waves and energy, and laws of conservation. "A classic of physics." - British Journal for Philosophy and Science.

  16. The representations of the overseas world in the De Bry collection of voyages (1590-1634)

    NARCIS (Netherlands)

    van Groesen, M.

    2008-01-01

    This book deals with the De Bry collection of voyages, one of the most monumental publications of Early Modern Europe. It analyzes the textual and iconographic changes the De Bry publishing family made to travel accounts describing Asia, Africa and the New World. It discusses this editorial strategy

  17. 33 CFR 157.228 - Isolating Valves: Closed during a voyage.

    Science.gov (United States)

    2010-07-01

    ... SECURITY (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Dedicated Clean Ballast Tanks Operations § 157.228 Isolating Valves: Closed during a voyage. (a) The master of each U.S. tank vessel under §...

  18. The Voyage of the Beagle: Field Work Lessons from Charles Darwin.

    Science.gov (United States)

    Smith, Louis M.

    1987-01-01

    Analyzes Charles Darwin's letters to his family during his voyage on H.M.S. Beagle. Relates the information to the development of Darwin's professional identity and the degree to which the concepts, field methods, and research methods revealed in Darwin's personal correspondence are useful to students of educational administration. (MD)

  19. Voyager observations of the interaction of the heliosphere with the interstellar medium.

    Science.gov (United States)

    Richardson, John D

    2013-05-01

    This paper provides a brief review and update on the Voyager observations of the interaction of the heliosphere with the interstellar medium. Voyager has found many surprises: (1) a new energetic particle component which is accelerated at the termination shock (TS) and leaks into the outer heliosphere forming a foreshock region; (2) a termination shock which is modulated by energetic particles and which transfers most of the solar wind flow energy to the pickup ions (not the thermal ions); (3) the heliosphere is asymmetric; (4) the TS does not accelerate anomalous cosmic rays at the Voyager locations; and (5) the plasma flow in the Voyagers 1 (V1) and 2 (V2) directions are very different. At V1 the flow was small after the TS and has recently slowed to near zero, whereas at V2 the speed has remained constant while the flow direction has turned tailward. V1 may have entered an extended boundary region in front of the heliopause (HP) in 2010 in which the plasma flow speeds are near zero.

  20. Voyager observations of the interaction of the heliosphere with the interstellar medium

    Directory of Open Access Journals (Sweden)

    John D. Richardson

    2013-05-01

    Full Text Available This paper provides a brief review and update on the Voyager observations of the interaction of the heliosphere with the interstellar medium. Voyager has found many surprises: (1 a new energetic particle component which is accelerated at the termination shock (TS and leaks into the outer heliosphere forming a foreshock region; (2 a termination shock which is modulated by energetic particles and which transfers most of the solar wind flow energy to the pickup ions (not the thermal ions; (3 the heliosphere is asymmetric; (4 the TS does not accelerate anomalous cosmic rays at the Voyager locations; and (5 the plasma flow in the Voyagers 1 (V1 and 2 (V2 directions are very different. At V1 the flow was small after the TS and has recently slowed to near zero, whereas at V2 the speed has remained constant while the flow direction has turned tailward. V1 may have entered an extended boundary region in front of the heliopause (HP in 2010 in which the plasma flow speeds are near zero.

  1. The Voyage of the Beagle: Field Work Lessons from Charles Darwin.

    Science.gov (United States)

    Smith, Louis M.

    1987-01-01

    Analyzes Charles Darwin's letters to his family during his voyage on H.M.S. Beagle. Relates the information to the development of Darwin's professional identity and the degree to which the concepts, field methods, and research methods revealed in Darwin's personal correspondence are useful to students of educational administration. (MD)

  2. Preservation Methods Utilized for Space Food

    Science.gov (United States)

    Vodovotz, Yael; Bourland, Charles

    2000-01-01

    Food for manned space flight has been provided by NASA-Johnson Space Center since 1962. The various mission scenarios and space craft designs dictated the type of food preservation methodologies required to meet mission objectives. The preservation techniques used in space flight include freeze-dehydration, thermostabilization, irradiation, freezing and moisture adjustment. Innovative packaging material and techniques enhanced the shelf-stability of the food items. Future space voyages may include extended duration exploration missions requiring new packaging materials and advanced preservation techniques to meet mission goals of up to 5-year shelf-life foods.

  3. Magnetic Reconnection in the Heliospheric Current Sheet: The Implications of the Different Environments Seen by the VoyagerSpacecraft

    Science.gov (United States)

    Swisdak, M. M.; Drake, J. F.; Opher, M.

    2014-12-01

    The magnetic field abutting the heliospheric current sheet (HCS) is primarily in the azimuthal direction, either east-to-west or west-to-east. Mis-alignment of the solar rotational and magnetic axesleads to the characteristic ballerina-skirt shape of the HCS and during the solar cycle there can be large excursions in the sheet's latitudinal extent. Voyager 2's observations of energetic electrondropouts are related to its crossing of this boundary. Magnetic reconnection is also thought to occur as the HCS compresses and narrows between the termination shock and the heliopause. Near theequator the two HCS field alignments are present in roughly equal amounts, while near the edges the distribution can be considerably skewed. This will lead to substantial differences in the environmentsof the two Voyager spacecraft since Voyager 1 is north of the equator, but firmly in the sector region, while Voyager 2 is south of the equator and skirting the edges of the sector region. We presentparticle-in-cell simulations demonstrating the consequences of the reconnection of asymmetric amounts of flux. In particular, we will discuss Voyager 2's remaining time in the heliosphere -- including theimplications for the solar wind velocity, energetic particle transport, and the expected structure of Voyager 2's heliopause crossing -- and compare it with the data collected from Voyager 1.

  4. Emission-Line Galaxies from the Hubble Space Telescope Probing Evolution and Reionization Spectroscopically (PEARS) Grism Survey. II: The Complete Sample

    CERN Document Server

    Pirzkal, Nor; Ly, Chun; Malhotra, Sangeeta; Rhoads, James E; Grogin, Norman A; Dahlen, Tomas; Meurer, Gerhardt R; Walsh, Jeremy R; Hathi, Nimish P; Cohen, Seth H; Bellini, Andrea; Holwerda, Benne W; Straughn, Amber N; Mechtley, Matthew

    2012-01-01

    We present a full analysis of the Probing Evolution And Reionization Spectroscopically (PEARS) slitess grism spectroscopic data obtained with the Advanced Camera for Surveys on HST. PEARS covers fields within both the Great Observatories Origins Deep Survey (GOODS) North and South fields, making it ideal as a random survey of galaxies, as well as the availability of a wide variety of ancillary observations to support the spectroscopic results. Using the PEARS data we are able to identify star forming galaxies within the redshift volume 0 1e9} M_sun decreases by an order of magnitude at z<0.5 relative to the number at 0.5

  5. Testing universality of cosmic-ray acceleration with proton/helium data from AMS and Voyager-1

    Science.gov (United States)

    Tomassetti, Nicola

    2017-08-01

    The Alpha Magnetic Spectrometer (AMS) experiment onboard the International Space Station (ISS) has recently measured the proton and helium spectra in cosmic rays (CRs) in the GeV-TeV energy region. The spectra of proton and helium are found to progressively harden at rigidity R = pc / Ze ≳ 200 GV, while the proton-to-helium ratio as function of rigidity is found to fall off steadily as p/He ∝R-0.08 . The decrease of the p/He ratio is often interpreted in terms of particle-dependent acceleration, which is in contrast with the universal nature of diffusive-shock-acceleration mechanisms. A different explanation is that the p-He anomaly originates from a flux transition between two components: a sub-TeV flux component (L) provided by hydrogen-rich supernova remnants with soft acceleration spectra, and a multi-TeV component (G) injected by younger sources with amplified magnetic fields and hard spectra. In this scenario the universality of particle acceleration is not violated because both source components provide composition-blind injection spectra. The present work is aimed at testing the universality of CR acceleration using the low-energy part of the CR flux, which is expected to be dominated by the L-type component. However, at kinetic energy of ∼0.5-10 GeV, the CR fluxes are significantly affected by energy losses and solar modulation, hence a proper modeling of Galactic and heliospheric propagation is required. To set the key properties of the L-source component, I have used the Voyager-1 data collected in the interstellar space. To compare my calculations with the AMS data, I have performed a determination of the force-field modulation parameter using neutron monitor measurements. I will show that the recent p-He data reported by AMS and Voyager-1 are in good agreement with the predictions of such a scenario, supporting the hypothesis that CRs are released in the Galaxy by universal, composition-blind accelerators. At energies below ∼0.5 GeV/n, however

  6. Exo-C: a Probe-Scale Space Mission to Directly Image and Spectroscopically Characterize Exoplanetary Systems Using an Internal Coronagraph

    Science.gov (United States)

    Stapelfeldt, Karl R.; Brenner, Michael P.; Warfield, Keith R.; Dekens, Frank G.; Belikov, Ruslan; Brugarolas, Paul B.; Bryden, Geoffrey; Cahoy, Kerri L.; Chakrabarti, Supriya; Dubovitsky, Serge; hide

    2014-01-01

    "Exo-C" is NASA's first community study of a modest aperture space telescope designed for high contrast observations of exoplanetary systems. The mission will be capable of taking optical spectra of nearby exoplanets in reflected light, discover previously undetected planets, and imaging structure in a large sample of circumstellar disks. It will obtain unique science results on planets down to super-Earth sizes and serve as a technology pathfinder toward an eventual flagship-class mission to find and characterize habitable exoplanets. We present the mission/payload design and highlight steps to reduce mission cost/risk relative to previous mission concepts. At the study conclusion in 2015, NASA will evaluate it for potential development at the end of this decade. Keywords: Exoplanets, high contrast imaging, optical astronomy, space mission concepts

  7. Practice and Probing on Urban Road Green Space Landscape Planning of CBD%城市CBD道路绿地景观规划实践与探索

    Institute of Scientific and Technical Information of China (English)

    徐英

    2011-01-01

    Landscape planning and design of the road green space in a city plays an important role in urban construction and development.The standard of road green space is even more higher in central business district (CBD) for its special urban landscape features.It includes not only the construction of the overall image of road landscape, but also a unique cultural atmosphere of CBD.Taking Lin-gang CBD in Jiangyin as example, planning theory, the overall layout and characteristic positioning in road green space design were discussed.%城市中央商务区(CBD)特殊的环境景观特征对道路绿地景观营造提出了更高的要求,既包括道路景观整体形象的建构,也包括CBD特有文化氛围的创造.以江阴市临港新城中央商务区道路绿地景观规划为例,探讨其在理念、总体布局和特色定位等方面的规划控制.

  8. The theory of Langmuir probes in strong electrostatic potential structures

    Science.gov (United States)

    Borovsky, J. E.

    1986-01-01

    The operation of collecting and emitting Langmuir probes and double probes within time-stationary strong electrostatic potential structures is analyzed. The cross sections of spherical and cylindrical probes to charged particles within the structures are presented and used to obtain the current-voltage characteristics of idealized probes. The acquisition of plasma parameters from these characteristics is outlined, and the operation of idealized floating double-probe systems is analyzed. Probe surface effects are added to the idealized theory, and some surface effects pertinent to spacecraft probes are quantified. Magnetic field effects on idealized probes are examined, and the time required for floating probes to change their potentials by collecting charge and by emitting photoelectrons is discussed. Calculations on the space-charge effects of probe-perturbed beams and on the space-charge limiting of electron emission are given in an appendix.

  9. 在ILC上用γγ→Z过程检验非对易时空标度%Probing Noncommutative Space-Time Scale Using γγ Z at ILC

    Institute of Scientific and Technical Information of China (English)

    何小刚; 李学潜

    2007-01-01

    In this talk we report our work on testing Noncommutative Space-Time Scale Using γγ → Z at ILC. In ordinary space-time theory, decay of a spin-1 particle into two photons is strictly forbidden due to the Yang's Theorem. With noncommutative space-time this process can occur. This process thus provides an important probe for noncommutative space-time. The γγ collision mode at the ILC provides an ideal place to carry out such a study. Assuming an integrated luminosity of 500fb-1, we show that the constraint which can be achieved on Г(Z→ γγ) is three to four orders of magnitude better than the current bound of 5.2 × 10-5 GeV.The noncommutative scale can be probed up to a few TeVs.%讨论关于在ILC用gamma gamma到Z过程检验非对易时空能标(原文发在hep-ph/0604115).在通常时空量子场论中,由杨氏定理可知一个自旋为1的粒子不可能衰变为两个光子.但在非对易时空中此过程是允许的.因此这个过程能作为检验非对易时空的工具.ILC的光子对撞模式能实现这个过程.如果总亮度能达到500fb-1,我们证明对Gamma(Z to gamma gamma)宽度的测量精度将比现有限制(<5.2×10-5GeV)好3-4个数量级.对非对易时空能标的检测可高达几个TeV.

  10. Space space space

    CERN Document Server

    Trembach, Vera

    2014-01-01

    Space is an introduction to the mysteries of the Universe. Included are Task Cards for independent learning, Journal Word Cards for creative writing, and Hands-On Activities for reinforcing skills in Math and Language Arts. Space is a perfect introduction to further research of the Solar System.

  11. A Fast-Response Atmospheric Turbulence (FRAT) Probe with Gas-Sampling Ducts Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposal is to design, construct and test a high-frequency-response air-data probe, the Fast Response Atmospheric Turbulence probe (FRAT probe)...

  12. Search for the exit: Voyager 1 at heliosphere's border with the galaxy.

    Science.gov (United States)

    Krimigis, S M; Decker, R B; Roelof, E C; Hill, M E; Armstrong, T P; Gloeckler, G; Hamilton, D C; Lanzerotti, L J

    2013-07-12

    We report measurements of energetic (>40 kiloelectron volts) charged particles on Voyager 1 from the interface region between the heliosheath, dominated by heated solar plasma, and the local interstellar medium, which is expected to contain cold nonsolar plasma and the galactic magnetic field. Particles of solar origin at Voyager 1, located at 18.5 billion kilometers (123 astronomical units) from the Sun, decreased by a factor of >10(3) on 25 August 2012, while those of galactic origin (cosmic rays) increased by 9.3% at the same time. Intensity changes appeared first for particles moving in the azimuthal direction and were followed by those moving in the radial and antiradial directions with respect to the solar radius vector. This unexpected heliospheric "depletion region" may form part of the interface between solar plasma and the galaxy.

  13. Surface ozone observations during voyages to the Arctic and Antarctic regions

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Surface ozone concentration and UV-B data between 75°N and 70°S were obtained aboard the Chinese polar scientific vessel "Xue-long" (Snow-Dragon) during the first voyage to the Arctic and the 16th to the Antarctic in 1999-2000. Analysis of these data presents that variations of the surface ozone concentration have small amplitude during voyages except the mid-latitude in the Northern Hemisphere. As a whole, average surface ozone concentration in the Northern Hemisphere is higher than that in the Southern, and high value occurred when the ship sailed close to the continents. The average diurnal variations of the surface ozone in the Northern Hemisphere are also higher compared to the southern counterparts, and high diurnal variations were found at low latitudes, and relative low level in the polar region.

  14. Voyager 2 observations of plasmas and flows out to 104 AU

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, J. D. [Kavli Center for Astrophysics and Space Science, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Decker, R. B., E-mail: jdr@space.mit.edu, E-mail: robert.decker@apljhu.edu [Applied Physics Laboratory, Johns Hopkins University, Laurel, MD (United States)

    2014-09-10

    Voyager 2 has crossed through 20 AU of the heliosheath; assuming the same heliosheath thickness as at Voyager 1, it is now two-thirds of the way to the heliopause. The plasma data are generally of good quality, although the increasing flow angle of the plasma makes analysis more difficult. The average plasma speed has remained constant but the flow angles have increased to almost 60° in the RT plane and to almost 30° in the RN plane. The average density and thermal speed have been constant since a density increase observed in 2011. Comparison of V2 plasma flows derived from plasma science experiment (PLS) data and Low Energy Charged Particle (LECP) proton anisotropies give good agreement except when heavy ion contributions or non-convective proton anisotropies are observed in the LECP data.

  15. Achievement of 2011 European low-density lipoprotein cholesterol (LDL-C) goals of either VOYAGER.

    Science.gov (United States)

    Karlson, Björn W; Nicholls, Stephen J; Lundman, Pia; Palmer, Mike K; Barter, Philip J

    2013-05-01

    Guidelines published in 2011 by the European Atherosclerosis Society and the European Society of Cardiology recommend a goal of either low-density lipoprotein cholesterol (LDL-C) VOYAGER individual patient data meta-analysis treated with rosuvastatin 10-40 mg, atorvastatin 10-80 mg or simvastatin 10-80 mg who achieved this goal. We analysed 25,075 patient exposures from high-risk patients. Paired comparisons were made between each rosuvastatin dose and an equal or higher dose of either atorvastatin or simvastatin, with a series of meta-analyses that included only randomised studies that directly compared rosuvastatin and its comparator treatments. As statin dose increased, higher percentages of patients achieved LDL-C VOYAGER highlight the importance of an effective statin at an appropriate dose to achieve treatment goals for LDL-C in patients with very high cardiovascular risk. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  16. Récits de voyage, fiction et voyageurs fictifs dans American Notes de Charles Dickens

    Directory of Open Access Journals (Sweden)

    Nathalie VANFASSE

    2005-06-01

    Full Text Available Dickens effectua sa première visite aux Etats-Unis de janvier à juin 1842. Ce séjour inclut un mois au Canada. À la suite de ce voyage, le romancier publia American Notes qui parurent la même année. Dans son ouvrage intitulé Innocent Abroad : Charles Dickens’s American Engagements (1990, Jerome Meckier énumère les récits de voyage consacrés aux Etats-Unis que Dickens est supposé avoir consultés ou lus avant son propre périple : Diary in America (1839 du Capitaine Frederick Marryat, Observat...

  17. Genet's Fantastic Voyage in Miracle de la Rose: All at Sea about Maternity

    Directory of Open Access Journals (Sweden)

    Elizabeth Richardson Viti

    1990-06-01

    Full Text Available Together psychoanalytical and feminist criticism appear to uncover the very composition of Jean Genet's inversion. Indeed, in this regard the Miracle de la Rose dream sequence which focuses on an extraordinary voyage through the body of Harcamone, the very imprimatur of bisexuality defined in Cixous' Le rire de la méduse , holds singular importance. Abandoned by his biological mother, Genet sees himself as a "produit synthétique" who has to belong to someone in order to be. Genet simply does not exist unless he can establish, not the Lacanian Name-of-the-Father, but rather the Name-of-the- Mother . The dream reveals a Freudian resolution of ambivalence when its author "kills" the Mother by becoming her through a mediation of Subject and Other which parallels Irigaray's interpenetration of mother and child. Mediation becomes transformation as Genet's fantastic voyage allows him to say, "je nais."

  18. Spontaneous Symmetry Probing

    CERN Document Server

    Nicolis, Alberto

    2011-01-01

    For relativistic quantum field theories, we consider Lorentz breaking, spatially homogeneous field configurations or states that evolve in time along a symmetry direction. We dub this situation "spontaneous symmetry probing" (SSP). We mainly focus on internal symmetries, i.e. on symmetries that commute with the Poincare group. We prove that the fluctuations around SSP states have a Lagrangian that is explicitly time independent, and we provide the field space parameterization that makes this manifest. We show that there is always a gapless Goldstone excitation that perturbs the system in the direction of motion in field space. Perhaps more interestingly, we show that if such a direction is part of a non-Abelian group of symmetries, the Goldstone bosons associated with spontaneously broken generators that do not commute with the SSP one acquire a gap, proportional to the SSP state's "speed". We outline possible applications of this formalism to inflationary cosmology.

  19. WHY ARE THE MAGNETIC FIELD DIRECTIONS MEASURED BY VOYAGER 1 ON BOTH SIDES OF THE HELIOPAUSE SO SIMILAR?

    Energy Technology Data Exchange (ETDEWEB)

    Grygorczuk, J.; Czechowski, A.; Grzedzielski, S., E-mail: jolagry@cbk.waw.pl [Space Research Centre, Warsaw (Poland)

    2014-07-10

    The solar wind carves a cavity in the interstellar plasma bounded by a surface, called the heliopause (HP), that separates the plasma and magnetic field of solar origin from those of interstellar origin. It is now generally accepted that in 2012 August Voyager 1 (V1) crossed that boundary. Unexpectedly, the magnetic fields on both sides of the HP, although theoretically independent of each other, were found to be similar in direction. This delayed the identification of the boundary as the HP and led to many alternative explanations. Here, we show that the Voyager 1 observations can be readily explained and, after the Interstellar Boundary Explorer (IBEX) discovery of the ribbon, could even have been predicted. Our explanation relies on the fact that the Voyager 1 and undisturbed interstellar field directions (which we assume to be given by the IBEX ribbon center (RC)) share the same heliolatitude (∼34.°5) and are not far separated in longitude (difference ∼27°). Our result confirms that Voyager 1 has indeed crossed the HP and offers the first independent confirmation that the IBEX RC is in fact the direction of the undisturbed interstellar magnetic field. For Voyager 2, we predict that the difference between the inner and outer magnetic field directions at the HP will be significantly larger than that observed by Voyager 1 (∼30° instead of ∼20°), and that the outer field direction will be close to the RC.

  20. Quantitative measurements of Jupiter, Saturn, their rings and satellites made from Voyager imaging data

    Science.gov (United States)

    Collins, S. A.; Bunker, A. S.

    1983-01-01

    The Voyager spacecraft cameras use selenium-sulfur slow scan vidicons to convert focused optical images into sensible electrical signals. The vidicon-generated data thus obtained are the basis of measurements of much greater precision than was previously possible, in virtue of their superior linearity, geometric fidelity, and the use of in-flight calibration. Attention is given to positional, radiometric, and dynamical measurements conducted on the basis of vidicon data for the Saturn rings, the Saturn satellites, and the Jupiter atmosphere.

  1. C-smithing of Voyager 2 non-imaging instrument pointing information at Uranus

    Science.gov (United States)

    Wang, Tseng-Chan; Acton, Charles H.; Underwood, Ian M.; Synnott, Stephen P.

    1988-01-01

    The development of a family of techniques, collectively called C-smithing, for improving spacecraft nonimaging instrument pointing knowledge is discussed. C-smithing studies using data from the Voyager 2 Uranus Encounter show that significant improvements in pointing knowledge for nonimaging instruments can be achieved with these techniques. This improved pointing information can be used to regenerate instrument viewing geometry parameters for the encounter, which can then be made available to science investigators.

  2. Pneumatic Proboscis Heat Flow Probe Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The heat flow probe directly answers requirements in the topic: S1.11 Lunar Science Instruments and Technology: "Geophysical Measurements: Systems, subsystems, and...

  3. Sapphire Viewports for a Venus Probe Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed Phase 1 program will demonstrate that sapphire viewports are feasible for use in Venus probes. TvU's commercial viewport products have demonstrated that...

  4. Origins, Loss, and Recovery in Patrick Modiano's Voyage de noces and Dora Bruder

    Directory of Open Access Journals (Sweden)

    Ann L. Murphy

    2005-06-01

    Full Text Available By alluding to the writing of his 1990 novel Voyage de noces in the course of the narration of 1997 Dora Bruder , author Patrick Modiano invites an examination of the connections between these two works. This paper demonstrates how Voyage de noces and Dora Bruder , when studied together as a sort of diptych, are informed by what commentators have described as Modiano's simultaneous preoccupations with the expression of absence and loss, on the one hand, and with the use of writing to compensate for these, on the other. Specifically, a formal and thematic relationship between these two texts is shaped first by a movement from origins to loss, as developed in Voyage de noces , and then by an inverse movement from loss to recovery as outlined in Dora Bruder . However, just as the fullness of being that typically characterizes the idealized version of origins—here, meaningful parental presence and a sense of personal identity—is always already deflated by the recognition that this fullness is not a given but rather remains to be realized, absolute recovery, too, is impossible.

  5. Jules Verne Voyager, Jr: An Interactive Map Tool for Teaching Plate Tectonics

    Science.gov (United States)

    Hamburger, M. W.; Meertens, C. M.

    2010-12-01

    We present an interactive, web-based map utility that can make new geological and geophysical results accessible to a large number and variety of users. The tool provides a user-friendly interface that allows users to access a variety of maps, satellite images, and geophysical data at a range of spatial scales. The map tool, dubbed 'Jules Verne Voyager, Jr.', allows users to interactively create maps of a variety of study areas around the world. The utility was developed in collaboration with the UNAVCO Consortium for study of global-scale tectonic processes. Users can choose from a variety of base maps (including "Face of the Earth" and "Earth at Night" satellite imagery mosaics, global topography, geoid, sea-floor age, strain rate and seismic hazard maps, and others), add a number of geographic and geophysical overlays (coastlines, political boundaries, rivers and lakes, earthquake and volcano locations, stress axes, etc.), and then superimpose both observed and model velocity vectors representing a compilation of 2933 GPS geodetic measurements from around the world. A remarkable characteristic of the geodetic compilation is that users can select from some 21 plates' frames of reference, allowing a visual representation of both 'absolute' plate motion (in a no-net rotation reference frame) and relative motion along all of the world's plate boundaries. The tool allows users to zoom among at least three map scales. The map tool can be viewed at http://jules.unavco.org/VoyagerJr/Earth. A more detailed version of the map utility, developed in conjunction with the EarthScope initiative, focuses on North America geodynamics, and provides more detailed geophysical and geographic information for the United States, Canada, and Mexico. The ‘EarthScope Voyager’ can be accessed at http://jules.unavco.org/VoyagerJr/EarthScope. Because the system uses pre-constructed gif images and overlays, the system can rapidly create and display maps to a large number of users

  6. Scanning microscopic four-point conductivity probes

    DEFF Research Database (Denmark)

    Petersen, Christian Leth; Hansen, Torben Mikael; Bøggild, Peter

    2002-01-01

    A method for fabricating microscopic four-point probes is presented. The method uses silicon-based microfabrication technology involving only two patterning steps. The last step in the fabrication process is an unmasked deposition of the conducting probe material, and it is thus possible to select...... the conducting material either for a silicon wafer or a single probe unit. Using shadow masking photolithography an electrode spacing (pitch) down to 1.1 mum was obtained, with cantilever separation down to 200 run. Characterisation measurements have shown the microscopic probes to be mechanically very flexible...

  7. The Colonization of Space. An Anthropological Outlook

    Directory of Open Access Journals (Sweden)

    Moreno Tiziani

    2013-06-01

    Full Text Available The colonization of space implies an adaptation of both physical and cultural type. The human species is characterized by a great adaptive capacity that, in a basically extreme environment, reveals all its plasticity. However, this capacity must be aided by appropriate technological solutions that identify the problems related to long stays in space, and to long space voyages. Anthropology could aid future colonizers rethinking the environment of the spacecrafts, and the habitats of future colonies. Last but not least, anthropology can prepare them to a possible encounter with alien intelligences very different from human way of thinking.

  8. Proximal Probes Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Proximal Probes Facility consists of laboratories for microscopy, spectroscopy, and probing of nanostructured materials and their functional properties. At the...

  9. PROcess Based Diagnostics PROBE

    Science.gov (United States)

    Clune, T.; Schmidt, G.; Kuo, K.; Bauer, M.; Oloso, H.

    2013-01-01

    Many of the aspects of the climate system that are of the greatest interest (e.g., the sensitivity of the system to external forcings) are emergent properties that arise via the complex interplay between disparate processes. This is also true for climate models most diagnostics are not a function of an isolated portion of source code, but rather are affected by multiple components and procedures. Thus any model-observation mismatch is hard to attribute to any specific piece of code or imperfection in a specific model assumption. An alternative approach is to identify diagnostics that are more closely tied to specific processes -- implying that if a mismatch is found, it should be much easier to identify and address specific algorithmic choices that will improve the simulation. However, this approach requires looking at model output and observational data in a more sophisticated way than the more traditional production of monthly or annual mean quantities. The data must instead be filtered in time and space for examples of the specific process being targeted.We are developing a data analysis environment called PROcess-Based Explorer (PROBE) that seeks to enable efficient and systematic computation of process-based diagnostics on very large sets of data. In this environment, investigators can define arbitrarily complex filters and then seamlessly perform computations in parallel on the filtered output from their model. The same analysis can be performed on additional related data sets (e.g., reanalyses) thereby enabling routine comparisons between model and observational data. PROBE also incorporates workflow technology to automatically update computed diagnostics for subsequent executions of a model. In this presentation, we will discuss the design and current status of PROBE as well as share results from some preliminary use cases.

  10. Factors influencing the en route survivorship and post-voyage growth of a common ship biofouling organism, Bugula neritina.

    Science.gov (United States)

    Schimanski, Kate B; Piola, Richard F; Goldstien, Sharyn J; Floerl, Oliver; Grandison, Clare; Atalah, Javier; Hopkins, Grant A

    2016-09-01

    The likelihood that viable non-indigenous biofouling species will survive a voyage on a vessel is influenced by a range of factors, including the speed, duration, and route of the voyage and the amount of time the vessel spends in port. In this study, a land-based dynamic flow device was used to test the effect of recruit age, vessel speed and voyage duration on the survivorship and growth of the bryozoan Bugula neritina. In the experiment, one-week-old recruits had a higher likelihood (100%) of surviving voyages than older (one-month-old, 90%) or younger (one-day-old, 79%) recruits, but survival was not influenced by vessel speed (6 and 18 knots) or voyage duration (two and eight days). The results suggest that the non-indigenous species B. neritina can be effectively transferred at a range of ages but one-week-old recruits are more likely to survive the translocation process and survive in the recipient environment.

  11. Louise Colet (1810-1876, Promenade en Hollande (1859 : voyage et histoire

    Directory of Open Access Journals (Sweden)

    Madeleine van Strien-Chardonneau

    2012-06-01

    Full Text Available Louise Colet, poétesse, romancière et journaliste a écrit également plusieurs récits de voyage. Cet article se propose d’étudier le premier d’entre eux, Promenade en Hollande (1859, en le replaçant dans le contexte de l’évolution du genre du voyage et la longue tradition des récits de voyageurs français en Hollande puis en explorant la façon dont la voyageuse insère dans sa relation de voyage une réflexion sur l’histoire et le temps. En jouant sur diverses temporalités, Louise Colet produit un récit hybride, entre récit « traditionnel » et reportage, et affirme ainsi son identité d’écrivaine.  Louise Colet, poet, novelist and journalist, is also the author of several travelogues. In this article we study the first, Promenade en Hollande (1859. We begin by situating it in the context of the evolution of the genre, particularly that of the long tradition of French travellers relating their journeys in Holland. Then we look at the way in which she widens the scope of her travelogue by introducing comments on history. Mixing the past with the present, Louise Colet produces a hybrid account, something in between the traditional travelogue and a journalist’s report, and in doing so she affirms her identity as an author.  

