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Sample records for planet search program

  1. The Carnegie Astrometric Planet Search Program

    CERN Document Server

    Boss, Alan P; Anglada-Escude, Guillem; Thompson, Ian B; Burley, Gregory; Birk, Christoph; Pravdo, Steven H; Shaklan, Stuart B; Gatewood, George D; Majewski, Steven R; Patterson, Richard J

    2009-01-01

    We are undertaking an astrometric search for gas giant planets and brown dwarfs orbiting nearby low mass dwarf stars with the 2.5-m du Pont telescope at the Las Campanas Observatory in Chile. We have built two specialized astrometric cameras, the Carnegie Astrometric Planet Search Cameras (CAPSCam-S and CAPSCam-N), using two Teledyne Hawaii-2RG HyViSI arrays, with the cameras' design having been optimized for high accuracy astrometry of M dwarf stars. We describe two independent CAPSCam data reduction approaches and present a detailed analysis of the observations to date of one of our target stars, NLTT 48256. Observations of NLTT 48256 taken since July 2007 with CAPSCam-S imply that astrometric accuracies of around 0.3 milliarcsec per hour are achievable, sufficient to detect a Jupiter-mass companion orbiting 1 AU from a late M dwarf 10 pc away with a signal-to-noise ratio of about 4. We plan to follow about 100 nearby (primarily within about 10 pc) low mass stars, principally late M, L, and T dwarfs, for 10...

  2. Korean-Japanese Planet Search Program: Substellar Companions around Intermediate-Mass Giants

    CERN Document Server

    Omiya, Masashi; Izumiura, Hideyuki; Lee, Byeong-Cheol; Sato, Bun'ei; Kim, Kang-Min; Yoon, Tae Seog; Kambe, Eiji; Yoshida, Michitoshi; Masuda, Seiji; Toyota, Eri; Urakawa, Seitaro; Takada-Hidai, Masahide

    2011-01-01

    A Korean-Japanese planet search program has been carried out using the 1.8m telescope at Bohyunsan Optical Astronomy Observatory (BOAO) in Korea, and the 1.88m telescope at Okayama Astrophysical Observatory (OAO) in Japan to search for planets around intermediate-mass giant stars. The program aims to show the properties of planetary systems around such stars by precise Doppler survey of about 190 G or K type giants together with collaborative surveys of the East-Asian Planet Search Network. So far, we detected two substellar companions around massive intermediate-mass giants in the Korean-Japanese planet search program. One is a brown dwarf-mass companion with 37.6 $M_{\\mathrm{J}}$ orbiting a giant HD 119445 with 3.9 $M_{\\odot}$, which is the most massive brown dwarf companion among those found around intermediate-mass giants. The other is a planetary companion with 1.8 $M_{\\mathrm{J}}$ orbiting a giant star with 2.4 $M_{\\odot}$, which is the lowest-mass planetary companion among those detected around giant s...

  3. The Search for Planet Nine

    Science.gov (United States)

    Brown, Michael E.; Batygin, Konstantin

    2016-10-01

    We use an extensive suite of numerical simulations to constrain the mass and orbit of Planet Nine, and we use these constraints to begin the search for this newly proposed planet in new and in archival data. Here, we compare our simulations to the observed population of aligned eccentric high semimajor axis Kuiper belt objects and determine which simulation parameters are statistically compatible with the observations. We find that only a narrow range of orbital elements can reproduce the observations. In particular, the combination of semimajor axis, eccentricity, and mass of Planet Nine strongly dictates the semimajor axis range of the orbital confinement of the distant eccentric Kuiper belt objects. Allowed orbits, which confine Kuiper belt objects with semimajor axis beyond 380 AU, have perihelia roughly between 150 and 350 AU, semimajor axes between 380 and 980 AU, and masses between 5 and 20 Earth masses. Orbitally confined objects also generally have orbital planes similar to that of the planet, suggesting that the planet is inclined approximately 30 degrees to the ecliptic. We compare the allowed orbital positions and estimated brightness of Planet Nine to previous and ongoing surveys which would be sensitive to the planet's detection and use these surveys to rule out approximately two-thirds of the planet's orbit. Planet Nine is likely near aphelion with an approximate brightness of 22hours. We discuss the state of our current and archival searches for this newly predicted planet.

  4. Spectroscopic characterization of a sample of metal-poor solar-type stars from the HARPS planet search program

    CERN Document Server

    Sousa, Sérgio G; Israelian, Garik; Lovis, C; Mayor, Michel; Silva, Pedro B; Udry, Stephane

    2010-01-01

    Stellar metallicity strongly correlates with the presence of planets and their properties. To check for new correlations between stars and the existence of an orbiting planet, we determine precise stellar parameters for a sample of metal-poor solar-type stars. This sample was observed with the HARPS spectrograph and is part of a program to search for new extrasolar planets. The stellar parameters were determined using an LTE analysis based on equivalent widths (EW) of iron lines and by imposing excitation and ionization equilibrium. The ARES code was used to allow automatic and systematic derivation of the stellar parameters. Precise stellar parameters and metallicities were obtained for 97 low metal-content stars. We also present the derived masses, luminosities, and new parallaxes estimations based on the derived parameters, and compare our spectroscopic parameters with an infra-red flux method calibration to check the consistency of our method in metal poor stars. Both methods seems to give the same effect...

  5. The Anglo-Australian Planet Search Legacy

    Science.gov (United States)

    Wittenmyer, Robert A.; Tinney, Christopher G.; Butler, Paul; Horner, Jonathan; Carter, Brad; Wright, Duncan; Jones, H. R. A.

    2017-01-01

    Radial velocity searches for exoplanets have undergone a revolution in recent years: now precisions of 1 m/s or better are being demonstrated by many instruments, and new purpose-built spectrographs hold the promise of bringing Earth-mass planets into the realm of secure detectability. In the "race to the bottom," it is critical not to overlook the impact of long-running planet search programs that continue to hold the advantage of time. We highlight the continuing impact of the 18-year Anglo-Australian Planet Search: the characterisation of long-period giant planets, and the insights into the occurrence rate of Jupiter and Saturn analogs. To fully understand the origins of planetary systems and the fundamental question of how common (or rare) the architecture of the Solar system is in the Galaxy, we must continue these "legacy" surveys to probe ever-larger orbital separations.

  6. A Photometric Search for Extrasolar Planets

    Science.gov (United States)

    Howell, S. B.; Everett, M.; Davis, D. R.; Weidenschilling, S. J.; McGruder, C. H., III; Gelderman, R.

    2000-10-01

    We describe a new program for the photometric detection of extrasolar planets using the 1.3 m telescope on Kitt Peak, which will be operated by a consortium of universities headed by Western Kentucky Univ. and including South Carolina State Univ., Planetary Science Institute, Boston Univ., and UC-Berkeley (SSL). This approach will complement the existing, highly successful, spectroscopic searches. The theory of photometric transit detection has been discussed by a number of authors (e.g. Borucki & Summers 1984; Howell & Merline 1995; Howell et al. 1996) and shown to be well within the capabilities of both photomultiplier and CCD observations. The first photometric transit detection was recently accomplished for the spectroscopically discovered planet orbiting HD209458 (Henry et al. 2000). The detection of extrasolar planet transits requires high photometric precision rather than accuracy. The necessary photometric precision to detect Jupiter-, Neptune-, and Earth-sized planets in orbit around F-M dwarfs is 1%, 0.1% and 0.00001%, respectively. The required precision to observe transits by Jupiter-sized extrasolar planets is easily obtained with modern CCD detectors and the differential ensemble photometric techniques pioneered by Howell et al. (1988). The use of such a technique for ultra-high precision photometry has been described in numerous papers (Charbonneau et al. 2000, Howell 2000, plus many others). Everett and Howell recently used the Kitt Peak NOAO 0.9 m telescope with the wide-field MOSAIC camera to search for extrasolar planet transits. During this run, they achieved a photometric precision of 0.024% for this dataset. With the 1.3 m telescope, we expect to reach a photometric precision of ~ 0.01% (10-4 mag). Our consortium has recently begun to refurbish and automate the 1.3 m telescope, which will be known as the Remote-Controlled Telescope (RCT). The primary instrument will be a CCD camera with a SITe 2048 x 2048 CCD having pixel well depths of 363

  7. The Impact of Transiting Planet Science on the Next Generation of Direct-Imaging Planet Searches

    CERN Document Server

    Carson, Joseph C

    2008-01-01

    Within the next five years, a number of direct-imaging planet search instruments, like the VLT SPHERE instrument, will be coming online. To successfully carry out their programs, these instruments will rely heavily on a-priori information on planet composition, atmosphere, and evolution. Transiting planet surveys, while covering a different semi-major axis regime, have the potential to provide critical foundations for these next-generation surveys. For example, improved information on planetary evolutionary tracks may significantly impact the insights that can be drawn from direct-imaging statistical data. Other high-impact results from transiting planet science include information on mass-to-radius relationships as well as atmospheric absorption bands. The marriage of transiting planet and direct-imaging results may eventually give us the first complete picture of planet migration, multiplicity, and general evolution.

  8. The Impact of Transiting Planet Science on the Next Generation of Direct-Imaging Planet Searches

    Science.gov (United States)

    Carson, Joseph C.

    2009-02-01

    Within the next five years, a number of direct-imaging planet search instruments, like the VLT SPHERE instrument, will be coming online. To successfully carry out their programs, these instruments will rely heavily on a-priori information on planet composition, atmosphere, and evolution. Transiting planet surveys, while covering a different semi-major axis regime, have the potential to provide critical foundations for these next-generation surveys. For example, improved information on planetary evolutionary tracks may significantly impact the insights that can be drawn from direct-imaging statistical data. Other high-impact results from transiting planet science include information on mass-to-radius relationships as well as atmospheric absorption bands. The marriage of transiting planet and direct-imaging results may eventually give us the first complete picture of planet migration, multiplicity, and general evolution.

  9. Status of the Calan-Hertfordshire Extrasolar Planet Search

    Directory of Open Access Journals (Sweden)

    Jordán Andres

    2013-04-01

    Full Text Available In these proceedings we give a status update of the Calan-Hertfordshire Extrasolar Planet Search, an international collaboration led from Chile that aims to discover more planets around super metal-rich and Sun-like stars, and then follow these up with precision photometry to hunt for new bright transit planets. We highlight some results from this program, including exoplanet and brown dwarf discoveries, and a possible correlation between metallicity and planetary minimum mass at the lowest planetary masses detectable. Finally we discuss the short-term and long-term future pathways this program can take.

  10. Radio Search For Extrasolar Planets

    Science.gov (United States)

    Zarka, P.

    Theoretical justification and ongoing observational efforts in view of detecting radio emissions from extrasolar planets will be presented. On the "prediction" side, a heuris- tic scaling law has been established relating the radio output of any magnetized flow- obstacle system to the incident magnetic energy flux on the obstacle. Its confirmation by the observation of radio emission from extrasolar planets would help to understand the energy budget of such a system. On the "detection" side, specific procedures have been developed for interference mitigation and weak burst detection.

  11. The Search for Extrasolar Earth-like planets

    CERN Document Server

    Seager, S

    2003-01-01

    The search for extrasolar Earth-like planets is underway. Over 100 extrasolar giant planets are known to orbit nearby sun-like stars, including several in multiple-planet systems. These planetary systems are stepping stones for the search for Earth-like planets; the technology development, observational strategies, and science results can all be applied to Earth-like planets. Stars much less massive than the sun the most common stars in our Galaxy are being monitored for the gravitational influence of Earth-like planets. Although Earth-like planets orbiting sun-like stars are much more difficult to detect, space missions are being built to detect them indirectly due to their effects on the parent star and to quantify fundamental factors such as terrestrial planet frequency, size distribution, and mass distribution. Extremely ambitious space programs are being developed to directly detect Earth-like planets orbiting sun-like stars, and must tackle the immense technological challenge of blocking out the light o...

  12. Space based microlensing planet searches

    Directory of Open Access Journals (Sweden)

    Tisserand Patrick

    2013-04-01

    Full Text Available The discovery of extra-solar planets is arguably the most exciting development in astrophysics during the past 15 years, rivalled only by the detection of dark energy. Two projects unite the communities of exoplanet scientists and cosmologists: the proposed ESA M class mission EUCLID and the large space mission WFIRST, top ranked by the Astronomy 2010 Decadal Survey report. The later states that: “Space-based microlensing is the optimal approach to providing a true statistical census of planetary systems in the Galaxy, over a range of likely semi-major axes”. They also add: “This census, combined with that made by the Kepler mission, will determine how common Earth-like planets are over a wide range of orbital parameters”. We will present a status report of the results obtained by microlensing on exoplanets and the new objectives of the next generation of ground based wide field imager networks. We will finally discuss the fantastic prospect offered by space based microlensing at the horizon 2020–2025.

  13. Expectations from a Microlensing Search for Planets

    CERN Document Server

    Peale, S J

    1996-01-01

    The statistical distribution of the masses of planets about stars between the Sun and the center of the galaxy is constrained to within a factor of three by an intensive search for planets during microlensing events. Projected separations in terms of the lens Einstein ring radius yield a rough estimate of the distribution of planetary semimajor axes with planetary mass. The search consists of following ongoing stellar microlensing events involving sources in the center of the galaxy lensed by intervening stars with high time resolution, 1% photometry in two colors in an attempt to catch any short time scale planetary perturbations of the otherwise smooth light curve. It is assumed that 3000 events are followed over an 8 year period, but with half of the lenses, those that are members of binary systems, devoid of planets. The remaining 1500 lenses have solar-system-like distributions of 4 or 5 planets. The expectations from the microlensing search are extremely assumption dependent with 56, 138, and 81 planets...

  14. The Twenty-Five Year Lick Planet Search

    CERN Document Server

    Fischer, Debra A; Spronck, Julien F P

    2013-01-01

    The Lick planet search program began in 1987 when the first spectrum of $\\tau$ Ceti was taken with an iodine cell and the Hamilton Spectrograph. Upgrades to the instrument improved the Doppler precision from about 10 m/s in 1992 to about 3 m/s in 1995. The project detected dozens of exoplanets with orbital periods ranging from a few days to several years. The Lick survey identified the first planet in an eccentric orbit (70 Virginis) and the first multi-planet system around a normal main sequence star (Upsilon Andromedae). These discoveries advanced our understanding of planet formation and orbital migration. Data from this project helped to quantify a correlation between host star metallicity and the occurrence rate of gas giant planets. The program also served as a test bed for innovation with testing of a tip-tilt system at the coud{\\'e} focus and fiber scrambler designs to stabilize illumination of the spectrometer optics. The Lick planet search with the Hamilton spectrograph effectively ended when a heat...

  15. Selection functions in doppler planet searches

    Science.gov (United States)

    O'Toole, S. J.; Tinney, C. G.; Jones, H. R. A.; Butler, R. P.; Marcy, G. W.; Carter, B.; Bailey, J.

    2009-01-01

    We present a preliminary analysis of the sensitivity of Anglo-Australian Planet Search data to the orbital parameters of extrasolar planets. To do so, we have developed new tools for the automatic analysis of large-scale simulations of Doppler velocity planet search data. One of these tools is the two-dimensional Keplerian Lomb-Scargle (LS) periodogram that enables the straightforward detection of exoplanets with high eccentricities (something the standard LS periodogram routinely fails to do). We used this technique to redetermine the orbital parameters of HD20782b, with one of the highest known exoplanet eccentricities (e = 0.97 +/- 0.01). We also derive a set of detection criteria that do not depend on the distribution functions of fitted Keplerian orbital parameters (which we show are non-Gaussian with pronounced, extended wings). Using these tools, we examine the selection functions in orbital period, eccentricity and planet mass of Anglo-Australian Planet Search data for three planets with large-scale Monte Carlo like simulations. We find that the detectability of exoplanets declines at high eccentricities. However, we also find that exoplanet detectability is a strong function of epoch-to-epoch data quality, number of observations and period sampling. This strongly suggests that simple parametrizations of the detectability of exoplanets based on `whole-of-survey' metrics may not be accurate. We have derived empirical relationships between the uncertainty estimates for orbital parameters that are derived from least-squares Keplerian fits to our simulations and the true 99 per cent limits for the errors in those parameters, which are larger than equivalent Gaussian limits by the factors of 5-10. We quantify the rate at which false positives are made by our detection criteria, and find that they do not significantly affect our final conclusions. And finally, we find that there is a bias against measuring near-zero eccentricities, which becomes more significant

  16. The Anglo-Australian Planet Search. XXII. Two New Multi-Planet Systems

    CERN Document Server

    Wittenyer, Robert A; Tuomi, M; Salter, G S; Tinney, C G; Butler, R P; Jones, H R A; O'Toole, S J; Bailey, J; Carter, B D; Jenkins, J S; Zhang, Z; Vogt, S S; Rivera, E J

    2012-01-01

    We report the detection of two new planets from the Anglo-Australian Planet Search. These planets orbit two stars each previously known to host one planet. The new planet orbiting HD 142 has a period of 6005\\pm427 days, and a minimum mass of 5.3M_Jup. HD142c is thus a new Jupiter analog: a gas-giant planet with a long period and low eccentricity (e = 0.21 \\pm 0.07). The second planet in the HD 159868 system has a period of 352.3\\pm1.3 days, and m sin i=0.73\\pm0.05 M_Jup. In both of these systems, including the additional planets in the fitting process significantly reduced the eccentricity of the original planet. These systems are thus examples of how multiple-planet systems can masquerade as moderately eccentric single-planet systems.