  12. Radiation Transport of Heliospheric Lyman-alpha from Combined Cassini and Voyager Data Sets

    Science.gov (United States)

    Pryor, W.; Gangopadhyay, P.; Sandel, B.; Forrester, T.; Quemerais, E.; Moebius, E.; Esposito, L.; Stewart, I.; McClintock, W.; Jouchoux, A.; hide

    2008-01-01

    Heliospheric neutral hydrogen scatters solar Lyman-alpha radiation from the Sun with '27-day' intensity modulations observed near Earth due to the Sun's rotation combined with Earth's orbital motion. These modulations are increasingly damped in amplitude at larger distances from the Sun due to multiple scattering in the heliosphere, providing a diagnostic of the interplanetary neutral hydrogen density independent of instrument calibration. This paper presents Cassini data from 2003-2004 obtained downwind near Saturn at approximately 10 AU that at times show undamped '27-day' waves in good agreement with the single-scattering models of Pryor et al., 1992. Simultaneous Voyager 1 data from 2003- 2004 obtained upwind at a distance of 88.8-92.6 AU from the Sun show waves damped by a factor of -0.21. The observed degree of damping is interpreted in terms of Monte Carlo multiple-scattering calculations (e.g., Keller et al., 1981) applied to two heliospheric hydrogen two-shock density distributions (discussed in Gangopadhyay et al., 2006) calculated in the frame of the Baranov-Malama model of the solar wind interaction with the two-component (neutral hydrogen and plasma) interstellar wind (Baranov and Malama 1993, Izmodenov et al., 2001, Baranov and Izmodenov, 2006). We conclude that multiple scattering is definitely occurring in the outer heliosphere. Both models compare favorably to the data, using heliospheric neutral H densities at the termination shock of 0.085 cm(exp -3) and 0.095 cm(exp -3). This work generally agrees with earlier discussions of Voyager data in Quemerais et al., 1996 showing the importance of multiple scattering but is based on Voyager data obtained at larger distances from the Sun (with larger damping) simultaneously with Cassini data obtained closer to the Sun.

  13. Estimation of a genetically viable population for multigenerational interstellar voyaging: Review and data for project Hyperion

    Science.gov (United States)

    Smith, Cameron M.

    2014-04-01

    Designing interstellar starships for human migration to exoplanets requires establishing the starship population, which factors into many variables including closed-ecosystem design, architecture, mass and propulsion. I review the central issues of population genetics (effects of mutation, migration, selection and drift) for human populations on such voyages, specifically referencing a roughly 5-generation (c. 150-year) voyage currently in the realm of thought among Icarus Interstellar's Project Hyperion research group. I present several formulae as well as concrete numbers that can be used to help determine populations that could survive such journeys in good health. I find that previously proposed such populations, on the order of a few hundred individuals, are significantly too low to consider based on current understanding of vertebrate (including human) genetics and population dynamics. Population genetics theory, calculations and computer modeling determine that a properly screened and age- and sex-structured total founding population (Nc) of anywhere from roughly 14,000 to 44,000 people would be sufficient to survive such journeys in good health. A safe and well-considered Nc figure is 40,000, an Interstellar Migrant Population (IMP) composed of an Effective Population [Ne] of 23,400 reproductive males and females, the rest being pre- or post-reproductive individuals. This number would maintain good health over five generations despite (a) increased inbreeding resulting from a relatively small human population, (b) depressed genetic diversity due to the founder effect, (c) demographic change through time and (d) expectation of at least one severe population catastrophe over the 5-generation voyage.

  14. Probe tip heating assembly

    Science.gov (United States)

    Schmitz, Roger William; Oh, Yunje

    2016-10-25

    A heating assembly configured for use in mechanical testing at a scale of microns or less. The heating assembly includes a probe tip assembly configured for coupling with a transducer of the mechanical testing system. The probe tip assembly includes a probe tip heater system having a heating element, a probe tip coupled with the probe tip heater system, and a heater socket assembly. The heater socket assembly, in one example, includes a yoke and a heater interface that form a socket within the heater socket assembly. The probe tip heater system, coupled with the probe tip, is slidably received and clamped within the socket.

  15. Saturn's rings through a microscope - Particle size constraints from the Voyager PPS scan

    Science.gov (United States)

    Showalter, Mark R.; Nicholson, Philip D.

    1990-01-01

    The Voyager-2 photopolarimeter PPS experiment obtained the highest resolution of any ring observation of Saturn, profiling the variation of optical depth in radial steps of about 100 meters. A detailed treatment of the PPS statistics is presented here, and it is shown how these statistics can be related to the particle size distribution. An expression for the excess noise in the scan due to large particles is obtained, and the observed noise is used to constrain the upper end of the size distribution through the rings. It is shown that the Cassini Division and the C Ring have the smallest proportion of large particles, while the A ring has the largest proportion.

  16. Phenomenology of Neptune's radio emissions observed by the Voyager planetary radio astronomy experiment

    Science.gov (United States)

    Pedersen, B. M.; Lecacheux, A.; Zarka, P.; Aubier, M. G.; Kaiser, M. L.; Desch, M. D.

    1992-01-01

    The Neptune flyby in 1989 added a new planet to the known number of magnetized planets generating nonthermal radio emissions. We review the Neptunian radio emission morphology as observed by the planetary radio astronomy experiment on board Voyager 2 during a few weeks before and after closest approach. We present the characteristics of the two observed recurrent main components of the Neptunian kilometric radiation, i.e., the 'smooth' and the 'bursty' emissions, and we describe the many specific features of the radio spectrum during closest approach.

  17. Reusable science tools for analog exploration missions: xGDS Web Tools, VERVE, and Gigapan Voyage

    Science.gov (United States)

    Lee, Susan Y.; Lees, David; Cohen, Tamar; Allan, Mark; Deans, Matthew; Morse, Theodore; Park, Eric; Smith, Trey

    2013-10-01

    The Exploration Ground Data Systems (xGDS) project led by the Intelligent Robotics Group (IRG) at NASA Ames Research Center creates software tools to support multiple NASA-led planetary analog field experiments. The two primary tools that fall under the xGDS umbrella are the xGDS Web Tools (xGDS-WT) and Visual Environment for Remote Virtual Exploration (VERVE). IRG has also developed a hardware and software system that is closely integrated with our xGDS tools and is used in multiple field experiments called Gigapan Voyage. xGDS-WT, VERVE, and Gigapan Voyage are examples of IRG projects that improve the ratio of science return versus development effort by creating generic and reusable tools that leverage existing technologies in both hardware and software. xGDS Web Tools provides software for gathering and organizing mission data for science and engineering operations, including tools for planning traverses, monitoring autonomous or piloted vehicles, visualization, documentation, analysis, and search. VERVE provides high performance three dimensional (3D) user interfaces used by scientists, robot operators, and mission planners to visualize robot data in real time. Gigapan Voyage is a gigapixel image capturing and processing tool that improves situational awareness and scientific exploration in human and robotic analog missions. All of these technologies emphasize software reuse and leverage open source and/or commercial-off-the-shelf tools to greatly improve the utility and reduce the development and operational cost of future similar technologies. Over the past several years these technologies have been used in many NASA-led robotic field campaigns including the Desert Research and Technology Studies (DRATS), the Pavilion Lake Research Project (PLRP), the K10 Robotic Follow-Up tests, and most recently we have become involved in the NASA Extreme Environment Mission Operations (NEEMO) field experiments. A major objective of these joint robot and crew experiments is

  18. LHC 2008 talks Peut-on voyager dans le temps? (Is time travel possible?)

    CERN Multimedia

    2008-01-01

    Scientific magazines (and sometimes even scientists themselves) regularly talk about the possibility of travelling through time. It has also been the subject of many science-fiction novels. We will first discuss what we mean when we talk about time travel, then explain what contemporary physics has to say about it. Thursday, 12 June 2008 at 8.00 p.m. Peut-on voyager dans le temps ? Etienne Klein Physicist at CEA and Doctor of Philosophy of Science The Globe, first floor No specialist knowledge required. Entrance free. http://www.cern.ch/globe

  19. INTERPRETATION OF THE DISTURBANCE IN GALACTIC COSMIC RAYS OBSERVED ON VOYAGER 1 BEYOND THE HELIOPAUSE

    Energy Technology Data Exchange (ETDEWEB)

    Jokipii, J. R.; Kóta, J. [Department of Planetary Sciences, University of Arizona, Tucson, AZ 8572 (United States)

    2014-10-10

    We present a possible explanation for the transient increase in the galactic cosmic ray flux observed by Voyager 1 (V1) beyond the heliopause, in 2013 March. We suggest that this disturbance may be caused by a propagating disturbance in the interstellar magnetic field, of heliospheric origin. A model in which a magnetic disturbance, propagating outward from the heliosphere into the very-local interstellar plasma, affects the galactic cosmic rays is presented. We also discuss the possibility that this event is related to the plasma-wave event observed some 25 days later by the PWS experiment on V1.

  20. Du discours sur l'Autre au discours sur soi : Le Voyage en Orient de Lamartine

    OpenAIRE

    magri-mourgues, Véronique,

    2001-01-01

    International audience; L'article veut montrer comment le discours sur l'Autre, l'étranger, peut se muer en discours réflexif sur soi. Un parcours est accompli depuis les discours antérieurs au voyage jusqu'au discours pour soi en passant par les stratégies du rapprochement entre l'Autre et le Même. Le décentrement salutaire opéré par l'approche de l'Autre n'est que temporaire même s'il s'avère nécessaire pour la (re)connaissance du Même.

  1. Heliosheath Magnetic Field and Plasma Observed by Voyager 2 during 2012 in the Rising Phase of Solar Cycle 24

    Science.gov (United States)

    Burlaga, L. F.; Ness, N. F.; Richardson, J. D.; Decker, R. B.; Krimigis, S. M.

    2016-02-01

    We discuss magnetic field and plasma observations of the heliosheath made by Voyager 2 (V2) during 2012, when V2 was observing the effects of increasing solar activity following the solar minimum in 2009. The average magnetic field strength B was 0.14 nT and B reached 0.29 nT on day 249. V2 was in a unipolar region in which the magnetic polarity was directed away from the Sun along the Parker spiral 88% of the time, indicating that V2 was poleward of the heliospheric current sheet throughout most of 2012. The magnetic flux at V2 during 2012 was constant. A merged interaction region (MIR) was observed, and the flow speed increased as the MIR moved past V2. The MIR caused a decrease in the >70 MeV nuc-1 cosmic-ray intensity. The increments of B can be described by a q-Gaussian distribution with q = 1.2 ± 0.1 for daily averages and q = 1.82 ± 0.03 for hour averages. Eight isolated current sheets (“PBLs”) and four closely spaced pairs of current sheets were observed. The average change of B across the current sheets was a factor of ≈2, and B increased or decreased with equal probability. Magnetic holes and magnetic humps were also observed. The characteristic size of the PBLs was ≈6 RL, where RL is the Larmor radius of protons, and the characteristic sizes of the magnetic holes and humps were ≈38 RL and ≈11 RL, respectively.

  2. Qu'alla-t-il faire au Caire ? Le Voyage en Orient de Gérard de Nerval

    OpenAIRE

    Casajus, Dominique

    2012-01-01

    Quelle que soit la part de l'imagination dans le Voyage en Orient, que Gérard de Nerval a publié en 1851, il est possible d'y retrouver les traces du voyage qui, en 1843, l'a effectivement conduit au Caire puis à Constantinople. Le présent article part à la recherche de ces traces, en se cantonnant à la partie cairote du voyage. En même temps, on propose d'y mettre certains des procédés d'écriture de Nerval en regard avec ce qui est pratiqué aujourd'hui dans la littérature ethnographique....

  3. Communication: Probing anomalous diffusion in frequency space

    Energy Technology Data Exchange (ETDEWEB)

    Stachura, Sławomir [Centre de Biophys. Moléculaire, CNRS, Rue Charles Sadron, 45071 Orléans (France); Synchrotron Soleil, L’Orme de Merisiers, 91192 Gif-sur-Yvette (France); Kneller, Gerald R., E-mail: gerald.kneller@cnrs-orleans.fr [Centre de Biophys. Moléculaire, CNRS, Rue Charles Sadron, 45071 Orléans (France); Synchrotron Soleil, L’Orme de Merisiers, 91192 Gif-sur-Yvette (France); Université d’Orléans, Chateau de la Source-Av. du Parc Floral, 45067 Orléans (France)

    2015-11-21

    Anomalous diffusion processes are usually detected by analyzing the time-dependent mean square displacement of the diffusing particles. The latter evolves asymptotically as W(t) ∼ 2D{sub α}t{sup α}, where D{sub α} is the fractional diffusion constant and 0 < α < 2. In this article we show that both D{sub α} and α can also be extracted from the low-frequency Fourier spectrum of the corresponding velocity autocorrelation function. This offers a simple method for the interpretation of quasielastic neutron scattering spectra from complex (bio)molecular systems, in which subdiffusive transport is frequently encountered. The approach is illustrated and validated by analyzing molecular dynamics simulations of molecular diffusion in a lipid POPC bilayer.

  4. Voyager observations in the distant heliosheath: An analogy with ISEE-3 observations in the deep geomagnetic tail

    OpenAIRE

    Richardson, Ian G.

    2016-01-01

    We suggest an analogy between energetic particle and magnetic field observations made by the Voyager 1 spacecraft in the distant heliosheath at 122 AU in August 2012, and those made in the distant geomagnetic tail by the ISEE 3 spacecraft in 1982-1983, despite large differences in the time and distance scales. The analogy suggests that in August, 2012, Voyager 1 may not have moved from the anomalous cosmic ray (ACR)-dominated heliosheath into the interstellar medium but into a region equivale...

  5. An anthropology of the sea voyage - Prolegomena to an epistemology of transoceanic travel

    Directory of Open Access Journals (Sweden)

    Arnd Schneider

    2015-09-01

    Full Text Available This paper draws a distinction between an anthropology of the sea and an anthropology as sea travel – using the latter as an epistemological window to understand immigrants’ experiences of long-distance sea travel which have rarely been considered in the anthropology of immigrant societies. The paper reviews Bronislaw Malinowski’s own travel linked to some explorations of archetypical sea voyages among the Trobriand Islanders (Argonauts of the Western Pacific, 1922. In a further step, the ‘shipboard notes’ of Claude Lévi-Strauss’s Tristes Tropiques (1955 are used to consider what might have been gained if early and mid-20th century anthropologists had turned their ethnographic eye on ships, their crew and immigrants travelling on them. This paper then takes inspiration from early and mid-20th century anthropologists on sea voyages (not or only rarely related to immigrants’ travel, and applies insight from this to material from 20th century immigrants to Argentina. Though some of the empirical evidence has been published previously (Schneider 2000, it is here complemented with more recent material (from fieldwork in 2014, and interpreted in a new comparative and theoretical key.

  6. Voyager 1 in the Local Interstellar Medium: Cosmic-ray Energy Density and Ionization Rate

    Science.gov (United States)

    Cummings, A. C.; Stone, E. C.; Heikkila, B. C.; Lal, N.; Webber, W. R.; Johannesson, G.; Moskalenko, I.; Orlando, E.; Porter, T.

    2015-12-01

    We present the energy spectra of cosmic ay nuclei and electrons in the local interstellar medium (LISM) from the Cosmic Ray Subsystem on Voyager 1 (V1). We use four models of the local interstellar spectra of nuclei and one of electrons that are constrained by the observations to compute the energy density and ionization rate of atomic H in the LISM above 3 MeV for electrons and protons and above 3 MeV/nuc for nuclei with Z > 1. We find that the total cosmic-ray energy density is in the range 0.82-0.97 eV/cm3, which includes a contribution of 0.023 eV/cm3 from electrons. We find the cosmic-ray ionization rate of atomic H to be in the range 1.45-1.58 x 10-17 s-1, which is a factor of more than 10 below the cosmic-ray ionization rate in diffuse interstellar clouds based on astrochemistry methods. We discuss possible reasons for this difference. Voyager data analysis is supported by NASA Grant NNN12AA012. GALPROP development is supported by NASA Grants NNX13AC47G and NNX10AE78G.

  7. Cross and magnetic helicity in the outer heliosphere from Voyager 2 observations

    CERN Document Server

    Iovieno, M; Fraternale, F; Richardson, J D; Opher, M; Tordella, D

    2015-01-01

    Plasma velocity and magnetic field measurements from the Voyager 2 mission are used to study solar wind turbulence in the slow solar wind at two different heliocentric distances, 5 and 29 astronomical units, sufficiently far apart to provide information on the radial evolution of this turbulence. The magnetic helicity and the cross-helicity, which express the correlation between the plasma velocity and the magnetic field, are used to characterize the turbulence. Wave number spectra are computed by means of the Taylor hypothesis applied to time resolved single point Voyager 2 measurements. The overall picture we get is complex and difficult to interpret. A substantial decrease of the cross-helicity at smaller scales (over 1-3 hours of observation) with increasing heliocentric distance is observed. At 5 AU the only peak in the probability density of the normalized residual energy is negative, near -0.5. At 29 AU the probability density becomes doubly peaked, with a negative peak at -0.5 and a smaller peak at a ...

  8. Lalandes ‘Voyage de Hollande’. Het reisverslag van een astronoom, 1774

    Directory of Open Access Journals (Sweden)

    Florine Weekenstroo

    2013-01-01

    Full Text Available Lalandes ‘Voyage de Hollande’. The itinerary of an astronomer, 1774.In 1774, the French astronomer Joseph Jérôme Lefrançois de Lalande (1732–1807 visited the Dutch Republic to plea for a greater role of astronomy in navigation. At that time his Astronomie was translated into Dutch. A handwritten travelogue of his visit is preserved in the Bibliothèque de l’Institut de France in Paris. It is a brief, but fairly complete description of his journey, in which Lalande gives an impression of his visit to the cities, scientists, instrument makers and other – for the greater part – very prominent people of the Dutch Republic. This paper discusses Lalande’s experiences in the Netherlands. It shows that Lalande’s Voyage de Hollande is a unique testimony, showing how a foreign scholar experienced the Dutch Republic at the end of the eighteenth century and how he was received as scientific celebrity by the Dutch social upper class.

  9. Turbulence in the solar wind: spectra from Voyager 2 data at 5 AU

    CERN Document Server

    Fraternale, F; Iovieno, M; Opher, M; Richardson, J D; Tordella, D

    2015-01-01

    The solar wind spectral properties are far from uniformity and evolve with the increasing distance from the sun. Most of the available spectra of solar wind turbulence were computed at 1 astronomical unit, while accurate spectra on wide frequency ranges at larger distances are still few. In this paper we consider solar wind spectra derived from the data recorded by the Voyager 2 mission during 1979 at about 5 AU from the sun. Voyager 2 data are an incomplete time series with a voids/signal ratio that typically increases as the spacecraft moves away from the sun (45% missing data in 1979), making the analysis challenging. In order to estimate the uncertainty of the spectral slopes, different methods are tested on synthetic turbulence signals with the same gap distribution as V2 data. Spectra of all variables show a power law scaling with exponents between -2.1 and -1.1, depending on frequency subranges. PDFs and correlations indicate that the flow has a significant intermittency.

  10. Voyager Observations of Magnetic Fields and Cosmic Rays in the Heliosheath

    Science.gov (United States)

    Burlaga, L. F.; Ness, N. F.; Stone, E.; McDonald, F. B.

    2011-01-01

    The major features of the profile of greater than 70 MeV/nuc cosmic ray intensity (CRI) observed by Voyager 1 (VI) in the heliosheath from 2005.8-2010.24 are described by the empirical "CR-B" relation as the cumulative effect of variations of the magnetic field strength B. The CRI profile observed by Voyager 2 (V2) from 2008.60 to 2010.28 in the heliosheath is also described by the CR-B relation. On a smaller scale, of the order of a hundred days, a sequence on CRI decreases observed by V 1 during 2006 was interpreted as the effect of a propagating interplanetary shock first interacting with the termination shock, then moving past V1, and finally reflecting from the heliopause and propagating back to V1. Our observations show that the second CRI decrease in this sequence began during the passage of a "Global Merged Interaction Region" (GMIR), 40 days after the arrival of the GMIR and its possible shock. The first and third CRI decreases in the sequence were associated with local enhancements of B. The magnetic field observations associated with the second sequence of 3 cosmic ray intensity decreases observed by V 1 in 2007/2008 are more difficult to reconcile with the scenario of Webber et al. (2009) and the CR-B relation. The discrepancy might indicate the importance of latitudinal effects

  11. Charles Darwin's beagle voyage, fossil vertebrate succession, and "the gradual birth & death of species".

    Science.gov (United States)

    Brinkman, Paul D

    2010-01-01

    The prevailing view among historians of science holds that Charles Darwin became a convinced transmutationist only in the early spring of 1837, after his Beagle collections had been examined by expert British naturalists. With respect to the fossil vertebrate evidence, some historians believe that Darwin was incapable of seeing or understanding the transmutationist implications of his specimens without the help of Richard Owen. There is ample evidence, however, that he clearly recognized the similarities between several of the fossil vertebrates he collected and some of the extant fauna of South America before he returned to Britain. These comparisons, recorded in his correspondence, his diary and his notebooks during the voyage, were instances of a phenomenon that he later called the "law of the succession of types." Moreover, on the Beagle, he was following a geological research agenda outlined in the second volume of Charles Lyell's Principles of Geology, which implies that paleontological data alone could provide an insight into the laws which govern the appearance of new species. Since Darwin claims in On the Origin of Species that fossil vertebrate succession was one of the key lines of evidence that led him to question the fixity of species, it seems certain that he was seriously contemplating transmutation during the Beagle voyage. If so, historians of science need to reconsider both the role of Britain's expert naturalists and the importance of the fossil vertebrate evidence in the development of Darwin's ideas on transmutation.

  12. Mobile Game Probes

    DEFF Research Database (Denmark)

    Borup Lynggaard, Aviaja

    2006-01-01

    This paper will examine how probes can be useful for game designers in the preliminary phases of a design process. The work is based upon a case study concerning pervasive mobile phone games where Mobile Game Probes have emerged from the project. The new probes are aimed towards a specific target...... group and the goal is to specify the probes so they will cover the most relevant areas for our project. The Mobile Game Probes generated many interesting results and new issues occurred, since the probes came to be dynamic and favorable for the process in new ways....

  13. Deep atmospheric probe missions to Uranus and Neptune

    Science.gov (United States)

    Swenson, Byron L.; Wercinski, Paul F.; Reynolds, Ray T.; Mascy, Alfred C.

    1990-01-01

    The impressive results of the Voyager 2 flybys of Uranus (January 1986) and Neptune (August 1989) revealed many surprises and produced a new set of scientific questions regarding the formation and evolution of the planets, their atmospheres, the rings that surround them, and their satellite systems. A new set of intensive exploration missions to these outer planets is currently being examined by NASA and the scientific community. These missions, like Galileo to Jupiter and Cassini to Saturn, are to provide longer-term high-resolution orbital observations together with in situ atmospheric measurements. This paper will examine the feasibility of using deep atmospheric probes in connection with orbital missions to Uranus and Neptune to obtain the desired scientific measurements down to atmospheric pressure levels of at least 200 bars. The key design parameters of the atmospheric mission and system are defined, examined in some detail, and feasible options are suggested for further study.

  14. Now, voyager.

    Science.gov (United States)

    Allen, Daniel

    2008-02-01

    Diana Athill, now 90, has spent a life in books. As a writer, editor and publisher she has, as expected, a way with words, employed to great effect in A Final Farewell to Sex, published in The Guardian Weekend magazine ( http://tinyurl.com/2gg20y ).

  15. The power of space: The biopolitics of custody and care at the Lloyd Hotel, Amsterdam

    NARCIS (Netherlands)

    Minca, C.; Ong, C.E.

    2016-01-01

    This paper examines the relationship between space and violence through a biopolitical enquiry of custody and care at Amsterdam's Lloyd Hotel. The Lloyd Hotel began as a corporate established transhipment hotel serving transatlantic voyages. It was subsequently transformed into an emergency refugee

  16. Environmental Impact Specification for Direct Space Weathering of Kuiper Belt and Oort Cloud Objects

    Science.gov (United States)

    Cooper, John F.

    2010-01-01

    The Direct Space Weathering Project of NASA's Outer Planets Research Program addresses specification of the plasma and energetic particle environments for irradiation and surface chemical processing of icy bodies in the outer solar system and the local interstellar medium. Knowledge of the radiation environments is being expanded by ongoing penetration of the twin Voyager spacecraft into the heliosheath boundary region of the outer heliosphere and expected emergence within the next decade into the very local interstellar medium. The Voyager measurements are being supplemented by remote sensing from Earth orbit of energetic neutral atom emission from this boundary region by NASA's Interstellar Boundary Explorer (IBEX). Although the Voyagers long ago passed the region of the Classical Kuiper Belt, the New Horizons spacecraft will encounter Pluto in 2015 and thereafter explore one or more KBOs, meanwhile providing updated measurements of the heliospheric radiation environment in this region. Modeling of ion transport within the heliosphere allows specification of time-integrated irradiation effects while the combination of Voyager and IBEX data supports projection of the in-situ measurements into interstellar space beyond the heliosheath. Transformation of model ion flux distributions into surface sputtering and volume ionization profiles provides a multi-layer perspective for space weathering impact on the affected icy bodies and may account for some aspects of color and compositional diversity. Other important related factors may include surface erosion and gardening by meteoritic impacts and surface renewal by cryovolcanism. Chemical products of space weathering may contribute to energy resources for the latter.

  17. Voyager: Reading and Writing for Today's Adults. Levels 4, 5 and 6 Teacher's Resource Guide [and] Student Book [and] Student Workbook [and] Puzzles [and] Vocabulary Workbook. Voyager Placement Tool for Levels Foundation-6 Student Booklet [and] Teacher Scoring Guide.

    Science.gov (United States)

    1999

    This document contains the 15 publications constituting the third stage of the Voyager program, which is a four-stage program that utilizes contemporary content and instructional approaches to teach the reading, writing, critical thinking, and communication skills that adults need in today's world and to take adult learners from the beginning…

  18. Voyager: Reading and Writing for Today's Adults. Foundation and Level 1 Teacher's Resource Guide [and] Student Book [and] Student Workbook [and] Puzzles [and] Vocabulary Workbook. Voyager Placement Tool for Levels Foundation-6 Student Booklet [and] Teacher Scoring Guide.

    Science.gov (United States)

    1999

    This document contains the 11 publications constituting the first stage of the Voyager program, which is a four-stage program that utilizes contemporary content and instructional approaches to teach the reading, writing, critical thinking, and communication skills that adults need in today's world and to take adult learners from the beginning…

  19. Voyager: Reading and Writing for Today's Adults. Levels 2 and 3 Teacher's Resource Guide [and] Student Book [and] Student Workbook [and] Puzzles [and] Vocabulary Workbook. Voyager Placement Tool for Levels Foundation-6 Student Booklet [and] Teacher Scoring Guide.

    Science.gov (United States)

    1999

    This document contains the 11 publications constituting the second stage of the Voyager program, which is a four-stage program that utilizes contemporary content and instructional approaches to teach the reading, writing, critical thinking, and communication skills that adults need in today's world and to take adult learners from the beginning…

  20. ChemVoyage: A Web-Based, Simulated Learning Environment with Scaffolding and Linking Visualization to Conceptualization

    Science.gov (United States)

    McRae, Christopher; Karuso, Peter; Liu, Fei

    2012-01-01

    The Web is now a standard tool for information access and dissemination in higher education. The prospect of Web-based, simulated learning platforms and technologies, however, remains underexplored. We have developed a Web-based tutorial program (ChemVoyage) for a third-year organic chemistry class on the topic of pericyclic reactions to…

  1. The representations of the overseas world in the De Bry collection of voyages (1590-1634). - Pbk ed.

    NARCIS (Netherlands)

    van Groesen, M.

    2012-01-01

    This book deals with the De Bry collection of voyages, one of the most monumental publications of Early Modern Europe. It analyzes the textual and iconographic changes the De Bry publishing family made to travel accounts describing Asia, Africa and the New World. It discusses this editorial strategy

  2. America abridged: Matthaeus Merian, Johann Ludwig Gottfried, and the apotheosis of the De Bry collection of voyages

    NARCIS (Netherlands)

    van Groesen, M.

    2011-01-01

    In 1631, Matthaeus Merian and Johann Ludwig Gottfried published a one-volume abridgment of the monumental America series issued by Theodor De Bry and his two sons. Historia Antipodum can be considered the apotheosis of the collection of voyages to the New World. This article argues that the abridgme

  3. Properties of Ultrasound Probes

    OpenAIRE

    Rusina, M.

    2015-01-01

    This work deals with the measurement properties of ultrasound probes. Ultrasound probes and their parameters significantly affect the quality of the final image. In this work there are described the possibility of measuring the spatial resolution, sensitivity of the probe and measuring the length of the dead zone. Ultrasound phantom ATS Multi Purpose Phantom Type 539 was used for measurements.

  4. The Van Allen Probes mission

    CERN Document Server

    Burch, James

    2014-01-01

    This collection of articles provides broad and detailed information about NASA’s Van Allen Probes (formerly known as the Radiation Belt Storm Probes) twin-spacecraft Earth-orbiting mission. The mission has the objective of achieving predictive understanding of the dynamic, intense, energetic, dangerous, and presently unpredictable belts of energetic particles that are magnetically trapped in Earth’s space environment above the atmosphere. It documents the science of the radiation belts and the societal benefits of achieving predictive understanding. Detailed information is provided about the Van Allen Probes mission design, the spacecraft, the science investigations, and the onboard instrumentation that must all work together to make unprecedented measurements within a most unforgiving environment, the core of Earth’s most intense radiation regions.
 This volume is aimed at graduate students and researchers active in space science, solar-terrestrial interactions and studies of the up...

  5. Voyager Observations in the Distant Heliosheath - an Analogy With ISEE-3 Observations in theDeep Geomagnetic Tail

    Science.gov (United States)

    Richardson, Ian

    2015-04-01

    We suggest an analogy between energetic particle and magnetic field observations made by the Voyager 1 spacecraft in the distant heliosheath at 122 AU in August 2012 and those made in the distant geomagnetic tail by the Energetic Particle Anisotropy Spectrometer (EPAS) on the ISEE 3 spacecraft in 1982-1983, including remarkable similarities in the behavior of the energetic particle intensities and anisotropies despite large differences in the time and distance scales.The analogy suggests that Voyager 1 may have moved not into the interstellar medium from heliosheath but instead into a region equivalent to the “lobes” of the geomagnetic tail. This region may be composed of heliospheric field lines which have reconnected with the interstellar medium beyond the spacecraft and so are open to the entry of cosmic rays, while heliospheric particles (e.g., Anomalous Cosmic Rays) are free to escape, leaving only a weak population of large pitch-angle ACRs with “pancake” distributions similar to those also seen by ISEE 3 in the lobes of the tail. If this is the case, the actual heliopause (equivalent to the magnetopause), where the ambient interstellar medium is entered, lies beyond the current distance of Voyager 1.Temporary variations in the energetic particle and magnetic field intensities at Voyager over a period of around 27 days prior to the final boundary crossing are interpreted as the boundary twice approaching Voyager 1 and then retreating Sunward before the final crossing occurred. Similar features were frequently observed in the deep tail due to tail dynamics and “flapping” in the solar wind. The 27 day interval suggests that rotation of the heliosphere may have contributed to this boundary motion.Energetic particles in the tail are accelerated by reconnection in the plasma sheet which can lead to the formation of plasmoids. Both are elements of some recent models of the heliopause.

  6. The Interstellar Ethics of Self-Replicating Probes

    Science.gov (United States)

    Cooper, K.

    Robotic spacecraft have been our primary means of exploring the Universe for over 50 years. Should interstellar travel become reality it seems unlikely that humankind will stop using robotic probes. These probes will be able to replicate themselves ad infinitum by extracting raw materials from the space resources around them and reconfiguring them into replicas of themselves, using technology such as 3D printing. This will create a colonising wave of probes across the Galaxy. However, such probes could have negative as well as positive consequences and it is incumbent upon us to factor self-replicating probes into our interstellar philosophies and to take responsibility for their actions.

  7. Carnet de voyage au cœur de la justice internationale

    OpenAIRE

    Rubio, François

    2009-01-01

    Au moment où la justice internationale lance courageusement, et pour la première fois, un mandat d’arrêt international contre un chef d’État en exercice pour « crimes de guerre et crimes contre l’humanité », le livre de Stéphanie Maupas est salutaire. Loin de constituer une leçon de droit international ou une réflexion théorique, il se veut un carnet de voyage au cœur d’un système nouveau, celui du droit pénal international. Dans celui-ci, le balancier oscille entre les « grands de ce monde »...

  8. One true threesome: Reconciling canon and fan desire in Star Trek: Voyager

    Directory of Open Access Journals (Sweden)

    Bridget Kies

    2011-09-01

    Full Text Available Fan-written stories that involve three-way relationships among the characters Tom Paris, Harry Kim, and B'Elanna Torres from Star Trek: Voyager capitalize on the homosocial bond between Paris and Kim and the canonical relationship between Paris and Torres to create a queer triangular relationship in which characterization, sexuality, and desire are all reoriented from the canon. Some of these stories relegate the nontraditional relationship to something approximating heteronormativity; in these instances, the story mirrors the canon in its often undesirable depiction of domesticity. In other stories, the triad moves away from dominant cultural expectations like marriage and children; in these stories, the triad seems to endure happily. The key to the stability of the erotic triangle therefore shifts the relationship or relationships away from the burden of hegemonic values, both in canon and in fan fiction.

  9. Photo Essay: Notes on “The Voyage of the USS Juniata (1883–1885”

    Directory of Open Access Journals (Sweden)

    John Dowling

    2013-06-01

    Full Text Available The images included in the June 2013 Cross-Currents photo essay, “The Voyage of the USS Juniata (1883–1885,” are digital scans made from a set of five-by-eight-inch glass plate negatives depicting scenes from a three-year (1883–1885 naval expedition to the Far East by the USS Juniata. The photographer was Asa M. Mattice, an officer on board (figure 1. Mattice, a native of New York State, graduated from the U.S. Naval Academy at the head of his class as a cadet engineer in 1874 and was later appointed to the teaching staff at Annapolis. He served on the USS Juniata beginning on November 30, 1882, when the ship departed from New York to join five other ships at the Asiatic Squadron.

  10. Voyage aux sources des mille et une heures, contes péruviens

    OpenAIRE

    Bosquet, Marie-Françoise; Daoulas, Régine

    2007-01-01

    Porté par une conjonction d’événements dans l’actualité de ce xviiie siècle (attrait des grands voyages de découverte, querelle scientifique entre partisans des astronomes Newton et Cassini provoquant l’expédition de La Condamine vers le Nouveau Monde), T.-S. Gueullette choisit d’installer le récit-cadre des Mille et Une Heures dans un Pérou mythologique, celui de l’Inca Yahuar Huacac et de son fils Viracocha. D’une part, T.-S. Gueullette se coule dans l’air du temps et répond au goût des sal...

  11. One true threesome: Reconciling canon and fan desire in Star Trek: Voyager

    Directory of Open Access Journals (Sweden)

    Bridget Kies

    2011-11-01

    Full Text Available Fan-written stories that involve three-way relationships among the characters Tom Paris, Harry Kim, and B'Elanna Torres from Star Trek: Voyager capitalize on the homosocial bond between Paris and Kim and the canonical relationship between Paris and Torres to create a queer triangular relationship in which characterization, sexuality, and desire are all reoriented from the canon. Some of these stories relegate the nontraditional relationship to something approximating heteronormativity; in these instances, the story mirrors the canon in its often undesirable depiction of domesticity. In other stories, the triad moves away from dominant cultural expectations like marriage and children; in these stories, the triad seems to endure happily. The key to the stability of the erotic triangle therefore shifts the relationship or relationships away from the burden of hegemonic values, both in canon and in fan fiction.

  12. Magnetic field observations as Voyager 1 entered the heliosheath depletion region.

    Science.gov (United States)

    Burlaga, L F; Ness, N F; Stone, E C

    2013-07-12

    Magnetic fields measured by Voyager 1 (V1) show that the spacecraft crossed the boundary of an unexpected region five times between days 210 and ~238 in 2012. The magnetic field strength B increased across this boundary from ≈0.2 to ≈0.4 nanotesla, and B remained near 0.4 nanotesla until at least day 270, 2012. The strong magnetic fields were associated with unusually low counting rates of >0.5 mega-electron volt per nuclear particle. The direction of B did not change significantly across any of the five boundary crossings; it was very uniform and very close to the spiral magnetic field direction, which was observed throughout the heliosheath. The observations indicate that V1 entered a region of the heliosheath (the heliosheath depletion region), rather than the interstellar medium.

  13. Strong Temporal Variation Over One Saturnian Year: From Voyager to Cassini

    Science.gov (United States)

    Li, Liming; Achterberg, Richard K.; Conrath, Barney J.; Gierasch, Peter J.; Smith, Mark A.; Simon-Miller, Amy A.; Nixon, Conor A.; Orton, Glenn S.; Flasar, F. Michael; Jiang, Xun; hide

    2013-01-01

    Here we report the combined spacecraft observations of Saturn acquired over one Saturnian year (approximately 29.5 Earth years), from the Voyager encounters (1980-81) to the new Cassini reconnaissance (2009-10). The combined observations reveal a strong temporal increase of tropic temperature (approximately 10 Kelvins) around the tropopause of Saturn (i.e., 50 mbar), which is stronger than the seasonal variability (approximately a few Kelvins). We also provide the first estimate of the zonal winds at 750 mbar, which is close to the zonal winds at 2000 mbar. The quasi-consistency of zonal winds between these two levels provides observational support to a numerical suggestion inferring that the zonal winds at pressures greater than 500 mbar do not vary significantly with depth. Furthermore, the temporal variation of zonal winds decreases its magnitude with depth, implying that the relatively deep zonal winds are stable with time.

  14. The Next Generation Library Catalog: A Comparative Study of the OPACs of Koha, Evergreen, and Voyager

    Directory of Open Access Journals (Sweden)

    Sharon Q. Yang

    2010-09-01

    Full Text Available Open source has been the center of attention in the library world for the past several years. Koha and Evergreen are the two major open-source integrated library systems (ILSs, and they continue to grow in maturity and popularity. The question remains as to how much we have achieved in open-source development toward the next-generation catalog compared to commercial systems. Little has been written in the library literature to answer this question. This paper intends to answer this question by comparing  the next-generation features of the OPACs of two open-source ILSs (Koha and Evergreen and one proprietary ILS (Voyager’s WebVoyage.

  15. Voyager measurements of hydrogen Lyman-α diffuse emission from the Milky Way.

    Science.gov (United States)

    Lallement, Rosine; Quémerais, Eric; Bertaux, Jean-Loup; Sandel, Bill R; Izmodenov, Vlad

    2011-12-23

    Doppler-shifted hydrogen Lyman-alpha (Lyα) emission from galaxies is currently measured and used in cosmology as an indicator of star formation. Until now, the Milky Way emission has not been detected, owing to far brighter local sources, including the H (hydrogen) glow, i.e., solar Lyα radiation backscattered by interstellar atoms that flow within the solar system. Because observations from the Voyager spacecraft, now leaving the heliosphere, are decreasingly affected by the H glow, the ultraviolet spectrographs are detecting Lyα diffuse emission from our Galaxy. The surface brightness toward nearby star-forming regions is about 3 to 4 rayleighs. The escape fraction of the radiation from the brightest H II regions is on the order of 3% and is highly spatially variable. These results will help in constraining models of Lyα radiation transfer in distant galaxies.

  16. Probing zeolites by vibrational spectroscopies.

    Science.gov (United States)

    Bordiga, Silvia; Lamberti, Carlo; Bonino, Francesca; Travert, Arnaud; Thibault-Starzyk, Frédéric

    2015-10-21

    This review addresses the most relevant aspects of vibrational spectroscopies (IR, Raman and INS) applied to zeolites and zeotype materials. Surface Brønsted and Lewis acidity and surface basicity are treated in detail. The role of probe molecules and the relevance of tuning both the proton affinity and the steric hindrance of the probe to fully understand and map the complex site population present inside microporous materials are critically discussed. A detailed description of the methods needed to precisely determine the IR absorption coefficients is given, making IR a quantitative technique. The thermodynamic parameters of the adsorption process that can be extracted from a variable-temperature IR study are described. Finally, cutting-edge space- and time-resolved experiments are reviewed. All aspects are discussed by reporting relevant examples. When available, the theoretical literature related to the reviewed experimental results is reported to support the interpretation of the vibrational spectra on an atomic level.

  17. Magnetic Field Strength Fluctuations in the Heliosheath: Voyager 1 Observations During 2009

    Science.gov (United States)

    Brulaga, L. F.; Ness, N. F.

    2012-01-01

    We analyze the microscale fluctuations of the magnetic field strength B on a scale of several hours observed by Voyager1 (V1) in the heliosheath during 2009. The microscale fluctuations of B range from coherent to stochastic structures. The amplitude of microscale fluctuations of B during 1 day is measured by the standard deviation (SD) of 48 s averages of B. The distribution of the daily values of SD is lognormal. SD(t) from day of year (DOY) 1 to 331, 2009, is very intermittent. SD(t) has a 1/f or "pink noise" spectrum on scales from 1 to 100 days, and it has a broad multifractal spectrum f(alpha) with 0.57 less than or equal to alpha less than or equal to 1.39. The time series of increments SD(t + tau) -- SD(t) has a pink noise spectrum with alpha(1) = 0.88 plus or minus 0.14 on scales from 1 to 100 days. The increments have a Tsallis (q-Gaussian) distribution on scales from 1 to 165 days, with an average q = 1.75 plus or minus 0.12. The skewness S and kurtosis K have Gaussian and lognormal distributions, respectively. The largest spikes in K(t) and S(t) are often associated with a change in B across a data gap and with identifiable physical structures. The "turbulence" observed by V1 during 2009 was weakly compressible on average but still very intermittent, highly variable, and highly compressible at times. The turbulence observed just behind the termination shock by Voyager 2 was twice as strong. These observations place strong constraints on any model of turbulence in the heliosheath.

  18. Leadership in Space: Selected Speeches of NASA Administrator Michael Griffin, May 2005 - October 2008

    Science.gov (United States)

    Griffin, Michael

    2008-01-01

    Speech topics include: Leadership in Space; Space Exploration: Real and Acceptable Reasons; Why Explore Space?; Space Exploration: Filling up the Canvas; Continuing the Voyage: The Spirit of Endeavour; Incorporating Space into Our Economic Sphere of Influence; The Role of Space Exploration in the Global Economy; Partnership in Space Activities; International Space Cooperation; National Strategy and the Civil Space Program; What the Hubble Space Telescope Teaches Us about Ourselves; The Rocket Team; NASA's Direction; Science and NASA; Science Priorities and Program Management; NASA and the Commercial Space Industry; NASA and the Business of Space; American Competitiveness: NASA's Role & Everyone's Responsibility; Space Exploration: A Frontier for American Collaboration; The Next Generation of Engineers; System Engineering and the "Two Cultures" of Engineering; Generalship of Engineering; NASA and Engineering Integrity; The Constellation Architecture; Then and Now: Fifty Years in Space; The Reality of Tomorrow; and Human Space Exploration: The Next 50 Years.

  19. Backpackers et carnets de voyage, récit biographique d’une expérience itinérante

    OpenAIRE

    Courant, Stéphane

    2014-01-01

    Travaillant depuis plusieurs années sur les écritures de voyage, je propose dans cet article une analyse transversale des carnets tenus par des backpackers. Objet polymorphe, à la fois écritures ordinaires du voyage et écritures laissant entrevoir une intimité du voyageur, le carnet de voyage nécessite la mise en place d’une méthodologie spécifique –– observation participante — pour son obtention ou tout simplement pour sa consultation. Au-delà des caractéristiques significatives de la popula...

  20. Thermoelectric power conversion in space

    Science.gov (United States)

    Awaya, Henry I.; Ewell, Richard; Nesmith, Bill; Vandersande, James

    1990-01-01

    A radiatively-heated multicouple for use in the next generation of radioisotope thermoelectric generator (RTG) will employ 20 individual couples within a single cell, so that 40 n- and p-semiconductor legs will be interconnected in series. At the hot end of the RTG, the legs will be electrically interconnected using silicon molybdenum; on the cold side, the legs are interconnected by tungsten. The entire cell is then mechanically attached to a radiator, which conducts heat away and radiates it into space. Deep-space applications will use RTGs developed for vacuum operation; thermoelectric converter power systems using a unicouple configuration have flown on such missions as Pioneers 10 and 11, which used lead telluride thermoelectric converters, and Voyagers I and II, which used silicon germanium-based thermoelectrics.

  1. Exact probes of orientifolds

    CERN Document Server

    Fiol, Bartomeu; Torrents, Genis

    2014-01-01

    We compute the exact vacuum expectation value of circular Wilson loops for Euclidean ${\\cal N}=4$ super Yang-Mills with $G=SO(N),Sp(N)$, in the fundamental and spinor representations. These field theories are dual to type IIB string theory compactified on $AdS_5\\times {\\mathbb R} {\\mathbb P}^5$ plus certain choices of discrete torsion, and we use our results to probe this holographic duality. We first revisit the LLM-type geometries having $AdS_5\\times {\\mathbb R} {\\mathbb P}^5$ as ground state. Our results clarify and refine the identification of these LLM-type geometries as bubbling geometries arising from fermions on a half harmonic oscillator. We furthermore identify the presence of discrete torsion with the one-fermion Wigner distribution becoming negative at the origin of phase space. We then turn to the string world-sheet interpretation of our results and argue that for the quantities considered they imply two features: first, the contribution coming from world-sheets with a single crosscap is closely ...

  2. Lessons learned from planetary entry probe missions

    Science.gov (United States)

    Niemann, Hasso; Atreya, Sushil K.; Kasprzak, Wayne

    technology will also play an important role. The emergence over the past twenty years of Micro-electro-mechanical Systems (MEMS), utilizing lithographic semiconductor fabrication techniques to produce instrument systems in miniature, holds great promise for application to spaceflight. For example, a highly miniaturized, high performance and low-power gas chromatograph mass spectrometer would enormously benefit entry probe missions, allowing, for example, parallel measurements (e.g., multiple simultaneous gas chromatographic and direct atmospheric measurements). Such an instrument would also enable mass spectrometry on board small multiple entry probes. The challenge facing us in the development of MEMS based instruments is to move beyond the proof-of-concept, where research dollars tend to focus, and carry out the detailed work of developing high performance flight instrument systems on a chip which reach the required high technical readiness level for space flight.

  3. Slingshot Dynamics for Self Replicating Probes and the Effect on Exploration Timescales

    CERN Document Server

    Nicholson, Arwen

    2013-01-01

    Interstellar probes can carry out slingshot manoeuvres around the stars they visit, gaining a boost in velocity by extracting energy from the star's motion around the Galactic Centre. These maneouvres carry little to no extra energy cost, and in previous work it has been shown that a single Voyager-like probe exploring the galaxy does so 100 times faster when carrying out these slingshots than when navigating purely by powered flight (Forgan et al. 2012). We expand on these results by repeating the experiment with self-replicating probes. The probes explore a box of stars representative of the local Solar neighbourhood, to investigate how self-replication affects exploration timescales when compared with a single non-replicating probe. We explore three different scenarios of probe behaviour: i) standard powered flight to the nearest unvisited star (no slingshot techniques used), ii) flight to the nearest unvisited star using slingshot techniques, and iii) flight to the next unvisited star that will give the m...

  4. Conductivity Probe after Trench-Bottom Placement

    Science.gov (United States)

    2008-01-01

    Needles of the thermal and conductivity probe on NASA's Phoenix Mars Lander were positioned into the bottom of a trench called 'Upper Cupboard' during Sol 86 (Aug. 21, 2008), or 86th Martian day after landing. This image of the conductivity probe after it was raised back out of the trench was taken by Phoenix's Robotic Arm Camera. The conductivity probe is at the wrist of the robotic arm's scoop. The probe measures how fast heat and electricity move from one needle to an adjacent one through the soil or air between the needles. Conductivity readings can be indicators about water vapor, water ice and liquid water. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  5. Phoenix Conductivity Probe Inserted into Martian Soil

    Science.gov (United States)

    2008-01-01

    NASA's Phoenix Mars Lander inserted the four needles of its thermal and conductivity probe into Martian soil during the 98th Martian day, or sol, of the mission and left it in place until Sol 99 (Sept. 4, 2008). The Robotic Arm Camera on Phoenix took this image on the morning of Sol 99 while the probe's needles were in the ground. The science team informally named this soil target 'Gandalf.' The thermal and conductivity probe measures how fast heat and electricity move from one needle to an adjacent one through the soil or air between the needles. Conductivity readings can be indicators about water vapor, water ice and liquid water. The probe is part of Phoenix's Microscopy, Electrochemistry and Conductivity suite of instruments. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  6. Health physics innovations developed during Cassini for future space applications

    Science.gov (United States)

    Nickell, Rod; Rutherford, Theresa; Marmaro, George

    1999-01-01

    There has been a long history of space missions involving Space Nuclear Auxiliary Power (SNAP) devices starting with the Transit 4A Spacecraft (1961), on through the Apollo, Pioneer, Viking, Voyager, Galileo, Ulysses, Mars Pathfinder, and most recently, Cassini (1997). All of these Major Radiological Source (MRS) missions were processed at the Kennedy Space Center/Cape Canaveral Air Station (KSC/CCAS) Launch Site in full compliance with program and regulatory requirements. The cumulative experience gained supporting these past missions has led to significant innovations which will be useful for bench-marking future MRS ground processing.

  7. Gravity and On-Shell Probe Actions

    CERN Document Server

    Ferrari, Frank

    2016-01-01

    In any gravitational theory and in a wide class of background space-times, we argue that there exists a simple, yet profound, relation between the on-shell Euclidean gravitational action and the on-shell Euclidean action of probes. The probes can be, for instance, charged particles or branes. The relation is tightly related to the thermodynamic nature of gravity. We provide precise checks of the relation in several examples, which include both asymptotically flat and asymptotically AdS space-times, with particle, D-brane and M-brane probes. Perfect consistency is found in all cases, including in a highly non-trivial example including \\alpha'-corrections.

  8. Gravity and on-shell probe actions

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, Frank [Université libre de Bruxelles (ULB) and International Solvay Institutes,Service de Physique Théorique et Mathématique,Campus de la Plaine, CP 231, B-1050 Bruxelles (Belgium); Theoretical Physics Department, CERN,CH-1211 Genève (Switzerland); Rovai, Antonin [Département de Physique Théorique, Université de Genève,24, quai Ansermet, CH-1211 Genève 4 (Switzerland); Université libre de Bruxelles (ULB) and International Solvay Institutes,Service de Physique Théorique et Mathématique,Campus de la Plaine, CP 231, B-1050 Bruxelles (Belgium); Center for Theoretical Physics, Massachusetts Institute of Technology,77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Arnold Sommerfeld Center for Theoretical Physics, Ludwig-Maximilians-Universität München,Theresienstrasse 37, D-80333 München (Germany)

    2016-08-08

    In any gravitational theory and in a wide class of background space-times, we argue that there exists a simple, yet profound, relation between the on-shell Euclidean gravitational action and the on-shell Euclidean action of probes. The probes can be, for instance, charged particles or branes. The relation is tightly related to the thermodynamic nature of gravity. We provide precise checks of the relation in several examples, which include both asymptotically flat and asymptotically AdS space-times, with particle, D-brane and M-brane probes. Perfect consistency is found in all cases, including in a highly non-trivial example including α{sup ′}-corrections.

  9. Atom probe crystallography

    National Research Council Canada - National Science Library

    Gault, Baptiste; Moody, Michael P; Cairney, Julie M; Ringer, Simon P

    2012-01-01

    This review addresses new developments in the emerging area of "atom probe crystallography", a materials characterization tool with the unique capacity to reveal both composition and crystallographic...

  10. On the Cell Probe Complexity of Membership and Perfect Hashing

    DEFF Research Database (Denmark)

    Pagh, Rasmus

    2001-01-01

    We study two fundamental static data structure problems, membership and perfect hashing, in Yao's cell probe model. The first space and bit probe optimal worst case upper bound is given for the membership problem. We also give a new efficient membership scheme where the query algorithm makes just...

  11. The Plasma Depletion Layer Beyond the Heliopause: Evidence, Implications, and Predictions for Voyager 2 and New Horizons

    Science.gov (United States)

    Cairns, Iver H.; Fuselier, S. A.

    2017-01-01

    A plasma depletion layer (PDL) is predicted beyond the heliopause, analogous to the PDLs observed sunwards of planetary magnetopauses: draping of interstellar medium (ISM) magnetic field lines over the heliopause should increase the magnetic field strength and, perpendicular ion temperature, cause density depletions by allowing plasma ions (and electrons) with large parallel temperatures to escape along {\\boldsymbol{B}}, and increase the temperature anisotropy until limited by wave instabilities. Published Voyager 1 magnetometer and plasma wave data provide strong evidence for the coupled magnetic amplification (≈ 30 % ) and density depletion (≈ 50 % ) expected for a weak PDL. The predicted reduction in parallel temperature is ≈ 50 % . The locations on the sky of the PDL and the points on the heliopause of maximum magnetic draping and total pressure are predicted using the ISM magnetic field direction obtained from the Interstellar Boundary Explorer (IBEX) ribbon. The IBEX ribbon overlies the former, as expected, while the latter lies within the ridge of maximum, non-ribbon, globally distributed flux. The PDL should be strongest along the ISM field line passing through these points and the Sun–ISM velocity vector. Based on their trajectories, Voyager 2 and New Horizons should observe a much stronger PDL (stronger magnetic amplification, density depletion, and changes in temperature) than Voyager 1. Finally, the reduced cosmic ray fluxes observed near 90° pitchangle by Voyager 1 beyond the heliopause appear qualitatively consistent with wave–particle interactions transferring perpendicular particle energy to parallel energy where the PDL is strong, followed by magnetic focusing as particles propagate into weaker magnetic field regions.

  12. Comparison of the effects of different statins and doses on lipid levels in patients with diabetes: results from VOYAGER.

    Science.gov (United States)

    Karlson, B W; Barter, P J; Palmer, M K; Lundman, P; Nicholls, S J

    2012-09-01

    Diabetes mellitus is a well-known risk factor for cardiovascular disease, and brings an increased risk of vascular events and a higher mortality rate. Treatment guidelines recommend statins in patients with diabetes, with low-density lipoprotein cholesterol (LDL-C) targets of 100 mg dl(-1) (∼2.5 mmol l(-1)), and 80 (∼2.0 mmol l(-1)) or 70 mg dl(-1) (∼1.8 mmol l(-1)) in especially high-risk patients. The current study used the VOYAGER (an indiVidual patient data-meta-analysis Of statin therapY in At risk Groups: Effects of Rosuvastatin, atorvastatin, and simvastatin) database to characterise effects of rosuvastatin, atorvastatin and simvastatin in different doses on lipid levels in diabetes patients. The VOYAGER database included individual patient data from 37 studies involving comparisons of rosuvastatin with either atorvastatin or simvastatin. Of the 32 258 patients included, 8859 (27.5%) had diabetes. Rosuvastatin appeared to be the most efficacious of the three statins, both for lowering LDL-C and for reaching a target level of VOYAGER results. This meta-analysis of 8859 patients with diabetes mellitus shows favourable effects on lipids with the three statins studied, in line with results for the overall VOYAGER population. The importance of using an effective statin at an effective dose to reach treatment goals for such high-risk patients is evident. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Investment Invitation——Introduction of ZhengHe s Voyage 600th Anniversary for Making Business Items

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    In order to mark ZhengHe's voyage of adventure,commend the greal ethos of patriotism which can be explained as solidarity,peace- loving and diligence,boost up Chinese self-confidence and pride, intensify the education of navigation and ocean knowledge,enhance our native consciousness of ocean,China Business Monthly,Beijing XingJiYuanHang Cultural Communication Center and American. Diamond King International Group plan to carry out the following three particular and significant items:

  14. Advanced Technology Cloud Particle Probe for UAS Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase II SPEC will design, fabricate and flight test a state-of-the-art combined cloud particle probe called the Hawkeye. Hawkeye is the culmination of two...

  15. Pioneer Jupiter orbiter probe mission 1980, probe description

    Science.gov (United States)

    Defrees, R. E.

    1974-01-01

    The adaptation of the Saturn-Uranus Atmospheric Entry Probe (SUAEP) to a Jupiter entry probe is summarized. This report is extracted from a comprehensive study of Jovian missions, atmospheric model definitions and probe subsystem alternatives.

  16. Evaluation of radiation interference in the Voyager Sun Sensor's cadmium sulfide detector

    Science.gov (United States)

    Clarke, T. C.; Divita, E. L.

    1978-01-01

    The simulation of radiation interference effects and the results of a radiation interference test on two Voyager Sun Sensor prototype detector assemblies are reported. The derivation of test levels and requirements are discussed and show that cobalt 60 gamma radiation is an effective and practical simulator of the ionization dose rate effects induced by high-energy electron flux incident on the spacecraft at a rate of 3.7 x 10 to the 8th e/sq cm-sec (10 rad(Si)/s) during closest approach to Jupiter. The test results provide information that is used to confirm an analytic correlation, and to predict satisfactory performance of a spacecraft sun sensing device having stringent angular resolution requirements. The measured detector response shows that at dose rates incident on the detector elements of 2 rad(Si)/sec, which is four times that expected during Jupiter encounter, the radiation-induced angle error is almost an order of magnitude less than that allowed by the acceptance criteria.

  17. Micron-Sized Particles Detected in the Vicinity of Jupiter by the Voyager Plasma Wave Instruments

    Science.gov (United States)

    Tsintikidis, D.; Gurnett, D. A.; Kurth, W. S.; Granroth, L. J.

    1996-01-01

    Wideband waveform data obtained by the plasma wave instruments onboard the Voyager 1 and 2 spacecraft have been used to study micron-sized dust particles in the vicinity of Jupiter. The technique used was developed during the flybys of Saturn, Uranus, and Neptune, and makes use of the fact that a particle striking the spacecraft at 10-20 km/s causes a voltage pulse in the plasma wave receiver. The waveform of the voltage pulse is much different than the waveform of plasma waves and provides a highly reliable method of detecting micron-sized dust particles. Although the dust impact rate observed in the vicinity of Jupiter is much lower than the rates at Saturn, Uranus, and Neptune, the particles are easily detectable. Approximately 1200 48-second frames of wideband waveform data were examined in the vicinity of Jupiter. Dust impact signatures were found in approximately 20% of these frames. The peak impact rates are about 1 impact per second, and the peak number densities are about 10(exp -5) m(exp -3). Most of the impacts occurred near the equatorial plane at radial distances less than about 35 R(sub j) from Jupiter. Analysis of the detection threshold indicates that the particles have masses greater than 10(exp -11) g, which corresponds to particles with diameters of a few micrometers or larger.

  18. Uses of wonder in popular science: Cosmos: A Personal Voyage and the origin of life

    Science.gov (United States)

    Helsing, Daniel

    2016-10-01

    This paper analyses the use of wonder in the TV-series Cosmos: A Personal Voyage (1980). Popular science has been studied extensively (e.g. Broks 2006; Leane 2007; Perrault 2013), and wonder has been studied moderately (e.g. Daston & Park 1998; Fuller 2006; Vasalou 2015). However, there are very few studies of wonder in popular science. This paper explores how and why wonder is used in Cosmos, with the wider aim of understanding uses of wonder in popular science. The studies that discuss wonder in popular science (Fahnestock 1986; Perrault 2013) argue that wonder is used to enthuse the audience about science, but they do not discuss why wonder has this ability, nor whether wonder has other functions. This paper argues that Fuller's (2006) psychological and evolutionary account of wonder can elucidate why wonder has the ability to enthuse; it discerns three senses of 'wonder' (related to objects, emotions and attitudes); and it discusses other functions of wonder (existential, aesthetic and ethical). Due to the centrality of astrobiological questions in Cosmos, this paper also highlights the relation of these questions to the senses and functions of wonder in Cosmos.