  17. THE ANGLO-AUSTRALIAN PLANET SEARCH. XXII. TWO NEW MULTI-PLANET SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Wittenmyer, Robert A.; Horner, J.; Salter, G. S.; Tinney, C. G.; Bailey, J. [Department of Astrophysics, School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia); Tuomi, Mikko; Zhang, Z. [Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, College Lane, Hatfield AL10 9AB (United Kingdom); Butler, R. P. [Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015-1305 (United States); Jones, H. R. A. [Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield, AL10 9AB (United Kingdom); O' Toole, S. J. [Australian Astronomical Observatory, P.O. Box 296, Epping, NSW 1710 (Australia); Carter, B. D. [Faculty of Sciences, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia); Jenkins, J. S. [Departamento de Astronomia, Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago (Chile); Vogt, S. S.; Rivera, Eugenio J., E-mail: rob@phys.unsw.edu.au [UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States)

    2012-07-10

    We report the detection of two new planets from the Anglo-Australian Planet Search. These planets orbit two stars each previously known to host one planet. The new planet orbiting HD 142 has a period of 6005 {+-} 427 days, and a minimum mass of 5.3 M{sub Jup}. HD 142c is thus a new Jupiter analog: a gas-giant planet with a long period and low eccentricity (e = 0.21 {+-} 0.07). The second planet in the HD 159868 system has a period of 352.3 {+-} 1.3 days and m sin i = 0.73 {+-} 0.05 M{sub Jup}. In both of these systems, including the additional planets in the fitting process significantly reduced the eccentricity of the original planet. These systems are thus examples of how multiple-planet systems can masquerade as moderately eccentric single-planet systems.

  18. YETI – search for young transiting planets******

    Directory of Open Access Journals (Sweden)

    Neuhäuser Ralph

    2013-04-01

    Full Text Available We present our search for young transiting planets at ages of 2 to 20 Myr. Towards this goal, we monitor a number of young open clusters with the YETI network. YETI consists of 0.4-2 m-sized telescopes at different longitudes that observe continuously over timescales much longer than a night. In our first cluster Trumpler 37 we found more than 350 variable stars. Also two transiting candidates were found so far, for which follow-up is partly done. The first candidate turned out to be an eclipsing binary with an M-type companion. We describe the research done on these two transiting candidates.

  19. Microlensing Searches for Planets: Results and Future Prospects

    CERN Document Server

    Gaudi, B Scott

    2007-01-01

    Microlensing is potentially sensitive to multiple-planet systems containing analogs of all the solar system planets except Mercury, as well as to free floating planets. I review the landscape of microlensing planet searches, beginning with an outline of the method itself, and continuing with an overview of the results that have been obtained to date. Four planets have been detected with microlensing. I discuss what these detections have taught us about the frequency of terrestrial and giant planets with separations beyond the ``snow line.'' I then discuss the near and long-term prospects for microlensing planet searches, and in particular speculate on the expected returns of next-generation microlensing experiments both from the ground and from space. When combined with the results from other complementary surveys, next generation microlensing surveys can yield an accurate and complete census of the frequency and properties of essentially all planets with masses greater than that of Mars.

  20. The HARPS search for southern extra-solar planets XXXV. The interesting case of HD41248: stellar activity, no planets?

    CERN Document Server

    Santos, N C; Faria, J P; Dumusque, X; Adibekyan, V Zh; Delgado-Mena, E; Figueira, P; Benamati, L; Boisse, I; Cunha, D; da Silva, J Gomes; Curto, G Lo; Lovis, C; Martins, J H C; Mayor, M; Melo, C; Oshagh, M; Pepe, F; Queloz, D; Santerne, A; Segransan, D; Sozzetti, A; Sousa, S G; Udry, S

    2014-01-01

    The search for planets orbiting metal-poor stars is of uttermost importance for our understanding of the planet formation models. However, no dedicated searches have been conducted so far for very low mass planets orbiting such objects. Only a few cases of low mass planets orbiting metal-poor stars are thus known. Amongst these, HD41248 is a metal-poor, solar-type star on which a resonant pair of super-Earth like planets has In the present paper we present a new planet search program that is using the HARPS spectrograph to search for Neptunes and Super-Earths orbiting a sample of metal-poor FGK dwarfs. We then present a detailed analysis of an additional 162 radial velocity measurements of HD41248, obtained within this program, with the goal of confirming the existence of the proposed planetary system. We analyzed the precise radial velocities, obtained with the HARPS spectrograph, together with several stellar activity diagnostics and line profile indicators. A careful analysis shows no evidence for the plan...

  1. The Weihai Observatory search for close-in planets orbiting giant stars

    CERN Document Server

    Wittenmyer, Robert A; Hu, Shao Ming; Villaver, Eva; Endl, Michael; Wright, Duncan

    2015-01-01

    Planets are known to orbit giant stars, yet there is a shortage of planets orbiting within ~0.5 AU (P<100 days). First-ascent giants have not expanded enough to engulf such planets, but tidal forces can bring planets to the surface of the star far beyond the stellar radius. So the question remains: are tidal forces strong enough in these stars to engulf all the missing planets? We describe a high-cadence observational program to obtain precise radial velocities of bright giants from Weihai Observatory of Shandong University. We present data on the planet host Beta Gem (HD 62509), confirming our ability to derive accurate and precise velocities; our data achieve an rms of 7.3 m/s about the Keplerian orbit fit. This planet-search programme currently receives ~100 nights per year, allowing us to aggressively pursue short-period planets to determine whether they are truly absent.

  2. ESPRI: Astrometric planet search with PRIMA at the VLTI

    Directory of Open Access Journals (Sweden)

    Ségransan D.

    2011-07-01

    Full Text Available The ESPRI consortium will conduct an astrometric survey for extrasolar planets, using the PRIMA facility at the Very Large Telescope Interferometer. Our scientific goals include determining orbital inclinations and masses for planets already known from radial-velocity surveys, searches for planets around nearby stars of all masses, and around young stars. The consortium has built the PRIMA differential delay lines, developed an astrometric operation and calibration plan, and will deliver astrometric data reduction software.

  3. A Metric and Optimisation Scheme for Microlens Planet Searches

    CERN Document Server

    Horne, Keith; Tsapras, Yianni

    2009-01-01

    OGLE III and MOA II are discovering 600-1000 Galactic Bulge microlens events each year. This stretches the resources available for intensive follow-up monitoring of the lightcurves in search of anomalies caused by planets near the lens stars. We advocate optimizing microlens planet searches by using an automatic prioritization algorithm based on the planet detection zone area probed by each new data point. This optimization scheme takes account of the telescope and detector characteristics, observing overheads, sky conditions, and the time available for observing on each night. The predicted brightness and magnification of each microlens target is estimated by fitting to available data points. The optimisation scheme then yields a decision on which targets to observe and which to skip, and a recommended exposure time for each target, designed to maximize the planet detection capability of the observations. The optimal strategy maximizes detection of planet anomalies, and must be coupled with rapid data reduct...

  4. Search and investigation of extra-solar planets with polarimetry

    Science.gov (United States)

    Schmid, H. M.; Beuzit, J.-L.; Feldt, M.; Gisler, D.; Gratton, R.; Henning, Th.; Joos, F.; Kasper, M.; Lenzen, R.; Mouillet, D.; Moutou, C.; Quirrenbach, A.; Stam, D. M.; Thalmann, C.; Tinbergen, J.; Verinaud, C.; Waters, R.; Wolstencroft, R.

    Light reflected from planets is polarized. This basic property of planets provides the possibility for detecting and characterizing extra-solar planets using polarimetry. The expected polarization properties of extra-solar planets are discussed that can be inferred from polarimetry of "our" solar system planets. They show a large variety of characteristics depending on the atmospheric and/or surface properties. Best candidates for a polarimetric detection are extra-solar planets with an optically thick Rayleigh scattering layer.Even the detection of highly polarized extra-solar planets requires a very sophisticated instrument. We present the results from a phase A (feasibility) study for a polarimetric arm in the ESO VLT planet finder instrument. It is shown that giant planets around nearby stars can be searched and investigated with an imaging polarimeter, combined with a powerful AO system and a coronagraph at an 8 m class telescope.A similar type of polarimeter is also considered for the direct detection of terrestrial planets using an AO system on one of the future Extremely Large Telescopes.

  5. The HARPS-N Rocky Planet Search

    DEFF Research Database (Denmark)

    Motalebi, F.; Udry, S.; Gillon, M.

    2015-01-01

    We know now from radial velocity surveys and transit space missions that planets only a few times more massive than our Earth are frequent around solar-type stars. Fundamental questions about their formation history, physical properties, internal structure, and atmosphere composition are, however...

  6. Searching for Planets using Particle Swarm Optimization

    Science.gov (United States)

    Chambers, John E.

    2008-05-01

    The Doppler radial velocity technique has been highly successful in discovering planetary-mass companions in orbit around nearby stars. A typical data set contains around one hundred instantaneous velocities for the star, spread over a period of several years,with each observation measuring only the radial component of velocity. From this data set, one would like to determine the masses and orbital parameters of the system of planets responsible for the star's reflex motion. Assuming coplanar orbits, each planet is characterized by five parameters, with an additional parameter for each telescope used to make observations, representing the instrument's velocity offset. The large number of free parameters and the relatively sparse data sets make the fitting process challenging when multiple planets are present, especially if some of these objects have low masses. Conventional approaches using periodograms often perform poorly when the orbital periods are not separated by large amounts or the longest period is comparable to the length of the data set. Here, I will describe a new approach to fitting Doppler radial velocity sets using particle swarm optimization (PSO). I will describe how the PSO method works, and show examples of PSO fits to existing radial velocity data sets, with comparisons to published solutions and those submitted to the Systemic website (http://www.oklo.org).

  7. The Calan-Hertfordshire extrasolar planet search

    Directory of Open Access Journals (Sweden)

    Pinfield D.J.

    2011-07-01

    Full Text Available The detailed study of the exoplanetary systems HD189733 and HD209458 has given rise to a wealth of exciting information on the physics of exoplanetary atmospheres. To further our understanding of the make-up and processes within these atmospheres we require a larger sample of bright transiting planets. We have began a project to detect more bright transiting planets in the southern hemisphere by utilising precision radial-velocity measurements. We have observed a constrained sample of bright, inactive and metal-rich stars using the HARPS instrument and here we present the current status of this project, along with our first discoveries which include a brown dwarf/extreme-Jovian exoplanet found in the brown dwarf desert region around the star HD191760 and improved orbits for three other exoplanetary systems HD48265, HD143361 and HD154672. Finally, we briefly discuss the future of this project and the current prospects we have for discovering more bright transiting planets.

  8. Detecting circumbinary planets: A new quasi-periodic search algorithm

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    Pollacco D.

    2013-04-01

    Full Text Available We present a search method based around the grouping of data residuals, suitable for the detection of many quasi-periodic signals. Combined with an efficient and easily implemented method to predict the maximum transit timing variations of a transiting circumbinary exoplanet, we form a fast search algorithm for such planets. We here target the Kepler dataset in particular, where all the transiting examples of circumbinary planets have been found to date. The method is presented and demonstrated on two known systems in the Kepler data.

  9. A new search for planet transits in NGC 6791

    CERN Document Server

    Montalto, M; Desidera, S; De Marchi, F; Bruntt, H; Stetson, P B; Ferro, A Arellano; Momany, Y; Gratton, R G; Poretti, E; Aparicio, A; Barbieri, M; Claudi, R U; Grundahl, G; Rosenberg, A L

    2007-01-01

    Context. Searching for planets in open clusters allows us to study the effects of dynamical environment on planet formation and evolution. Aims. Considering the strong dependence of planet frequency on stellar metallicity, we studied the metal rich old open cluster NGC 6791 and searched for close-in planets using the transit technique. Methods. A ten-night observational campaign was performed using the Canada-France-Hawaii Telescope (3.6m), the San Pedro M\\'artir telescope (2.1m), and the Loiano telescope (1.5m). To increase the transit detection probability we also made use of the Bruntt et al. (2003) eight-nights observational campaign. Adequate photometric precision for the detection of planetary transits was achieved. Results. Should the frequency and properties of close-in planets in NGC 6791 be similar to those orbiting field stars of similar metallicity, then detailed simulations foresee the presence of 2-3 transiting planets. Instead, we do not confirm the transit candidates proposed by Bruntt et al. ...

  10. A search for rocky planets transiting brown dwarfs

    CERN Document Server

    Triaud, Amaury H M J; Selsis, Franck; Winn, Joshua N; Demory, Brice-Olivier; Artigau, Etienne; Laughlin, Gregory P; Seager, Sara; Helling, Christiane; Mayor, Michel; Albert, Loic; Anderson, Richard I; Bolmont, Emeline; Doyon, Rene; Forveille, Thierry; Hagelberg, Janis; Leconte, Jeremy; Lendl, Monika; Littlefair, Stuart; Raymond, Sean; Sahlmann, Johannes

    2013-01-01

    Exoplanetary science has reached a historic moment. The James Webb Space Telescope will be capable of probing the atmospheres of rocky planets, and perhaps even search for biologically produced gases. However this is contingent on identifying suitable targets before the end of the mission. A race therefore, is on, to find transiting planets with the most favorable properties, in time for the launch. Here, we describe a realistic opportunity to discover extremely favorable targets - rocky planets transiting nearby brown dwarfs - using the Spitzer Space Telescope as a survey instrument. Harnessing the continuous time coverage and the exquisite precision of Spitzer in a 5,400 hour campaign monitoring nearby brown dwarfs, we will detect a handful of planetary systems with planets as small as Mars. The survey we envision is a logical extension of the immense progress that has been realized in the field of exoplanets and a natural outcome of the exploration of the solar neighborhood to map where the nearest habitab...

  11. The Pan-Pacific Planet Search. VI. Giant Planets Orbiting HD 86950 and HD 222076

    Science.gov (United States)

    Wittenmyer, Robert A.; Jones, M. I.; Zhao, Jinglin; Marshall, J. P.; Butler, R. P.; Tinney, C. G.; Wang, Liang; Johnson, John Asher

    2017-02-01

    We report the detection of two new planets orbiting the K giants HD 86950 and HD 222076, based on precise radial velocities obtained with three instruments: AAT/UCLES, FEROS, and CHIRON. HD 86950b has a period of 1270 ± 57 days at a=2.72+/- 0.08 au, and m sin i=3.6+/- 0.7 {M}{Jup}. HD 222076b has P=871+/- 19 days at a=1.83+/- 0.03 au, and m sin i=1.56+/- 0.11 {M}{Jup}. These two giant planets are typical of the population of planets known to orbit evolved stars. In addition, we find a high-amplitude periodic velocity signal (K∼ 50 m s‑1) in HD 29399 and show that it is due to stellar variability rather than Keplerian reflex motion. We also investigate the relation between planet occurrence and host-star metallicity for the 164-star Pan-Pacific Planet Search (PPPS) sample of evolved stars. In spite of the small sample of PPPS detections, we confirm the trend of increasing planet occurrence as a function of metallicity found by other studies of planets orbiting evolved stars.

  12. The Pan-Pacific Planet Search VI: Giant planets orbiting HD 86950 and HD 222076

    CERN Document Server

    Wittenmyer, Robert A; Zhao, Jinglin; Marshall, J P; Butler, R P; Tinney, C G; Wang, Liang; Johnson, John Asher

    2016-01-01

    We report the detection of two new planets orbiting the K giants HD 86950 and HD 222076, based on precise radial velocities obtained with three instruments: AAT/UCLES, FEROS, and CHIRON. HD 86950b has a period of 1270$\\pm$57 days at $a=2.72\\pm$0.08 AU, and m sin $i=3.6\\pm$0.7 Mjup. HD 222076b has $P=871\\pm$19 days at $a=1.83\\pm$0.03 AU, and m sin $i=1.56\\pm$0.11 Mjup. These two giant planets are typical of the population of planets known to orbit evolved stars. In addition, we find a high-amplitude periodic velocity signal ($K\\sim$50 m/s) in HD 29399, and show that it is due to stellar variability rather than Keplerian reflex motion. We also investigate the relation between planet occurrence and host-star metallicity for the 164-star Pan-Pacific Planet Search sample of evolved stars. In spite of the small sample of PPPS detections, we confirm the trend of increasing planet occurrence as a function of metallicity found by other studies of planets orbiting evolved stars.