  19. Transcending Voyager: A Deeper Look at Neptune's Ring-Moon System

    Science.gov (United States)

    Showalter, Mark

    2004-07-01

    We will use the High Resolution Channel {HRC} of ACS to study the inner rings, arcs and moons of Neptune with a sensitivity that exceeds that achieved by Voyager 2 during its 1989 flyby. Our study will reveal any moons down to V magnitude 25.5, to address a peculiar truncation in the size distribution of inner moons and to look for the "shepherds" and source bodies for Neptune's dusty rings. {For comparison, Neptune's smallest known moon is Naiad, at magnitude 23.9}. Recent ground-based studies show that the mysterious arcs in the Adams Ring continue to shift and change, and may be fading away entirely. We will obtain the visual-band data uniquely necessary to determine whether the arcs are fading. Long-term monitoring of the arcs at high resolution and sensitivity will reveal their gradual changes more clearly and enable us to assess the role of Galatea, whose resonances are widely believed to confine the arcs.

  20. Plasma pressure in the environment of Jupiter, inferred from Voyager 1 magnetometer observations

    Science.gov (United States)

    Caudal, G.; Connerney, J. E. P.

    1989-11-01

    A model combining the internal magnetic field with a self-consistent model of the Jovian magnetodisc was fitted to the Voyager 1 Jovian magnetic field data by means of a generalized inverse technique. The model parameters included the internal field spherical harmonic coefficients as well as with parameters describing the plasma distribution in the magnetosphere. Assuming that the pressure in the middle and outer magnetosphere is related to the unit flux tube volume V through PV exp gamma = const, the model fit yielded a value of 0.88 for gamma. If the hot (30 keV) plasma is transported adiabatically inward under the interchange instability triggered by centrifugal force of the heavy torus ions, losses are not sufficient to account for such a low value of gamma beyond L = 10. Closer to the planet, as the outer edge of the Io plasma torus is approached, PV exp gamma is found to decrease inward, as expected from the particle measurements, which identified an inner boundary of the particle fluxes in that region. With the present stage of the development of magnetodisc models, secular variations of the internal field still remain difficult to estimate.

  1. L’improvisation : une invitation à voyager en classe de FLE

    Directory of Open Access Journals (Sweden)

    Marie-Noëlle Cocton

    2015-04-01

    Full Text Available L’improvisation en didactique du français langue étrangère est, après plus d’une cinquantaine d’années d’existence, une pratique de classe aujourd’hui délaissée par les enseignants qui en ont peur ou la connaissent mal. Préconisée par le BELC dès les années 70, choisie dans les manuels de FLE pour ses bienfaits pédagogiques (Caré : 1989, elle est, depuis peu, considérée par la majorité des ouvrages périphériques liés à la didactique de la pratique théâtrale, comme une « technique » visant à communiquer autrement. L’objectif de cet article est de faire un état des lieux de la notion d’improvisation et d’expliquer comment elle s’insère dans un dispositif pédagogique invitant l’apprenant à effectuer un voyage dans son apprentissage langagier, personnel et culturel.

  2. Modeling Shocks Detected by Voyager 1 in the Local Interstellar Medium

    Science.gov (United States)

    Kim, T. K.; Pogorelov, N. V.; Burlaga, L. F.

    2017-07-01

    The magnetometer (MAG) on Voyager 1 (V1) has been sampling the interstellar magnetic field (ISMF) since 2012 August. The V1 MAG observations have shown draped ISMF in the very local interstellar medium disturbed occasionally by significant enhancements in magnetic field strength. Using a three-dimensional, data-driven, multi-fluid model, we investigated these magnetic field enhancements beyond the heliopause that are supposedly associated with solar transients. To introduce time-dependent effects at the inner boundary at 1 au, we used daily averages of the solar wind parameters from the OMNI data set. The model ISMF strength, direction, and proton number density are compared with V1 data beyond the heliopause. The model reproduced the large-scale fluctuations between 2012.652 and 2016.652, including major events around 2012.9 and 2014.6. The model also predicts shocks arriving at V1 around 2017.395 and 2019.502. Another model driven by OMNI data with interplanetary coronal mass ejections (ICMEs) removed at the inner boundary suggests that ICMEs may play a significant role in the propagation of shocks into the interstellar medium.

  3. Transition from the Unipolar Region to the Sector Zone: Voyager 2, 2013 and 2014

    Science.gov (United States)

    Burlaga, L. F.; Ness, N. F.; Richardson, J. D.

    2017-05-01

    We discuss magnetic field and plasma observations of the heliosheath made by Voyager 2 (V2) during 2013 and 2014 near solar maximum. A transition from a unipolar region to a sector zone was observed in the azimuthal angle λ between ˜2012.45 and 2013.82. The distribution of λ was strongly singly peaked at 270^\\circ in the unipolar region and double peaked in the sector zone. The δ-distribution was strongly peaked in the unipolar region and very broad in the sector zone. The distribution of daily averages of the magnetic field strength B was Gaussian in the unipolar region and lognormal in the sector zone. The correlation function of B was exponential with an e-folding time of ˜5 days in both regions. The distribution of hourly increments of B was a Tsallis distribution with nonextensivity parameter q = 1.7 ± 0.04 in the unipolar region and q = 1.44 ± 0.12 in the sector zone. The CR-B relationship qualitatively describes the 2013 observations, but not the 2014 observations. A 40 km s-1 increase in the bulk speed associated with an increase in B near 2013.5 might have been produced by the merging of streams. A “D sheet” (a broad depression in B containing a current sheet moved past V2 from days 320 to 345, 2013. The R- and N-components of the plasma velocity changed across the current sheet.

  4. Voyager 1 Observations of Galactic Cosmic Rays in the Local Interstellar Medium

    Science.gov (United States)

    Cummings, A. C.; Stone, E. C.; Heikkila, B. C.; Lal, N.; Webber, W. R.; Jóhannesson, G.; Moskalenko, I. V.; Orlando, E.; Porter, T. A.

    2017-01-01

    Voyager 1 crossed into the local interstellar medium in August 2012. The low-energy part of the energy spectra of Galactic cosmic rays (GCRs) was revealed for the first time, previously having been excluded from observation by the effects of solar modulation. We present the GCR energy spectra of most elements from H through Ni from 3 to a few hundred MeV nuc-1, and also of electrons from 2.7 to 74 MeV, for a period exceeding two years. We find that the H and He spectra have the same energy dependence between 3 and 346 MeV nuc-1, with a broad maximum in the10-50 MeV nuc-1 range and a H/He ratio of 12.2 +/- 0.9. The observed local interstellar gradient of 3-346 MeV H is - 0 . 009 +/- 0 . 055 %/AU. The energy spectrum of electrons (e- + e+) is consistent with E - 1 . 30 +/- 0 . 05. Propagation model fits to the observed spectra allow estimates of the energy density of GCRs and the ionization rates of atomic H, which will be presented and discussed. The propagation model fits also provide improved estimates of the elemental abundances in the source of Galactic cosmic rays. Work was supported by NASA grants NNN12AA01C, NNX13AC47G, NNX10AE78G, NNX16AF27G, and NNX15AU79G.

  5. PLASMA FLOWS AT VOYAGER 2 AWAY FROM THE MEASURED SUPRATHERMAL PRESSURES

    Energy Technology Data Exchange (ETDEWEB)

    McComas, D. J. [Southwest Research Institute, San Antonio, TX 78228 (United States); Schwadron, N. A., E-mail: dmccomas@swri.edu [University of New Hampshire, Durham, NH 03824 (United States)

    2014-11-01

    Plasma flows measured by Voyager 2 show a clear rotation away from radially outward with increasing penetration into the inner heliosheath while the overall flow speed remains roughly constant. However, the direction of rotation is far more into the transverse, and less into the polar direction, than predicted. No current model reproduces the key observational results of (1) the direction of flow rotation or (2) constancy of the flow speed. Here we show that the direction is consistent with flow away from the region of maximum pressure in the inner heliosheath, ∼20° south of the upwind direction, as measured by the Interstellar Boundary Explorer (IBEX). Further, we show that the dominance of the suprathermal ion pressure in the inner heliosheath measured by IBEX can explain both the observed flow rotation and constancy of the flow speed. These results indicate the critical importance of suprathermal ions in the physics of the inner heliosheath and have significant implications for understanding this key region of the heliosphere's interstellar interaction and astrophysical plasmas more broadly.

  6. Ecos literarios y memoria cartográfica del Famous Voyage de Francis Drake

    Directory of Open Access Journals (Sweden)

    García Redondo, José María

    2013-12-01

    Full Text Available Despite the English policy of secrecy, the news on Francis Drake’s circumnavigation travel was disseminated and fostered by foreign nations. In this article, we analyse the images of the corsair and his voyage across the Pacific in the Golden Age of Spanish Literature, as well as their representations in cartography, both for propaganda purposes and as an instrument of geographical knowledge production.Pese a quedar en secreto por la diplomacia inglesa, las noticias del viaje de circunnavegación de Francis Drake fueron difundidas y alimentadas por las naciones extranjeras. En este artículo analizamos las imágenes del corsario y de su paso por el océano Pacífico en la literatura española del Siglo de Oro, así como sus representaciones en la cartografía, como elemento de propaganda y de elaboración del conocimiento geográfico.

  7. Evidence for a distance (>8,700 R/sub j/) Jovian magnetotail: Voyager 2 observations

    Energy Technology Data Exchange (ETDEWEB)

    Lepping, R.P.; Burlaga, L.F.; Desch, M.D.; Klein, L.W.

    1982-08-01

    A correlative survey of Magnetometer (MAG) and Planetary Radio Astronomy (PRA) 1.2 kHz continuum radiation measurements from Voyager 2 provide evidence for at least eight distant Jovian magnetotail sightings occurring about once a month over the first 2/3 of 1981 at distances of approx.5,000 to approx.9,000 R/sub j/. The occurrences of these events are in good agreement with prior Plasma Wave Science and Plasma Science identifications. Observations of these distant magnetotail, or tail filament, encounters appear most prevalent in both MAG and PRA data sets when the spacecraft was closest to the Jupiter-Sun axis at approx. =6,500 R/sub j/ from the planet; the PRA events are also most intense during those times. A specific tail encounter occurring in mid-February 1981 is analyzed and shown to possess a remarkably symmetric structure in its central region. Tail bipolarity is characteristic of most of the eight events.

  8. Gravity Probe B Gyroscope Rotor

    Science.gov (United States)

    2003-01-01

    The Gravity Probe B (GP-B) is the relativity experiment developed at Stanford University to test two extraordinary predictions of Albert Einstein's general theory of relativity. The experiment will measure, very precisely, the expected tiny changes in the direction of the spin axes of four gyroscopes contained in an Earth-orbiting satellite at a 400-mile altitude. So free are the gyroscopes from disturbance that they will provide an almost perfect space-time reference system. They will measure how space and time are very slightly warped by the presence of the Earth, and, more profoundly, how the Earth's rotation very slightly drags space-time around with it. These effects, though small for the Earth, have far-reaching implications for the nature of matter and the structure of the Universe. This photograph is a close up of a niobium-coated gyroscope motor and its housing halves. GP-B is among the most thoroughly researched programs ever undertaken by NASA. This is the story of a scientific quest in which physicists and engineers have collaborated closely over many years. Inspired by their quest, they have invented a whole range of technologies that are already enlivening other branches of science and engineering. Launched April 20, 2004 , the GP-B program was managed for NASA by the Marshall Space Flight Center. Development of the GP-B is the responsibility of Stanford University along with major subcontractor Lockheed Martin Corporation. (Image credit to Don Harley.)

  9. Abundances of Jupiter's Trace Hydrocarbons from Voyager and Cassini. Data Tables: Cassini CIRS Observations Planetary and Space Science, Forthcoming 2010

    Science.gov (United States)

    Nixon, C. A.; Achterberg, R. K.; Romani, P. N.; Allen, M.; Zhang, X.; Teanby, N. A.; Irwin, P. G. J.; Flasar, F. M.

    2010-01-01

    The following six tables give the retrieved temperatures and volume mixing ratios of C2H2 and C2H6 and the formal errors on these results from the retrieval, as described in the manuscript. These are in the form of two-dimensional tables, specified on a latitudinal and vertical grid. The first column is the pressure in bar, and the second column gives the altitude in kilometers calculated from hydrostatic equilibrium, and applies to the equatorial profile only. The top row of the table specifies the planetographic latitude.

  10. Abundances of Jupiter's Trace Hydrocarbons from Voyager and Cassini. Data Tables: Cassini CIRS Observations Planetary and Space Science, Forthcoming 2010

    Science.gov (United States)

    Nixon, C. A.; Achterberg, R. K.; Romani, P. N.; Allen, M.; Zhang, X.; Teanby, N. A.; Irwin, P. G. J.; Flasar, F. M.

    2010-01-01

    The following six tables give the retrieved temperatures and volume mixing ratios of C2H2 and C2H6 and the formal errors on these results from the retrieval, as described in the manuscript. These are in the form of two-dimensional tables, specified on a latitudinal and vertical grid. The first column is the pressure in bar, and the second column gives the altitude in kilometers calculated from hydrostatic equilibrium, and applies to the equatorial profile only. The top row of the table specifies the planetographic latitude.

  11. Using data from automatic planetary stations for solving problems in astronomy and space physics

    Science.gov (United States)

    Stoeva, Penka; Stoev, Alexey; Bojurova, Eva

    The specific nature of the Astronomy and Space Physics problems promote students' interest in the relevant sciences and provoke their creativity. It is illustrated by numerous examples of positive response from the participants in the Astronomy Olympiad to extraordinary moments in problems, especially those related to space flight and scientific data and photographs from satellites and automatic interplanetary stations (AIS). Jupiter's satellite Io is one of the satellites with the highest volcano activity in the solar system. So far, the volcanoes of Io were photographed for a short time only by the interplanetary stations Voyager 1 and Galileo - sent by NASA, and New Horizons of ESA. By monitoring these often erupting volcanoes, however, one can quickly gather detailed information and establish methods for prediction of eruptions, including the Earth's volcanoes. This could push forward research on volcanism in the Solar system. Therefore, this issue was used for creation conditions for problems in astronomy. The report shows how through measurements on images of Io taken with AIS heights of the jets emitted by volcanoes are defined. Knowing the mass and radius of the satellite initial speed of the emitted particles is evaluated. Similarly, the initial rate of discharge of earth volcanoes and ice geysers on Saturn's satellite Enceladus are also evaluated. An attempt is made to explain the rings of ejection around the volcanoes on Io. The ratio of the diameter of the dispersion of the substance to the height of the stream is studied. Actually, maximum speed of the particles is evaluated as the boundaries of the volcanic "fountain" are determined by the fast moving particles reaching maximal height. The observed ratio is compared with the theoretical one derived by the students. The results show that although the volcanoes of Io , Earth's volcanoes and even ice geysers of Enceladus operate under very different conditions and arise from different causes, the initial

  12. TO GUIDE A PROBE TO THE MOON WITH LIGHT PRESSURE%借助光压将探测器推向月球

    Institute of Scientific and Technical Information of China (English)

    刘林

    2001-01-01

    若采用圆型限制性三体问题模型,从近地停泊轨道上发射一个月球探测器,其最小初始速度必须使相应的Jacobi常数C小于某一临界值C2.但这仅仅是探测器可能飞向月球的必要条件,而且这样飞向月球耗时过长.若采用Hohmann转移轨道,则需要获得较大的变轨冲量,能量消耗较大.如果需要仔细探测地月空间环境,而又不必很快地飞往月球,那么采用较大的太阳帆板,并使其法向有一特殊指向,可借助太阳光压加速引导探测器在不长的时间内飞往月球. 利用相应的分析和计算,证实上述考虑是有效的,而且若使太阳帆板截面积大到一定程度(如果技术上能实现),则无需任何动力,也可借助光压将探测器推向月球,就像一条太空帆船(简称太空帆).%In the dynamical model of the circular restricted three-body problem and for launching a lunar probe from parking orbit, the minimum initial velocity should satisfy the condition that the Jacobian constant C is smaller than C2 (in the Earth-Moon system, C2=3. 20034491). Then the probe may be accelerated to a speed of Vv > 10. 8746 km/s at perigee (some 200 km high). However, this is only the necessary condition for the probe to fly to the moon and the voyage time is too long. If a Hohmann transfer orbit is adopted, a more impulse for the orbit transfer will be required, and in a sense more power will be consumed. If it is needed to carefully explore the environment of the Eath-Moon space and not to fly to the moon so quickly, then to the base of the above minimum velocity the probe can be guided faster to the moon with light pressure. For this reason, a large solar energy sail with a special normal needs to be installed on the probe. In this way, the purpose of exploring the Earth-Moon space can be attained and the flight will not spend a very long time.   The results of computations show that the above-stated plan is

  13. Spaceborne Double-probe Electric Field Sensor for Space Electromagnetic Environment Monitoring%空间电磁环境监测用双探针式星载电场探测仪

    Institute of Scientific and Technical Information of China (English)

    任仁; 陈贤祥; 夏善红; 吕元生

    2012-01-01

    针对空间电磁环境监测需求,该文介绍了双探针式在轨电场探测方法.概述了双探针式、天线式和电子漂移式3种检测方法的异同,重点探讨了双探针式电场测量方法的原理、系统组成及测试标定方法.设计实现了敏感探头和数据采集处理单元,通过阻容耦合方式模拟电场仪在轨工作环境对系统进行了测试.测试结果显示SLF,VLF和HF频段的噪声本底分别小于4μVm-1Hz-1/2,1μVm-1Hz-1/2和0.5μVm-1Hz-1/2.%This paper presents a method of double-probe electric field in-orbit detection. Differences of three kinds of instrument including double-probe type, antenna type and electron drift type are briefly introduced. The principle, architecture and calibration method of double-probe spaceborne electric field sensor are described in detail. Sensitive probe and signal acquisition & processing units are implemented and tested with sensor in-orbit environment simulation through resistive coupling. Experiment results indicate that noise amplitude spectrum intensity of band SLF, VLF, HF are less than 4 μVm-1Hz-1/2, 1 μVm-1Hz-1/2 , 0.5 μVm-1Hz-11/2 separately.

  14. Phoenix Conductivity Probe with Shadow and Toothmark

    Science.gov (United States)

    2008-01-01

    NASA's Phoenix Mars Lander inserted the four needles of its thermal and conductivity probe into Martian soil during the 98th Martian day, or sol, of the mission and left it in place until Sol 99 (Sept. 4, 2008). The Robotic Arm Camera on Phoenix took this image on the morning of Sol 99 after the probe was lifted away from the soil. The imprint left by the insertion is visible below the probe, and a shadow showing the probe's four needles is cast on a rock to the left. The thermal and conductivity probe measures how fast heat and electricity move from one needle to an adjacent one through the soil or air between the needles. Conductivity readings can be indicators about water vapor, water ice and liquid water. The probe is part of Phoenix's Microscopy, Electrochemistry and Conductivity suite of instruments. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  15. Isotropic Broadband E-Field Probe

    Directory of Open Access Journals (Sweden)

    Béla Szentpáli

    2008-01-01

    Full Text Available An E-field probe has been developed for EMC immunity tests performed in closed space. The leads are flexible resistive transmission lines. Their influence on the field distribution is negligible. The probe has an isotropic reception from 100 MHz to 18 GHz; the sensitivity is in the 3 V/m–10 V/m range. The device is an accessory of the EMC test chamber. The readout of the field magnitude is carried out by personal computer, which fulfils also the required corrections of the raw data.

  16. Loops in Twistor Space

    CERN Document Server

    Bena, I; Kosower, D A; Roiban, R; Bena, Iosif; Bern, Zvi; Kosower, David A.; Roiban, Radu

    2004-01-01

    We elucidate the one-loop twistor-space structure corresponding to momentum-space MHV diagrams. We also discuss the infrared divergences, and argue that only a limited set of MHV diagrams contain them. We show how to introduce a twistor-space regulator corresponding to dimensional regularization for the infrared-divergent diagrams. We also evaluate explicitly the `holomorphic anomaly' pointed out by Cachazo, Svrcek, and Witten, and use the result to define modified differential operators which can be used to probe the twistor-space structure of one-loop amplitudes.

  17. An Ultrasonographic Periodontal Probe

    Science.gov (United States)

    Bertoncini, C. A.; Hinders, M. K.

    2010-02-01

    Periodontal disease, commonly known as gum disease, affects millions of people. The current method of detecting periodontal pocket depth is painful, invasive, and inaccurate. As an alternative to manual probing, an ultrasonographic periodontal probe is being developed to use ultrasound echo waveforms to measure periodontal pocket depth, which is the main measure of periodontal disease. Wavelet transforms and pattern classification techniques are implemented in artificial intelligence routines that can automatically detect pocket depth. The main pattern classification technique used here, called a binary classification algorithm, compares test objects with only two possible pocket depth measurements at a time and relies on dimensionality reduction for the final determination. This method correctly identifies up to 90% of the ultrasonographic probe measurements within the manual probe's tolerance.

  18. Hard probes 2006 Asilomar

    CERN Multimedia

    2006-01-01

    "The second international conference on hard and electromagnetic probes of high-energy nuclear collisions was held June 9 to 16, 2006 at the Asilomar Conference grounds in Pacific Grove, California" (photo and 1/2 page)

  19. Selectable polarization at X-band. [Deep Space Network modifications

    Science.gov (United States)

    Hartop, R. W.

    1977-01-01

    The X-band feeds in the Deep Space Network were upgraded to include selectable polarization in time for the Voyager missions to the outer planets. The modified antenna feed has the following major items added: two circular waveguide rotary joints, drive motor and gear reducer, gear assembly, two microswitches, and a polarization control junction box. The overall length of the feed remains the same because circular waveguide spacing sections were designed into the original feed to readily permit such modifications. There is no significant increase in antenna noise temperature compared to the original feed.

  20. Direct measurement of surface-state conductance by microscopic four-point probe method

    DEFF Research Database (Denmark)

    Hasegawa, S.; Shiraki, I.; Tanikawa, T.

    2002-01-01

    For in situ measurements of local electrical conductivity of well defined crystal surfaces in ultrahigh vacuum, we have developed microscopic four-point probes with a probe spacing of several micrometres, installed in a scanning-electron - microscope/electron-diffraction chamber. The probe...

  1. Surface-sensitive conductivity measurement using a micro multi-point probe approach

    DEFF Research Database (Denmark)

    Perkins, Edward; Barreto, Lucas; Wells, Justin

    2013-01-01

    An instrument for microscale electrical transport measurements in ultra-high vacuum is presented. The setup is constructed around collinear lithographically-created multi-point probes with a contact spacing down to 500 nm. Most commonly, twelve-point probes are used. These probes are approached t...... for epitaxial graphene on SiC and degenerately doped Bi2Se3....

  2. Prevention of Renal Stone Complications in Space Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — AIM 1. Refine ultrasound probes to detect, reposition, and fragment kidney stones. Task 1.1. Select imaging probe for stone repositioning. Clinical trials are...

  3. Explaining the 11-year periodicity in Neptune's atmosphere with Voyager 2 data

    Science.gov (United States)

    Aplin, Karen; Harrison, R. Giles

    2017-04-01

    Long-duration observations of Neptune's brightness at two visible wavelengths, made since the 1970s by Lockwood and co-workers [e.g. 1], give a disk-averaged estimate of variations in the planet's clouds and atmospheric aerosol. Brightness variations have previously been associated with the 11-year solar cycle [1], through two solar-modulated mechanisms, firstly, ultraviolet-related colour changes [2], or galactic cosmic ray (GCR)-related nucleation effects on atmospheric particle formation. Over 40 years of brightness data (1972-2014) are used here to show, with physically realistic modelling, that ultraviolet and GCR are likely to be modulating Neptune's atmosphere in combination rather than as alternatives. Existence of the cosmic ray mechanism is further supported by the response of Neptune's atmosphere to an intermittent 1.5- to 1.9-year periodicity during the mid-1980s. This occurred in GCR and, critically for its use in mechanism discrimination, not the solar ultraviolet. This periodicity was detected both at Earth, and in GCR measured by Voyager 2, which was close to Neptune at that time. The similar coincident variability in Neptune's brightness suggests nucleation onto GCR ions. Both GCR and ultraviolet particle modulation mechanisms are expected to occur more rapidly than the subsequent atmospheric transport processes.[2] [1] Lockwood, G. W. & Thompson, D. T. Photometric variability of Neptune, 1972-2000. Icarus 156, 37-51 (2002). [2] Aplin, K. L. & Harrison, R. G. Determining solar effects in Neptune's atmosphere. Nat. Commun. 7:11976 doi: 10.1038/ncomms11976 (2016)

  4. THE GLOBAL CONFIGURATION OF THE HELIOSHEATH INFERRED FROM RECENT VOYAGER 1 OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, L. A.; Gloeckler, G., E-mail: lafisk@umich.edu [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143 (United States)

    2013-10-20

    Recent observations from Voyager 1 in the nose region of the heliosheath, an area created by the motion of the Sun through the local interstellar medium, have revealed that: (1) beyond ∼113 AU from the Sun, the anisotropy of low-energy ions becomes very small in all directions, which has been interpreted as indicating that the solar wind flow speed has decreased to near zero; (2) at ∼120 AU, anomalous cosmic rays (ACRs) are accelerated to their highest energies; and (3) at ∼122 AU, there is a precipitous decrease both in ACRs and in termination shock particles (TSPs) that are convected downstream from the termination shock. In this paper, the low-energy anisotropy observations are interpreted as implying, not that the solar wind flow speed has decreased to near zero, but rather that the solar wind flow is closely aligned with the magnetic field direction, which is observed to be in the azimuthal direction. A simple model for the heliosheath is then constructed, based on the anisotropy observations and the observational evidence that the dominant pressure is contained in pickup ions, TSPs, and ACRs. The model predicts that there are jets of supersonic and super-Alfvénic solar wind flowing along the flanks of the heliosheath, stretching and opening the heliosheath magnetic field into the interstellar medium. TSPs and ACRs that are accelerated in the nose region can easily escape along the magnetic field in the open region of the heliosheath, resulting in the precipitous decrease in the intensity of TSPs and ACRs.

  5. Transient Cosmic-ray Events beyond the Heliopause: Interpreting Voyager-1 Observations

    Science.gov (United States)

    Kóta, J.; Jokipii, J. R.

    2017-04-01

    In 2013 March and 2014 May, Voyager-1 (V1) experienced small but significant increases in the flux of galactic cosmic rays (GCRs) in the hundred MeV/n range. Additionally, V1 also saw episodic depletion of GCR flux around perpendicular pitch angles. We discuss the pitch-angle distribution and the time profiles of these events. In a previous paper, we interpreted the 2013 “bump” as the GCRs remotely sensing a shock that reached the magnetic field line passing through V1: particles gained energy as they were reflected on the approaching region of the stronger magnetic field of the disturbance. Here, we point out that energy gain is not restricted to reflected particles—GCRs passing through the disturbance also gain energy. The effect should be present in a broad range of pitch angles with the maximum increase of GCR intensity predicted to occur at the critical reflection angle. In this paper, the shock is not step-like, but a gradual increase of the magnetic field strength, B, taking a few days, in agreement with V1 measurements. This smoothens the profile of the predicted bump in the GCR flux. We also address the linear episodic decreases seen around perpendicular pitch angles. These events are interpreted in terms of adiabatic cooling behind the shock due to the slow weakening of B. We present simple numerical model calculations and find that a gradual shock followed by a slow decrease of B, as observed, may account for both the episodic increases and the anisotropic depletion of GCR fluxes.

  6. Analysis of Voyager Observed High-Energy Electron Fluxes in the Heliosheath Using MHD Simulations

    Science.gov (United States)

    Washimi, Haruichi; Webber, W. R.; Zank, Gary P.; Hu, Qiang; Florinski, Vladimir; Adams, James; Kubo, Yuki

    2011-01-01

    The Voyager spacecraft (V1 and V2) observed electrons of 6-14 MeV in the heliosheath which showed several incidences of flux variation relative to a background of gradually increasing flux with distance from the Sun. The increasing flux of background electrons is thought to result from inward radial diffusion. We compare the temporal electron flux variation with dynamical phenomena in the heliosheath that are obtained from our MHD simulations. Because our simulation is based on V2 observed plasma data before V2 crossed the termination shock, this analysis is effective up to late 2008, i.e., about a year after the V2-crossing, during which disturbances, driven prior to the crossing time, survived in the heliosheath. Several electron flux variations correspond to times directly associated with interplanetary shock events. One noteworthy example corresponds to various times associated with the March 2006 interplanetary shock, these being the collision with the termination shock, the passage past the V1 spacecraft, and the collision with the region near the heliopause, as identified by W.R. Webber et al. for proton/helium of 7-200 MeV. Our simulations indicate that all other electron flux variations, except one, correspond well to the times when a shock-driven magneto-sonic pulse and its reflection in the heliosheath either passed across V1/V2, or collided with the termination shock or with the plasma sheet near the heliopause. This result suggests that variation in the electron flux should be due to either direct or indirect effects of magnetosonic pulses in the heliosheath driven by interplanetary shocks

  7. Voyager 1 observations of the interstellar magnetic field and the transition from the heliosheath

    Energy Technology Data Exchange (ETDEWEB)

    Burlaga, L. F. [NASA Goddard Space Flight Center, Code 673, Greenbelt, MD 20771 (United States); Ness, N. F., E-mail: lburlagahsp@verizon.net, E-mail: nfnudel@yahoo.com [Institute for Astrophysics and Computational Sciences, Catholic University of America, Washington, DC 20064 (United States)

    2014-04-01

    Voyager 1 (V1) has been observing interstellar magnetic fields for more than one year beginning ≈2012/209, when V1 crossed a current sheet, a 'CS0' having the structure of a tangential discontinuity. The inclination of this current sheet is consistent with an interstellar magnetic field B draped on a blunt heliopause. Two other current sheets (sector boundaries) were observed at ≈2012/167 and ≈2011/276 with high inclinations (99° ± 10° and 89° ± 10°, respectively). From 2013.0 to ≈2013.6, the difference between the azimuthal angle λ of B from the Parker spiral angle at the latitude 34.°6 of V1 was λ – λ{sub P} = 22° ± 3° and the corresponding difference of the elevation angle δ was δ – δ{sub P} = 23° ± 8°. During 2012, the deviation from the Parker spiral angle was somewhat smaller. The interstellar magnetic field has a 'west to east polarity,' opposite to the direction of planetary motions. The magnitude of B varied smoothly in the range 0.38-0.59 nT with an average B = 0.486 ± 0.045 after 2012/237.7. The transition from heliosheath to interstellar magnetic fields is related to a 'two-step' increase in the cosmic ray intensity observed by V1 from ≈2012.30 to ≈2012.65. The first step increase began near the end of an unusual 'away-polarity' sector, and it reached a plateau when V1 moved into a 'toward-polarity' sector that ended at CS0. The second step increase began slowly after V1 crossed CS0, and it ended abruptly at 2012/237.728.