  13. The Space Stellar Photometry Mission COROT: Asteroseismology and Search for Extrasolar Planets

    Indian Academy of Sciences (India)

    Annie Baglin; Gerard Vauclair; Corot team

    2000-09-01

    The main scientific objectives, asteroseismology and search for extrasolar planets for the COROT photometric mission are presented, and its interest in terms of stellar variability. A description of the payload, details of the scientific program, the ground based preparatory observations and bibliography can be found at http://www.astrsp-mrs.fr/corot/pagecorot.html.

  14. Direct imaging searches for planets around white dwarf stars

    Science.gov (United States)

    Burleigh, Matt; Hogan, Emma; Clarke, Fraser

    White dwarfs are excellent targets for direct imaging searches for extra-solar planets, since they are up to 10^4 times fainter than their main sequence progenitors, providing a huge gain in the contrast problem. In addition, the orbits of planetary companions that lie beyond the maximum extent of the Red Giant envelope are expected to widen considerably, improving resolution and further encouraging direct detection. We discuss current searches for planetary companions to white dwarfs, including our own “DODO” programme. At the time of writing, no planetary companion to a white dwarf has been detected. The most sensitive searches have been capable of detecting companions ≳5M_{Jup}, and their non-detection is consistent with the conclusions of McCarthy & Zuckerman (2004), that no more than 3% of stars harbour 5-10M_{Jup} planets at orbits between 75-300AU. Extremely Large Telescopes are required to enable deeper searches sensitive to lower mass planets, and to provide larger target samples including more distant and older white dwarfs. ELTs will also enable spectroscopic follow-up for any resolved planets, and follow-up of any planetary companions discovered astrometrically by GAIA and SIM.

  15. In search of planets and life around other stars.

    Science.gov (United States)

    Lunine, J I

    1999-05-11

    The discovery of over a dozen low-mass companions to nearby stars has intensified scientific and public interest in a longer term search for habitable planets like our own. However, the nature of the detected companions, and in particular whether they resemble Jupiter in properties and origin, remains undetermined.

  16. Optimizing the search for transiting planets in long time series

    Science.gov (United States)

    Ofir, Aviv

    2014-01-01

    Context. Transit surveys, both ground- and space-based, have already accumulated a large number of light curves that span several years. Aims: The search for transiting planets in these long time series is computationally intensive. We wish to optimize the search for both detection and computational efficiencies. Methods: We assume that the searched systems can be described well by Keplerian orbits. We then propagate the effects of different system parameters to the detection parameters. Results: We show that the frequency information content of the light curve is primarily determined by the duty cycle of the transit signal, and thus the optimal frequency sampling is found to be cubic and not linear. Further optimization is achieved by considering duty-cycle dependent binning of the phased light curve. By using the (standard) BLS, one is either fairly insensitive to long-period planets or less sensitive to short-period planets and computationally slower by a significant factor of ~330 (for a 3 yr long dataset). We also show how the physical system parameters, such as the host star's size and mass, directly affect transit detection. This understanding can then be used to optimize the search for every star individually. Conclusions: By considering Keplerian dynamics explicitly rather than implicitly one can optimally search the BLS parameter space. The presented Optimal BLS enhances the detectability of both very short and very long period planets, while allowing such searches to be done with much reduced resources and time. The Matlab/Octave source code for Optimal BLS is made available. The MATLAB code is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/561/A138

  17. The Magellan PFS Planet Search Program: Radial Velocity and Stellar Abundance Analyses of the 360 au, Metal-poor Binary “Twins” HD 133131A & B

    Science.gov (United States)

    Teske, Johanna K.; Shectman, Stephen A.; Vogt, Steve S.; Díaz, Matías; Butler, R. Paul; Crane, Jeffrey D.; Thompson, Ian B.; Arriagada, Pamela

    2016-12-01

    We present a new precision radial velocity (RV) data set that reveals multiple planets orbiting the stars in the ˜360 au, G2+G2 “twin” binary HD 133131AB. Our six years of high-resolution echelle observations from MIKE and five years from the Planet Finder Spectrograph (PFS) on the Magellan telescopes indicate the presence of two eccentric planets around HD 133131A with minimum masses of 1.43 ± 0.03 and 0.63 ± 0.15 {{ M }}{{J}} at 1.44 ± 0.005 and 4.79 ± 0.92 au, respectively. Additional PFS observations of HD 133131B spanning five years indicate the presence of one eccentric planet of minimum mass 2.50 ± 0.05 {{ M }}{{J}} at 6.40 ± 0.59 au, making it one of the longest-period planets detected with RV to date. These planets are the first to be reported primarily based on data taken with the PFS on Magellan, demonstrating the instrument’s precision and the advantage of long-baseline RV observations. We perform a differential analysis between the Sun and each star, and between the stars themselves, to derive stellar parameters and measure a suite of 21 abundances across a wide range of condensation temperatures. The host stars are old (likely ˜9.5 Gyr) and metal-poor ([Fe/H] ˜ -0.30), and we detect a ˜0.03 dex depletion in refractory elements in HD 133131A versus B (with standard errors ˜0.017). This detection and analysis adds to a small but growing sample of binary “twin” exoplanet host stars with precise abundances measured, and represents the most metal-poor and likely oldest in that sample. Overall, the planets around HD 133131A and B fall in an unexpected regime in planet mass-host star metallicity space and will serve as an important benchmark for the study of long-period giant planets. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

  18. The Magellan PFS Planet Search Program: Radial Velocity and Stellar Abundance Analyses of the 360 AU, Metal-Poor Binary "Twins" HD 133131A & B

    CERN Document Server

    Teske, Johanna K; Vogt, Steve S; Díaz, Matías; Butler, R Paul; Crane, Jeffrey D; Thompson, Ian B; Arriagada, Pamela

    2016-01-01

    We present a new precision radial velocity (RV) dataset that reveals multiple planets orbiting the stars in the $\\sim$360 AU, G2$+$G2 "twin" binary HD 133131AB. Our 6 years of high-resolution echelle observations from MIKE and 5 years from PFS on the Magellan telescopes indicate the presence of two eccentric planets around HD 133131A with minimum masses of 1.43$\\pm$0.03 and 0.63$\\pm$0.15 $\\mathcal{M}_{\\rm J}$ at 1.44$\\pm$0.005 and 4.79$\\pm$0.92 AU, respectively. Additional PFS observations of HD 133131B spanning 5 years indicate the presence of one eccentric planet of minimum mass 2.50$\\pm$0.05 $\\mathcal{M}_{\\rm J}$ at 6.40$\\pm$0.59 AU, making it one of the longest period planets detected with RV to date. These planets are the first to be reported primarily based on data taken with PFS on Magellan, demonstrating the instrument's precision and the advantage of long-baseline RV observations. We perform a differential analysis between the Sun and each star, and between the stars themselves, to derive stellar par...

  19. A SYSTEMATIC SEARCH FOR TROJAN PLANETS IN THE KEPLER DATA

    Energy Technology Data Exchange (ETDEWEB)

    Janson, Markus, E-mail: janson@astro.princeton.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2013-09-10

    Trojans are circumstellar bodies that reside in characteristic 1:1 orbital resonances with planets. While all the trojans in our solar system are small ({approx}<100 km), stable planet-size trojans may exist in extrasolar planetary systems, and the Kepler telescope constitutes a formidable tool to search for them. Here we report on a systematic search for extrasolar trojan companions to 2244 known Kepler Objects of Interest (KOIs), with epicyclic orbital characteristics similar to those of the Jovian trojan families. No convincing trojan candidates are found, despite a typical sensitivity down to Earth-size objects. This fact, however, cannot be used to stringently exclude the existence of trojans in this size range, since stable trojans need not necessarily share the same orbital plane as the planet, and thus may not transit. Following this reasoning, we note that if Earth-sized trojans exist at all, they are almost certainly both present and in principle detectable in the full set of Kepler data, although a very substantial computational effort would be required to detect them. Additionally, we also note that some of the existing KOIs could in principle be trojans themselves, with a primary planet orbiting outside of the transiting plane. A few examples are given for which this is a readily testable scenario.

  20. Optimizing the search for transiting planets in long time series

    CERN Document Server

    Ofir, Aviv

    2013-01-01

    Context: Transit surveys, both ground- and space- based, have already accumulated a large number of light curves that span several years. Aims: The search for transiting planets in these long time series is computationally intensive. We wish to optimize the search for both detection and computational efficiencies. Methods: We assume that the searched systems can be well described by Keplerian orbits. We then propagate the effects of different system parameters to the detection parameters. Results: We show that the frequency information content of the light curve is primarily determined by the duty cycle of the transit signal, and thus the optimal frequency sampling is found to be cubic and not linear. Further optimization is achieved by considering duty-cycle dependent binning of the phased light curve. By using the (standard) BLS one is either rather insensitive to long-period planets, or less sensitive to short-period planets and computationally slower by a significant factor of ~330 (for a 3yr long dataset...

  1. Searching for Life on Habitable Planets and Moons

    CERN Document Server

    Lal, Ashwini Kumar

    2010-01-01

    Earth is the only known inhabited planet in the universe to date. However, advancements in the fields of astrobiology and observational astronomy, and the discovery of large varieties of extremophiles with extraordinary capablities to thrive in harshest environments on Earth, have led to speculation that life may be thriving on many of the extraterrestrial bodies in the universe. Coupled with the growing number of exoplanets detected over the past decade, the search for the possibility of life on other planets and satellites within the solar system and beyond has become a passion as well as a challenge for scientists in a variety of fields. This paper examines such possibility of finding life, in the light of findings of the numerous space probes and theoretical research undertaken in this field over the past few decades.

  2. Trigonometric Parallaxes and Proper Motions of 134 Southern Late M, L, and T Dwarfs from the Carnegie Astrometric Planet Search Program

    CERN Document Server

    Weinberger, A J; Keiser, S A; Anglada-Escudé, G; Thompson, I B; Burley, G

    2016-01-01

    We report trigonometric parallaxes for 134 low mass stars and brown dwarfs, of which 38 have no previously published measurement and 79 more have improved uncertainties. Our survey targeted nearby targets, so 119 are closer than 30 pc. Of the 38 stars with new parallaxes, 14 are within 20 pc and seven are likely brown dwarfs (spectral types later than L0). These parallaxes are useful for studies of kinematics, multiplicity, and spectrophotometric calibration. Two objects with new parallaxes are confirmed as young stars with membership in nearby young moving groups: LP 870-65 in AB Doradus and G 161-71 in Argus. We also report the first parallax for the planet-hosting star GJ 3470; this allows us to refine the density of its Neptune-mass planet. One T-dwarf, 2MASS J12590470-4336243, previously thought to lie within 4 pc, is found to be at 7.8 pc, and the M-type star 2MASS J01392170-3936088 joins the ranks of nearby stars as it is found to be within 10 pc. Five stars that are over-luminous and/or too red for th...

  3. Trigonometric Parallaxes and Proper Motions of 134 Southern Late M, L, and T Dwarfs from the Carnegie Astrometric Planet Search Program

    Science.gov (United States)

    Weinberger, Alycia J.; Boss, Alan P.; Keiser, Sandra A.; Anglada-Escudé, Guillem; Thompson, Ian B.; Burley, Gregory

    2016-07-01

    We report trigonometric parallaxes for 134 low-mass stars and brown dwarfs, of which 38 have no previously published measurement and 79 more have improved uncertainties. Our survey focused on nearby targets, so 119 are closer than 30 pc. Of the 38 stars with new parallaxes, 14 are within 20 pc and seven are likely brown dwarfs (spectral types later than L0). These parallaxes are useful for studies of kinematics, multiplicity, and spectrophotometric calibration. Two objects with new parallaxes are confirmed as young stars with membership in nearby young moving groups: LP 870-65 in AB Doradus and G 161-71 in Argus. We also report the first parallax for the planet-hosting star GJ 3470; this allows us to refine the density of its Neptune-mass planet. T-dwarf 2MASS J12590470-4336243, previously thought to lie within 4 pc, is found to be at 7.8 pc, and the M-type star 2MASS J01392170-3936088 joins the ranks of nearby stars as it is found to be within 10 pc. Five stars that are overluminous and/or too red for their spectral types are identified and deserve further study as possible young stars.

  4. Kepler AutoRegressive Planet Search: Motivation & Methodology

    Science.gov (United States)

    Caceres, Gabriel; Feigelson, Eric; Jogesh Babu, G.; Bahamonde, Natalia; Bertin, Karine; Christen, Alejandra; Curé, Michel; Meza, Cristian

    2015-08-01

    The Kepler AutoRegressive Planet Search (KARPS) project uses statistical methodology associated with autoregressive (AR) processes to model Kepler lightcurves in order to improve exoplanet transit detection in systems with high stellar variability. We also introduce a planet-search algorithm to detect transits in time-series residuals after application of the AR models. One of the main obstacles in detecting faint planetary transits is the intrinsic stellar variability of the host star. The variability displayed by many stars may have autoregressive properties, wherein later flux values are correlated with previous ones in some manner. Auto-Regressive Moving-Average (ARMA) models, Generalized Auto-Regressive Conditional Heteroskedasticity (GARCH), and related models are flexible, phenomenological methods used with great success to model stochastic temporal behaviors in many fields of study, particularly econometrics. Powerful statistical methods are implemented in the public statistical software environment R and its many packages. Modeling involves maximum likelihood fitting, model selection, and residual analysis. These techniques provide a useful framework to model stellar variability and are used in KARPS with the objective of reducing stellar noise to enhance opportunities to find as-yet-undiscovered planets. Our analysis procedure consisting of three steps: pre-processing of the data to remove discontinuities, gaps and outliers; ARMA-type model selection and fitting; and transit signal search of the residuals using a new Transit Comb Filter (TCF) that replaces traditional box-finding algorithms. We apply the procedures to simulated Kepler-like time series with known stellar and planetary signals to evaluate the effectiveness of the KARPS procedures. The ARMA-type modeling is effective at reducing stellar noise, but also reduces and transforms the transit signal into ingress/egress spikes. A periodogram based on the TCF is constructed to concentrate the signal

  5. The SOPHIE search for northern extrasolar planets. II. A multiple planet system around HD 9446

    Science.gov (United States)

    Hébrard, G.; Bonfils, X.; Ségransan, D.; Moutou, C.; Delfosse, X.; Bouchy, F.; Boisse, I.; Arnold, L.; Desort, M.; Díaz, R. F.; Eggenberger, A.; Ehrenreich, D.; Forveille, T.; Lagrange, A.-M.; Lovis, C.; Pepe, F.; Perrier, C.; Pont, F.; Queloz, D.; Santos, N. C.; Udry, S.; Vidal-Madjar, A.

    2010-04-01

    We report the discovery of a planetary system around HD 9446, performed from radial velocity measurements secured with the spectrograph SOPHIE at the 193-cm telescope of the Haute-Provence Observatory for more than two years. At least two planets orbit this G5V, active star: HD 9446b has a minimum mass of 0.7 MJup and a slightly eccentric orbit with a period of 30 days, whereas HD 9446c has a minimum mass of 1.8 MJup and a circular orbit with a period of 193 days. As for most of the known multiple planet systems, the HD 9446-system presents a hierarchical disposition with a massive outer planet and a lighter inner planet. Based on observations collected with the SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS), France, by the SOPHIE Consortium (program 07A.PNP.CONS). The full version of Table 1 (SOPHIE measurements of HD 9446) is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/513/A69

  6. Searching for circumbinary planets with CB-BLS

    Science.gov (United States)

    Ofir, Aviv

    2015-08-01

    Transiting circumbinary planets (CBP) produce transit signals that are neither periodic not constant in duration or depth. These complications contribute to the low number of detected transiting CBP (nine in total so far), and limited detection to systems that exhibit transits that are relatively deep, i.e. individually-significant transit events. Planets around single stars taught us that small planets far outnumber larger ones, consequently the ability to detect small CBP is of the essence in order to correctly describe CBP demographics. Unfortunately, all currently known transiting CBP were detected either by eye or by some ad-hoc technique that has nothing to do with the 3-body dynamics of CBP (e.g. QATS, Carter & Agol 2013) -- limiting their detection power. CB-BLS (Ofir 2008) is an algorithm for the detection of transiting CBP that was proposed well before the first transiting CBP was detected (Doyle et al 2011). CB-BLS is tailored for CBP dynamics and is optimally sensitive and general. Here we present further evolution and the Matlab source code of CB-BLS that allows it to detect all currently known transiting CBP, including in eccentric and/or inclined orbits. We then describe our preliminary results on searching for transiting CBP in a small subset of the Kepler eclipsing binaries.

  7. HD 80606: searching for the chemical signature of planet formation

    Science.gov (United States)

    Saffe, C.; Flores, M.; Buccino, A.

    2015-10-01

    Context. Binary systems with similar components are ideal laboratories that allow several physical processes to be tested, such as the possible chemical pattern imprinted by the planet formation process. Aims: We explore the probable chemical signature of planet formation in the remarkable binary system HD 80606-HD 80607. The star HD 80606 hosts a giant planet with ~4 MJup detected by both transit and radial velocity techniques, which is one of the most eccentric planets detected to date. We study condensation temperature Tc trends of volatile and refractory element abundances to determine whether there is a depletion of refractories, which could be related to the terrestrial planet formation. Methods: We carried out a high-precision abundance determination in both components of the binary system via a line-by-line, strictly differential approach. First, we used the Sun as a reference and then we used HD 80606. The stellar parameters Teff, log g, [Fe/H] and vturb were determined by imposing differential ionization and excitation equilibrium of Fe I and Fe II lines, with an updated version of the program FUNDPAR, together with plane-parallel local thermodynamic equilibrium (LTE) ATLAS9 model atmospheres and the MOOG code. Then, we derived detailed abundances of 24 different species with equivalent widths and spectral synthesis with the program MOOG. The chemical patterns were compared with the solar-twins Tc trends of Meléndez et al. (2009, AJ, 704, L66) and with a sample of solar-analogue stars with [Fe/H] ~ +0.2 dex from Neves et al. (2009, A&A, 497, 563). The Tc trends were also compared mutually between both stars of the binary system. Results: From the study of Tc trends, we concluded that the stars HD 80606 and HD 80607 do not seem to be depleted in refractory elements, which is different for the case of the Sun. Then, following the interpretation of Meléndez et al. (2009), the terrestrial planet formation would have been less efficient in the components of

  8. Habitable Worlds Around M Dwarf Stars: The CAPSCam Astrometric Planet Search

    Science.gov (United States)

    Boss, Alan P.; Weinberger, Alycia J.; Anglada-Escudé, Guillem; Thompson, Ian B.; Brahm, Rafael

    2014-04-01

    M dwarf stars are attractive targets in the search for habitable worlds as a result of their relative abundance and proximity, making them likely targets for future direct detection efforts. Hot super-Earths as well as gas giants have already been detected around a number of early M dwarfs, and the former appear to be the high-mass end of the population of rocky, terrestrial exoplanets. The Carnegie Astrometric Planet Search (CAPS) program has been underway since March 2007, searching ~ 100 nearby late M, L, and T dwarfs for gas giant planets on orbits wide enough for habitable worlds to orbit interior to them. The CAPSCam-N camera on the 2.5-m du Pont telescope at the Las Campanas Observatory has demonstrated the ability to detect planets as low in mass as Saturn orbiting at several AU around late M dwarfs within 15 pc. Over the next decade, the CAPS program will provide new constraints on the planetary census around late M dwarf stars, and hence on the suitability of these nearby planetary systems for supporting life.

  9. A New Channel to Search for Extra-solar Systems with Multiple Planets via Gravitational Microlensing

    CERN Document Server

    Han, C; Han, Cheongho; Park, Myeong-Gu

    2002-01-01

    Gaudi, Naber & Sackett pointed out that if an event is caused by a lens system containing more than two planets, all planets will affect the central region of the magnification pattern, and thus the existence of the multiple planets can be inferred by detecting additionally deformed anomalies from intensive monitoring of high magnification events. Unfortunately, this method has important limitations in identifying the existence of multiple planets and determining their parameters due to the degeneracy of the resulting light curve anomalies from those induced by a single planet and the complexity of multiple planet lensing models. In this paper, we propose a new channel to search for multiple planets via microlensing. The method is based on the fact that the anomalies induced by multiple planets are well approximated by the superposition of those of the single planet systems where the individual planet-primary pairs act as independent lens systems. Then, if the source trajectory passes both of the outer de...

  10. A Search for Planet 9 at the Thacher Observatory

    Science.gov (United States)

    Edwards, Nick; Kirkpatrick, Liam; O'Neill, Kathleen; Yin, Yao; Wood, Asher; Swift, Jonathan

    2017-01-01

    The recent inference that there may be a massive planet in the outer solar system has sparked much excitement and debate. A dedicated program, at the newly renovated Thacher Observatory, is designed to cover approximately 36 square degrees of sky where it is most likely to be found during the 2016-2017 observing season. The depth of the survey will reach 23rd magnitude in V band, and we will use an observing cadence in accord with its expected proper motion. Here we present the detailed parameters and first images from the survey.

  11. The (Historical) Search for Planets Orbiting Proxima Centauri

    Science.gov (United States)

    Kohler, Susanna

    2016-08-01

    The European Southern Observatory (ESO) is widely expected to address the reportsofthe discovery of a planet orbiting our nearest stellar neighbor, Proxima Centauri, today. Due to its proximity 4.25 light-years away this red dwarf star has been a prime target for exoplanet searches throughout the last couple decades.Hubble image of Proxima Centauri, our nearest stellar neighbor. [ESA/Hubble]In anticipation of ESOspress conference this afternoon, lets take a look at someof the past work in the search for planetary companions around Proxima Centauri.The Early Years of Exploring Proxima CentauriProxima Centauri was discovered by astronomer Robert Innes in 1915. Studies of this star over the next eighty years primarily focused on better understanding its orbital motion (is it part of the Alpha Centauri star system?) and its flaring nature. But in the 1990s, after the detection of the first exoplanets, Proxima Centauri became a target for its potential to host planet-mass companions.Top: Images of Proxima Centauri on two different days from Hubbles FOS instrument. The bar across the center is an occulter that partially blocks the light from Proxima Centauri. Middle: Reconstructed images allowing a closer look at a moving feature identified by the authors as a possible companion. Bottom: diagram of the position of the planet candidate (box) relative to Proxima Centauri (star) in the two frames. [Schultz et al. 1998]1990s: A Possible Planet Detected With Hubble?In January 1998, a paper led by A.B. Schultz (STScI) reported the possible visual detection of a planetary companion to Proxima Centauri. Observations from Hubbles Faint Object Spectrograph, which was being used as a coronagraphic camera, revealed excess light that could be interpreted as a substellar object located ~0.5 AU from Proxima Centauri, a small separation that could imply either a short (~1 yr) period or a highly eccentric orbit.But follow-up observations led by David Golimowski (Johns Hopkins University

  12. Priming the Solar Neighborhood M dwarfs for Future Planet Searches

    Science.gov (United States)

    Dittmann, Jason

    2016-01-01

    The nearby low-mass stars are the best candidate hosts for searching for transiting exoplanets to enable atmospheric characterization. Unfortunately, our understanding of exoplanets is most often limited by our ability to characterize the host star. My thesis has focused on this stellar characterization problem. MEarth consists of 2 arrays of 8 telescopes each, one located at Mt. Hopkins, Arizona, and the other at Cerro Tololo, Chile. First, I used data from the Northern array to measure the trigonometric parallax of 1500 northern M dwarfs with a precision of 3 mas. With these distances we better characterized the MEarth M dwarfs and selected a volume-limited sample from which to search for planets. Second, I calibrated the MEarth photometric system using observations of Landolt standard fields. We measured the red-optical MEarth magnitude for 1800 M dwarfs with 1.5% precision. Combined with trigonometric parallaxes and spectroscopic metallicity estimates, I created a color-magnitude-metallicity relation for the mid-to-late M dwarfs capable of reproducing spectral metallicities with 0.1 dex precision. With these metallicities, we plan to measure any potential planet-metallicity correlation at the low-mass end of the stellar sequence once future missions uncover the planets orbiting these stars. Third, I present MEarth-South's discovery of a low mass eclipsing binary system. The system has an orbital period of 4.7 days, possesses zero eccentricity but is non-synchronously rotating. We obtained high precision radial velocity measurements from the TRES spectrograph, allowing us to measure the mass of each component with 1% precision. Both components are slightly inflated compared to the most recent stellar models, in keeping with previous precise mass-radius determinations for low mass stars. Fourth, I am currently gathering sloan photometry for M dwarfs to calibrate a color-color metallicity relation in the sloan bandpass. My thesis has focused on characterizing the

  13. Microlensing Search for Planets with Two Simultaneously Rising Suns

    CERN Document Server

    Han, Cheongho

    2008-01-01

    Among more than 200 extrasolar planet candidates discovered to date, there is no known planet orbiting around normal binary stars. In this paper, we demonstrate that microlensing is a technique that can detect such planets. Microlensing discoveries of these planets are possible because the planet and host binary stars produce perturbations at a common region around center of mass of the binary stars and thus the signatures of both planet and binary can be detected in the light curves of high-magnification microlensing events. The ranges of the planetary and binary separations of systems for optimal detection vary depending on the planet mass. For a Jupiter-mass planet, we find that high detection efficiency is expected for planets located in the range of $\\sim$ 1 AU -- 5 AU from the binary stars which are separated by $\\sim$ 0.15 AU -- 0.5 AU

  14. The HARPS search for southern extra-solar planets. X. A m sin i = 11 Mearth planet around the nearby spotted M dwarf GJ 674

    CERN Document Server

    Bonfils, X; Delfosse, X; Forveille, T; Gillon, M; Perrier, C; Udry, S; Bouchy, F; Lovis, C; Pepe, F; Queloz, D; Santos, N C; Bertaux, J -L

    2007-01-01

    Context: How planet properties depend on stellar mass is a key diagnostic of planetary formation mechanisms. Aims: This motivates planet searches around stars which are significantly more massive or less massive than the Sun, and in particular our radial velocity search for planets around very-low mass stars. Methods: As part of that program, we obtained measurements of GJ 674, an M2.5 dwarf at d=4.5 pc, which have a dispersion much in excess of their internal errors. An intensive observing campaign demonstrates that the excess dispersion is due to two superimposed coherent signals, with periods of 4.69 and 35 days. Results: These data are well described by a 2-planet Keplerian model where each planet has a ~11 Mearth minimum mass. A careful analysis of the (low level) magnetic activity of GJ 674 however demonstrates that the 35-day period coincides with the stellar rotation period. This signal therefore originates in a spot inhomogeneity modulated by stellar rotation. The 4.69-day signal on the other hand is...

  15. DARWIN - A Mission to Detect, and Search for Life on, Extrasolar Planets

    CERN Document Server

    Cockell, C S; Fridlund, M; Herbst, T; Kaltenegger, L; Absil, O; Beichman, C; Benz, W; Blanc, M; Brack, A; Chelli, A; Colangeli, L; Cottin, H; Foresto, V Coude du; Danchi, W; Defrere, D; Herder, J -W den; Eiroa, C; Greaves, J; Henning, T; Johnston, K; Jones, H; Labadie, L; Lammer, H; Launhardt, R; Lawson, P; Lay, O P; LeDuigou, J -M; Liseau, R; Malbet, F; Martin, S R; Mawet, D; Mourard, D; Moutou, C; Mugnier, L; Paresce, F; Quirrenbach, Andreas G; Rabbia, Y; Raven, J A; Röttgering, H J A; Rouan, D; Santos, N; Selsis, F; Serabyn, E; Shibai, H; Tamura, M; Thiebaut, E; Westall, F; White,; Glenn, J

    2008-01-01

    The discovery of extra-solar planets is one of the greatest achievements of modern astronomy. The detection of planets with a wide range of masses demonstrates that extra-solar planets of low mass exist. In this paper we describe a mission, called Darwin, whose primary goal is the search for, and characterization of, terrestrial extrasolar planets and the search for life. Accomplishing the mission objectives will require collaborative science across disciplines including astrophysics, planetary sciences, chemistry and microbiology. Darwin is designed to detect and perform spectroscopic analysis of rocky planets similar to the Earth at mid-infrared wavelengths (6 - 20 micron), where an advantageous contrast ratio between star and planet occurs. The baseline mission lasts 5 years and consists of approximately 200 individual target stars. Among these, 25 to 50 planetary systems can be studied spectroscopically, searching for gases such as CO2, H2O, CH4 and O3. Many of the key technologies required for the constr...

  16. THE McDONALD OBSERVATORY PLANET SEARCH: NEW LONG-PERIOD GIANT PLANETS AND TWO INTERACTING JUPITERS IN THE HD 155358 SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Paul; Endl, Michael; Cochran, William D.; MacQueen, Phillip J.; Brugamyer, Erik J.; Barnes, Stuart I.; Caldwell, Caroline [Department of Astronomy and McDonald Observatory, University of Texas at Austin, Austin, TX 78712 (United States); Wittenmyer, Robert A.; Horner, J. [Department of Astrophysics and Optics, School of Physics, University of New South Wales, Sydney NSW 2052 (Australia); Simon, Attila E., E-mail: paul@astro.as.utexas.edu [Konkoly Observatory of the Hungarian Academy of Sciences, P.O. Box 67, H-1525 Budapest (Hungary)

    2012-04-10

    We present high-precision radial velocity (RV) observations of four solar-type (F7-G5) stars-HD 79498, HD 155358, HD 197037, and HD 220773-taken as part of the McDonald Observatory Planet Search Program. For each of these stars, we see evidence of Keplerian motion caused by the presence of one or more gas giant planets in long-period orbits. We derive orbital parameters for each system and note the properties (composition, activity, etc.) of the host stars. While we have previously announced the two-gas-giant HD 155358 system, we now report a shorter period for planet c. This new period is consistent with the planets being trapped in mutual 2:1 mean-motion resonance. We therefore perform an in-depth stability analysis, placing additional constraints on the orbital parameters of the planets. These results demonstrate the excellent long-term RV stability of the spectrometers on both the Harlan J. Smith 2.7 m telescope and the Hobby-Eberly telescope.

  17. Searching for signatures of planet formation in stars with circumstellar debris discs

    CERN Document Server

    Maldonado, J; Villaver, E; Montesinos, B; Mora, A

    2015-01-01

    (Abridged) Tentative correlations between the presence of dusty debris discs and low-mass planets have been presented. In parallel, detailed chemical abundance studies have reported different trends between samples of planet and non-planet hosts. We determine in a homogeneous way the metallicity, and abundances of a sample of 251 stars including stars with known debris discs, with debris discs and planets, and only with planets. Stars with debris discs and planets have the same [Fe/H] behaviour as stars hosting planets, and they also show a similar -Tc trend. Different behaviour in the -Tc trend is found between the samples of stars without planets and the samples of planet hosts. In particular, when considering only refractory elements, negative slopes are shown in cool giant planet hosts, whilst positive ones are shown in stars hosting low-mass planets. Stars hosting exclusively close-in giant planets show higher metallicities and positive -Tc slope. A search for correlations between the -Tc slopes and the ...

  18. Searching for the signatures of terrestial planets in solar analogs

    CERN Document Server

    Hernandez, J I Gonzalez; Santos, N C; Sousa, S; Delgado-Mena, E; Neves, V; Udry, S

    2010-01-01

    We present a fully differential chemical abundance analysis using very high-resolution (R >~ 85,000) and very high signal-to-noise (S/N~800 on average) HARPS and UVES spectra of 7 solar twins and 95 solar analogs, 24 are planet hosts and 71 are stars without detected planets. The whole sample of solar analogs provide very accurate Galactic chemical evolution trends in the metalliciy range -0.3<[Fe/H]<0.5. Solar twins with and without planets show similar mean abundance ratios. We have also analysed a sub-sample of 28 solar analogs, 14 planet hosts and 14 stars without known planets, with spectra at S/N~850 on average, in the metallicity range 0.14<[Fe/H]<0.36 and find the same abundance pattern for both samples of stars with and without planets. This result does not depend on either the planet mass, from 7 Earth masses to 17.4 Jupiter masses, or the orbital period of the planets, from 3 to 4300 days. In addition, we have derived the slope of the abundance ratios as a function of the condensation t...

  19. Pursuing the planet-debris disk connection: Analysis of upper limits from the Anglo-Australian planet search

    Energy Technology Data Exchange (ETDEWEB)

    Wittenmyer, Robert A.; Marshall, Jonathan P., E-mail: rob@phys.unsw.edu.au [School of Physics, UNSW Australia, Sydney 2052 (Australia)

    2015-02-01

    Solid material in protoplanetary disks will suffer one of two fates after the epoch of planet formation; either being bound up into planetary bodies, or remaining in smaller planetesimals to be ground into dust. These end states are identified through detection of sub-stellar companions by periodic radial velocity (or transit) variations of the star, and excess emission at mid- and far-infrared wavelengths, respectively. Since the material that goes into producing the observable outcomes of planet formation is the same, we might expect these components to be related both to each other and their host star. Heretofore, our knowledge of planetary systems around other stars has been strongly limited by instrumental sensitivity. In this work, we combine observations at far-infrared wavelengths by IRAS, Spitzer, and Herschel with limits on planetary companions derived from non-detections in the 16 year Anglo-Australian Planet Search to clarify the architectures of these (potential) planetary systems and search for evidence of correlations between their constituent parts. We find no convincing evidence of such correlations, possibly owing to the dynamical history of the disk systems, or the greater distance of the planet-search targets. Our results place robust limits on the presence of Jupiter analogs which, in concert with the debris disk observations, provides insights on the small-body dynamics of these nearby systems.