  8. The bubble-like shape of the heliosphere observed by Voyager and Cassini

    Science.gov (United States)

    Dialynas, K.; Krimigis, S. M.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

    2017-04-01

    For more than five decades, the shape and interactions of the heliosphere with the local interstellar medium have been discussed in the context of two competing models, posited in 1961 1 : a magnetosphere-like heliotail and a more symmetric bubble shape. Although past models broadly assumed the magnetosphere-like concept, the accurate heliospheric configuration remained largely undetermined due to lack of measurements. In recent years, however, Voyagers 1 and 2 (V1 and V2) crossed the termination shock — the boundary where the solar wind drops — north and south of the ecliptic plane at 94 au 2,3 and 84 au 4 in 2004 and 2007, respectively, and discovered the reservoir of ions and electrons that constitute the heliosheath, while Cassini remotely imaged the heliosphere 5 for the first time in 2003. Here we report 5.2-55 keV energetic neutral atom (ENA) global images of the heliosphere obtained with the Cassini/Ion and Neutral Camera (INCA). We compare them with 28-53 keV ions measured within the heliosheath by the low-energy charged particle (LECP) experiment onboard V1 and V2 over an 11-year period (2003-2014). We show that the heliosheath ions are the source of ENA. These observations also demonstrate that the heliosphere responds promptly, within ~2-3 years, to outward propagating solar wind changes in both the nose and tail directions. These results, together with the V1 measurement of a ~0.5 nT interstellar magnetic field 6 and the enhanced ratio between particle pressure and magnetic pressure in the heliosheath 7 , strongly suggest a diamagnetic bubble-like heliosphere with few substantial tail-like features. Our results are consistent with recent modelling 8-11 .

  9. Schultze Gets The Blues : le voyage comme quête identitaire

    Directory of Open Access Journals (Sweden)

    Markus Raith

    2010-11-01

    Full Text Available Schultze Gets The Blues porte sur les rapports entre musique, langue et identité. Dans la tradition du Bildungsroman allemand, le film raconte un voyage initiatique, entre l’Allemagne et les États-Unis, entre la polka allemande et le blues américain, qui remet en question l’identité du personnage principal. Mais Schultze Gets The Blues peut être aussi considéré comme une réécriture filmique de l’errance chère aux romantiques allemands sous le signe du road movie. L’histoire de Schultze, un mineur de sel est-allemand qui joue de l’accordéon traditionnel allemand pendant son temps libre, est celle d’un passeur de frontières et de cultures, qui glisse d’un univers à l’autre, géographiquement marqué par l’Allemagne et l’Amérique, musicalement par la Polka et le Blues et linguistiquement par l’allemand et l’anglais. Sous forme de quête identitaire à travers langue, culture et musique, le film raconte la découverte de l’Autre qui permet de reconstruire sa propre identité. Nous nous proposons de retracer ce processus de reconstruction identitaire par l’expérience de l’altérité, tout en analysant l’imaginaire et l’intertexte mythologique et littéraire qu’exploite le film.

  10. Neuronal plasticity: adaptation and readaptation to the environment of space

    Science.gov (United States)

    Correia, M. J.

    1998-01-01

    While there have been few documented permanent neurological changes resulting from space travel, there is a growing literature which suggests that neural plasticity sometimes occurs within peripheral and central vestibular pathways during and following spaceflight. This plasticity probably has adaptive value within the context of the space environment, but it can be maladaptive upon return to the terrestrial environment. Fortunately, the maladaptive responses resulting from neuronal plasticity diminish following return to earth. However, the literature suggests that the longer the space travel, the more difficult the readaptation. With the possibility of extended space voyages and extended stays on board the international space station, it seems worthwhile to review examples of plastic vestibular responses and changes in the underlying neural substrates. Studies and facilities needed for space station investigation of plastic changes in the neural substrates are suggested. Copyright 1998 Elsevier Science B.V.

  11. Information Gains from Cosmological Probes

    CERN Document Server

    Grandis, S; Refregier, A; Amara, A; Nicola, A

    2015-01-01

    In light of the growing number of cosmological observations, it is important to develop versatile tools to quantify the constraining power and consistency of cosmological probes. Originally motivated from information theory, we use the relative entropy to compute the information gained by Bayesian updates in units of bits. This measure quantifies both the improvement in precision and the 'surprise', i.e. the tension arising from shifts in central values. Our starting point is a WMAP9 prior which we update with observations of the distance ladder, supernovae (SNe), baryon acoustic oscillations (BAO), and weak lensing as well as the 2015 Planck release. We consider the parameters of the flat $\\Lambda$CDM concordance model and some of its extensions which include curvature and Dark Energy equation of state parameter $w$. We find that, relative to WMAP9 and within these model spaces, the probes that have provided the greatest gains are Planck (10 bits), followed by BAO surveys (5.1 bits) and SNe experiments (3.1 ...

  12. Observations of Low-Frequency Magnetic Waves due to Newborn Interstellar Pickup Ions Using ACE, Ulysses, and Voyager Data

    Science.gov (United States)

    Smith, Charles W.; Aggarwal, Poornima; Argall, Matthew R.; Burlaga, Leonard F.; Bzowski, Maciej; Cannon, Bradford E.; Gary, S. Peter; Fisher, Meghan K.; Gilbert, Jason A.; Hollick, Sophia J.; Isenberg, Philip A.; Joyce, Colin J.; Murphy, Neil; Nuno, Raquel G.; Pine, Zackary B.; Richardson, John D.; Schwadron, Nathan A.; Skoug, Ruth M.; Sokół, Justyna M.; Taylor, David K.; Vasquez, Bernard J.

    2017-09-01

    Wave excitation by newborn interstellar pickup ions (PUIs) plays a significant role in theories that attempt to describe IBEX and Voyager observations in the solar wind and heliosheath. The same dynamic processes can be far-reaching and extend into the inner heliosphere to at least 1AU and likely to smaller heliocentric distances. While the high-resolution magnetic field measurements required to study these waves are not yet available in the heliosheath, we have studied a range of available observations and found evidence of waves due to interstellar PUIs using ACE (1998–2015 at 1 AU), Ulysses (1996–2006 at 2 to 5 AU, high and low latitudes) and Voyager (1978–1979 and 2 to 6 AU) observations. Efforts to extend the Voyager observations to 35 AU are ongoing. We have examined these data sets and report on observations of low-frequency waves that result from newborn interstellar pickup H+ and He+ ions. Although not as common as theory originally predicted, we presently have identified 524 independent occurrences. Our conclusion from studying these waves is that they are seen only when the ambient turbulence is sufficiently weak. The instability that generates these waves requires a slow accumulation of wave energy over several to tens of hours to achieve observable wave amplitudes. In regions where the turbulence is moderate to strong, the turbulence absorbs the wave energy before it can reach observable levels and transports the energy to the dissipation scales where it heats the background thermal particles. Only intervals with the weakest turbulence will permit energy accumulation over this time scale. These conditions are most often, but not exclusively, achieved in solar wind rarefaction regions.

  13. Dual active surface heat flux gage probe

    Science.gov (United States)

    Liebert, Curt H.; Kolodziej, Paul

    1995-02-01

    A unique plug-type heat flux gage probe was tested in the NASA Ames Research Center 2x9 turbulent flow duct facility. The probe was fabricated by welding a miniature dual active surface heat flux gage body to the end of a hollow metal cylindrical bolt containing a metal inner tube. Cooling air flows through the inner tube, impinges onto the back of the gage body and then flows out through the annulus formed between the inner tube and the hollow bolt wall. Heat flux was generated in the duct facility with a Huels arc heater. The duct had a rectangular cross section and one wall was fabricated from 2.54 centimeter thick thermal insulation rigid surface material mounted onto an aluminum plate. To measure heat flux, the probe was inserted through the plate and insulating materials with the from of the gage located flush with the hot gas-side insulation surface. Absorbed heat fluxes measured with the probe were compared with absorbed heat fluxes measured with six water-cooled reference calorimeters. These calorimeters were located in a water-cooled metal duct wall which was located across from the probe position. Correspondence of transient and steady heat fluxes measured with the reference calorimeters and heat flux gage probe was generally within a satisfactory plus or minus 10 percent. This good correspondence was achieved even though the much cooler probe caused a large surface temperature disruption of 1000K between the metal gage and the insulation. However, this temperature disruption did not seriously effect the accuracy of the heat flux measurement. A current application for dual active surface heat flux gages is for transient and steady absorbed heat flux, surface temperature and heat transfer coefficient measurements on the surface of an oxidizer turbine inlet deflector operating in a space shuttle test bed engine.

  14. Holographic backgrounds from D-brane probes

    CERN Document Server

    Moskovic, Micha

    2014-01-01

    This thesis focuses on the derivation of holographic backgrounds from the field theory side, without using any supergravity equations of motion. Instead, we rely on the addition of probe D-branes to the stack of D-branes generating the background. From the field theory description of the probe branes, one can compute an effective action for the probes (in a suitable low-energy/near-horizon limit) by integrating out the background branes. Comparing this action with the generic probe D-brane action then allows to determine the holographic background dual to the considered field theory vacuum. In the first part, the required pre-requisites of field and string theory are recalled and this strategy to derive holographic backgrounds is explained in more detail on the basic case of D3-branes in flat space probed by a small number of D-instantons. The second part contains our original results, which have already appeared in arXiv:1301.3738, arXiv:1301.7062 and arXiv:1312.0621. We first derive the duals to three conti...

  15. Particle sizes of the Uranus delta ring's inner diffuse companion through comparison of RSS and PPS Voyager occultation data

    Science.gov (United States)

    Hui, John; Horn, Linda J.; Lane, Arthur L.

    1991-01-01

    In January, 1976, Voyager 2's photopolarimeter and UV spectrometer observed Delta Sagitarii and Beta Persei during their occultation by the Uranian delta ring. An inner diffuse companion of this ring was detected and found to have an average width of 12 km. By comparing the widths and equivalent depths of the two sets of data, it is established that the particles making the greatest contribution to the integrated opacities of the companion are of greater-than-several-cm sizes. The particles appear to be located away from the photopolarimetry edges, where there may be particles smaller than those observed elsewhere.

  16. Stéphane Hugon, Circumnavigations : l’imaginaire du voyage dans l’expérience Internet

    Directory of Open Access Journals (Sweden)

    Mathieu O’Neil

    2012-03-01

    Full Text Available In Circumnavigations. L’imaginaire du voyage dans l’expérience Internet Stéphane Hugon proposes a sociology of practices and imaginings to uncover the workings of the online experience. The book was written under the auspices of Michel Maffesoli (who contributes an introduction and emphasises Maffesolian tropes such as the way micro-events act as social glue, the importance of “consensus” understood as the sharing of feelings and sensitivities, and the return in a new guise of tribal forms. ...

  17. A vueltas con la traducción española de /Nouveau voyage en Espagne/ de Peyron

    Directory of Open Access Journals (Sweden)

    Irene Aguilá Solana

    2009-04-01

    Full Text Available This study compares Nouveau Voyage en Espagne (1780 written by Peyron with the translation from French into Spanish by José García Mercadal published in 1952.The differences noticed between both texts revolve around two main points: modifications and errors. The first point includes the changes in the textual disposition, as well as the omissions, additions and corrections that the translator makes upon the original. The second point considers the various reasons of unfortunate translation of Peyron’s text. Among those reasons,literal translation, misinterpretation of graphemes or sounds, and typing mistakes,can be found.

  18. Nocturne: "Rencontres du troisième type" : un voyage dans l'espace-temps entre musique et danse

    OpenAIRE

    Burkhalter, Isabelle

    2015-01-01

    Tiré du site internet du blog des Musées d'art et d'histoire (http://blog.mahgeneve.ch): "C'est une nocturne exceptionnelle qui attend au Musée d'art et d'histoire les curieux, les mélomanes, les ouailles de Terpsichore, ou autres amateurs d'expériences inédites. La musique, la danse, l'espace et le temps se mêleront pour nous faire voyager dans des sphères extraterrestres.".

  19. To Pergamon and back. An account of a Homeric voyage, with observations on the beliefs and practices of fellow travellers and natives

    Science.gov (United States)

    Shaw, Denis M.

    1988-12-01

    Many undertake the journey to Pergamon, and live to tell their grandchildren of privations suffered, hardships overcome, brigands repelled and the like. Few comment on the reasons why they chose to make the voyage, what investment was made to ensure the seaworthiness of the vessel, what time was spent in detached reflection to guarantee the quality of the goods carried, what outcome in spiritual fortification was hoped for, what gifts were prepared for the benefit (in fruitful intercourse) of other voyagers, natives, and sailors. Using the premise that (with apologies to Plato) "the unexamined voyage is not worth taking", some cheerful discourse is offered for past and future travellers. In accord with one of the few truths in science, namely that "all meeting abstracts are bad abstracts", the reader is left to muse on what really was presented.

  20. Interview of Edward C. Stone, Caltech and NASA Voyager project scientist on the occasion of the Spaceparts conference at CERN, on the 100th anniversary of the cosmic rays discovery

    CERN Multimedia

    CERN Visual Media Office

    2012-01-01

    Interview of Edward C. Stone, Caltech and NASA Voyager project scientist on the occasion of the Spaceparts conference at CERN, on the 100th anniversary of the cosmic rays discovery. He describes the Voyager mission since launch in 1977 to current position at the frontier of the solar system.

  1. Probing space charge effect on electroluminescence of indium tin oxide (ITO)/N,N′-di-[(1-naphthyl)-N,N′-diphenyl]-(1,1′-biphenyl)-4, 4′-diamine (α-NPD)/tris(8-hydroxy-quinolinato) aluminum (III) (Alq{sub 3})/Al diodes by time-resolved electric-field-induced optical second-harmonic generation measurement

    Energy Technology Data Exchange (ETDEWEB)

    Sadakata, Atsuo; Osada, Kenshiro; Taguchi, Dai; Manaka, Takaaki; Iwamoto, Mitsumasa, E-mail: iwamoto@pe.titech.ac.jp

    2014-03-03

    By using time-resolved electric-field-induced optical second-harmonic generation measurement, we studied the electroluminescence (EL) mechanism which is activated in double-layer organic light-emitting diodes (indium tin oxide/N,N′-di-[(1-naphthyl)-N,N′-diphenyl]-(1,1′-biphenyl)-4,4′-diamine (α-NPD)/tris(8-hydroxy-quinolinato) aluminum (III) (Alq{sub 3})/Al) in the high frequency region with application of AC square voltages at various duty-ratios. Results showed that holes were accumulated at the α-NPD/Alq{sub 3} interface in proportion to the duty-ratio, and corresponded well to the increasing EL enhancement at the high frequency. Our previous proposed model on the EL enhancement assisted by electron injection from the Al electrode in the presence of the space charge field was well confirmed. - Highlights: • We studied space charge (SC) effects in double-layer organic light emitting diodes. • The second-harmonic generation measurement was used to directly probe the SC field. • Space charge fields due to interfacial accumulated charge were verified. • We showed that SC electric fields contribute to electroluminescence emissions.

  2. Collective electronic effects in scanning probe microscopy

    Science.gov (United States)

    Passian, Ali

    The surface plasmon dispersion relations are calculated for a metal coated dielectric probe above a dielectric half space with and without metal coating. Employing prolate spheroidal coordinate system this configuration was modeled as confocal single-sheeted hyperboloids of revolution superimposed on planar domains. The involved media are characterized by frequency dependent, spatially local dielectric functions. Due to subwavelength dimensions of the region of interest, nonretarded electrodynamics is utilized to derive exact analytical expressions describing the resonant surface modes. The dispersion relations are studied as functions of the parameter that defines the hyperboloidal boundaries of the tip and the corresponding coating, and as functions of the involved coating thicknesses. Both parallel and perpendicular polarizations are considered. The results are simulated numerically and limiting cases are discussed with comparison to the Cartesian thin foil case. Using this new type of probe-substrate configuration, the surface plasmon coupling mechanism is investigated experimentally utilizing a scanning probe microscope, and the signal strength acquired by the probe is measured as a function of the distance between the probe and the sample. This is repeated at three different wavelengths of the incident p-polarized photons used to stimulate surface plasmons in the thin metal foil. The results are compared with the theory. Utilizing the prolate spheroidal coordinate system, the related and relevant problem of the Coulomb interaction of a dielectric probe tip with a uniform field existing above a semiinfinite, homogeneous dielectric substrate was studied. This is of interest in atomic force microscopy when the sample surface is electrically charged. The induced polarization surface charge density and the field distribution at the bounding surface of the dielectric medium with the geometry of a single-sheeted hyperboloid of revolution located above the dielectric

  3. High Frontier: The Journal for Space and Missile Professionals. Volume 7, Number 4, August 2011

    Science.gov (United States)

    2011-08-01

    galvanized President Dwight D. Eisenhower and the Congress to give the US the ability to operate in and from space. On the civilian side, these...August 1958, after concluding the first ever submerged voyage under the North Pole ). U S N av y High Frontier 24 Initial Criteria and Screening...causing the project to revert to the heavier stainless steel gear system with wet lubricant used by prior projects. To keep the lubricant from

  4. The presentation of the results of Alexander von Humboldt's voyage to Carlos IV

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Puig-Samper

    2016-05-01

    Full Text Available Resumen  Desde nuestras primeras investigaciones sobre la estancia de Alexander von Humboldt en España siempre nos sorprendió la ausencia de una mínima relación posterior del sabio prusiano con la corona española y sus autoridades. Iniciada una nueva investigación, encontramos que efectivamente se produjo el envío de un primer trabajo a Carlos IV desde Roma acompañado de una carta de gratitud por la protección recibida durante su viaje americano y de sumisión a la corona española, que ahora presentamos.   Summary Ever since our first research into Alexander von Humboldt's stay in Spain, the absence of an ensuing relationship between the wise Prussian and the Spanish Crown and Authorities had always surprised us. On starting new research, we found that indeed he sent his first work to Carlos IV from Rome accompanied by a letter of gratitude for the protection he had received during his American trip and submission to the Spanish Crown, which we now present. This first literary fruit of his voyage, which Alexander von Humboldt alluded to in the letter is the first instalment of his work Plantes Équinoxiales, Recueillies au Mexique, dans l’ile de Cuba, dans les provinces de Caracas, de Cumana etc., published in Paris in 1805.   Zusammenfassung Seit unseren ersten Forschungen über den Aufenthalt Alexander von Humboldts in Spanien hat uns das Fehlen einer hieran anschließenden Beziehung des preußischen Wissenschaftlers mit der spanischen Krone und ihren Behörden erstaunt. Im Laufe einer erneuten Aufnahme der Forschung, haben wir nun entdeckt, dass Humboldt in der Tat von Rom aus eine erste Arbeit an Karl IV gesandt hatte, zusammen mit einem Schreiben des Dankes (für den während der amerikanischen Reise erhaltenen Schutz sowie seiner Unterordnung unter die spanische Krone, das wir nun präsentieren. Das erste literarische Ergebnis seiner Reise, auf das Humboldt in diesem Brief verweist, ist der erste Faszikel seines Werkes

  5. Les voyages organisés par ordre du roi à Versailles

    Directory of Open Access Journals (Sweden)

    Jan Vandersmissen

    2011-09-01

    Full Text Available Cette conférence étudiera les voyages financés par l’État français aux xviie et xviiie siècles en vue d’une acquisition de nouvelles connaissances sur le monde en dehors de l’Europe. Cette période fut témoin d’un changement radical de l’exploration scientifique outre-mer. Pendant le règne du Roi-Soleil, et sous l’impulsion de Colbert, les voyageurs académiques partant de la France, ainsi que certains Français résidant dans les territoires d’outre-mer, recevaient des instructions pour mieux orienter leurs observations et améliorer la collecte de données, et ceci afin de recueillir des connaissances qui seraient utiles à l’État. Les projets à petite échelle prévalaient. Grâce au soutien d’institutions royales comme l’Académie royale des sciences ou le Jardin du roi, des individus comme Charles Plumier, Joseph Pitton de Tournefort et Louis Éconches Feuillée ramenaient des échantillons et descriptions de « plantes utiles ». D’autres, comme Jean Richer, faisaient des observations astronomiques dans l’hémisphère Sud, améliorant ainsi non seulement la connaissance géographique, mais aussi les techniques cartographiques et les compétences dans le domaine de la navigation. Sous Louis XV vint une amplification des entreprises. La rivalité avec l’Angleterre conduisait les Français vers le Pacifique. Science, exploration et géopolitique se confondaient. De vastes équipes de chercheurs montaient à bord de navires militaires. Les expéditions enrichirent les collections scientifiques de Versailles et des institutions royales à Paris. Sous Louis XVI, ce processus culmina dans l’expédition de La Pérouse. Trois aspects de la politique scientifique française dans le domaine de l’exploration seront analysés ici en détail : les mécanismes de patronage et de protection, les mécanismes d’approbation scientifique et la mise à profit des connaissances rassemblées par les voyageurs.

  6. Spacecraft Health Automated Reasoning Prototype (SHARP): The fiscal year 1989 SHARP portability evaluations task for NASA Solar System Exploration Division's Voyager project

    Science.gov (United States)

    Atkinson, David J.; Doyle, Richard J.; James, Mark L.; Kaufman, Tim; Martin, R. Gaius

    1990-01-01

    A Spacecraft Health Automated Reasoning Prototype (SHARP) portability study is presented. Some specific progress is described on the portability studies, plans for technology transfer, and potential applications of SHARP and related artificial intelligence technology to telescience operations. The application of SHARP to Voyager telecommunications was a proof-of-capability demonstration of artificial intelligence as applied to the problem of real time monitoring functions in planetary mission operations. An overview of the design and functional description of the SHARP system is also presented as it was applied to Voyager.

  7. Soviet space flight: the human element.

    Science.gov (United States)

    Garshnek, V

    1989-07-01

    Building on past experience and knowledge, the Soviet manned space flight effort has become broad, comprehensive, and forward-looking. Their long-running space station program has provided the capabilities to investigate long-term effects of microgravity on human physiology and behavior, and test various countermeasures against microgravity-induced physiological deconditioning. Since the beginning of Soviet manned space flight, the biomedical training and preparation of cosmonauts has evolved from a process that increased human tolerance to space flight factors, to a system of interrelated measures to prepare cosmonauts physically and psychologically to live and work in space. Currently, the Soviet Union is constructing a multimodular space station, the Mir. With the emergence of dedicated laboratory modules, the Soviets have begun the transition from small-scale experimental research to large-scale production activities and specialized scientific work in space. In the future, additional laboratory modules will be added, including one dedicated to biomedical research, called the "Medilab." The longest manned space flight to date (326 d) has been completed by the Soviets. The biomedical effects of previous long-duration flights, and perhaps those of still greater length, may contribute important insight into the possibility of extended missions beyond Earth, such as a voyage to Mars.

  8. Implementation of the Master Plan Activities in Serayu River Voyage (SRV Within the Framework of Tourism Development in Banyumas Regency

    Directory of Open Access Journals (Sweden)

    Imam Pamungkas

    2015-02-01

    Full Text Available The Master Plan Activity of Serayu River Voyage (SRV for tourism development in Banyumas Regency were expected to be completed within five years from 2008 to 2012, but during the period until 2013, most programs and activities have not been implemented. The results showed that the Master Plan of SRV in the framework of tourism development in Banyumas Regency has not been implemented properly. The cause is the absence of good coordination between agencies, the lack programs and activities integration, supporting documents have not been revised, absence of good socialization, and the lack of private sector contribution. The factors that constrain and support implementation of the Master Plan is described as follows. Supporting factors: competent human resources (implementor already available at the managerial level and have intellectual tourism, it is only need to add personnel in the sector of culture; the availability of adequate budget; institutions that have been effective and efficient; High community response; High commitment of Banyumas Regent and cooperation related parties (stakeholders; and natural conditions of Serayu tend to calm and the river slope condition is small. The constrain factors: regulatory policies; integration of programs and activities; coordination and socialization implied sectoral ego that need to be addressed. Keywords : implementation, master plan, Serayu River Voyage, human resources, regulation

  9. Voyager observations in the distant heliosheath: An analogy with ISEE-3 observations in the deep geomagnetic tail

    CERN Document Server

    Richardson, Ian G

    2016-01-01

    We suggest an analogy between energetic particle and magnetic field observations made by the Voyager 1 spacecraft in the distant heliosheath at 122 AU in August 2012, and those made in the distant geomagnetic tail by the ISEE 3 spacecraft in 1982-1983, despite large differences in the time and distance scales. The analogy suggests that in August, 2012, Voyager 1 may not have moved from the anomalous cosmic ray (ACR)-dominated heliosheath into the interstellar medium but into a region equivalent to the "lobes" of the geomagnetic tail, composed of heliospheric field lines which have reconnected with the interstellar medium beyond the spacecraft and so are open to the entry of cosmic rays, while heliospheric particles (e.g., ACRs) are free to escape, and which maintain a ~Parker spiral configuration. The heliopause, analogous to the magnetopause forming the outer boundary of the lobes, may then lie beyond this so-called "heliocliff". Even if this analogy is incorrect, the remarkable similarities between the ener...

  10. Fitting the Low Energy Spectra of Cosmic Ray Primary Nuclei from C to Fe as Measured on Voyager 1

    CERN Document Server

    Webber, W R

    2016-01-01

    The intensities of the low energy part of the spectra of primary cosmic ray nuclei including C, O, Ne, Mg, Si and Fe measured by Voyager 1 beyond the heliopause are deficient relative to the spectra measured at energies above ~100 MeV/nuc as calculated using a standard Leaky Box Model with the path length a function of rigidity. Modifications to the normal exponential distribution of path lengths at a single rigidity as is used in a simple LBM will provide a good fit to this new Voyager 1 data at low energies. These modifications, sometimes called a truncation, lead to a deficiency of short path lengths relative to an exponential distribution. This deficiency in the intensities can be described by a truncation parameter = 0.12. This modification can be produced in several ways including a non-uniform local distribution of cosmic ray sources. A uniform source distribution in the galactic plane that is deficient in sources within 0.2-0.4 Kpc of the Sun is indicated by the data. Further studies of these low ener...

  11. Voyager observations in the distant heliosheath: An analogy with ISEE-3 observations in the deep geomagnetic tail

    Science.gov (United States)

    Richardson, Ian G.

    2017-08-01

    We suggest an analogy between energetic particle and magnetic field observations made by the Voyager 1 spacecraft in the distant heliosheath at 122 AU in August 2012, and those made in the distant geomagnetic tail by the ISEE 3 spacecraft in 1982-1983, despite large differences in the time and distance scales. The analogy suggests that in August, 2012, Voyager 1 may not have moved from the anomalous cosmic ray (ACR)-dominated heliosheath into the interstellar medium but into a region equivalent to the ;lobes; of the geomagnetic tail, composed of heliospheric field lines which have reconnected with the interstellar medium beyond the spacecraft and so are open to the entry of cosmic rays, while heliospheric particles (e.g., ACRs) are free to escape, and which maintain a ∼Parker spiral configuration. The heliopause, analogous to the magnetopause forming the outer boundary of the lobes, may then lie beyond this so-called ;heliocliff;. Even if this analogy is incorrect, the remarkable similarities between the energetic particle and magnetic field observations in these very different regions are worth noting.

  12. The abundance and distribution of water vapor in the Jovian troposphere as inferred from Voyager IRIS observations

    Science.gov (United States)

    Carlson, Barbara E.; Lacis, Andrew A.; Rossow, William B.

    1992-01-01

    The Voyager IRIS spectra of the Jovian North Equatorial Belt (NEB) hot spots are reanalyzed using a radiative transfer model which includes the full effects of anisotropic multiple scattering by clouds. The atmospheric model includes the three thermochemically predicted cloud layers, NH3, NH4SH, and H2O. Spectrally dependent cloud extinction is modeled using Mie theory and the refractive indices of NH3 ice, NH4SH ice, water, and H2O ice. The upper tropospheric temperature profile, gas abundances, height-dependent parahydrogen profile, and vertical distribution of NH3 cloud opacity are retrieved from an analysis of the far-infrared (180-1200/cm) IRIS observations. With these properties constrained, the 5-micron (1800-2300/cm) observations are analyzed to determine the atmospheric and cloud structure of the deeper atmosphere (P of greater than 1.5 bars). The results show that the abundance of water is at least 1.5 times solar with 2 times solar (0.00276 mixing ratio relative to H2) providing the best-fit to the Voyager IRIS hot spot observations.

  13. Fantastic voyage: live long enough to live forever. The science behind radical life extension questions and answers.

    Science.gov (United States)

    Kurzweil, Ray; Grossman, Terry

    2009-01-01

    Putting an end to human aging is now becoming a reality, and immortality is no longer just a dream. Through what we are calling "Fantastic Voyage," we provide a guide to achieving life extension through various means, thereby slowing down aging and disease processes. The three components of Fantastic Voyage are: Bridge One--Aggressively applying today's knowledge. Bridge Two--Putting biotechnology, such as gene technologies, to use with therapeutic cloning and rejuvenation medicine. Bridge Three--Putting nanotechnology to use by developing a means to rebuild our bodies and brains with nanobots. Many of these technology solutions can be simulated today through the use of targeted supplements, designed to address the specific needs of an individual, such as insulin resistance, cholesterol and homocysteine levels, and inflammation. To slow aging now, we propose a program of supplementing aggressively, eating foods that impede aging and disease processes, and reversing inflammation through diet. We also provide guidance to customize each program to the specific needs of the individual. Emerging technologies in rational drug design, tissue engineering, gene therapy, and nanobots (among others) promise a future of automated life extension. The use of such technologies, and the resulting dramatic increases in productivity in all areas of human endeavor, will enable us to live in a world in which all our physical needs can be met.

  14. Hard Probes at ATLAS

    CERN Document Server

    Citron, Z; The ATLAS collaboration

    2014-01-01

    The ATLAS collaboration has measured several hard probe observables in Pb+Pb and p+Pb collisions at the LHC. These measurements include jets which show modification in the hot dense medium of heavy ion collisions as well as color neutral electro-weak bosons. Together, they elucidate the nature of heavy ion collisions.

  15. Endocavity Ultrasound Probe Manipulators.

    Science.gov (United States)

    Stoianovici, Dan; Kim, Chunwoo; Schäfer, Felix; Huang, Chien-Ming; Zuo, Yihe; Petrisor, Doru; Han, Misop

    2013-06-01

    We developed two similar structure manipulators for medical endocavity ultrasound probes with 3 and 4 degrees of freedom (DoF). These robots allow scanning with ultrasound for 3-D imaging and enable robot-assisted image-guided procedures. Both robots use remote center of motion kinematics, characteristic of medical robots. The 4-DoF robot provides unrestricted manipulation of the endocavity probe. With the 3-DoF robot the insertion motion of the probe must be adjusted manually, but the device is simpler and may also be used to manipulate external-body probes. The robots enabled a novel surgical approach of using intraoperative image-based navigation during robot-assisted laparoscopic prostatectomy (RALP), performed with concurrent use of two robotic systems (Tandem, T-RALP). Thus far, a clinical trial for evaluation of safety and feasibility has been performed successfully on 46 patients. This paper describes the architecture and design of the robots, the two prototypes, control features related to safety, preclinical experiments, and the T-RALP procedure.

  16. One-Probe Search

    DEFF Research Database (Denmark)

    Östlin, Anna; Pagh, Rasmus

    2002-01-01

    We consider dictionaries that perform lookups by probing a single word of memory, knowing only the size of the data structure. We describe a randomized dictionary where a lookup returns the correct answer with probability 1 - e, and otherwise returns don't know. The lookup procedure uses an expan...

  17. One-Probe Search

    DEFF Research Database (Denmark)

    Östlin, Anna; Pagh, Rasmus

    2002-01-01

    We consider dictionaries that perform lookups by probing a single word of memory, knowing only the size of the data structure. We describe a randomized dictionary where a lookup returns the correct answer with probability 1 - e, and otherwise returns don't know. The lookup procedure uses an expan...

  18. (SC)RMI: A (S)emi-(C)lassical (R)elativistic (M)otion (I)integrator, to model the orbits of space probes around the Earth and other planets

    CERN Document Server

    Pireaux, S; Rosenblatt, P

    2006-01-01

    Today, the motion of spacecrafts is still described according to the classical Newtonian equations plus the so-called "relativistic corrections", computed with the required precision using the Post-(Post-)Newtonian formalism. The current approach, with the increase of tracking precision (Ka-Band Doppler, interplanetary lasers) and clock stabilities (atomic fountains) is reaching its limits in terms of complexity, and is furthermore error prone. In the appropriate framework of General Relativity, we study a method to numerically integrate the native relativistic equations of motion for a weak gravitational field, also taking into account small non-gravitational forces. The latter are treated as perturbations, in the sense that we assume that both the local structure of space-time is not modified by these forces, and that the unperturbed satellite motion follows the geodesics of the local space-time. The use of a symplectic integrator to compute the unperturbed geodesic motion insures the constancy of the norm ...

  19. Creating and Probing Graphene Electron Optics with Local Scanning Probes

    Science.gov (United States)

    Stroscio, Joseph

    Ballistic propagation and the light-like dispersion of graphene charge carriers make graphene an attractive platform for optics-inspired graphene electronics where gate tunable potentials can control electron refraction and transmission. In analogy to optical wave propagation in lenses, mirrors and metamaterials, gate potentials can be used to create a negative index of refraction for Veselago lensing and Fabry-Pérot interferometers. In circular geometries, gate potentials can induce whispering gallery modes (WGM), similar to optical and acoustic whispering galleries albeit on a much smaller length scale. Klein scattering of Dirac carriers plays a central role in determining the coherent propagation of electron waves in these resonators. In this talk, I examine the probing of electron resonators in graphene confined by linear and circular gate potentials with the scanning tunneling microscope (STM). The tip in the STM tunnel junction serves both as a tunable local gate potential, and as a probe of the graphene states through tunneling spectroscopy. A combination of a back gate potential, Vg, and tip potential, Vb, creates and controls a circular pn junction that confines the WGM graphene states. The resonances are observed in two separate channels in the tunneling spectroscopy experiment: first, by directly tunneling into the state at the bias energy eVb, and, second, by tunneling from the resonance at the Fermi level as the state is gated by the tip potential. The second channel produces a fan-like set of WGM peaks, reminiscent of the fringes seen in planar geometries by transport measurements. The WGM resonances split in a small applied magnetic field, with a large energy splitting approaching the WGM spacing at 0.5 T. These results agree well with recent theory on Klein scattering in graphene electron resonators. This work is done in collaboration with Y. Zhao, J. Wyrick, F.D. Natterer, J. F. Rodriquez-Nieva, C. Lewandoswski, K. Watanabe, T. Taniguchi, N. B

  20. Voyage aux Enfers ou rêve de jeune-fille ?Les révélations curieuses de la Fille dans le Gascon extravagant

    Directory of Open Access Journals (Sweden)

    Sophie Houdard

    2007-10-01

    space with possession. The representation denounces the dangerous power of the fable of demonic possession by situating it in a fictional medium. We will see how the so-called « Young woman » and the story of her Voyage into Hell partake of this critical representation by way of creating a narrative of rare ambiguity.

  1. Constructing Phase Space Distributions within the Heliosheath

    Science.gov (United States)

    Roelof, E. C.

    2014-12-01

    The key function in the description of the dynamics of the heliosheath (HS) is the phase space distribution (PSD) of the protons, i.e., how the interaction between the thermal and non-thermal (heated pick-up) proton populations evolves from the termination shock to the heliopause (HP) in this high-beta plasma. Voyager 1 found the heliopause to be essentially a (compound) magnetic separatrix, because the intensity of the non-thermal particle population became undetectably small beyond the HP, whereas the anisotropy characteristics of the galactic cosmic rays were consistent with no re-entry of the magnetic field lines into the HS (at either end). This paper attempts to synthesize in situ observations from Voyagers 1 and 2 (thermal plasma, magnetic field, energetic ions, and cosmic rays) with global ENA images from IBEX and Cassini/INCA into a self-consistent representation of the PSD within the noseward HS from thermal energies to several MeV/nuc. The interpretation of the ENA images requires assumptions on the global behavior of the bulk plasma flow throughout the HS that are self-consistent with all the available data (e.g., the spatial and energy dependence of the IBEX ribbon), because the Compton-Getting effects produced by the flows strongly affect the intensities (and thereby the partial densities and pressures) inferred from the ENA images.

  2. EDITORIAL: Probing the nanoworld Probing the nanoworld

    Science.gov (United States)

    Miles, Mervyn

    2009-10-01

    In nanotechnology, it is the unique properties arising from nanometre-scale structures that lead not only to their technological importance but also to a better understanding of the underlying science. Over the last twenty years, material properties at the nanoscale have been dominated by the properties of carbon in the form of the C60 molecule, single- and multi-wall carbon nanotubes, nanodiamonds, and recently graphene. During this period, research published in the journal Nanotechnology has revealed the amazing mechanical properties of such materials as well as their remarkable electronic properties with the promise of new devices. Furthermore, nanoparticles, nanotubes, nanorods, and nanowires from metals and dielectrics have been characterized for their electronic, mechanical, optical, chemical and catalytic properties. Scanning probe microscopy (SPM) has become the main characterization technique and atomic force microscopy (AFM) the most frequently used SPM. Over the past twenty years, SPM techniques that were previously experimental in nature have become routine. At the same time, investigations using AFM continue to yield impressive results that demonstrate the great potential of this powerful imaging tool, particularly in close to physiological conditions. In this special issue a collaboration of researchers in Europe report the use of AFM to provide high-resolution topographical images of individual carbon nanotubes immobilized on various biological membranes, including a nuclear membrane for the first time (Lamprecht C et al 2009 Nanotechnology 20 434001). Other SPM developments such as high-speed AFM appear to be making a transition from specialist laboratories to the mainstream, and perhaps the same may be said for non-contact AFM. Looking to the future, characterisation techniques involving SPM and spectroscopy, such as tip-enhanced Raman spectroscopy, could emerge as everyday methods. In all these advanced techniques, routinely available probes will

  3. Space of Spaces

    CERN Document Server

    Anderson, Edward

    2014-01-01

    Wheeler emphasized the study of Superspace - the space of 3-geometries on a spatial manifold of fixed topology. This is a configuration space for GR; knowledge of configuration spaces is useful as regards dynamics and QM.In this Article I consider furthmore generalized configuration spaces to all levels within the conventional `equipped sets' paradigm of mathematical structure used in fundamental Theoretical Physics. This covers A) the more familiar issue of topology change in the sense of topological manifolds (tied to cobordisms), including via pinched manifolds. B) The less familiar issue of not regarding as fixed the yet deeper levels of structure: topological spaces themselves (and their metric space subcase), collections of subsets and sets. Isham has previously presented quantization schemes for a number of these. I consider some classical preliminaries for this program, aside from the most obvious (classical dynamics for each). Rather, I provide I) to all levels Relational and Background Independence ...

  4. Optical Mach Probe Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Michigan Aerospace Corporation (MAC) proposes to advance NASA's nonintrusive spatially- and temporally-resolved Interferometric Rayleigh Scattering (IRS) technology...

  5. Calibration Fixture For Anemometer Probes

    Science.gov (United States)

    Lewis, Charles R.; Nagel, Robert T.

    1993-01-01

    Fixture facilitates calibration of three-dimensional sideflow thermal anemometer probes. With fixture, probe oriented at number of angles throughout its design range. Readings calibrated as function of orientation in airflow. Calibration repeatable and verifiable.

  6. The twenty-first century in space

    CERN Document Server

    Evans, Ben

    2015-01-01

    This final entry in the History of Human Space Exploration mini-series by Ben Evans continues with an in-depth look at the latter part of the 20th century and the start of the new millennium. Picking up where Partnership in Space left off, the story commemorating the evolution of manned space exploration unfolds in further detail. More than fifty years after Yuri Gagarin’s pioneering journey into space, Evans extends his overview of how that momentous voyage continued through the decades which followed. The Twenty-first Century in Space, the sixth book in the series, explores how the fledgling partnership between the United States and Russia in the 1990s gradually bore fruit and laid the groundwork for today’s International Space Station. The narrative follows the convergence of the Shuttle and Mir programs, together with standalone missions, including servicing the Hubble Space Telescope, many of whose technical and human lessons enabled the first efforts to build the ISS in orbit. The book also looks to...

  7. Pico Reentry Probes: Affordable Options for Reentry Measurements and Testing

    Science.gov (United States)

    Ailor, William H.; Kapoor, Vinod B.; Allen, Gay A., Jr.; Venkatapathy, Ethiraj; Arnold, James O.; Rasky, Daniel J.

    2005-01-01

    It is generally very costly to perform in-space and atmospheric entry experiments. This paper presents a new platform - the Pico Reentry Probe (PREP) - that we believe will make targeted flight-tests and planetary atmospheric probe science missions considerably more affordable. Small, lightweight, self-contained, it is designed as a "launch and forget" system, suitable for experiments that require no ongoing communication with the ground. It contains a data recorder, battery, transmitter, and user-customized instrumentation. Data recorded during reentry or space operations is returned at end-of-mission via transmission to Iridium satellites (in the case of earth-based operations) or a similar orbiting communication system for planetary missions. This paper discusses possible applications of this concept for Earth and Martian atmospheric entry science. Two well-known heritage aerodynamic shapes are considered as candidates for PREP: the shape developed for the Planetary Atmospheric Experiment Test (PAET) and that for the Deep Space II Mars Probe.

  8. Phoenix Conductivity Probe Inserted in Martian Soil

    Science.gov (United States)

    2008-01-01

    This series of six images from the Robotic Arm Camera on NASA's Phoenix Mars Lander records the first time that the four spikes of the lander's thermal and electrical conductivity probe were inserted into Martian soil. The images were taken on July 8, 2008, during the Phoenix mission's 43rd Martian day, or sol, since landing. The insertion visible from the shadows cast on the ground on that sol was a validation test of the procedure. The spikes on the probe are about 1.5 centimeters or half an inch long. The science team will use the probe tool to assess how easily heat and electricity move through the soil from one spike to another. Such measurements can provide information about frozen or unfrozen water in the soil. The probe is mounted on the 'knuckle' of Phoenix's Robotic Arm. It has already been used for assessing water vapor in the atmosphere when it is held above the ground. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  9. Probing properties of cold radiofrequency plasma with polymer probe

    Science.gov (United States)

    Bormashenko, E.; Chaniel, G.; Multanen, V.

    2015-01-01

    The probe intended for the characterization of cold plasma is introduced. The probe allows the estimation of Debye length of cold plasma. The probe is based on the pronounced modification of surface properties (wettability) of polymer films by cold plasmas. The probe was tested with the cold radiofrequency inductive air plasma discharge. The Debye length and the concentration of charge carriers were estimated for various gas pressures. The reported results coincide reasonably with the corresponding values established by other methods. The probe makes possible measurement of characteristics of cold plasmas in closed chambers.

  10. Probing Properties of Cold Radiofrequency Plasma with Polymer Probe

    CERN Document Server

    Bormashenko, Edward; Multanen, Victor

    2014-01-01

    The probe intended for the characterization of cold plasma is introduced. The probe allows estimation of the Debye length of the cold plasma. The probe is based on the pronounced modification of surface properties (wettability) of polymer films by cold plasmas. The probe was tested with the cold radiofrequency inductive air plasma discharge. The Debye length and the concentration of charge carriers were estimated for various gas pressures. The reported results coincide reasonably with the corresponding values established by other methods. The probe makes possible measurement of characteristics of cold plasmas in closed chambers.

  11. Atom probe tomography today

    OpenAIRE

    Alfred Cerezo; Peter H. Clifton; Mark J. Galtrey; Humphreys, Colin J.; Kelly, Thomas. F.; David J. Larson; Sergio Lozano-Perez; Marquis, Emmanuelle A.; Oliver, Rachel A.; Gang Sha; Keith Thompson; Mathijs Zandbergen; Roger L. Alvis

    2007-01-01

    This review aims to describe and illustrate the advances in the application of atom probe tomography that have been made possible by recent developments, particularly in specimen preparation techniques (using dual-beam focused-ion beam instruments) but also of the more routine use of laser pulsing. The combination of these two developments now permits atomic-scale investigation of site-specific regions within engineering alloys (e.g. at grain boundaries and in the vicinity of cracks) and also...

  12. 33 CFR 151.2037 - If my vessel cannot conduct ballast water management practices because of its voyage and/or...

    Science.gov (United States)

    2010-07-01

    ... ballast water management practices because of its voyage and/or safety concerns, will I be prohibited from..., MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Ballast Water Management for Control of Nonindigenous Species in Waters of the United States § 151.2037 If my vessel cannot conduct ballast water...

  13. Connecting the World in the Spirit of Zheng He--Boeing 777-200LR Worldliner Commemorates 600th Anniversary of Zheng He's Voyages

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

      The Boeing [NYSE:BA] 777-200LR Worldliner, the world's longest range commercial airplane, was officially named "Zheng He" at Beijing's Capital International Airport during a ceremony to commemorate the seven incredible voyages by the great Chinese navigator and explorer Zheng He.……

  14. Connecting the World in the Spirit of Zheng He--Boeing 777-200LR Worldliner Commemorates 600th Anniversary of Zheng He's Voyages

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ The Boeing [NYSE:BA] 777-200LR Worldliner, the world's longest range commercial airplane, was officially named "Zheng He" at Beijing's Capital International Airport during a ceremony to commemorate the seven incredible voyages by the great Chinese navigator and explorer Zheng He.

  15. Voyager: Reading and Writing for Today's Adults. Levels 7 and 8 Teacher's Resource Guide [and] Student Book [and] Student Workbook [and] Puzzles [and] Vocabulary Workbook.

    Science.gov (United States)

    1999

    This document contains the 9 publications constituting the fourth stage of the Voyager program, which is a four-stage program that utilizes contemporary content and instructional approaches to teach the reading, writing, critical thinking, and communication skills that adults need in today's world and to take adult learners from the beginning…

  16. Darwin’s legacy to rove beetles (Coleoptera, Staphylinidae: A new genus and a new species, including materials collected on the Beagle’s voyage

    Directory of Open Access Journals (Sweden)

    Stylianos Chatzimanolis

    2014-02-01

    Full Text Available A species of xanthopygine rove beetles is described and figured here as Darwinilus sedarisi gen. n. and sp. n. The holotype was collected by Charles Darwin in Bahía Blanca, Argentina on the Beagle’s voyage. The contributions of Charles Darwin to rove beetle systematics are summarized briefly.

  17. Einstein Inflationary Probe (EIP)

    Science.gov (United States)

    Hinshaw, Gary

    2004-01-01

    I will discuss plans to develop a concept for the Einstein Inflation Probe: a mission to detect gravity waves from inflation via the unique signature they impart to the cosmic microwave background (CMB) polarization. A sensitive CMB polarization satellite may be the only way to probe physics at the grand-unified theory (GUT) scale, exceeding by 12 orders of magnitude the energies studied at the Large Hadron Collider. A detection of gravity waves would represent a remarkable confirmation of the inflationary paradigm and set the energy scale at which inflation occurred when the universe was a fraction of a second old. Even a strong upper limit to the gravity wave amplitude would be significant, ruling out many common models of inflation, and pointing to inflation occurring at much lower energy, if at all. Measuring gravity waves via the CMB polarization will be challenging. We will undertake a comprehensive study to identify the critical scientific requirements for the mission and their derived instrumental performance requirements. At the core of the study will be an assessment of what is scientifically and experimentally optimal within the scope and purpose of the Einstein Inflation Probe.

  18. Nanoscale thermal probing

    Directory of Open Access Journals (Sweden)

    Yanan Yue

    2012-03-01

    Full Text Available Nanoscale novel devices have raised the demand for nanoscale thermal characterization that is critical for evaluating the device performance and durability. Achieving nanoscale spatial resolution and high accuracy in temperature measurement is very challenging due to the limitation of measurement pathways. In this review, we discuss four methodologies currently developed in nanoscale surface imaging and temperature measurement. To overcome the restriction of the conventional methods, the scanning thermal microscopy technique is widely used. From the perspective of measuring target, the optical feature size method can be applied by using either Raman or fluorescence thermometry. The near-field optical method that measures nanoscale temperature by focusing the optical field to a nano-sized region provides a non-contact and non-destructive way for nanoscale thermal probing. Although the resistance thermometry based on nano-sized thermal sensors is possible for nanoscale thermal probing, significant effort is still needed to reduce the size of the current sensors by using advanced fabrication techniques. At the same time, the development of nanoscale imaging techniques, such as fluorescence imaging, provides a great potential solution to resolve the nanoscale thermal probing problem.

  19. Nine New Fluorescent Probes

    Science.gov (United States)

    Lin, Tsung-I.; Jovanovic, Misa V.; Dowben, Robert M.

    1989-06-01

    Absorption and fluorescence spectroscopic studies are reported here for nine new fluorescent probes recently synthesized in our laboratories: four pyrene derivatives with substituents of (i) 1,3-diacetoxy-6,8-dichlorosulfonyl, (ii) 1,3-dihydroxy-6,8-disodiumsulfonate, (iii) 1,3-disodiumsulfonate, and (iv) l-ethoxy-3,6,8-trisodiumsulfonate groups, and five [7-julolidino] coumarin derivatives with substituents of (v) 3-carboxylate-4-methyl, (vi) 3- methylcarboxylate, (vii) 3-acetate-4-methyl, (viii) 3-propionate-4-methyl, and (ix) 3-sulfonate-4-methyl groups. Pyrene compounds i and ii and coumarin compounds v and vi exhibit interesting absorbance and fluorescence properties: their absorption maxima are red shifted compared to the parent compound to the blue-green region, and the band width broadens considerably. All four blue-absorbing dyes fluoresce intensely in the green region, and the two pyrene compounds emit at such long wavelengths without formation of excimers. The fluorescence properties of these compounds are quite environment-sensitive: considerable spectral shifts and fluorescence intensity changes have been observed in the pH range from 3 to 10 and in a wide variety of polar and hydrophobic solvents with vastly different dielectric constants. The high extinction and fluorescence quantum yield of these probes make them ideal fluorescent labeling reagents for proteins, antibodies, nucleic acids, and cellular organelles. The pH and hydrophobicity-dependent fluorescence changes can be utilized as optical pH and/or hydrophobicity indicators for mapping environmental difference in various cellular components in a single cell. Since all nine probes absorb in the UV, but emit at different wavelengths in the visible, these two groups of compounds offer an advantage of utilizing a single monochromatic light source (e.g., a nitrogen laser) to achieve multi-wavelength detection for flow cytometry application. As a first step to explore potential application in

  20. Gravity Probe B data system description

    Science.gov (United States)

    Bennett, Norman R.

    2015-11-01

    The Gravity Probe B data system, developed, integrated, and tested by Lockheed Missiles & Space Company, and later Lockheed Martin Corporation, included flight and ground command, control, and communications software. The development was greatly facilitated, conceptually and by the transfer of key personnel, through Lockheed’s earlier flight and ground test software development for the Hubble Space Telescope (HST). Key design challenges included the tight mission timeline (17 months, 9 days of on-orbit operation), the need to tune the system once on-orbit, and limited 2 Kbps real-time data rates and ground asset availability. The result was a completely integrated space vehicle and Stanford mission operations center, which successfully collected and archived 97% of the ‘guide star valid’ data to support the science analysis. Lessons learned and incorporated from the HST flight software development and on-orbit support experience, and Lockheed’s independent research and development effort, will be discussed.

  1. Surface-sensitive conductivity measurement using a micro multi-point probe approach

    DEFF Research Database (Denmark)

    Perkins, Edward; Barreto, Lucas; Wells, Justin

    2013-01-01

    An instrument for microscale electrical transport measurements in ultra-high vacuum is presented. The setup is constructed around collinear lithographically-created multi-point probes with a contact spacing down to 500 nm. Most commonly, twelve-point probes are used. These probes are approached...... measurements with an equidistant four-point probe for a wide range of contact spacings. In this way, it is possible to distinguish between bulk-like and surface-like conduction. The paper describes the design of the instrument and the approach to data and error analysis. Application examples are given...

  2. A note on the ring current in Saturn’s magnetosphere: Comparison of magnetic data obtained during the Pioneer-11 and Voyager-1 and -2 fly-bys

    Directory of Open Access Journals (Sweden)

    E. J. Bunce

    Full Text Available We examine the residual (measured minus internal magnetic field vectors observed in Saturn’s magnetosphere during the Pioneer-11 fly-by in 1979, and compare them with those observed during the Voyager-1 and -2 fly-bys in 1980 and 1981. We show for the first time that a ring current system was present within the magnetosphere during the Pioneer-11 encounter, which was qualitatively similar to those present during the Voyager fly-bys. The analysis also shows, however, that the ring current was located closer to the planet during the Pioneer-11 encounter than during the comparable Voyager-1 fly-by, reflecting the more com-pressed nature of the magnetosphere at the time. The residual field vectors have been fit using an adaptation of the current system proposed for Jupiter by Connerney et al. (1981a. A model that provides a reasonably good fit to the Pioneer-11 Saturn data extends radially between 6.5 and 12.5 RS (compared with a noon-sector magnetopause distance of 17 RS, has a north-south extent of 4 RS, and carries a total current of 9.6 MA. A corresponding model that provides a qualitatively similar fit to the Voyager data, determined previously by Connerney et al. (1983, extends radially between 8 and 15.5 RS (compared with a noon-sector magnetopause distance for Voyager-1 of 23–24 RS, has a north-south extent of 6 RS, and carries a total current of 11.5 MA.

    Key words. Magnetospheric physics (current systems, magnetospheric configuration and dynamics, planetary magnetospheres

  3. Development of Mackintosh Probe Extractor

    Science.gov (United States)

    Rahman, Noor Khazanah A.; Kaamin, Masiri; Suwandi, Amir Khan; Sahat, Suhaila; Jahaya Kesot, Mohd

    2016-11-01

    Dynamic probing is a continuous soil investigation technique, which is one of the simplest soil penetration test. It basically consist of repeatedly driving a metal tipped probe into the ground using a drop weight of fixed mass and travel. Testing was carried out continuously from ground level to the final penetration depth. Once the soil investigation work done, it is difficult to pull out the probe rod from the ground, due to strong soil structure grip against probe cone and prevent the probe rod out from the ground. Thus, in this case, a tool named Extracting Probe was created to assist in the process of retracting the probe rod from the ground. In addition, Extracting Probe also can reduce the time to extract the probe rod from the ground compare with the conventional method. At the same time, it also can reduce manpower cost because only one worker involve to handle this tool compare with conventional method used two or more workers. From experiment that have been done we found that the time difference between conventional tools and extracting probe is significant, average time difference is 155 minutes. In addition the extracting probe can reduce manpower usage, and also labour cost for operating the tool. With all these advantages makes this tool has the potential to be marketed.

  4. Characteristics of type III bursts in the solar wind from simultaneous observations on board ISEE-3 and Voyager

    Science.gov (United States)

    Lecacheux, A.; Steinberg, J.-L.; Hoang, S.; Dulk, G. A.

    1989-01-01

    The properties of solar type III bursts observed aboard ISEE-3 and Voyager that originate behind the sun are analyzed and compared to those originating on the near side. The measurement of the burst parameters and the correction for proximity effects are described. The diminution of flux densities, the increase of source sizes, the difference of source azimuths and elevations, the change of spectral properties, and the anomalous delays in burst arrival time at one spacecraft relative to another are determined. Many of the observations imply that the beaming of type III radiation is much more widespread at all frequencies than has been derived from statistical studies. The effective beam appears to consist of at least two components: a Gaussian core of half width about 60 deg, and a very broad halo that extends to 180 deg with an amplitude of a few percent.

  5. Voyages of a successful text. The Dialogi of Gregory the Great in Medieval Sicily (XII-XIV Century

    Directory of Open Access Journals (Sweden)

    Rossana Barcellona

    2013-10-01

    Full Text Available This essay reconstructs two “Sicilian chapters” of great success from the Dialogi by Gregorius Magnus which were enjoyed in the medieval era. These are the legend of Placido (Placido is a Benedict's young disciple mentioned in the Dialogi, which has Sicily as a background, as recounted by Pietro, Deacon of Montecassino between the XI and the XII centuries, and the Sicilian vulgarization of the work, carried out by Giovanni Campolo in the first half of the XIV century. The literary voyage of Placido and the work of Campolo are two excellent examples of the circulation and the fruition of an exemplary and authoritative text. Each highlights the complex intricacy of religion, culture and politics in the various systems of power and in the various historical settings that the medieval age explored.

  6. Titan's atmosphere from Voyager infrared observations. III - Vertical contributions of hydrocarbons and nitriles near Titan's north pole

    Science.gov (United States)

    Coustenis, A.; Bezard, B.; Gautier, D.; Marten, A.; Samuelson, R.

    1991-01-01

    Voyager 1 IR spectra have been used to infer the Titan north polar region minor stratospheric constituents' temperature structure and vertical distribution. The mixing ratios of the species C4H2, C2H6, C3H4, HCN, HC3N, and C2N2 increase with altitude, implying upper stratosphere (and higher) formation regions. When compared with abundances obtained near the equator, it is found that the HC3N and C2N2 nitriles, together with such hydrocarbons as C2H4, C3H4, and C4H2, are substantially enhanced over the north polar region. A factor-of-2 (minimum) depletion of CO2 relative to the equator is noted; it is judged that current photochemical models are inadequate bases for interpretation of these observations.

  7. gestion d'une agence de voyage selon le modele client/serveur avec swing et mySQL

    OpenAIRE

    BELGACEM, Hicham; BOUAZZA, Mohammed Reda

    2014-01-01

    L’objectif de ce modeste travail est le développement d'une application Client/serveur pour la gestion d’une agence de voyage en se basant sur SWING et MySQL. Dans le premier chapitre de notre rapport nous avons présenté les outils misent en place pour la réalisation de notre application, en commençant par le langage Java utilisés sous Netbeans, MySQL pour la gestion de base de données et phpMyAdmin pour créer la BDD. Le deuxième chapitre est consacré à la présentation de notre...

  8. La place des ONG dans le changement social : voyage au pays du réel…

    OpenAIRE

    Bernard, Olivier; Martin, Boris

    2012-01-01

    « Pour que l’expertise déploie toute sa valeur et qu’au retour aucun doute ne soit laissé dans l’ombre, pour que ce voyage étrangle toute nostalgie et tout scrupule, il le faudra compréhensif, morcelé sous sa marche simple. » Victor Segalen, Équipée Les ONG ont longtemps fait profession (de foi) de poser des pansements sur les blessures du monde, de le faire bien et de mieux en mieux, mais de ne faire que cela. Elles revendiquaient ainsi de laisser aux associations de développement le soin de...

  9. Voyage dans le noir. Trous noirs, matière noire, énergie noire et antimatière

    CERN Document Server

    CERN. Geneva; Alvarez-Gaume, Luis; Grojean, Christophe

    2009-01-01

    Et si nous faisions avec les physiciens un voyage dans le noir ? De l'astrophysique à la physique des particules les trois noirs, la matière noire, l'énergie noire ou l’antimatière intriguent et fascinent. Que sont ces objets qui bousculent nos idées et qui véhiculent parfois des craintes irraisonnées? Luis Alvarez-Gaume, Michael Doser et Christophe Grojean, physiciens du CERN vous invitent à mettre en lumière (!) les constituants de base de la matière et à explorer les mystères de la physique contemporaine. Une soirée lumineuse pour éclairer des concepts et ne plus avoir peur du noir.

  10. Probe-based data storage

    CERN Document Server

    Koelmans, Wabe W; Abelmann, L

    2015-01-01

    Probe-based data storage attracted many researchers from academia and industry, resulting in unprecendeted high data-density demonstrations. This topical review gives a comprehensive overview of the main contributions that led to the major accomplishments in probe-based data storage. The most investigated technologies are reviewed: topographic, phase-change, magnetic, ferroelectric and atomic and molecular storage. Also, the positioning of probes and recording media, the cantilever arrays and parallel readout of the arrays of cantilevers are discussed. This overview serves two purposes. First, it provides an overview for new researchers entering the field of probe storage, as probe storage seems to be the only way to achieve data storage at atomic densities. Secondly, there is an enormous wealth of invaluable findings that can also be applied to many other fields of nanoscale research such as probe-based nanolithography, 3D nanopatterning, solid-state memory technologies and ultrafast probe microscopy.