  20. Worlds beyond our own the search for habitable planets

    CERN Document Server

    Sengupta, Sujan

    2015-01-01

    This is a book on planets: Solar system planets and dwarf planets. And planets outside our solar system – exoplanets. How did they form? What types of planets are there and what do they have in common? How do they differ? What do we know about their atmospheres – if they have one? What are the conditions for life and on which planets may they be met? And what’s the origin of life on Earth and how did it form? You will understand how rare the solar system, the Earth and hence life is. This is also a book on stars. The first and second generation of stars in the Universe. But in particular also on the link between planets and stars – brown dwarfs. Their atmospheric properties and similarities with giant exoplanets. All these fascinating questions will be answered in a non-technical manner. But those of you who want to know a bit more may look up the relevant mathematical relationships in appendices.

  1. Educated search for transiting habitable planets. Targetting M dwarfs with known transiting planets

    CERN Document Server

    Gillon, M; Demory, B -O; Seager, S; Deming, D

    2010-01-01

    Because the planets of a system form in a flattened disk, they are expected to share similar orbital inclinations at the end of their formation. The photometric monitoring of stars known to host a transiting planet could thus reveal the transits of one or more other planets. Depending on several parameters, significantly enhanced transit probability could be expected for habitable planets. This approach is especially interesting for M dwarfs because these stars have close-in habitable zones and because their small radii make possible the detection of terrestrial planets down to Mars size. We investigate the potential of this approach for the two M dwarfs known to host a transiting planet, GJ 436 and GJ 1214. Contrary to GJ 436, GJ 1214 reveals to be a very promising target for the considered approach. Assuming a distribution of orbital inclinations similar to our solar system, a habitable planet orbiting around GJ 1214 would have a mean transit probability of ~25%, much better than the probability of 1.5% exp...

  2. A search for circumbinary planets in CoRoT eclipsing binary light curves

    Directory of Open Access Journals (Sweden)

    Klagyivik Peter

    2015-01-01

    Full Text Available Several transiting circumbinary planets have been found in data of the Kepler mission [1–5]. Both CoRoT and Kepler have surveyed similar numbers of stars, and the photometric precision of CoRoT is sufficient that it could detect most of the known circumbinary planets; the main draw-back by CoRoT is the much shorter coverage. Still, there is a high chance that some circumbinary planets may be found in its sample of eclipsing binaries (hereafter EBs. Here we report on an ongoing search for circumbinary planets in the full CoRoT data set.

  3. The search for life on Earth and other planets.

    Science.gov (United States)

    Gross, Michael

    2012-04-10

    As the NASA rover Curiosity approaches Mars on its quest to look for signs of past or present life there and sophisticated instruments like the space telescopes Kepler and CoRoT keep discovering additional, more Earth-like planets orbiting distant stars, science faces the question of how to spot life on other planets. Even here on Earth biotopes remain to be discovered and explored.

  4. SEARCHING FOR THE SIGNATURES OF TERRESTRIAL PLANETS IN SOLAR ANALOGS

    OpenAIRE

    Hernandez, J. I. Gonzalez; Israelian, G.; Santos,N.C.; Sousa, S.; Delgado-Mena, E.; Neves, V.; Udry, S.

    2010-01-01

    We present a fully differential chemical abundance analysis using very high-resolution (R >~ 85,000) and very high signal-to-noise (S/N~800 on average) HARPS and UVES spectra of 7 solar twins and 95 solar analogs, 24 are planet hosts and 71 are stars without detected planets. The whole sample of solar analogs provide very accurate Galactic chemical evolution trends in the metalliciy range -0.3

  5. Red Optical Planet Survey: A radial velocity search for low mass M dwarf planets

    Science.gov (United States)

    Barnes, J. R.; Jenkins, J. S.; Jones, H. R. A.; Rojo, P.; Arriagada, P.; Jordán, A.; Minniti, D.; Tuomi, M.; Jeffers, S. V.; Pinfield, D.

    2013-04-01

    We present radial velocity results from our Red Optical Planet Survey (ROPS), aimed at detecting low-mass planets orbiting mid-late M dwarfs. The ˜10 ms-1 precision achieved over 2 consecutive nights with the MIKE spectrograph at Magellan Clay is also found on week long timescales with UVES at VLT. Since we find that UVES is expected to attain photon limited precision of order 2 ms-1 using our novel deconvolution technique, we are limited only by the (≤10 ms-1) stability of atmospheric lines. Rocky planet frequencies of η⊕ = 0.3-0.7 lead us to expect high planet yields, enabling determination of η⊕ for the uncharted mid-late M dwarfs with modest surveys.

  6. Red Optical Planet Survey: A radial velocity search for low mass M dwarf planets

    Directory of Open Access Journals (Sweden)

    Minniti D.

    2013-04-01

    Full Text Available We present radial velocity results from our Red Optical Planet Survey (ROPS, aimed at detecting low-mass planets orbiting mid-late M dwarfs. The ∼10 ms−1 precision achieved over 2 consecutive nights with the MIKE spectrograph at Magellan Clay is also found on week long timescales with UVES at VLT. Since we find that UVES is expected to attain photon limited precision of order 2 ms−1 using our novel deconvolution technique, we are limited only by the (≤10 ms−1 stability of atmospheric lines. Rocky planet frequencies of η⊕ = 0.3−0.7 lead us to expect high planet yields, enabling determination of η⊕ for the uncharted mid-late M dwarfs with modest surveys.

  7. Pan-Planets: Searching for hot Jupiters around cool dwarfs

    CERN Document Server

    Obermeier, C; Saglia, R P; Henning, Th; Bender, R; Kodric, M; Deacon, N; Riffeser, A; Burgett, W; Chambers, K C; Draper, P W; Flewelling, H; Hodapp, K W; Kaiser, N; Kudritzki, R -P; Magnier, E A; Metcalfe, N; Price, P A; Sweeney, W; Wainscoat, R J; Waters, C

    2015-01-01

    The Pan-Planets survey observed an area of 42 sq deg. in the galactic disk for about 165 hours. The main scientific goal of the project is the detection of transiting planets around M dwarfs. We establish an efficient procedure for determining the stellar parameters $T_{eff}$ and log$g$ of all sources using a method based on SED fitting, utilizing a three-dimensional dust map and proper motion information. In this way we identify more than 60000 M dwarfs, which is by far the largest sample of low-mass stars observed in a transit survey to date. We present several planet candidates around M dwarfs and hotter stars that are currently being followed up. Using Monte-Carlo simulations we calculate the detection efficiency of the Pan-Planets survey for different stellar and planetary populations. We expect to find $3.0^{+3.3}_{-1.6}$ hot Jupiters around F, G, and K dwarfs with periods lower than 10 days based on the planet occurrence rates derived in previous surveys. For M dwarfs, the percentage of stars with a ho...

  8. Direct Imaging Search for Extrasolar Planets in the Pleiades

    Science.gov (United States)

    Yamamoto, Kodai; Matsuo, Taro; Shibai, Hiroshi; Itoh, Yoichi; Konishi, Mihokko; Sudo, Jun; Tanii, Ryoko; Fukagawa, Misato; Sumi, Takahiro; Kudo, Tomoyuki; Hashimoto, Jun; Kusakabe, Nobuhiko; Abe, Lyn; Brandner, Wolfgang; Brandt, Timothy D.; Carson, Joseph; Currie, Thayne; Egner, Sebastian E,; Feldt, Markus; Goto, Miwa; Grady, Carol; Guyon, Olivier; Hayano, Yutaka; McElwain, Mike; Serabyn, Eugene

    2013-01-01

    We carried out an imaging survey for extrasolar planets around stars in the Pleiades (125 Myr, 135 pc) in the H and K(sub S) bands using HiCIAO combined with adaptive optics, AO188, on the Subaru telescope. We found 13 companion candidates fainter than 14.5 mag in the H band around 9 stars. Five of these 13 were confirmed to be background stars by measurement of their proper motion. One was not found in the second epoch observation, and thus was not a background or companion object. One had multi-epoch images, but the precision of its proper motion was not sufficient to conclude whether it was a background object. Four other candidates are waiting for second-epoch observations to determine their proper motion. Finally, the remaining two were confirmed to be 60 M(sub J) brown dwarf companions orbiting around HD 23514 (G0) and HII 1348 (K5), respectively, as had been reported in previous studies. In our observations, the average detection limit for a point source was 20.3 mag in the H band beyond 1.'' 5 from the central star. On the basis of this detection limit, we calculated the detection efficiency to be 90% for a planet with 6 to 12 Jovian masses and a semi-major axis of 50–1000 AU. For this reason we extrapolated the distribution of the planet mass and the semi-major axis derived from radial velocity observations, and adopted the planet evolution model Baraffe et al. (2003, A&A, 402, 701). Since there was no detection of a planet, we estimated the frequency of such planets to be less than 17.9% (2 sigma) around one star of the Pleiades cluster.

  9. The impact of red noise in radial velocity planet searches: only three planets orbiting GJ 581?

    Science.gov (United States)

    Baluev, Roman V.

    2013-03-01

    We perform a detailed analysis of the latest HARPS and Keck radial velocity data for the planet-hosting red dwarf GJ 581, which attracted a lot of attention in recent time. We show that these data contain important correlated noise component (`red noise') with the correlation time-scale of the order of 10 d. This red noise imposes a lot of misleading effects while we work in the traditional white-noise model. To eliminate these misleading effects, we propose a maximum-likelihood algorithm equipped by an extended model of the noise structure. We treat the red noise as a Gaussian random process with an exponentially decaying correlation function. Using this method we prove that (i) planets b and c do exist in this system, since they can be independently detected in the HARPS and Keck data, and regardless of the assumed noise models; (ii) planet e can also be confirmed independently by both the data sets, although to reveal it in the Keck data it is mandatory to take the red noise into account; (iii) the recently announced putative planets f and g are likely just illusions of the red noise; (iv) the reality of the planet candidate GJ 581 d is questionable, because it cannot be detected from the Keck data, and its statistical significance in the HARPS data (as well as in the combined data set) drops to a marginal level of ˜2σ, when the red noise is taken into account. Therefore, the current data for GJ 581 really support the existence of no more than four (or maybe even only three) orbiting exoplanets. The planet candidate GJ 581 d requests serious observational verification.

  10. The HARPS search for southern extra-solar planets XL. Searching for Neptunes around metal-poor stars

    CERN Document Server

    Faria, J P; Figueira, P; Mortier, A; Dumusque, X; Boisse, I; Curto, G Lo; Lovis, C; Mayor, M; Melo, C; Pepe, F; Queloz, D; Santerne, A; Ségransan, D; Sousa, S G; Sozzetti, A; Udry, S

    2016-01-01

    Stellar metallicity -- as a probe of the metallicity of proto-planetary disks -- is an important ingredient for giant planet formation, likely through its effect on the timescales in which rocky/icy planet cores can form. Giant planets have been found to be more frequent around metal-rich stars, in agreement with predictions based on the core-accretion theory. In the metal-poor regime, however, the frequency of planets, especially low-mass planets, and how it depends on metallicity are still largely unknown. As part of a planet search programme focused on metal-poor stars, we study the targets from this survey that were observed with HARPS on more than 75 nights. The main goals are to assess the presence of low-mass planets and provide a first estimate of the frequency of Neptunes and super-Earths around metal-poor stars. We perform a systematic search for planetary companions, both by analysing the periodograms of the radial-velocities and by comparing, in a statistically-meaningful way, models with an incre...

  11. Search for giant planets in M 67. IV. Survey results

    Science.gov (United States)

    Brucalassi, A.; Koppenhoefer, J.; Saglia, R.; Pasquini, L.; Ruiz, M. T.; Bonifacio, P.; Bedin, L. R.; Libralato, M.; Biazzo, K.; Melo, C.; Lovis, C.; Randich, S.

    2017-07-01

    Context. We present the results of a seven-year-long radial velocity survey of a sample of 88 main-sequence and evolved stars to reveal signatures of Jupiter-mass planets in the solar-age and solar-metallicity open cluster M 67. Aims: We aim at studying the frequency of giant planets in this cluster with respect to the field stars. In addition, our sample is also ideal to perform a long-term study to compare the chemical composition of stars with and without giant planets in detail. Methods: We analyzed precise radial velocity (RV) measurements obtained with the HARPS spectrograph at the European Southern Observatory (La Silla), the SOPHIE spectrograph at the Observatoire de Haute-Provence (France), the HRS spectrograph at the Hobby Eberly Telescope (Texas), and the HARPS-N spectrograph at the Telescopio Nazionale Galileo (La Palma). Additional RV data come from the CORALIE spectrograph at the Euler Swiss Telescope (La Silla). We conducted Monte Carlo simulations to estimate the occurrence rate of giant planets in our radial velocity survey. We considered orbital periods between 1.0 day and 1000 days and planet masses between 0.2 MJ and 10.0 MJ. We used a measure of the observational detection efficiency to determine the frequency of planets for each star. Results: All the planets previously announced in this RV campaign with their properties are summarized here: 3 hot Jupiters around the main-sequence stars YBP1194, YBP1514, and YBP401, and 1 giant planet around the evolved star S364. Two additional planet candidates around the stars YBP778 and S978 are also analyzed in the present work. We discuss stars that exhibit large RV variability or trends individually. For 2 additional stars, long-term trends are compatible with new binary candidates or substellar objects, which increases the total number of binary candidates detected in our campaign to 14. Based on the Doppler-detected planets discovered in this survey, we find an occurrence of giant planets of 18

  12. Deep Space Detectives: Searching for Planets Suitable for Life

    Science.gov (United States)

    Pallant, Amy; Damelin, Daniel; Pryputniewicz, Sarah

    2013-01-01

    This article describes the High-Adventure Science curriculum unit "Is There Life in Space?" This free online investigation, developed by The Concord Consortium, helps students see how scientists use modern tools to locate planets around distant stars and explore the probability of finding extraterrestrial life. This innovative curriculum…

  13. Direct Imaging Search for Extrasolar Planets in the Pleiades

    NARCIS (Netherlands)

    Yamamoto, K.; et al., [Unknown; Thalmann, C.

    2013-01-01

    We carried out an imaging survey for extrasolar planets around stars in the Pleiades (125 Myr, 135 pc) in the H and KS bands using HiCIAO combined with adaptive optics, AO188, on the Subaru telescope. We found 13 companion candidates fainter than 14.5 mag in the H band around 9 stars. Five of these

  14. Deep Space Detectives: Searching for Planets Suitable for Life

    Science.gov (United States)

    Pallant, Amy; Damelin, Daniel; Pryputniewicz, Sarah

    2013-01-01

    This article describes the High-Adventure Science curriculum unit "Is There Life in Space?" This free online investigation, developed by The Concord Consortium, helps students see how scientists use modern tools to locate planets around distant stars and explore the probability of finding extraterrestrial life. This innovative curriculum…

  15. Pan-Planets: Searching for hot Jupiters around cool dwarfs

    Science.gov (United States)

    Obermeier, C.; Koppenhoefer, J.; Saglia, R. P.; Henning, Th.; Bender, R.; Kodric, M.; Deacon, N.; Riffeser, A.; Burgett, W.; Chambers, K. C.; Draper, P. W.; Flewelling, H.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Magnier, E. A.; Metcalfe, N.; Price, P. A.; Sweeney, W.; Wainscoat, R. J.; Waters, C.

    2016-03-01

    The Pan-Planets survey observed an area of 42 sq deg. in the galactic disk for about 165 h. The main scientific goal of the project is the detection of transiting planets around M dwarfs. We establish an efficient procedure for determining the stellar parameters Teff and log g of all sources using a method based on SED fitting, utilizing a three-dimensional dust map and proper motion information. In this way we identify more than 60 000 M dwarfs, which is by far the largest sample of low-mass stars observed in a transit survey to date. We present several planet candidates around M dwarfs and hotter stars that are currently being followed up. Using Monte Carlo simulations we calculate the detection efficiency of the Pan-Planets survey for different stellar and planetary populations. We expect to find 3.0+3.3-1.6 hot Jupiters around F, G, and K dwarfs with periods lower than 10 days based on the planet occurrence rates derived in previous surveys. For M dwarfs, the percentage of stars with a hot Jupiter is under debate. Theoretical models expect a lower occurrence rate than for larger main sequence stars. However, radial velocity surveys find upper limits of about 1% due to their small sample, while the Kepler survey finds a occurrence rate that we estimate to be at least 0.17b(+0.67-0.04) %, making it even higher than the determined fraction from OGLE-III for F, G and K stellar types, 0.14 (+0.15-0.076) %. With the large sample size of Pan-Planets, we are able to determine an occurrence rate of 0.11 (+0.37-0.02) % in case one of our candidates turns out to be a real detection. If, however, none of our candidates turn out to be true planets, we are able to put an upper limit of 0.34% with a 95% confidence on the hot Jupiter occurrence rate of M dwarfs. This limit is a significant improvement over previous estimates where the lowest limit published so far is 1.1% found in the WFCAM Transit Survey. Therefore we cannot yet confirm the theoretical prediction of a lower

  16. The SOPHIE search for northern extrasolar planets. IV. Massive companions in the planet-brown dwarf boundary

    Science.gov (United States)

    Díaz, R. F.; Santerne, A.; Sahlmann, J.; Hébrard, G.; Eggenberger, A.; Santos, N. C.; Moutou, C.; Arnold, L.; Boisse, I.; Bonfils, X.; Bouchy, F.; Delfosse, X.; Desort, M.; Ehrenreich, D.; Forveille, T.; Lagrange, A.-M.; Lovis, C.; Pepe, F.; Perrier, C.; Queloz, D.; Ségransan, D.; Udry, S.; Vidal-Madjar, A.