  11. Vamos ao Brasil com Jules Verne?: processos editoriais e civilização nas Voyages Extraordinaires

    Directory of Open Access Journals (Sweden)

    Andréa Borges Leão

    2012-12-01

    Full Text Available No século XIX, uma rede de conhecimentos sobre as diferenças culturais dos povos americanos marcou a edição destinada à instrução e diversão da juventude francesa. Uma das 62 Voyages Extraordinaires de Jules Verne, publicadas por Pierre-Jules Hetzel, é ambientada entre o Peru e o Brasil: La Jangada, huit cents lieues sur l'Amazone (1881. Na produção de literatura juvenil que se desenvolve e expande no comércio transatlântico da livraria francesa, sobressai uma psicogênese do Brasil. Por esse ângulo, a via de análise aberta pelo sociólogo Norbert Elias ajudou a enfrentar o problema das emoções humanas, no romance de viagem, e a conceituar a atividade mimética no livro de ciência e recreação.In the 19th century, a net of knowledge about cultural differences of the populations of Americas imprint the edition assign to instruction and entertainment of the young French people. One of the 62 Voyages Extraordinaires of Jules Verne, published by Pierre-Jules Hetzel, is set between Peru and Brazil: La Jangada, huit cents lieues sur l'Amazone (Eight Hundred Leagues on the Amazon - 1881. Around the juvenile production that grows and expands in the transatlantic trade of the French bookstore, a psychogenesis of Brazil shines through. By this angle, the analytic way opened by the sociologist Norbert Elias helps to face the problem of the human emotions in the travel novel and also helps to consider the mimetic activity in the book of science and entertainment.

  12. Cook Island artifact geochemistry demonstrates spatial and temporal extent of pre-European interarchipelago voyaging in East Polynesia.

    Science.gov (United States)

    Weisler, Marshall I; Bolhar, Robert; Ma, Jinlong; St Pierre, Emma; Sheppard, Peter; Walter, Richard K; Feng, Yuexing; Zhao, Jian-Xin; Kirch, Patrick V

    2016-07-19

    The Cook Islands are considered the "gateway" for human colonization of East Polynesia, the final chapter of Oceanic settlement and the last major region occupied on Earth. Indeed, East Polynesia witnessed the culmination of the greatest maritime migration in human history. Perennial debates have critiqued whether Oceanic settlement was purposeful or accidental, the timing and pathways of colonization, and the nature and extent of postcolonization voyaging-essential for small founding groups securing a lifeline between parent and daughter communities. Centering on the well-dated Tangatatau rockshelter, Mangaia, Southern Cook Islands, we charted the temporal duration and geographic spread of exotic stone adze materials-essential woodworking tools found throughout Polynesia- imported for more than 300 y beginning in the early AD 1300s. Using a technique requiring only 200 mg of sample for the geochemical analysis of trace elements and isotopes of fine-grained basalt adzes, we assigned all artifacts to an island or archipelago of origin. Adze material was identified from the chiefly complex on the Austral Islands, from the major adze quarry complex on Tutuila (Samoa), and from the Marquesas Islands more than 2,400 km distant. This interaction is the only dated example of down-the-line exchange in central East Polynesia where intermediate groups transferred commodities attesting to the interconnectedness and complexity of social relations fostered during postsettlement voyaging. For the Cook Islands, this exchange may have lasted into the 1600s, at least a century later than other East Polynesian archipelagos, suggesting that interarchipelago interaction contributed to the later development of social hierarchies.

  13. Heliosheath ENA images by Cassini/INCA and in-situ hot plasma ion measurements by Voyagers

    Science.gov (United States)

    Krimigis, Stamatios; Roelof, Edmond; Mitchell, Donald; Decker, Robert; Dialynas, Konstantinos

    2016-07-01

    The advent of Energetic Neutral Atom (ENA) imaging, (the result of charge-exchange with energetic ions), has revealed the global nature of the heliosheath (HS) at both high ( > 5 keV, Cassini from 10 AU) and low (INCA (Ion and Neutral CAmera) since 2003 with a full image available since 2009, when IBEX global imaging observations also became available. The presence of the two Voyagers measuring ions locally in the HS contemporaneously with INCA global imaging through ENA in overlapping energy bands provides a powerful tool for examining the spatial, temporal, and spectral evolution of the source hot plasma ions and the global variability of the neutral component. Some of the key findings from the Voyagers and INCA measurements are as follows: (a) The HS contains a hot plasma population that carries a substantial part (30-50%) of the total pressure at E > 5 keV, the rest residing below that range, resulting in a beta (particle/magnetic pressure) always > 1, typically > 10. (b) The width of the HS in the direction of V1 is ˜~ 30 AU, but is thought to be larger (40-70 AU) in the southern ecliptic where V2 currently travels. (c) The ENA intensities at E > 5 keV exhibit a correlation with the solar cycle (SC) over the period 2003 to 2014, with minimum intensities in the anti-nose direction observed ˜~ 1.5 yrs after solar minimum followed by a recovery thereafter, and (d) The in situ ion measurements at V2 within the HS also show a similar SC dependence. The totality of the observations, together with the near-contemporaneous variability in intensities of ions in situ in the HS and ENA in the inner heliosphere suggests that the source of such emissions at E > 5 keV must reside in the HS. These observations constrain the shape of the HS and suggest configurations that are at some variance with current models.

  14. High Rate Tellecommunications for Mars Planetary and Proximity Ranges and other Deep-Space Missions-A Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space vehicles for deep space exploration rely on microwave and millimeter wave links for communication with earth stations. As the mission of space probes expands,...

  15. Atom probe tomography today

    Directory of Open Access Journals (Sweden)

    Alfred Cerezo

    2007-12-01

    Full Text Available This review aims to describe and illustrate the advances in the application of atom probe tomography that have been made possible by recent developments, particularly in specimen preparation techniques (using dual-beam focused-ion beam instruments but also of the more routine use of laser pulsing. The combination of these two developments now permits atomic-scale investigation of site-specific regions within engineering alloys (e.g. at grain boundaries and in the vicinity of cracks and also the atomic-level characterization of interfaces in multilayers, oxide films, and semiconductor materials and devices.

  16. Experimental probes of axions

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Aaron S.; /Fermilab

    2009-10-01

    Experimental searches for axions or axion-like particles rely on semiclassical phenomena resulting from the postulated coupling of the axion to two photons. Sensitive probes of the extremely small coupling constant can be made by exploiting familiar, coherent electromagnetic laboratory techniques, including resonant enhancement of transitions using microwave and optical cavities, Bragg scattering, and coherent photon-axion oscillations. The axion beam may either be astrophysical in origin as in the case of dark matter axion searches and solar axion searches, or created in the laboratory from laser interactions with magnetic fields. This note is meant to be a sampling of recent experimental results.

  17. Atom Probe Tomography 2012

    Science.gov (United States)

    Kelly, Thomas F.; Larson, David J.

    2012-08-01

    In the world of tomographic imaging, atom probe tomography (APT) occupies the high-spatial-resolution end of the spectrum. It is highly complementary to electron tomography and is applicable to a wide range of materials. The current state of APT is reviewed. Emphasis is placed on applications and data analysis as they apply to many fields of research and development including metals, semiconductors, ceramics, and organic materials. We also provide a brief review of the history and the instrumentation associated with APT and an assessment of the existing challenges in the field.

  18. Mobile Probing Kit

    DEFF Research Database (Denmark)

    Larsen, Jakob Eg; Sørensen, Lene Tolstrup; Sørensen, J.K.

    2007-01-01

    characterized as being highly nomadic and thus potential users of mobile and ubiquitous technologies. The methodology has been applied in the 1ST MAGNET Beyond project in order to obtain user needs and requirements in the process of developing pilot services. We report on the initial findings from applying......Mobile Probing Kit is a low tech and low cost methodology for obtaining inspiration and insights into user needs, requirements and ideas in the early phases of a system's development process. The methodology is developed to identify user needs, requirements and ideas among knowledge workers...

  19. Relative Position Determination between Deep-space Probes Based on Same Beam Phase-referencing Imaging Technique%深空探测器同波束相位参考成图相对定位方法

    Institute of Scientific and Technical Information of China (English)

    周欢; 童锋贤; 李海涛; 郑为民; 董光亮; 李培佳; 舒逢春

    2015-01-01

    针对我国后续深空探测任务中高精度相对定位需求,提出了采用天文同波束相位参考成图技术进行深空探测器相对定位的方法。首先建立适用于深空探测器信号特点的同波束相位参考成图相对定位模型,然后分析信号带宽和 UV 覆盖两个因素对测量精度的影响。最后利用我国 VLBI 观测网(CVN)在2013年15、20和21日接收的嫦娥三号着陆器和玉兔号巡视器下行同波束数据,处理得到了巡视器在5个环拍点相对着陆器的位置,验证了本文方法的可行性及其对探测器下行信号的强适应性。与视觉定位结果的对比表明,巡视器相对着陆器定位精度达到米级。%To meet the needs of high accuracy relative position determination in deep space explorations, a new method is proposed based on the same beam phase-referencing imaging technique that originates from the radio astronomy.Fi rstly,the same beam phase-referencing imaging measurement model for spacecraft positioning is bui lt.The very long basel ine interferometry (VLBI)imaging principle and the phase difference between two spacecrafts are derived.Then,two precision affecting factors are analyzed, including the signal bandwidth and the UV coverage.The di rty beams formed by different station numbers and different observation lengths with the Chinese interferometry network are simulated.Final ly,with the same beam observation data of the Chang’E-3 lander and rover from the Chinese VLBI network (CVN)on December 15,20 and 21,2013,the Yutu rover lunar surface positions are determined with accuracy of about 1 meter.The results show the feasibi l ity and high accuracy of this method,which is wel l-adapted to the spacecraft signals without special beacons.

  20. Campus Renewal in the 1980's: The New Voyage of the Beagle.

    Science.gov (United States)

    Hewitt, Clinton N.

    1982-01-01

    An approach to campus planning and renewal during declining enrollment is described. The process uses computer programing to integrate seven factors: building suitability to program, schedule, existing commitments, cost, effect on general use spaces, campus planning compatibility, and disturbance of current assignments of units not in the study.…

  1. Probing leptoquark production at IceCube

    CERN Document Server

    Anchordoqui, L A; Dumm, D G; Goldberg, H; Halzen, F; Anchordoqui, Luis A.; Canal, Carlos A. Garcia; Dumm, Daniel Gomez; Goldberg, Haim; Halzen, Francis

    2006-01-01

    We emphasize the inelasticity distribution of events detected at the IceCube neutrino telescope as an important tool for revealing new physics. This is possible because the unique energy resolution at this facility allows to separately assign the energy fractions for emergent muons and taus in neutrino interactions. As a particular example, we explore the possibility of probing second and third generation leptoquark parameter space (coupling and mass). We show that production of leptoquarks with masses \\agt 250 GeV and diagonal generation couplings of O(1) can be directly tested if the cosmic neutrino flux is at the Waxman-Bahcall level.

  2. Probing CP violation systematically in differential distributions

    CERN Document Server

    Durieux, Gauthier

    2015-01-01

    We revisit the topic of triple-product asymmetries which probe CP violation through differential distributions. We construct distributions with well-defined discrete symmetry properties and characterize the asymmetries formed upon them. It is stressed that the simplest asymmetries may not be optimal. We explore systematic generalizations having limited reliance on the process dynamics and phase-space parametrization. They exploit larger fractions of the information contained in differential distributions and may lead to increased sensitivities to CP violation. Our detailed treatment of the case of spinless four-body decays paves the way for further experimental studies.

  3. Phoenix's Probe Inserted in Martian Soil

    Science.gov (United States)

    2008-01-01

    The Phoenix Mars lander's robotic-arm camera took this image of the spacecraft's thermal and electrical-conductivity probe (TECP) inserted into Martian soil on day 149 of the mission. Phoenix landed on Mars' northern plains on May 25, 2008, landing. The robotic-arm camera acquired this image at 16:02:41 local solar time. The camera pointing was elevation -72.6986 degrees and azimuth 2.1093 degrees. The Phoenix mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  4. Modified electrical transport probe design for standard magnetometer

    CERN Document Server

    Assaf, Badih A; Wei, Peng; Katmis, Ferhat; Moodera, Jagadeesh S; Heiman, Don

    2012-01-01

    Making electrical transport measurements on a material is often a time consuming process that involves testing a large number of samples. It is thus inconvenient to wire up and rewire samples on to a sample probe. We therefore present a method of modifying Quantum Design's MPMS SQUID magnetometer transport probe that simplifies the process of sample mounting. One of the difficulties to overcome is the small diameter of the sample space. A small socket is designed and mounted on the probe so that various samples mounted on individual headers can be readily exchanged in the socket. We also present some test results on the topological insulator Bi2Te2Se using the modified probe.

  5. Dr. Harry Whelan With the Light Emitting Diode Probe

    Science.gov (United States)

    1999-01-01

    The red light from the Light Emitting Diode (LED) probe shines through the fingers of Dr. Harry Whelan, a pediatric neurologist at the Children's Hospital of Wisconsin in Milwaukee. Dr. Whelan uses the long waves of light from the LED surgical probe to activate special drugs that kill brain tumors. Laser light previously has been used for this type of surgery, but the LED light illuminates through all nearby tissues, reaching parts of tumors that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. Also, it can be used for hours at a time while still remaining cool to the touch. The probe was developed for photodynamic cancer therapy under a NASA Small Business Innovative Research Program grant. The program is part of NASA's Technology Transfer Department at the Marshall Space Flight Center.

  6. The Antartic Ice Borehole Probe

    Science.gov (United States)

    Behar, A.; Carsey, F.; Lane, A.; Engelhardt, H.

    2000-01-01

    The Antartic Ice Borehole Probe mission is a glaciological investigation, scheduled for November 2000-2001, that will place a probe in a hot-water drilled hole in the West Antartic ice sheet. The objectives of the probe are to observe ice-bed interactions with a downward looking camera, and ice inclusions and structure, including hypothesized ice accretion, with a side-looking camera.

  7. The accuracy of determining ion parameters by means of a cylindrical Langmuir probe

    Science.gov (United States)

    Georgieva, K. Ia.; Kirov, B. B.; Kraleva, L. Kh.

    A method is presented whereby a cylindrical Langmuir probe can be used to obtain an estimate of the concentration distribution of two prevalent kinds of ions in space plasmas when their masses are known. In many cases, the use of a Langmuir probe can thus compensate for the absence of a mass spectrometer. The probe can also be used as a backup if the data obtained by other instruments are not dependable.

  8. Micro scanning probes

    CERN Document Server

    Niblock, T

    2001-01-01

    This thesis covers the design methodology, theory, modelling, fabrication and evaluation of a Micro-Scanning-Probe. The device is a thermally actuated bimorph quadrapod fabricated using Micro Electro Mechanical Systems technology. A quadrapod is a structure with four arms, in this case a planar structure with the four arms forming a cross which is dry etched out of a silicon diaphragm. Each arm has a layer of aluminium deposited on it forming a bimorph. Through heating each arm actuation is achieved in the plane of the quadrapod and the direction normal to it. Fabrication of the device has required the development of bulk micromachining techniques to handle post CMOS fabricated wafers and the patterning of thickly sputtered aluminium in bulk micro machined cavities. CMOS fabrication techniques were used to incorporate diodes onto the quadrapod arms for temperature measurement of the arms. Fine tungsten and silicon tips have also been fabricated to allow tunnelling between the tip and the platform at the centr...

  9. Cosmological Probes for Supersymmetry

    Directory of Open Access Journals (Sweden)

    Maxim Khlopov

    2015-05-01

    Full Text Available The multi-parameter character of supersymmetric dark-matter models implies the combination of their experimental studies with astrophysical and cosmological probes. The physics of the early Universe provides nontrivial effects of non-equilibrium particles and primordial cosmological structures. Primordial black holes (PBHs are a profound signature of such structures that may arise as a cosmological consequence of supersymmetric (SUSY models. SUSY-based mechanisms of baryosynthesis can lead to the possibility of antimatter domains in a baryon asymmetric Universe. In the context of cosmoparticle physics, which studies the fundamental relationship of the micro- and macro-worlds, the development of SUSY illustrates the main principles of this approach, as the physical basis of the modern cosmology provides cross-disciplinary tests in physical and astronomical studies.

  10. Cosmological Probes for Supersymmetry

    CERN Document Server

    Khlopov, Maxim

    2015-01-01

    The multi-parameter character of supersymmetric dark-matter models implies the combination of their experimental studies with astrophysical and cosmological probes. The physics of the early Universe provides nontrivial effects of non-equilibrium particles and primordial cosmological structures. Primordial black holes (PBHs) are a profound signature of such structures that may arise as a cosmological consequence of supersymmetric (SUSY) models. SUSY-based mechanisms of baryosynthesis can lead to the possibility of antimatter domains in a baryon asymmetric Universe. In the context of cosmoparticle physics, which studies the fundamental relationship of the micro- and macro-worlds, the development of SUSY illustrates the main principles of this approach, as the physical basis of the modern cosmology provides cross-disciplinary tests in physical and astronomical studies.

  11. New probe of naturalness.

    Science.gov (United States)

    Craig, Nathaniel; Englert, Christoph; McCullough, Matthew

    2013-09-20

    Any new scalar fields that perturbatively solve the hierarchy problem by stabilizing the Higgs boson mass also generate new contributions to the Higgs boson field-strength renormalization, irrespective of their gauge representation. These new contributions are physical, and in explicit models their magnitude can be inferred from the requirement of quadratic divergence cancellation; hence, they are directly related to the resolution of the hierarchy problem. Upon canonically normalizing the Higgs field, these new contributions lead to modifications of Higgs couplings that are typically great enough that the hierarchy problem and the concept of electroweak naturalness can be probed thoroughly within a precision Higgs boson program. Specifically, at a lepton collider this can be achieved through precision measurements of the Higgs boson associated production cross section. This would lead to indirect constraints on perturbative solutions to the hierarchy problem in the broadest sense, even if the relevant new fields are gauge singlets.

  12. Advanced Langmuir Probe (LP)

    Science.gov (United States)

    Voronka, N. R.; Block, B. P.; Carignan, G. R.

    1991-01-01

    The dynamic response of the MK-2 version of the Langmuir probe amplifier was studied. The settling time of the step response is increased by: (1) stray node-to-ground capacitance at series connections between high value feedback resistors; and (2) input capacitance due to the input cable, FET switches, and input source follower. The stray node-to-ground capacitances can be reduced to tolerable levels by elevating the string of feedback resistors above the printing board. A new feedback network was considered, with promising results. The design uses resistances having much lower nominal values, thereby minimizing the effect of stray capacitances. Faster settling times can be achieved by using an operational amplifier having a higher gain-bandwidth product.

  13. Encapsulation method for atom probe tomography analysis of nanoparticles

    NARCIS (Netherlands)

    Larson, D.J.; Giddings, A.D.; Wub, Y.; Verheijen, M.A.; Prosa, T.J.; Roozeboom, F.; Rice, K.P.; Kessels, W.M.M.; Geiser, B.P.; Kelly, T.F.

    2015-01-01

    Open-space nanomaterials are a widespread class of technologically important materials that are generally incompatible with analysis by atom probe tomography (APT) due to issues with specimen preparation, field evaporation and data reconstruction. The feasibility of encapsulating such non-compact ma

  14. Radiation Belt Storm Probes (RBSP) Payload Safety Introduction Briefing

    Science.gov (United States)

    Loftin, Chuck; Lampert, Dianna; Herrburger, Eric; Smith, Clay; Hill, Stuart; VonMehlem, Judi

    2008-01-01

    Mission of the Geospace Radiation Belt Storm Probes (RBSP) is: Gain s cientific understanding (to the point of predictability) of how populations of relativistic electrons and ions in space form or change in response to changes in solar activity and the solar wind.

  15. 12th Reinventing Space Conference

    CERN Document Server

    2017-01-01

    The 2014 Reinventing Space conference presented a number of questions in the context of a constantly innovating space industry, from addressing the future of global cooperation, investigating the impact of cuts in US government spending on the private space sector, and probing the overall future of the commercial launch sector. Space tourism and new technology promise the revival of interest in space development (the Apollo Era was the first period of intense space activity and growth). The need to create dramatically lower cost, responsive and reliable launch systems and spacecraft has never been more vital. Advances in technology are allowing smaller and cheaper satellites to be orbited - from cubesats to nanosatellites to femtosatellites. Thanks to more efficient new launch possibilities, low cost access to space is becoming ever more achievable. Commercial companies and countries are targeting the industry with new funding. Organised by the British Interplanetary Society, the presentations at this confere...

  16. Measurements of plasma density fluctuations and electric wave fields using spherical electrostatic probes

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, A.I.; Bostroem, R.

    1995-04-01

    Spherical electrostatic probes are in wide use for the measurements of electric fields and plasma density. This report concentrates on the measurements of fluctuations of these quantities rather than background values. Potential problems with the technique include the influence of density fluctuations on electric field measurements and vice versa, effects of varying satellite potential, and non-linear rectification in the probe and satellite sheaths. To study the actual importance of these and other possible effects, we simulate the response of the probe-satellite system to various wave phenomena in the plasma by applying approximate analytical as well as numerical methods. We use a set of non-linear probe equations, based on probe characteristics experimentally obtained in space, and therefore essentially independent of any specific probe theory. This approach is very useful since the probe theory for magnetized plasmas is incomplete. 47 refs.

  17. Antenna Near-Field Probe Station Scanner

    Science.gov (United States)

    Zaman, Afroz J. (Inventor); Lee, Richard Q. (Inventor); Darby, William G. (Inventor); Barr, Philip J. (Inventor); Lambert, Kevin M (Inventor); Miranda, Felix A. (Inventor)

    2011-01-01

    A miniaturized antenna system is characterized non-destructively through the use of a scanner that measures its near-field radiated power performance. When taking measurements, the scanner can be moved linearly along the x, y and z axis, as well as rotationally relative to the antenna. The data obtained from the characterization are processed to determine the far-field properties of the system and to optimize the system. Each antenna is excited using a probe station system while a scanning probe scans the space above the antenna to measure the near field signals. Upon completion of the scan, the near-field patterns are transformed into far-field patterns. Along with taking data, this system also allows for extensive graphing and analysis of both the near-field and far-field data. The details of the probe station as well as the procedures for setting up a test, conducting a test, and analyzing the resulting data are also described.

  18. The Subspace Voyager: Exploring High-Dimensional Data along a Continuum of Salient 3D Subspace.

    Science.gov (United States)

    Wang, Bing; Mueller, Klaus

    2017-02-23

    Analyzing high-dimensional data and finding hidden patterns is a difficult problem and has attracted numerous research efforts. Automated methods can be useful to some extent but bringing the data analyst into the loop via interactive visual tools can help the discovery process tremendously. An inherent problem in this effort is that humans lack the mental capacity to truly understand spaces exceeding three spatial dimensions. To keep within this limitation, we describe a framework that decomposes a high-dimensional data space into a continuum of generalized 3D subspaces. Analysts can then explore these 3D subspaces individually via the familiar trackball interface while using additional facilities to smoothly transition to adjacent subspaces for expanded space comprehension. Since the number of such subspaces suffers from combinatorial explosion, we provide a set of data-driven subspace selection and navigation tools which can guide users to interesting subspaces and views. A subspace trail map allows users to manage the explored subspaces, keep their bearings, and return to interesting subspaces and views. Both trackball and trail map are each embedded into a word cloud of attribute labels which aid in navigation. We demonstrate our system via several use cases in a diverse set of application areas - cluster analysis and refinement, information discovery, and supervised training of classifiers. We also report on a user study that evaluates the usability of the various interactions our system provides.

  19. An Outline of Investigation of Space Medicine Problem and Its Mechanism

    Institute of Scientific and Technical Information of China (English)

    Li Yinghui; Qu Lina; Xiong Jianghui; Wan Yumin; Yuan Ming; Jiang Shizhong

    2004-01-01

    The human exploration of space is one of the great voyages of discovery in human history. For over forty years space exploration, human have gotten more profound knowledge about outer space and life phenomena, ranging from understanding and recognizing space to adapting and utilizing space. With these development, space medicine that aimed at studying effect of space environment on human health and ensuring the safety, health and effective working of human in space exploration, will become increasingly improved and matured.The contents of research will develop from the early phenomena observation of the effect of space environment on human physiology and biochemistry, and the effect definition, to the study of the mechanism of changes of cell, molecule, and gene, from the passive adaptation for space environment to taking the initiative countermeasures, in order to ensure the safety, health and effective working of astronauts during space flight.Space practices in the past forty years have confirmed that a variety of physiological and pathological changes have been found for organism exposed to space flight. These changes include cardiovascular dysfunction, bone loss,muscle atrophy, decline of immune function, endocrine function disorder and space motion sickness. In recent years, more attention has been focused on the study of the mechanism of these changes, especially the effects of space environment on cell, molecule and its gene expression. With the demand of China's manned space engineering task and continuous development, a series of studies on medical problem caused by space environment have been carried out.

  20. A Fast-Response Atmospheric Turbulence (FRAT) Probe with Gas-Sampling Ducts Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aeroprobe proposes to design, construct and test an air-data probe with substantially higher frequency response than currently available. This fast-response...

  1. Miniaturized In Situ Atmospheric Probe Sampling Inlet System for Uranus or Saturn Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Thorleaf Research, Inc. proposes to develop a miniaturized in situ atmospheric probe sampling inlet system for measuring chemical and isotopic composition of the...

  2. Aircraft Based Imaging Probe for the Study of Icing Environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Icing environments are of great concern in commercial and military aviation. An aircraft-based, imaging probe is being proposed for the reliable and accurate...

  3. Miniaturized, Low Power Cryogenic Inlet System with Sampling Probes for Titan Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Thorleaf Research, Inc. proposes to develop a miniature, low power cryogenic inlet system with sampling probes for Titan. This addresses a key technology gap for...

  4. La primera colección de vistas de la Mezquita-Catedral de Córdoba en el Voyage de Laborde (1812

    Directory of Open Access Journals (Sweden)

    García Ortega, Antonio Jesús

    2012-06-01

    Full Text Available The present study deals with the first collection of views of the Mosque-Cathedral of Cordoba, included in Alexandre de Laborde’s huge work, Voyage pittoresque et historique de l’Espagne (volume II, 1812. Despite the fine quality of these original drawings and engravings of Cordoba, the collection has never been examined. Our analysis evaluates its reliability and its documentary contribution to knowledge of this singular edifice in Cordoba and all its architectural transformations. Following an overview of the biographical and historical context of both Laborde and his Voyage, the images are studied in groups according to their points of view: panoramas of the city, the first-known images of the patio, novel interior views, followed by a brief review of plans and details, in part copied from earlier ones.La presente investigación se dedica a la primera colección de vistas de la Mezquita-Catedral de Córdoba, incluidas en la monumental obra de Alexandre de Laborde, Voyage pittoresque et historique de l’Espagne (tomo II, 1812. A pesar de la gran calidad de los grabados y dibujos originales sobre Córdoba, su conjunto no contaba con estudio alguno. Nuestro análisis valora su fiabilidad y su aportación documental al conocimiento del singular edificio cordobés y sus transformaciones arquitectónicas. Tras una aproximación al contexto biográfico e histórico de Laborde y del Voyage, las imágenes se estudian agrupadas según sus puntos de vista: visiones de la ciudad, las primeras vistas conocidas del patio, novedosas vistas interiores, más una breve reseña sobre planos y detalles, en parte copiados de otros anteriores.

  5. Voyager avant 1848 a travers les Principautes Roumaines: les chemins dans la vision des consuls et voyageurs français

    Directory of Open Access Journals (Sweden)

    Violeta-Anca Epure

    2014-07-01

    Full Text Available Les manières de voyager furent différentes dans la période d’avant 1848, mais on suivait le plus souvent les routes terrestres. Les voyageurs et les consuls français, comme le comte d’Hauterive, le général comte de Langeron, le marquis de Salaberry, Louis Allier d’Hauteroche, le comte de Guilleminot, le capitaine Aubert, Alexandre de Moriolles,Charles Frédéric Reinhard et sa femme, Christine, le comte de Lagarde, le diplomate J.M. Tancoigne, le capitaine Thomassin, le comte de Marcellus, J. Jaquin, M. Cochelet, Stanislas Bellanger, Felix Colson, Huber, Fanny de la Rochefoucauld, Duclos, laissèrent dans leurs journaux de voyage ou dans les rapports consulaires de véritables témoignages sur les chemins et leurs voyages à travers les Principautés Roumaines. En général, ceux-ci observèrent l’état déplorable des chemins, tracés le plus souvent au hasard, la difficulté de voyager en ces parages-là, l’organisation précaire des stations de poste, l’insécurité des routes, mais aussi le caractère loyal des habitants. Habitués avec les réalités de l’ouest du continent européen, plusieurs de ceux-ci croyaient qu’il voyageraient comme en France, mais leurs espoirs prouvèrent rapidement illusoires.

  6. Dispersive Magnetosonic Waves and Turbulence in the Heliosheath: Multi-Fluid MHD Reconstruction of Voyager 2 Observations

    Science.gov (United States)

    Zieger, B.; Opher, M.; Toth, G.

    2016-12-01

    Recently we demonstrated that our three-fluid MHD model of the solar wind plasma (where cold thermal solar wind ions, hot pickup ions, and electrons are treated as separate fluids) is able to reconstruct the microstructure of the termination shock observed by Voyager 2 [Zieger et al., 2015]. We constrained the unknown pickup ion abundance and temperature and confirmed the presence of a hot electron population at the termination shock, which has been predicted by a number of previous theoretical studies [e.g. Chasei and Fahr, 2014; Fahr et al., 2014]. We showed that a significant part of the upstream hydrodynamic energy is transferred to the heating of pickup ions and "massless" electrons. As shown in Zieger et al., [2015], three-fluid MHD theory predicts two fast magnetosonic modes, a low-frequency fast mode or solar wind ion (SW) mode and a high-frequency fast mode or pickup ion (PUI) mode. The coupling of the two ion populations results in a quasi-stationary nonlinear mode or oscilliton, which appears as a trailing wave train downstream of the termination shock. In single-fluid plasma, dispersive effects appear on the scale of the Debye length. However, in a non-equilibrium plasma like the solar wind, where solar wind ions and PUIs have different temperatures, dispersive effects become important on fluid scales [see Zieger et al., 2015]. Here we show that the dispersive effects of fast magnetosonic waves are expected on the scale of astronomical units (AU), and dispersion plays an important role producing compressional turbulence in the heliosheath. The trailing wave train of the termination shock (the SW-mode oscilliton) does not extend to infinity. Downstream propagating PUI-mode waves grow until they steepen into PUI shocklets and overturn starting to propagate backward. The upstream propagating PUI-mode waves result in fast magnetosonic turbulence and limit the downstream extension of the oscilliton. The overturning distance of the PUI-mode, where these waves

  7. Synthesis of Photoactivatable Phospholipidic Probes

    Institute of Scientific and Technical Information of China (English)

    Qing PENG; Fan Qi QU; Yi XIA; Jie Hua ZHOU; Qiong You WU; Ling PENG

    2005-01-01

    We synthesized and characterized photoactivatable phospholipidic probes 1-3. These probes have the perfluorinated aryl azide function at the polar head of phospholipid. They are stable in dark and become highly reactive upon photoirradiation. The preliminary results suggest that they are promising tools to study the topology of membrane proteins and protein-lipid interactions using photolabeling approach.

  8. Non-inductive current probe

    DEFF Research Database (Denmark)

    Bak, Christen Kjeldahl

    1977-01-01

    The current probe described is a low-cost, shunt resistor for monitoring current pulses in e.g., pulsed lasers. Rise time is......The current probe described is a low-cost, shunt resistor for monitoring current pulses in e.g., pulsed lasers. Rise time is...

  9. Encyclopédies du voyage et Cartoville. Pourquoi deux guides Gallimard consacrés à Lausanne ? Encyclopédies du voyage and Cartoville. Why two Gallimard guides of Lausanne?

    Directory of Open Access Journals (Sweden)

    Ariane Devanthéry

    2009-10-01

    Full Text Available Sur la route des voyageurs depuis plus de trois siècles et jouissant d’une localisation remarquable, la ville de Lausanne est une entrée courante des guides de voyage. Récemment, on a même vu les guides qui lui sont dédiés se multiplier de manière étonnante. Si l’on comprend clairement l’intérêt que les différentes maisons d’édition y trouvent, ainsi que les particularités de chacune de leurs réalisations, on peut toutefois s’interroger sur l’avantage que peut avoir un même éditeur à faire paraître deux guides distincts sur le même lieu. Et si la différence tenait justement au paysage ?Lausanne, part of travellers’ repertoire for over three centuries, enjoys a unique location and is frequently mentioned in travel guides. Guides devoted to it have mushroomed in the past few years. It is easy to understand the interest of Publishing Houses, just as the particular topics explored in their individual guides. Yet one still wonders what benefit a publisher may draw by issuing two distinct guides of the very same place. What if the difference lay precisely in the landscape?

  10. Cobra Probes Containing Replaceable Thermocouples

    Science.gov (United States)

    Jones, John; Redding, Adam

    2007-01-01

    A modification of the basic design of cobra probes provides for relatively easy replacement of broken thermocouples. Cobra probes are standard tube-type pressure probes that may also contain thermocouples and that are routinely used in wind tunnels and aeronautical hardware. They are so named because in side views, they resemble a cobra poised to attack. Heretofore, there has been no easy way to replace a broken thermocouple in a cobra probe: instead, it has been necessary to break the probe apart and then rebuild it, typically at a cost between $2,000 and $4,000 (2004 prices). The modified design makes it possible to replace the thermocouple, in minimal time and at relatively low cost, by inserting new thermocouple wire in a tube.

  11. Nanobits: customizable scanning probe tips

    DEFF Research Database (Denmark)

    Kumar, Rajendra; Shaik, Hassan Uddin; Sardan Sukas, Özlem

    2009-01-01

    silicon processing. Using a microgripper they were detached from an array and fixed to a standard pyramidal AFM probe or alternatively inserted into a tipless cantilever equipped with a narrow slit. The nanobit-enhanced probes were used for imaging of deep trenches, without visible deformation, wear......We present here a proof-of-principle study of scanning probe tips defined by planar nanolithography and integrated with AFM probes using nanomanipulation. The so-called 'nanobits' are 2-4 mu m long and 120-150 nm thin flakes of Si3N4 or SiO2, fabricated by electron beam lithography and standard...... or dislocation of the tips of the nanobit after several scans. This approach allows an unprecedented freedom in adapting the shape and size of scanning probe tips to the surface topology or to the specific application....

  12. Wearable probes for service design

    DEFF Research Database (Denmark)

    Mullane, Aaron; Laaksolahti, Jarmo Matti; Svanæs, Dag

    2014-01-01

    by service employees in reflecting on the delivery of a service. In this paper, we present the ‘wearable probe’, a probe concept that captures sensor data without distracting service employees. Data captured by the probe can be used by the service employees to reflect and co-reflect on the service journey......Probes are used as a design method in user-centred design to allow end-users to inform design by collecting data from their lives. Probes are potentially useful in service innovation, but current probing methods require users to interrupt their activity and are consequently not ideal for use......, helping to identify opportunities for service evolution and innovation....

  13. Electrophoresis-mass spectrometry probe

    Science.gov (United States)

    Andresen, Brian D.; Fought, Eric R.

    1987-01-01

    The invention involves a new technique for the separation of complex mixtures of chemicals, which utilizes a unique interface probe for conventional mass spectrometers which allows the electrophoretically separated compounds to be analyzed in real-time by a mass spectrometer. This new chemical analysis interface, which couples electrophoresis with mass spectrometry, allows complex mixtures to be analyzed very rapidly, with much greater specificity, and with greater sensitivity. The interface or probe provides a means whereby large and/or polar molecules in complex mixtures to be completely characterized. The preferred embodiment of the probe utilizes a double capillary tip which allows the probe tip to be continually wetted by the buffer, which provides for increased heat dissipation, and results in a continually operating interface which is more durable and electronically stable than the illustrated single capillary tip probe interface.

  14. Mobile Probes in Mobile Learning

    DEFF Research Database (Denmark)

    Ørngreen, Rikke; Blomhøj, Ulla; Duvaa, Uffe

    as an agent for acquiring empirical data (as the situation in hitherto mobile probe settings) but was also the technological medium for which data should say something about (mobile learning). Consequently, not only the content of the data but also the ways in which data was delivered and handled, provided......In this paper experiences from using mobile probes in educational design of a mobile learning application is presented. The probing process stems from the cultural probe method, and was influenced by qualitative interview and inquiry approaches. In the project, the mobile phone was not only acting...... a valuable dimension for investigating mobile use. The data was collected at the same time as design activities took place and the collective data was analysed based on user experience goals and cognitive processes from interaction design and mobile learning. The mobile probe increased the knowledge base...

  15. The Convected Kappa Distribution Function at Jupiter: Details from the Voyager and Galileo Missions and a Comparison to Cassini Saturn Measurements

    Science.gov (United States)

    Kane, M.; Mitchell, D. G.; Mauk, B.; Carbary, J. F.; Hill, M. E.; Dialynas, K.; Krimigis, S. M.

    2016-12-01

    The Voyager and Galileo Missions allowed detailed measurements of 20 keV-2 MeV hot ion distributions in Jupiter's magnetosphere and beyond using the LECP detector on Voyager and EPD on Galileo. The normalized convected kappa distribution function, with isotropy assumed in the plasma convection frame, has well fit hot ion observed fluxes and thus has produced meaningful and ordered physical plasma parameters including the vector bulk velocity, the characteristic energy (temperature) of the distribution, and the high energy spectral index. The kappa model produces temperatures that indicate expansion and adiabatic cooling of hot ions in the nightside, but not in the dayside. Further, there are significant variations in the plasma parameters with time and local time. There is also a boundary layer present near but within the dawn magnetopause where distribution functions were generated from data analysis of the very distant Voyager 2 crossing of this region. Here the flow is apparently entrained into the magnetosheath flow, but temperatures are hot and consistent with rapid transport of plasma from regions of the magnetosphere closer to Jupiter. These observations have led to the proposal of an empirical model of the general convection pattern at Jupiter. Remarkably, application of the convected kappa distribution model to Saturn using Cassini INCA and CHEMS measurements produces a convection pattern and kappa distribution temperature profiles that are remarkably similar when scaled by the sub-solar magnetopause distance and radial size of the planets.

  16. Four-point probe resistance measurements using PtIr-coated carbon nanotube tips.

    Science.gov (United States)

    Yoshimoto, Shinya; Murata, Yuya; Kubo, Keisuke; Tomita, Kazuhiro; Motoyoshi, Kenji; Kimura, Takehiko; Okino, Hiroyuki; Hobara, Rei; Matsuda, Iwao; Honda, Shin-Ichi; Katayama, Mitsuhiro; Hasegawa, Shuji

    2007-04-01

    We performed four-terminal conductivity measurements on a CoSi2 nanowire (NW) at room temperature by using PtIr-coated carbon nanotube (CNT) tips in a four-tip scanning tunneling microscope. The physical stability and high aspect ratio of the CNT tips made it possible to reduce the probe spacing down to ca. 30 nm. The probe-spacing dependence of resistance showed diffusive transport even at 30 nm and no current leakage to the Si substrate.

  17. SPRITE - The Saturn PRobe Interior and aTmosphere Explorer Mission.

    Science.gov (United States)

    Atkinson, D. H.; Simon, A. A.; Banfield, D. J.; Atreya, S. K.; Blacksberg, J.; Brinckerhoff, W. B.; Colaprete, A.; Coustenis, A.; Danner, R. M.; Fletcher, L. N.; Guillot, T.; Hofstadter, M. D.; Keithly, D.; Lobbia, M. A.; Lunine, J. I.; Mahaffy, P. R.; Marley, M. S.; Mousis, O.; Spilker, T. R.; Trainer, M. G.; Webster, C. R.; Youmans, T. A.

    2016-12-01

    The 2013-2022 Planetary Science Decadal Survey (PSDS) Vision and Voyages Planetary identified a Saturn Probe mission as a high priority mission target for the NASA New Frontiers program. Fundamental measurements of noble gas abundances and isotope ratios of hydrogen, carbon, oxygen, and nitrogen, as well as the interior structure of Saturn are needed to help constrain Solar System formation models and to provide an improved context for understanding exoplanet systems. The SPRITE mission would fulfill the PSDS scientific goals for in situ exploration of Saturn, and would additionally provide ground truth for remote sensing that would improve the understanding of the composition and interior structure of Saturn and, by proxy, extrasolar giant planets. In Situ measurements are the only means to address many key questions regarding the structure and composition of Saturn's atmosphere including the abundance of noble gases and key isotopes, the abundance of helium needed to understand the formation history and thermal evolution of Saturn, and the abundance of water in the deep atmosphere, a key diagnostic of Saturn's formation since it is thought that the heavy elements were delivered by water-bearing planetesimals. The SPRITE atmospheric entry probe mission including remote sensing from a carrier-relay spacecraft would measure many of these key atmospheric constituents as well as the atmospheric structure of Saturn including temperature, pressure and wind speeds along the probe descent path thereby providing interior science not accessible to remote sensing measurements. Additionally, the SPRITE carrier-relay spacecraft would make remote sensing measurements to support probe measurements in the upper troposphere of Saturn.

  18. Designing a probe beam and an ultraviolet holographic microinterferometer for plasma probing.

    Science.gov (United States)

    Pierce, E L

    1980-03-15

    The requirements and techniques for time- and space-resolved picosecond probing of laser-produced plasmas are reviewed. The design and limitations of a holographic microinterferometer are discussed, and optical pulse techniques are presented. This technique can provide significant data for understanding the absorption of energy within laser-produced plasmas. The primary requirements are to measure the electron densities in the 10(20)-10(21)-e/cc range, with density contour velocities of 10(6) to 10(7) cm/sec and spatial resolution of 1 microm or better. For these velocities one requires a probe pulse duration of 3-30 psec, an UV wavelength as short as feasible, and large numerical aperture optics corrected for spherical aberration. Interferograms of laser-produced plasmas obtained at 2660 A with a combined resolution of 1 microm and 15 psec are presented.

  19. Steerable Doppler transducer probes

    Energy Technology Data Exchange (ETDEWEB)

    Fidel, H.F.; Greenwood, D.L.

    1986-07-22

    An ultrasonic diagnostic probe is described which is capable of performing ultrasonic imaging and Doppler measurement consisting of: a hollow case having an acoustic window which passes ultrasonic energy and including chamber means for containing fluid located within the hollow case and adjacent to a portion of the acoustic window; imaging transducer means, located in the hollow case and outside the fluid chamber means, and oriented to direct ultrasonic energy through the acoustic window toward an area which is to be imaged; Doppler transducer means, located in the hollow case within the fluid chamber means, and movably oriented to direct Doppler signals through the acoustic window toward the imaged area; means located within the fluid chamber means and externally controlled for controllably moving the Doppler transducer means to select one of a plurality of axes in the imaged area along which the Doppler signals are to be directed; and means, located external to the fluid chamber means and responsive to the means for moving, for providing an indication signal for identifying the selected axis.

  20. Transient Astrophysics Probe

    Science.gov (United States)

    Camp, Jordan

    2017-08-01

    Transient Astrophysics Probe (TAP), selected by NASA for a funded Concept Study, is a wide-field high-energy transient mission proposed for flight starting in the late 2020s. TAP’s main science goals, called out as Frontier Discovery areas in the 2010 Decadal Survey, are time-domain astrophysics and counterparts of gravitational wave (GW) detections. The mission instruments include unique imaging soft X-ray optics that allow ~500 deg2 FoV in each of four separate modules; a high sensitivity, 1 deg2 FoV soft X-ray telescope based on single crystal silicon optics; a passively cooled, 1 deg2 FoV Infrared telescope with bandpass 0.6-3 micron; and a set of ~8 small NaI gamma-ray detectors. TAP will observe many events per year of X-ray transients related to compact objects, including tidal disruptions of stars, supernova shock breakouts, neutron star bursts and superbursts, and high redshift Gamma-Ray Bursts. Perhaps most exciting is TAP’s capability to observe X-ray and IR counterparts of GWs involving stellar mass black holes detected by LIGO/Virgo, and possibly X-ray counterparts of GWs from supermassive black holes, detected by LISA and Pulsar Timing Arrays.

  1. Space Station

    Science.gov (United States)

    Anderton, D. A.

    1985-01-01

    The official start of a bold new space program, essential to maintain the United States' leadership in space was signaled by a Presidential directive to move aggressively again into space by proceeding with the development of a space station. Development concepts for a permanently manned space station are discussed. Reasons for establishing an inhabited space station are given. Cost estimates and timetables are also cited.

  2. Vamos ao Brasil com Jules Verne?: processos editoriais e civilização nas Voyages Extraordinaires

    Directory of Open Access Journals (Sweden)

    Andréa Borges Leão

    2012-12-01

    Full Text Available No século XIX, uma rede de conhecimentos sobre as diferenças culturais dos povos americanos marcou a edição destinada à instrução e diversão da juventude francesa. Uma das 62 Voyages Extraordinaires de Jules Verne, publicadas por Pierre-Jules Hetzel, é ambientada entre o Peru e o Brasil: La Jangada, huit cents lieues sur l'Amazone (1881. Na produção de literatura juvenil que se desenvolve e expande no comércio transatlântico da livraria francesa, sobressai uma psicogênese do Brasil. Por esse ângulo, a via de análise aberta pelo sociólogo Norbert Elias ajudou a enfrentar o problema das emoções humanas, no romance de viagem, e a conceituar a atividade mimética no livro de ciência e recreação.

  3. Récit et éthique dans l’écriture du voyage de Camilo José Cela

    Directory of Open Access Journals (Sweden)

    Carmen Dubois

    2005-04-01

    Full Text Available Au delà de la simple narration d’un parcours spatial, les récits de voyage de Camilo José Cela ont une forte dimension éthique. Le vagabondage célien est la manifestation d’une certaine vision du monde et de l’homme construite autour de trois notions clés: renoncement, vitalité et utopie. Le voyageur se veut ainsi à l’image de cet idéal célien ; sa vie est réglée par une déontologie précise : le détachement, la solitude, la communion avec la nature, l’éloignement de la ville et l’attachement au monde rural sont les plus manifestes. En dernière instance, le vagabondage, éthique exigeante et réservée à quelque êtres d’exception, est la voie qui mène à la liberté et au bonheur.

  4. Transition from the Sector Zone to the Unipolar Zone in the Heliosheath: Voyager 2 Magnetic Field Observations

    Science.gov (United States)

    Burlaga, L. F.; Ness, N. F.

    2011-01-01

    The magnetic polarity pattern observed by Voyager 2 (V2) evolved with time from a nearly equal mixture of positive and negative polarity sectors in the sector zone from 2007.00 to 2007.67 to nearly uniform positive polarity (magnetic fields directed away from the Sun) in the unipolar zone from 2009.6 to 2010.3. This change was caused by the decreasing latitudinal extent of the sector zone, when the minimum extent of the heliospheric current sheet moved northward toward the solar equator as the solar activity associated with solar cycle 23 decreased a minimum in 2010. In the heliosheath, the distribution of daily averages of the magnetic field strength B was lognormal in the sector zone from 2008.83 to 2009.57 and Gaussian in the unipolar zone from 2009.57 to 2010.27. The distribution of daily increments of B was a Tsallis distribution (q-Gaussian distribution) with q = 1.66 +/- 0.010 in the sector zone and . Gaussian (q = 1.01+/-0.29) in the unipolar zone. The unipolar region appears to be in a relatively undisturbed equilibrium state.

  5. Sectors and Large-Scale Magnetic Field Strength Fluctuations in the Heliosheath Near 110 AU: Voyager 1,2009

    Science.gov (United States)

    Burlaga, L. F.; Ness, N. F.

    2010-01-01

    This paper describes observations of daily averages of the magnetic field strength B and the magnetic polarity measured by Voyager 1 (V1) in the heliosheath during 2009 between 108.5 and 112.1 AU and at heliographic latitude 34. . 4. A negative magnetic polarity sector was observed during 2009 DOY 43.255. A positive polarity sector was observed during 2009 DOY 256.365. We offer the hypothesis that the existence of the two sectors is the result of the displacement of the wavy heliospheric current sheet to the position of V1 as a result of northward flow in the heliosheath. The large size of the sectors is caused by the slow radial motion of the flow observed by V1 in the heliosheath. The distribution of B during 2009 was lognormal, in contrast to the Gaussian distributions observed by V1 in the heliosheath prior to 2009. The large-scale fluctuations of B, described by the distribution of increments of daily averages of B, have a Tsallis distribution with q = 1.6. The large-scale fluctuations of B observed by V1 during 2009 have a multifractal spectrum with the same parameters that V1 observed during 2005 close to the termination shock at 94 AU. These results suggest that the large-scale magnetic fluctuations of B are in a metastable equilibrium state in the heliosheath between 94 AU and 112.1 AU.

  6. Bringing Space Science into the Kindergarten Classroom

    Science.gov (United States)

    Bonett, D. M.; Little, K. E.

    2000-01-01

    With the advent of probes to Mars and the construction of the ISS, it is not presumptuous to introduce 5-year-olds to space science. A variety of projects have been implemented to integrate space science into the kindergarten curriculum.

  7. The LC resonance probe for determining local plasma density

    Energy Technology Data Exchange (ETDEWEB)

    Boris, D R; Fernsler, R F; Walton, S G, E-mail: david.boris.ctr@nrl.navy.mi [Naval Research Laboratory, Charge Particle Physics Branch-Code 6752, Plasma Physics Division, 4555 Overlook Ave. SW, Washington, DC 20375 (United States)

    2011-04-15

    We present a novel plasma diagnostic for measuring local plasma density in reactive-gas plasmas, and depositing plasmas. The diagnostic uses a network analyzer to measure the LC resonance (LCR) frequency of a parallel plate capacitor with inductive leads. The location of the LCR ({omega}{sub R}) in frequency space is then used as a measure of the plasma dielectric constant bold varepsilon{sub p} between the plates. By properly constructing the LCR probe, {omega}{sub R} can be tuned such that {omega}{sub R} >> {omega}{sub ce}, where {omega}{sub ce} is the electron-cyclotron frequency. Thus, the probe can be used in plasmas with varying degrees of magnetization while avoiding complications introduced to bold varepsilon{sub p} when {omega} is comparable to {omega}{sub ce}. Density measurements from the LCR probe are compared with Langmuir probe measurements in an electron-beam generated plasma in which density varied from 10{sup 9} to 10{sup 11} cm{sup -3}. An axial magnetic field, typically used to confine the electron beam, was varied between 0 to 300 G. The LCR probe showed good agreement with a Langmuir probe across the entire range of magnetic fields.

  8. The Galileo Probe: How it Has Changed Our Understanding of Jupiter

    Science.gov (United States)

    Young, Richard E.

    2003-01-01

    The Galileo Mission to Jupiter, which arrived in December of 1995, provided the first study by an orbiter, and the first in-situ sampling via an entry probe, of an outer planet atmosphere. The rationale for an entry probe is that, even from an orbiter, remote sensing of the jovian atmosphere could not adequately retrieve the information desired. This paper provides a current summary of the most significant aspects of the data returned from the Galileo entry probe. As a result of the probe measurements, there has been a reassessment of our understanding of outer planet formation and evolution of the solar system. The primary scientific objective of the Galileo probe was to determine the composition of the jovian atmosphere, which from remote sensing remained either very uncertain, or completely unknown, with respect to several key elements. The probe found that the global He mass fraction is. significantly above the value reported from the Voyager Jupiter flybys but is slightly below the protosolar value, implying that there has been some settling of He to the deep jovian interior. The probe He measurements have also led to a reevaluation of the Voyager He mass fraction for Saturn, which is now determined to be much closer to that of Jupiter. The elements C, N, S, Ar, Kr, Xe were all found to have global abundances approximately 3 times their respective solar abundances. This result has raised a number of fundamental issues with regard to properties of planetesimals and the solar nebula at the time of giant planet formation. Ne, on the other hand, was found to be highly depleted, probably as the result of it being carried along with helium as helium settles towards the deep interior. The global abundance of O was not obtained by the probe because of the influence of local processes at the probe entry site (PES), processes which depleted condensible species, in this case H2O, well below condensation levels. Other condensible species, namely NH3 and H2S, were

  9. Probing the Earth from space - The Aristoteles mission

    Science.gov (United States)

    Schuyer, M.; Silvestrin, P.; Aguirre, M.

    1992-11-01

    The Aristoteles mission has been under study by the Agency since 1987. Its aim is to provide global models of the Earth's gravitational and magnetic fields with high spatial resolution and accuracy. Following earlier discussions, in 1990 NASA confirmed its intention to participate in the mission with the provision of a dedicated launch and of additional instruments. This has made it possible to enhance the scientific and application-orientated value of the mission and to optimize the spacecraft design. This article reviews the new joint ESA-NASA Aristoteles mission, as well as the status of the system definition and of the associated technological pre-development activities.

  10. Projecting the graviton to probe higher or lower dimensions

    CERN Document Server

    Mazumdar, Anupam

    2015-01-01

    In this paper, we will discuss how in Einstein's theory a graviton can be enforced to probe fewer space-time dimensions in the deep ultraviolet (UV) as compared to far infrared (IR), and vice-versa. In particular, from a $D$ dimensional gravitational action in the IR we can project the $D$ dimensional graviton to probe only $2\\leq N\\leq D-1$ dimensions in the deep UV. Such projections of a graviton propagator can be thought of as an alternative to compactification. We will briefly explain the physical interpretation and consequences of such a dimensional transmutation.

  11. Hard jet probes in terms of colorless QCD dipoles

    CERN Document Server

    Peschanski, R

    2000-01-01

    the forward jet playing the role of a hard probe is analyzed in terms of QCD dipole (color-singlet q\\bar q) configurations in the transverse position space. There are sizable differences with the analogous q\\bar q configurations of a hard photon which may lead to significant phenomenological consequences on the analysis of hard processes using a forward jet probe, e.g. at the Tevatron. A geometrical interpretation of the resulting distribution in terms of black disk diffraction is proposed.

  12. A subcutaneous Raman needle probe.

    Science.gov (United States)

    Day, John C C; Stone, Nicholas

    2013-03-01

    Raman spectroscopy is a powerful tool for studying the biochemical composition of tissues and cells in the human body. We describe the initial results of a feasibility study to design and build a miniature, fiber optic probe incorporated into a standard hypodermic needle. This probe is intended for use in optical biopsies of solid tissues to provide valuable information of disease type, such as in the lymphatic system, breast, or prostate, or of such tissue types as muscle, fat, or spinal, when identifying a critical injection site. The optical design and fabrication of this probe is described, and example spectra of various ex vivo samples are shown.

  13. Subminiature Hot-Wire Probes

    Science.gov (United States)

    Westphal, R. V.; Lemos, F. R.; Ligrani, P. M.

    1989-01-01

    Class of improved subminiature hot-wire flow-measuring probes developed. Smaller sizes yield improved resolution in measurements of practical aerodynamic flows. Probe made in one-wire, two-perpendicular-wire, and three-perpendicular-wire version for measurement of one, two, or all three components of flow. Oriented and positioned on micromanipulator stage and viewed under microscope during fabrication. Tested by taking measurements in constant-pressure turbulent boundary layer. New probes give improved measurements of turbulence quantities near surfaces and anisotropies of flows strongly influence relative errors caused by phenomena related to spatial resolution.

  14. Optic probe for semiconductor characterization

    Science.gov (United States)

    Sopori, Bhushan L.; Hambarian, Artak

    2008-09-02

    Described herein is an optical probe (120) for use in characterizing surface defects in wafers, such as semiconductor wafers. The optical probe (120) detects laser light reflected from the surface (124) of the wafer (106) within various ranges of angles. Characteristics of defects in the surface (124) of the wafer (106) are determined based on the amount of reflected laser light detected in each of the ranges of angles. Additionally, a wafer characterization system (100) is described that includes the described optical probe (120).

  15. The State-of-the-art in Space Robotics

    Science.gov (United States)

    da Fonseca, Ijar M.; Pontuschka, Maurício N.

    2015-10-01

    This paper deals with the space robotics and associate space applications. An overview of the space era and the robotic space probes is presented to contextualize the space robotics in the space exploration scenario. Concepts, classification and key-questions associated with robotics for space applications are presented and discussed. Safety-critical aspects of the space robotics are discussed as well the human limitation to operate in the hostile space environment and long time duration missions. The paper also focuses on the state-of-the- art of robotics for the International Space Station EVA operations, for the planetary exploration such as the ongoing Mars exploration, Hayabusa rendezvous and landing in asteroids and the robotic probe Rosetta landed in a comet recently. The paper also includes a discussion of the applications of new concepts like the robonauts, the space tugs applications and robots for future planetary exploration.

  16. Voyage to Troy: A mission concept for the exploration of the Trojan asteroids

    Science.gov (United States)

    Saikia, S.; Das, A.; Laipert, F.; Dapkus, C.; Kendall, J.; Bowling, T.; Steckloff, J.; Holbert, S.; Graves, K.; Anthony, T.; Bobick, R.; Huang, Y.; Stuart, J.; Longuski, J.; Minton, D.

    2014-07-01

    The Trojan asteroids, located at Jupiter's L4 and L5 Lagrange points, are a potential source of insights into long-standing questions on the origin and early history of the Solar System. The 2013 Planetary Science Decadal Survey recommends a Trojan Tour and Rendezvous mission as high-priority among medium-class missions. A dedicated mission to the Trojan asteroids could confirm or refute multiple theories to correctly explain the Trojan asteroids' current location, characteristics, and behavior. In-depth and conclusive evidence for the Trojan asteroids' internal and external make-up as well as dynamical behavior hav been challenging due to limitations of ground- and space-based observations. Notwithstanding these limitations, it has been inferred that there are two distinct sub- populations that are distinguishable in visible and near-infrared spectra (redder and less red) within the swarms. These spectral groupings have not yet been conclusively linked to physical characteristics (e.g. size) or other observed parameters (e.g. albedo) of the primordial bodies. NASA's Jet Propulsion Laboratory's concept studies for Decadal Survey evaluated three concepts for missions to Trojan asteroids: each utilizing chemical- solar-electric, and radioisotope-electric for propulsion. Both Solar and Advanced Stirling Radioisotope Generators were considered for power [2]. We present a new conceptual mission to explore the Trojan asteroids that achieves the science goals prioritized in the 2013 Planetary Science Decadal Survey. The proposed mission aims to study both a redder and less red asteroid for the surface mineralogical and elemental composition, state of surface regolith, evidence and consequences of external modification processes such as collisional evolution, space weathering, and irradiation. Some potential targets in the L4 Greek camp currently under consideration for this mission include Achilles, Hektor and Agamemnon (redder) and Eurybates, Deipylos and Kalchas (less

  17. Micro-four-point probes in a UHV scanning electron microscope for in-situ surface-conductivity measurements

    DEFF Research Database (Denmark)

    Shiraki, I.; Nagao, T.; Hasegawa, S.;

    2000-01-01

    For in-situ measurements of surface conductivity in ultrahigh vacuum (UHV), we have installed micro-four-point probes (probe spacings down to 4 mum) in a UHV scanning electron microscope (SEM) combined with scanning reflection-high-energy electron diffraction (RHEED). With the aid of piezoactuators...... for precise positioning of the probes, local conductivity of selected surface domains of well-defined superstructures could be measured during SEM and RHEED observations. It was found that the surface sensitivity of the conductivity measurements was enhanced by reducing the probe spacing, enabling...

  18. Messengers from outer space

    Energy Technology Data Exchange (ETDEWEB)

    Jockers, K.

    1981-12-11

    In connection with the planned ESA space probe to Halley's Comet, a survey of our current knowledge of comets, and of open questions concerning them. The coma and the plasma and dust tail arise from the nucleus of the comet. Comets contain large amounts of water ice, and are surrounded by a gigantic cloud of hydrogen that is not visible to ground observation. The plasma tail arises by interaction with the solar wind. The cometary dust probably contains the most significant information on the origins of the solar system. Comets may contain prebiotic complex molecules.

  19. Probing quantum commutators

    CERN Document Server

    Rossi, Matteo A C; Paris, Matteo G A

    2016-01-01

    Quantum gravity theories predict a minimal length at the order of magnitude of the Planck length, under which the concepts of space and time lose every physical meaning. In quantum mechanics, the insurgence of such minimal length can be described by introducing a modified position-momentum commutator, which in turn yields a generalized uncertainty principle, where the uncertainty on the position measurement has a lower bound. The value of the minimal length is not predicted by theories and must be evaluated experimentally. In this paper, we address the quantum bound to estimability of the minimal uncertainty length by performing measurements on a harmonic oscillator, which is analytically solvable in the deformed algebra of the Hilbert subspace.

  20. DNA probe for lactobacillus delbrueckii

    Energy Technology Data Exchange (ETDEWEB)

    Delley, M.; Mollet, B.; Hottinger, H. (Nestle Research Centre, Lausanne (Switzerland))

    1990-06-01

    From a genomic DNA library of Lactobacillus delbrueckii subsp. bulgaricus, a clone was isolated which complements a leucine auxotrophy of an Escherichia coli strain (GE891). Subsequent analysis of the clone indicated that it could serve as a specific DNA probe. Dot-blot hybridizations with over 40 different Lactobacillus strains showed that this clone specifically recognized L. delbrueckii subsp. delbrueckii, bulgaricus, and lactis. The sensitivity of the method was tested by using an {alpha}-{sup 32}P-labeled probe.