    2012-02-01

    Context. The mass domain where massive extrasolar planets and brown dwarfs lie is still poorly understood. Indeed, not even a clear dividing line between massive planets and brown dwarfs has been established yet. This is partly because these objects are very scarce in close orbits around solar-type stars, the so-called brown dwarf desert. Owing to this, it has proven difficult to set up a strong observational base with which to compare models and theories of formation and evolution. Aims: We search to increase the current sample of massive sub-stellar objects with precise orbital parameters, and to constrain the true mass of detected sub-stellar candidates. Methods: The initial identification of sub-stellar candidates was made using precise radial velocity measurements obtained with the SOPHIE spectrograph at the 1.93-m telescope of the Haute-Provence Observatory. Subsequent characterisation of these candidates, with the principal aim of identifying stellar companions in low-inclination orbits, was made by means of different spectroscopic diagnostics such as the measurement of the bisector velocity span and the study of the correlation mask effect. With this objective, we also employed astrometric data from the Hipparcos mission, and a novel method of simulating stellar cross-correlation functions. Results: Seven new objects with minimum masses between ~10 MJup and ~90 MJup are detected. Out of these, two are identified as low-mass stars in low-inclination orbits, and two others have masses below the theoretical deuterium-burning limit, and are therefore planetary candidates. The remaining three are brown dwarf candidates; the current upper limits for their the masses do not allow us to conclude on their nature. Additionally, we have improved the parameters of an already-known brown dwarf (HD 137510b), confirmed by astrometry. Based on observations collected with the SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS), France, by

  17. EXOTIME: searching for planets around pulsating subdwarf B stars

    CERN Document Server

    Schuh, Sonja; Lutz, Ronny; Loeptien, Bjoern; Green, Elizabeth M; Ostensen, Roy H; Leccia, Silvio; Kim, Seung-Lee; Fontaine, Gilles; Charpinet, Stephane; Francoeur, Myriam; Randall, Suzanna; Rodriguez-Lopez, Cristina; van Grootel, Valerie; Odell, Andrew P; Paparo, Margit; Bognar, Zsofia; Papics, Peter; Nagel, Thorsten; Beeck, Benjamin; Hundertmark, Markus; Stahn, Thorsten; Dreizler, Stefan; Hessman, Frederic V; Dall'Ora, Massimo; Mancini, Dario; Cortecchia, Fausto; Benatti, Serena; Claudi, Riccardo; Janulis, Rimvydas; 10.1007/s10509-010-0356-4

    2010-01-01

    In 2007, a companion with planetary mass was found around the pulsating subdwarf B star V391 Pegasi with the timing method, indicating that a previously undiscovered population of substellar companions to apparently single subdwarf B stars might exist. Following this serendipitous discovery, the EXOTIME (http://www.na.astro.it/~silvotti/exotime/) monitoring program has been set up to follow the pulsations of a number of selected rapidly pulsating subdwarf B stars on time-scales of several years with two immediate observational goals: 1) determine Pdot of the pulsational periods P 2) search for signatures of substellar companions in O-C residuals due to periodic light travel time variations, which would be tracking the central star's companion-induced wobble around the center of mass. These sets of data should therefore at the same time: on the one hand be useful to provide extra constraints for classical asteroseismological exercises from the Pdot (comparison with "local" evolutionary models), and on the othe...

  18. Development of highly sensitive monolithic interferometer for infrared planet search

    Directory of Open Access Journals (Sweden)

    Jiang P.

    2011-07-01

    Full Text Available We present the design, fabrication and testing of a highly sensitive monolithic interferometer for InfraRed Exoplanet Tracker (IR-ET. This interferometer is field-compensated, thermal-stable for working in the wavelength range between 0.8 and 1.35 μm. Two arms of the interferometer creates a fixed delay of 18.0 mm, which is optimized to have the best sensitivity for radial velocity measurements of slow-rotating M dwarfs for planet detection. IR-ET is aiming to reach 3–20 m/s Doppler precision for J<10 M dwarfs in less than 15 min exposures. We plan to conduct a planet survey around hundreds of nearby M dwarfs through collaborations with Astrophysical Research Consortium scientists in 2011–2014.

  19. The impact of red noise in radial velocity planet searches: Only three planets orbiting GJ581?

    CERN Document Server

    Baluev, Roman V

    2012-01-01

    We perform a detailed analysis of the latest HARPS and Keck radial velocity data for the planet-hosting red dwarf GJ581, which attracted a lot of attention in recent time. We show that these data contain important correlated noise component ("red noise") with the correlation timescale of the order of 10 days. This red noise imposes a lot of misleading effects while we work in the traditional white-noise model. To eliminate these misleading effects, we propose a maximum-likelihood algorithm equipped by an extended model of the noise structure. We treat the red noise as a Gaussian random process with exponentially decaying correlation function. Using this method we prove that: (i) planets b and c do exist in this system, since they can be independently detected in the HARPS and Keck data, and regardless of the assumed noise models; (ii) planet e can also be confirmed independently by the both datasets, although to reveal it in the Keck data it is mandatory to take the red noise into account; (iii) the recently ...

  20. A Search for Short-period Rocky Planets around WDs with the Cosmic Origins Spectrograph (COS)

    Science.gov (United States)

    Sandhaus, Phoebe H.; Debes, John H.; Ely, Justin; Hines, Dean C.; Bourque, Matthew

    2016-05-01

    The search for transiting habitable exoplanets has broadened to include several types of stars that are smaller than the Sun in an attempt to increase the observed transit depth and hence the atmospheric signal of the planet. Of all spectral types, white dwarfs (WDs) are the most favorable for this type of investigation. The fraction of WDs that possess close-in rocky planets is unknown, but several large angle stellar surveys have the photometric precision and cadence to discover at least one if they are common. Ultraviolet observations of WDs may allow for detection of molecular oxygen or ozone in the atmosphere of a terrestrial planet. We use archival Hubble Space Telescope data from the Cosmic Origins Spectrograph to search for transiting rocky planets around UV-bright WDs. In the process, we discovered unusual variability in the pulsating WD GD 133, which shows slow sinusoidal variations in the UV. While we detect no planets around our small sample of targets, we do place stringent limits on the possibility of transiting planets, down to sub-lunar radii. We also point out that non-transiting small planets in thermal equilibrium are detectable around hotter WDs through infrared excesses, and identify two candidates. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555.

  1. A Search for Rocky Planets in Close Orbits around White Dwarfs

    Science.gov (United States)

    Debes, John; Sandhaus, Phoebe; Ely, Justin

    2015-12-01

    The search for transiting habitable exoplanets has broadened to include several types of stars that are smaller than the Sun in order to increase the observed transit depth and hence the atmospheric signal of the planet. Of all current spectral types, white dwarfs are the most favorable for this type of investigation. The fraction of white dwarfs that possess close-in rocky planets is unknown, but several large angle surveys of stars have the photometric precision and cadence to discover at least one if they are common. Ultraviolet observations of white dwarfs may allow for detection of molecular oxygen or ozone in the atmosphere of a terrestrial planet. We use archival Hubble Space Telescope data from the Cosmic Origins Spectrograph to search for transiting rocky planets around UV-bright white dwarfs. In the process, we discovered unusual variability in the pulsating white dwarf GD~133, which shows slow sinusoidal variations in the UV. While we detect no planets around our small sample of targets, we do place stringent limits on the possibility of transiting planets, down to sub-lunar radii. We also point out that non-transiting small planets in thermal equilibrium are detectable around hotter white dwarfs through infrared excesses, and identify two candidates.

  2. Darwin--a mission to detect and search for life on extrasolar planets.

    Science.gov (United States)

    Cockell, C S; Léger, A; Fridlund, M; Herbst, T M; Kaltenegger, L; Absil, O; Beichman, C; Benz, W; Blanc, M; Brack, A; Chelli, A; Colangeli, L; Cottin, H; Coudé du Foresto, F; Danchi, W C; Defrère, D; den Herder, J-W; Eiroa, C; Greaves, J; Henning, T; Johnston, K J; Jones, H; Labadie, L; Lammer, H; Launhardt, R; Lawson, P; Lay, O P; LeDuigou, J-M; Liseau, R; Malbet, F; Martin, S R; Mawet, D; Mourard, D; Moutou, C; Mugnier, L M; Ollivier, M; Paresce, F; Quirrenbach, A; Rabbia, Y D; Raven, J A; Rottgering, H J A; Rouan, D; Santos, N C; Selsis, F; Serabyn, E; Shibai, H; Tamura, M; Thiébaut, E; Westall, F; White, G J

    2009-01-01

    The discovery of extrasolar planets is one of the greatest achievements of modern astronomy. The detection of planets that vary widely in mass demonstrates that extrasolar planets of low mass exist. In this paper, we describe a mission, called Darwin, whose primary goal is the search for, and characterization of, terrestrial extrasolar planets and the search for life. Accomplishing the mission objectives will require collaborative science across disciplines, including astrophysics, planetary sciences, chemistry, and microbiology. Darwin is designed to detect rocky planets similar to Earth and perform spectroscopic analysis at mid-infrared wavelengths (6-20 mum), where an advantageous contrast ratio between star and planet occurs. The baseline mission is projected to last 5 years and consists of approximately 200 individual target stars. Among these, 25-50 planetary systems can be studied spectroscopically, which will include the search for gases such as CO(2), H(2)O, CH(4), and O(3). Many of the key technologies required for the construction of Darwin have already been demonstrated, and the remainder are estimated to be mature in the near future. Darwin is a mission that will ignite intense interest in both the research community and the wider public.

  3. The Search for other Earths: limits on the giant planet orbits that allow habitable terrestrial planets to form

    OpenAIRE

    Raymond, Sean N.

    2006-01-01

    Gas giant planets are far easier than terrestrial planets to detect around other stars, and are thought to form much more quickly than terrestrial planets. Thus, in systems with giant planets, the late stages of terrestrial planet formation are strongly affected by the giant planets' dynamical presence. Observations of giant planet orbits may therefore constrain the systems that can harbor potentially habitable, Earth-like planets. We present results of 460 N-body simulations of terrestrial a...

  4. A Search for Additional Planets in the NASA EPOXI Observations of the Exoplanet System GJ 436

    CERN Document Server

    Ballard, Sarah; Charbonneau, David; Deming, Drake; Holman, Matthew J; Fabrycky, Daniel; A'Hearn, Michael F; Wellnitz, Dennis D; Barry, Richard K; Kuchner, Marc J; Livengood, Timothy A; Hewagama, Tilak; Sunshine, Jessica M; Hampton, Don L; Lisse, Carey M; Seager, Sara; Veverka, Joseph F

    2009-01-01

    We present time series photometry of the M dwarf transiting exoplanet system GJ 436 obtained with the the EPOCh (Extrasolar Planet Observation and Characterization) component of the NASA EPOXI mission. We conduct a search of the high-precision time series for additional planets around GJ 436, which could be revealed either directly through their photometric transits, or indirectly through the variations these second planets induce on the transits of the previously known planet. In the case of GJ 436, the presence of a second planet is perhaps indicated by the residual orbital eccentricity of the known hot Neptune companion. We find no candidate transits with significance higher than our detection limit. From Monte Carlo tests of the time series, we rule out transiting planets larger than 1.0 R_Earth interior to GJ 436b with 95% confidence. Assuming coplanarity of additional planets with the orbit of GJ 436b, we cannot expect that putative planets with orbital periods longer than about 3.4 days will transit. H...

  5. The Solar Neighborhood. 34. A Search for Planets Orbiting Nearby M Dwarfs Using Astrometry

    Science.gov (United States)

    2014-11-01

    REPORT DATE NOV 2014 2. REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE The Solar Neighborhood, XXXIV. A Search...data. The lower panel indicates that for the best case targets (stars at close distances and of low mass). We are most sensitive to Jovian- type planets...THE SOLAR NEIGHBORHOOD. XXXIV. A SEARCH FOR PLANETS ORBITING NEARBY M DWARFS USING ASTROMETRY John C. Lurie1,7, Todd J. Henry2,7, Wei-Chun Jao3,7

  6. The CRIRES Search for Planets Around the Lowest-Mass Stars. II. No Giant Planet Orbiting VB10

    CERN Document Server

    Bean, Jacob L; Hartman, Henrik; Nilsson, Hampus; Reiners, Ansgar; Dreizler, Stefan; Henry, Todd J; Wiedemann, Guenter

    2009-01-01

    We present radial velocities of the very low-mass star VB10 obtained over a time span of 0.61 yr as part of an ongoing search for planets around stars at the end of the main sequence. The radial velocities were measured from high-resolution near-infrared spectra obtained using the CRIRES instrument on the VLT with an ammonia gas cell. The typical internal precision of the measurements is 10 m/s. These data do not exhibit significant variability and are essentially constant at a level consistent with the measurement uncertainties. Therefore, we do not detect the radial velocity variations of VB10 expected due to the presence of an orbiting giant planet similar to that recently proposed by Pravdo and Shaklan based on apparent astrometric perturbations. In addition, we do not confirm the ~1 km/s radial velocity variability of the star tentatively detected by Zapatero Osorio and colleagues with lower precision measurements. Our measurements rule out planets with M > 3 M_Jup and the orbital period and inclination ...

  7. A Search for Rocky Planets in Close Orbits around White Dwarfs with COS

    Science.gov (United States)

    Sandhaus, Phoebe; Debes, John H.; Ely, Justin; Hines, Dean C.

    2016-01-01

    The search for transiting habitable exoplanets has broadened to include several types of stars that are smaller than the Sun in order to increase the observed transit depth and hence the atmospheric signal of the planet. Of all current spectral types, white dwarfs are the most favorable for this type of investigation. The fraction of white dwarfs that possess close-in rocky planets is unknown, but several large angle surveys of stars have the photometric precision and cadence to discover at least one if they are common. Ultraviolet observations of white dwarfs may allow for detection of molecular oxygen or ozone in the atmosphere of a terrestrial planet. We use archival Hubble Space Telescope data from the Cosmic Origins Spectrograph to search for transiting rocky planets around UV-bright white dwarfs. In the process, we discovered unusual variability in the pulsating white dwarf GD~133, which shows slow sinusoidal variations in the UV. While we detect no planets around our small sample of targets, we do place stringent limits on the possibility of transiting planets, down to sub-lunar radii.

  8. Planets in Spin-Orbit Misalignment and the Search for Stellar Companions

    CERN Document Server

    Addison, Brett C; Wright, Duncan J; Salter, Graeme; Bayliss, Daniel; Zhou, George

    2014-01-01

    The discovery of giant planets orbiting close to their host stars was one of the most unexpected results of early exoplanetary science. Astronomers have since found that a significant fraction of these 'Hot Jupiters' move on orbits substantially misaligned with the rotation axis of their host star. We recently reported the measurement of the spin-orbit misalignment for WASP-79b by using data from the 3.9 m Anglo-Australian Telescope. Contemporary models of planetary formation produce planets on nearly coplanar orbits with respect to their host star's equator. We discuss the mechanisms which could drive planets into spin-orbit misalignment. The most commonly proposed being the Kozai mechanism, which requires the presence of a distant, massive companion to the star-planet system. We therefore describe a volume-limited direct-imaging survey of Hot Jupiter systems with measured spin-orbit angles, to search for the presence of stellar companions and test the Kozai hypothesis.

  9. The Pan-Pacific Planet Search III: Five companions orbiting giant stars

    CERN Document Server

    Wittenmyer, R A; Wang, L; Bergmann, C; Salter, G S; Tinney, C G; Johnson, John Asher

    2015-01-01

    We report a new giant planet orbiting the K giant HD 155233, as well as four stellar-mass companions from the Pan-Pacific Planet Search, a southern hemisphere radial velocity survey for planets orbiting nearby giants and subgiants. We also present updated velocities and a refined orbit for HD 47205b (7 CMa b), the first planet discovered by this survey. HD 155233b has a period of 885$\\pm$63 days, eccentricity e=0.03$\\pm$0.20, and m sin i=2.0$\\pm$0.5 M_jup. The stellar-mass companions range in m sin i from 0.066 M_sun to 0.33 M_sun. Whilst HD 104358B falls slightly below the traditional 0.08 M_sun hydrogen-burning mass limit, and is hence a brown dwarf candidate, we estimate only a 50% a priori probability of a truly substellar mass.

  10. The Anglo-Australian Planet Search XXIV: The Frequency of Jupiter Analogs

    CERN Document Server

    Wittenmyer, Robert A; Tinney, C G; Horner, Jonathan; Carter, B D; Wright, D J; Jones, H R A; Bailey, J; O'Toole, Simon J

    2016-01-01

    We present updated simulations of the detectability of Jupiter analogs by the 17-year Anglo-Australian Planet Search. The occurrence rate of Jupiter-like planets that have remained near their formation locations beyond the ice line is a critical datum necessary to constrain the details of planet formation. It is also vital in our quest to fully understand how common (or rare) planetary systems like our own are in the Galaxy. From a sample of 202 solar-type stars, and correcting for imperfect detectability on a star-by-star basis, we derive a frequency of $6.2^{+2.8}_{-1.6}$% for giant planets in orbits from 3-7 AU. When a consistent definition of "Jupiter analog" is used, our results are in agreement with those from other legacy radial velocity surveys.

  11. The SOPHIE search for northern extrasolar planets. X. Detection and characterization of giant planets by the dozen

    Science.gov (United States)

    Hébrard, G.; Arnold, L.; Forveille, T.; Correia, A. C. M.; Laskar, J.; Bonfils, X.; Boisse, I.; Díaz, R. F.; Hagelberg, J.; Sahlmann, J.; Santos, N. C.; Astudillo-Defru, N.; Borgniet, S.; Bouchy, F.; Bourrier, V.; Courcol, B.; Delfosse, X.; Deleuil, M.; Demangeon, O.; Ehrenreich, D.; Gregorio, J.; Jovanovic, N.; Labrevoir, O.; Lagrange, A.-M.; Lovis, C.; Lozi, J.; Moutou, C.; Montagnier, G.; Pepe, F.; Rey, J.; Santerne, A.; Ségransan, D.; Udry, S.; Vanhuysse, M.; Vigan, A.; Wilson, P. A.

    2016-04-01

    We present new radial velocity measurements of eight stars that were secured with the spectrograph SOPHIE at the 193 cm telescope of the Haute-Provence Observatory. The measurements allow detecting and characterizing new giant extrasolar planets. The host stars are dwarfs of spectral types between F5 and K0 and magnitudes of between 6.7 and 9.6; the planets have minimum masses Mp sin i of between 0.4 to 3.8 MJup and orbitalperiods of several days to several months. The data allow only single planets to be discovered around the first six stars (HD 143105, HIP 109600, HD 35759, HIP 109384, HD 220842, and HD 12484), but one of them shows the signature of an additional substellar companion in the system. The seventh star, HIP 65407, allows the discovery of two giant planets that orbit just outside the 12:5 resonance in weak mutual interaction. The last star, HD 141399, was already known to host a four-planet system; our additional data and analyses allow new constraints to be set on it. We present Keplerian orbits of all systems, together with dynamical analyses of the two multi-planet systems. HD 143105 is one of the brightest stars known to host a hot Jupiter, which could allow numerous follow-up studies to be conducted even though this is not a transiting system. The giant planets HIP 109600b, HIP 109384b, and HD 141399c are located in the habitable zone of their host star. Based on observations collected with the SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS), France, by the SOPHIE Consortium (programs 07A.PNP.CONS to 15A.PNP.CONS).Full version of the SOPHIE measurements (Table 1) is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/588/A145

  12. Scientists Plot Search For Earth--Like Planets

    Institute of Scientific and Technical Information of China (English)

    Andrew; Quinn; 金月芹

    1999-01-01

    1999年5月22日清晨,在Internet上读到此文,兴奋异常。遥望那无垠的、群星闪烁的夜空,人类很早就在思考:Are we alone in the universe?许多科幻小说中描写的外星人,更点燃了人类的想象。人们在无法解开金字塔的建造之谜时,仰望太空,猜测那是外星人在地球上留下的杰作;人们在惊叹UFO的神秘行踪时,也翘首天际,设想那是外星人在向我们暗递的“秋波”!今天,人类的科技终于驶入了一个新时代,能够更精确更清晰更自信地去探求茫茫宇宙里的奥秘。这篇报道的第一句就足以让我们欣喜: Somewhere,in a star system porhaps not so far away,lies a″ pale bluedot″which could be a planet much like Earth. 在这个淡蓝色的小点(pale blue dot)上也许就生活着人类的邻居。美国的一群科学家们上周就聚首在位于加州的NASA(国家航空和航天局)researchcenter,这次科学聚会就被称为The″Pale Blue Dot″Conference!再过10年,一个名为Terrestrial Planet Finder的宇宙望远镜将投入使用,届时,它将提供比目前的哈勃望远镜清晰100倍的图象。 美国亚利桑那州的的一位天文学家这样断言: Life on earth is by no means the only kind of life that can exist. 在即将过去的20世纪,人类登上了月球,失望地发现,那里除了环形山?

  13. Direct Imaging Search for Extrasolar Planets in the Pleiades

    CERN Document Server

    Yamamoto, Kodai; Shibai, Hiroshi; Itoh, Yoichi; Konishi, Mihoko; Sudo, Jun; Tanii, Ryoko; Fukagawa, Misato; Sumi, Takahiro; Kudo, Tomoyuki; Hashimoto, Jun; Kusakabe, Nobuhiko; Abe, Lyu; Brandner, Wolfgang; Brandt, Timothy D; Carson, Joseph; Currie, Thayne; Egner, Sebastian E; Feldt, Markus; Goto, Miwa; Grady, Carol; Guyon, Olivier; Hayano, Yutaka; Hayashi, Masahiko; Hayashi, Saeko; Henning, Thomas; Hodapp, Klaus; Ishii, Miki; Iye, Masanori; Janson, Markus; Kandori, Ryo; Knapp, Gillian R; Kuzuhara, Masayuki; Kwon, Jungmi; McElwain, Mike; Miyama, Shoken; Morino, Jun-Ichi; Moro-Martin, Amaya; Nishikawa, June; Nishimura, Tetsuo; Pyo, Tae-Soo; Serabyn, Eugene; Suto, Hiroshi; Suzuki, Ryuji; Takami, Michihiro; Takato, Naruhisa; Terada, Hiroshi; Thalmann, Christian; Tomono, Daigo; Turner, Edwin L; Wisniewski, John; Watanabe, Makoto; Yamada, Toru; Takami, Hideki; Usuda, Tomonori; Tamura, Motohide

    2013-01-01

    We carried out an imaging survey for extrasolar planets around stars in the Pleiades (125 Myr, 135 pc) in the $H$ and $K_{S}$ bands using HiCIAO combined with the adaptive optics, AO188, on the Subaru telescope. We found 13 companion candidates fainter than 14.5 mag in the $H$ band around 9 stars. Five of these 13 were confirmed to be background stars by measurement of their proper motion. One was not found in the second epoch observation, and thus was not a background or companion object. One had multi-epoch image, but the precision of its proper motion was not sufficient to conclude whether it was background object. Four other candidates are waiting for second epoch observations to determine their proper motion. Finally, the remaining 2 were confirmed to be 60 $M_{J}$ brown dwarf companions orbiting around HD 23514 (G0) and HII 1348 (K5) respectively, as had been reported in previous studies. In our observations, the average detection limit for a point source was 20.3 mag in the $H$ band beyond 1''.5 from t...

  14. A Search for short-period Rocky Planets around WDs with the Cosmic Origins Spectrograph (COS)

    CERN Document Server

    Sandhaus, P H; Ely, J; Hines, D C; Bourque, M

    2016-01-01

    The search for transiting habitable exoplanets has broadened to include several types of stars that are smaller than the Sun in an attempt to increase the observed transit depth and hence the atmospheric signal of the planet. Of all spectral types, white dwarfs are the most favorable for this type of investigation. The fraction of white dwarfs that possess close-in rocky planets is unknown, but several large angle stellar surveys have the photometric precision and cadence to discover at least one if they are common. Ultraviolet observations of white dwarfs may allow for detection of molecular oxygen or ozone in the atmosphere of a terrestrial planet. We use archival Hubble Space Telescope data from the Cosmic Origins Spectrograph to search for transiting rocky planets around UV-bright white dwarfs. In the process, we discovered unusual variability in the pulsating white dwarf GD 133, which shows slow sinusoidal variations in the UV. While we detect no planets around our small sample of targets, we do place st...

  15. Types of Information Expected from a Photometric Search for Extra-Solar Planets

    Science.gov (United States)

    Borucki, William; Koch, David; Bell, James, III; Cuzzi, Jeffrey N. (Technical Monitor)

    1994-01-01

    The current theory postulates that planets are a consequence of the formation of stars from viscous accretion disks. Condensation from the hotter, inner portion of the accretion disk favors the formation of small rocky planets in the inner portion and the formation of gas giants in the cuter, cooler part. Consequently, terrestrial-type planets in inner orbits must be commonplace (Wetheril 1991). From the geometry of the situation (Borucki and Summers 1984), it can be shown that 1% of those planetary systems that resemble our solar system should show transits for Earth-sized (or larger) planets. Thus a photometric satellite that uses a wide field of view telescope and a large CCD array to simultaneously monitor 5000 target stars should detect 50 planetary systems. To verify that regularly recurring transits are occurring rather than statistical fluctuations of the stellar flux, demands observations that extend over several orbital periods so that the constancy of the orbital period, signal amplitude, and duration can be measured. Therefore, to examine the region from Mercury's orbit to that of the Earth requires a duration of three years whereas a search out to the orbit of mars requires about six years. The results of the observations should provide estimates of the distributions of planetary size and orbital radius, and the frequency of planetary systems that have Earth-sized planets in inner orbits. Because approximately one half of the star systems observed will be binary systems, the frequency of planetary systems orbit ' ing either one or both of the stars can also be determined. Furthermore, the complexity of the photometric signature of a planet transiting a pair of stars provides enough information to estimate the eccentricities of the planetary orbits. In summary, the statistical evidence from a photometric search of solar-like stars should be able to either confirm or deny the applicability of the current theory of planet formation and provide new

  16. Searching for Planet Nine with Coadded WISE and NEOWISE-Reactivation Images

    CERN Document Server

    Meisner, Aaron M; Nugent, Peter E; Schlegel, David J; Kenyon, Scott J; Schlafly, Edward F; Dawson, Kyle S

    2016-01-01

    A distant, as yet unseen ninth planet has been invoked to explain various observations of the outer solar system. While such a 'Planet Nine', if it exists, is most likely to be discovered via reflected light in the optical, it may emit much more strongly at 3$-$5$\\mu$m than simple blackbody predictions would suggest, depending on its atmospheric properties (Fortney et al. 2016). As a result, Planet Nine may be detectable at 3.4$\\mu$m with WISE, but single exposures are too shallow except at relatively small distances ($d_9 \\lesssim 430$ AU). We develop a method to search for Planet Nine far beyond the W1 single-exposure sensitivity, to distances as large as 800 AU, using inertial coadds of W1 exposures binned into $\\sim$1 day intervals. We apply our methodology to $\\sim$2000 square degrees of sky identified by Holman & Payne (2016) as a potentially likely Planet Nine location, based on the Fienga et al. (2016) Cassini ranging analysis. We do not detect a plausible Planet Nine candidate, but are able to de...

  17. Searching for Planet Nine with Coadded WISE and NEOWISE-Reactivation Images

    Science.gov (United States)

    Meisner, Aaron M.; Bromley, Benjamin C.; Nugent, Peter E.; Schlegel, David J.; Kenyon, Scott J.; Schlafly, Edward F.; Dawson, Kyle S.

    2017-02-01

    A distant, as yet unseen ninth planet has been invoked to explain various observations of the outer solar system. While such a “Planet Nine,” if it exists, is most likely to be discovered via reflected light in the optical, it may emit much more strongly at 3‑5 μm than simple blackbody predictions would suggest, depending on its atmospheric properties. As a result, Planet Nine may be detectable at 3.4 μm with the Wide-field Infrared Survey Explorer, but single exposures are too shallow except at relatively small distances ({d}9≲ 430 au). We develop a method to search for Planet Nine far beyond the W1 single-exposure sensitivity, to distances as large as 800 au, using inertial coadds of W1 exposures binned into ∼1 day intervals. We apply our methodology to a ∼2000 square degree testbed sky region which overlaps a southern segment of Planet Nine’s anticipated orbital path. We do not detect a plausible Planet Nine candidate, but are able to derive a detailed completeness curve, ruling out its presence within the parameter space searched at W1 < 16.66 (90% completeness). Our method uses all publicly available W1 imaging, spanning 2010 January to 2015 December, and will become more sensitive with future NEOWISE-Reactivation releases of additional W1 exposures. We anticipate that our method will be applicable to the entire high Galactic latitude sky, and we will extend our search to that full footprint in the near future.

  18. Search for a habitable terrestrial planet transiting the nearby red dwarf GJ 1214

    CERN Document Server

    Gillon, M; Madhusudhan, N; Deming, D; Seager, S; Knutson, H A; Lanotte, A; Bonfils, X; Desert, J -M; Delrez, L; Jehin, E; Fraine, J D; Magain, P; Triaud, A H M J

    2013-01-01

    High-precision eclipse spectrophotometry of transiting terrestrial exoplanets represents a promising path for the first atmospheric characterizations of habitable worlds and the search for life outside our solar system. The detection of terrestrial planets transiting nearby late-type M-dwarfs could make this approach applicable within the next decade, with near-to-come general facilities. In this context, we previously identified GJ 1214 as a high-priority target for a transit search, as the transit probability of a habitable planet orbiting this nearby M4.5 dwarf would be significantly enhanced by the transiting nature of GJ 1214 b, the super-Earth already known to orbit the star. Basing on this observation, we have set-up an ambitious high-precision photometric monitoring of GJ 1214 with the Spitzer Space Telescope to probe its entire habitable zone in search of a transiting planet as small as Mars. We present here the results of this transit search. Unfortunately, we did not detect any second transiting pl...

  19. On the Search For Transits of the Planets Orbiting Gl 876

    CERN Document Server

    Shankland, P D; Laughlin, G; Blank, D L; Price, A; Gary, B; Bissinger, R; Ringwald, F; White, G; Henry, G W; McGee, P; Wolf, A S; Carter, B; Lee, S; Biggs, J; Monard, B; Ashley, M C B

    2006-01-01

    We report the results of a globally coordinated photometric campaign to search for transits by the P ~ 30 d and P ~ 60 d outer planets of the 3-planet system orbiting the nearby M-dwarf Gl 876. These two planets experience strong mutual perturbations, which necessitate use of a dynamical (four-body) model to compute transit ephemerides for the system. Our photometric data have been collected from published archival sources, as well as from our photometric campaigns that were targeted to specific transit predictions. Our analysis indicates that transits by planet "c" (P ~ 30 d) do not currently occur, in concordance with the best-fit i = 50 degree co-planar configuration obtained by dynamical fits to the most recent radial velocity data for the system. Transits by planet "b" (P ~ 60 d) are not entirely ruled out by our observations, but our data indicate that it is very unlikely that they occur. Our experience with the Gl 876 system suggests that a distributed ground-based network of small telescopes can be us...

  20. A systematic search for transiting planets in the K2 data

    CERN Document Server

    Foreman-Mackey, Daniel; Hogg, David W; Morton, Timothy D; Wang, Dun; Schölkopf, Bernhard

    2015-01-01

    Photometry of stars from the K2 extension of NASA's Kepler mission is afflicted by systematic effects caused by small (few-pixel) drifts in the telescope pointing and other spacecraft issues. We present a method for searching K2 light curves for evidence of exoplanets by simultaneously fitting for these systematics and the transit signals of interest. This method is more computationally expensive than standard search algorithms but we demonstrate that it can be efficiently implemented and used to discover transit signals. We apply this method to the full Campaign 1 dataset and report a list of 36 planet candidates transiting 31 stars, along with an analysis of the pipeline performance and detection efficiency based on artificial signal injections and recoveries. For all planet candidates, we present posterior distributions on the properties of each system based strictly on the transit observables.

  1. Two New Long-Period Giant Planets from the McDonald Observatory Planet Search and Two Stars with Long-Period Radial Velocity Signals Related to Stellar Activity Cycles

    CERN Document Server

    Endl, Michael; Cochran, William D; MacQueen, Phillip J; Robertson, Paul; Meschiari, Stefano; Ramirez, Ivan; Shetrone, Matthew; Gullikson, Kevin; Johnson, Marshall C; Wittenmyer, Robert; Horner, Jonathan; Ciardi, David R; Horch, Elliott; Simon, Attila E; Howell, Steve B; Everett, Mark; Caldwell, Caroline; Castanheira, Barbara G

    2015-01-01

    We report the detection of two new long-period giant planets orbiting the stars HD 95872 and HD 162004 (psi1 Draconis B) by the McDonald Observatory planet search. The planet HD 95872b has a minimum mass of 4.6 M_Jup and an orbital semi-major axis of 5.2 AU. The giant planet psi1 Dra Bb has a minimum mass of 1.5 M_Jup and an orbital semi-major axis of 4.4 AU. Both of these planets qualify as Jupiter analogs. These results are based on over one and a half decades of precise radial velocity measurements collected by our program using the McDonald Observatory Tull Coude spectrograph at the 2.7 m Harlan J. Smith telescope. In the case of psi1 Draconis B we also detect a long-term non-linear trend in our data that indicates the presence of an additional giant planet, similar to the Jupiter-Saturn pair. The primary of the binary star system, psi1 Dra A, exhibits a very large amplitude radial velocity variation due to another stellar companion. We detect this additional member using speckle imaging. We also report t...

  2. Search for 150 MHz radio emission from extrasolar planets in the TIFR GMRT Sky Survey

    Science.gov (United States)

    Sirothia, S. K.; Lecavelier des Etangs, A.; Gopal-Krishna; Kantharia, N. G.; Ishwar-Chandra, C. H.

    2014-02-01

    The ongoing radio continuum TIFR GMRT Sky Survey (TGSS) using the Giant Metrewave Radio Telescope (GMRT) at 150 MHz offers an unprecedented opportunity to undertake a fairly deep search for low-frequency radio emission from nearby extrasolar planets. Currently TGSS images are available for a little over a steradian, encompassing 175 confirmed exoplanetary systems. We have searched for their radio counterparts in the TGSS (150 MHz), supplemented with a search in the NRAO VLA Sky Survey (NVSS) and the VLA FIRST survey at 1.4 GHz. For 171 planetary systems, we find no evidence of radio emission in the TGSS maps, placing a 3σ upper limit between 8.7 mJy and 136 mJy (median ~24.8 mJy) at 150 MHz. These non-detections include the 55 Cnc system for which we place a 3σ upper limit of 28 mJy at 150 MHz. Nonetheless, for four of the extrasolar planetary systems, we find TGSS radio sources coinciding with or located very close to their coordinates. One of these is 61 Vir: for this system a large radio flux density was predicted in the scenario involving magnetosphere-ionosphere coupling and rotation-induced radio emission. We also found 150 MHz emissions toward HD 86226 and HD 164509, where strong radio emission can be produced by the presence of a massive satellite orbiting a rapidly rotating planet. We also detected 150 MHz emission within a synthesized beam from 1RXS1609 b, a pre-main-sequence star harboring a ~14 Jupiter mass planet (or a brown dwarf). With a bright X-ray-UV star and a high mass, the planet 1RXS1609 b presents the best characteristics for rotation-induced emissions with high radio power. Deeper high-resolution observations toward these planetary systems are needed to discriminate between the possibilities of background radio-source and radio-loud planets. At 1.4 GHz, radio emission toward the planet-harboring pulsar PSR B1620-26 is detected in the NVSS. Emissions at 1.4 GHz are also detected toward the very-hot-Jupiter WASP-77A b (in the FIRST survey

  3. Search and study of lightnings on planets of the Solar System

    Science.gov (United States)

    Zakharenko, V.; Konovalenko, A.; Kolyadin, V.; Zarka, P.; Grissmeier, J.-M.; Mylostna, K.; Litvinenko, G.; Sidorchuk, M.; Rucker, H.; Cecconi, B.; Coffre, A.; Denis, L.; Shevchenko, V.; Nikolaenko, V.; Fisher, G.

    2012-04-01

    Following the recent successful identification of lightning on Saturn recorded by ground-based radio telescope UTR-2 and spasecraft Cassini, we continued to study and search for electrostatic discharges on other planets of the Solar System. With the help of the receiving equipment with high frequency and time resolution the dispersion delay of short powerful discharges was fixed in the frequency band 16.5...33.0 MHz, that uniquely allows as to distinguish the lightnings and terrestrial broadband interference. We also defined other parameters of their radio emission. Uranus, Jupiter and Venus were selected as the following objects for searching. Observations were carried out and are currently under processing.

  4. Search for Close-in Planets around Evolved Stars with Phase-curve variations and Radial Velocity Measurements

    Science.gov (United States)

    Hirano, Teruyuki; Sato, Bun'ei; Masuda, Kento; Benomar, Othman Michel; Takeda, Yoichi; Omiya, Masashi; Harakawa, Hiroki

    2016-10-01

    Tidal interactions are a key process to understand the evolution history of close-in exoplanets. But tidals still have a large uncertainty in their prediction for the damping timescales of stellar obliquity and semi-major axis. We have worked on a search for transiting giant planets around evolved stars, for which few close-in planets were discovered. It has been reported that evolved stars lack close-in planets, which is often attributed to the tidal evolution and/or engulfment of close-in planets by the hosts. Meanwhile, Kepler has detected a certain fraction of transiting planet candidates around evolved stars. Confirming the planetary nature for these candidates is especially important since the comparison between the occurrence rates of close-in planets around main sequence stars and evolved stars provides a unique opportunity to discuss the final stage of close-in planets. With the aim of confirming KOI planet candidates around evolved stars, we measured precision radial velocities (RVs) for evolved stars with transiting planet candidates using Subaru/HDS. We also developed a new code which simultaneously models and fits the observed RVs and phase-curve variations in the Kepler data (e.g., transits, stellar ellipsoidal variations, and planet emission/reflected light). As a result of applying the global fit to KOI giants/subgiants, we confirmed two giant planets around evolved stars (Kepler-91 and KOI-1894), as well as revealed that KOI-977 is more likely a false positive.

  5. The Anglo-Australian Planet Search. XXIII. Two New Jupiter Analogs

    CERN Document Server

    Wittenmyer, Robert A; Tinney, C G; Butler, R P; Jones, H R A; Tuomi, Mikko; Salter, G S; Carter, B D; Koch, F Elliott; O'Toole, S J; Bailey, J; Wright, D

    2014-01-01

    We report the discovery of two long-period giant planets from the Anglo-Australian Planet Search. HD 154857c is in a multiple-planet system, while HD 114613b appears to be solitary. HD 114613b has an orbital period P=10.5 years, and a minimum mass m sin i of 0.48 Jupiter masses; HD 154857c has P=9.5 years and m sin i=2.6 Jupiter masses. These new data confirm the planetary nature of the previously unconstrained long-period object in the HD 154857 system. We have performed detailed dynamical stability simulations which show that the HD 154857 two-planet system is stable on timescales of at least 100 million years. These results highlight the continued importance of "legacy" surveys with long observational baselines; these ongoing campaigns are critical for determining the population of Jupiter analogs, and hence of those planetary systems with architectures most like our own Solar system.

  6. The anglo-australian planet search. XXIII. Two new Jupiter analogs

    Energy Technology Data Exchange (ETDEWEB)

    Wittenmyer, Robert A.; Horner, Jonathan; Tinney, C. G.; Salter, G. S.; Bailey, J.; Wright, D. [School of Physics, University of New South Wales, Sydney 2052 (Australia); Butler, R. P. [Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015-1305 (United States); Jones, H. R. A.; Tuomi, Mikko [University of Hertfordshire, Centre for Astrophysics Research, Science and Technology Research Institute, College Lane, AL10 9AB Hatfield (United Kingdom); Carter, B. D. [Computational Engineering and Science Research Centre, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia); Koch, F. Elliott [San Diego State University, Physics Department, 5500 Campanile Drive, San Diego, CA 92182-1233 (United States); O' Toole, S. J., E-mail: rob@phys.unsw.edu.au [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia)

    2014-03-10

    We report the discovery of two long-period giant planets from the Anglo-Australian Planet Search. HD 154857c is in a multiple-planet system, while HD 114613b appears to be solitary. HD 114613b has an orbital period P = 10.5 yr, and a minimum mass msin i of 0.48 M {sub Jup}; HD 154857c has P = 9.5 yr and msin i = 2.6 M {sub Jup}. These new data confirm the planetary nature of the previously unconstrained long-period object in the HD 154857 system. We have performed detailed dynamical stability simulations which show that the HD 154857 two-planet system is stable on timescales of at least 10{sup 8} yr. These results highlight the continued importance of 'legacy' surveys with long observational baselines; these ongoing campaigns are critical for determining the population of Jupiter analogs, and hence of those planetary systems with architectures most like our own solar system.

  7. Planets around stars in young nearby associations *** radial Velocity searches: a feasibility study, and first results

    CERN Document Server

    Lagrange, A -M; Chauvin, G; Sterzik, M; Galland, F; Curto, G Lo; Rameau, J; Sosnowska, D

    2013-01-01

    Stars in young nearby associations are the only targets allowing giant planet searches at all separations in the near future, by coupling indirect techniques such as radial velocity and deep imaging. These stars are first priorities targets for the forthcoming planets imagers on 10-m class telescopes. Young stars rotate more rapidly and are more active than their older counterparts. Both effects can limit the capability to detect planets using RV. We wish to explore the planet detection capabilities of a representative sample of stars in close and young associations with radial velocity data and explore the complementarity between this technique and direct imaging. We observed 26 such targets with spectral types from A to K and ages from 8 to 300 Myr with HARPS. We compute the detection limits. We also attempt to improve the detection limits in a few cases by correcting for the stellar activity. Our A-type stars RV show high frequency variations due to pulsations, while our F-K stars clearly show activity wit...

  8. TRAPPIST-UCDTS: A prototype search for habitable planets transiting ultra-cool stars

    Directory of Open Access Journals (Sweden)

    Magain P.

    2013-04-01

    Full Text Available The ∼1000 nearest ultra-cool stars (spectral type M6 and latter represent a unique opportunity for the search for life outside solar system. Due to their small luminosity, their habitable zone is 30–100 times closer than for the Sun, the corresponding orbital periods ranging from one to a few days. Thanks to this proximity, the transits of a habitable planet are much more probable and frequent than for an Earth-Sun analog, while their tiny size (∼1 Jupiter radius leads to transits deep enough for a ground-based detection, even for sub-Earth size planets. Furthermore, a habitable planet transiting one of these nearby ultra-cool star would be amenable for a thorough atmospheric characterization, including the detection of possible biosignatures, notably with the near-to-come JWST. Motivated by these reasons, we have set up the concept of a ground-based survey optimized for detecting planets of Earth-size and below transiting the nearest Southern ultra-cool stars. To assess thoroughly the actual potential of this future survey, we are currently conducting a prototype mini-survey using the TRAPPIST robotic 60cm telescope located at La Silla ESO Observatory (Chile. We summarize here the preliminary results of this mini-survey that fully validate our concept.

  9. TRAPPIST-UCDTS: A prototype search for habitable planets transiting ultra-cool stars

    Science.gov (United States)

    Gillon, M.; Jehin, E.; Fumel, A.; Magain, P.; Queloz, D.

    2013-04-01

    The ˜1000 nearest ultra-cool stars (spectral type M6 and latter) represent a unique opportunity for the search for life outside solar system. Due to their small luminosity, their habitable zone is 30-100 times closer than for the Sun, the corresponding orbital periods ranging from one to a few days. Thanks to this proximity, the transits of a habitable planet are much more probable and frequent than for an Earth-Sun analog, while their tiny size (˜1 Jupiter radius) leads to transits deep enough for a ground-based detection, even for sub-Earth size planets. Furthermore, a habitable planet transiting one of these nearby ultra-cool star would be amenable for a thorough atmospheric characterization, including the detection of possible biosignatures, notably with the near-to-come JWST. Motivated by these reasons, we have set up the concept of a ground-based survey optimized for detecting planets of Earth-size and below transiting the nearest Southern ultra-cool stars. To assess thoroughly the actual potential of this future survey, we are currently conducting a prototype mini-survey using the TRAPPIST robotic 60cm telescope located at La Silla ESO Observatory (Chile). We summarize here the preliminary results of this mini-survey that fully validate our concept.

  10. The SOPHIE search for northern extrasolar planets. VI. Three new hot Jupiters in multi-planet extrasolar systems

    Science.gov (United States)

    Moutou, C.; Hébrard, G.; Bouchy, F.; Arnold, L.; Santos, N. C.; Astudillo-Defru, N.; Boisse, I.; Bonfils, X.; Borgniet, S.; Delfosse, X.; Díaz, R. F.; Ehrenreich, D.; Forveille, T.; Gregorio, J.; Labrevoir, O.; Lagrange, A.-M.; Montagnier, G.; Montalto, M.; Pepe, F.; Sahlmann, J.; Santerne, A.; Ségransan, D.; Udry, S.; Vanhuysse, M.

    2014-03-01

    We present high-precision radial-velocity measurements of three solar-type stars: HD 13908, HD 159243, and HIP 91258. The observations were made with the SOPHIE spectrograph at the 1.93 m telescope of the Observatoire de Haute-Provence (France). They show that these three bright stars host exoplanetary systems composed of at least two companions. HD 13908 b is a planet with a minimum mass of 0.865 ± 0.035MJup on a circular orbit with a period of 19.382 ± 0.006 days. There is an outer massive companion in the system with a period of 931 ± 17 days, e = 0.12 ± 0.02, and a minimum mass of 5.13 ± 0.25MJup . The star HD 159243 also has two detected companions with respective masses, periods, and eccentricities of Mp= 1.13 ± 0.05 and 1.9 ± 0.13MJup , P = 12.620 ± 0.004 and 248.4 ± 4.9 days, and e = 0.02 ± 0.02 and 0.075 ± 0.05. Finally, the star HIP 91258 has a planetary companion with a minimum mass of 1.068 ± 0.038MJup , an orbital period of 5.0505 ± 0.0015 days, and a quadratic trend indicating an outer planetary or stellar companion that is as yet uncharacterized. The planet-hosting stars HD 13908, HD 159243, and HIP 91258 are main-sequence stars of spectral types F8V, G0V, and G5V, respectively, with moderate activity levels. HIP 91258 is slightly over-metallic, while the other two stars have solar-like metallicity. The three systems are discussed in the frame of formation and dynamical evolution models of systems composed of several giant planets. Tables 5-8 are available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/563/A22Tables 5-7 are also available in electronic form at http://www.aanda.orgBased on observations collected with the SOPHIE spectrograph on the 1.93 m telescope at the Observatoire de Haute-Provence (CNRS), France, by the SOPHIE RPE Consortium (program PNP.CONS).

  11. Light Curves as Predictors of Good Radial Velocity Planet Search Targets in New Stellar Domains

    Science.gov (United States)

    Bastien, Fabienne A.; Wright, Jason; Sigurdsson, Steinn; Dumusque, Xavier; Luhn, Jacob K.; Howard, Andrew

    2017-01-01

    As Kepler and K2 have collectively found thousands of exoplanet candidates, their discoveries have strained ground-based radial velocity (RV) follow-up resources, which are unable to simultaneously keep up with the pace of transit discoveries by measuring masses for all of the candidates and maintain vigorous RV searches for planets that do not transit their parent star. The burden to the RV community is expected to worsen with the upcoming TESS mission, even as new RV instruments are slated to come online in the coming years. Observations that can enable the RV community to prioritize targets on the basis of their stellar RV variability in advance and, ideally, independently of the RV instruments themselves, can therefore permit us to reserve our RV resources for the stars most likely to yield the highest payoff. We show that the light curves from space-based transit surveys may not only be used as predictors of good RV search targets for the stars predominantly targeted by the exoplanet community but also for stars usually avoided by both RV and transit surveys due to their high intrinsic levels of stellar variability. We also briefly present recommendations to the RV planet search community on how to improve prospects for finding Earth analogs from the recent workshop at the Aspen Center for Physics, “Approaching the Stellar Astrophysical Limits of Exoplanet Detection: Getting to 10cm/s.”

  12. The solar neighborhood. XXXIV. A search for planets orbiting nearby M dwarfs using astrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lurie, John C. [Department of Astronomy, University of Washington, Seattle, WA 98195 (United States); Henry, Todd J.; Ianna, Philip A. [RECONS Institute, Chambersburg, PA 17201 (United States); Jao, Wei-Chun; Quinn, Samuel N.; Winters, Jennifer G. [Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30302 (United States); Koerner, David W. [Department of Physics and Astronomy, Northern Arizona University, Flagstaff, AZ 86011 (United States); Riedel, Adric R. [Department of Astrophysics, American Museum of Natural History, New York, NY 10034 (United States); Subasavage, John P., E-mail: lurie@uw.edu [United States Naval Observatory, Flagstaff, AZ 86001 (United States)

    2014-11-01

    Astrometric measurements are presented for seven nearby stars with previously detected planets: six M dwarfs (GJ 317, GJ 667C, GJ 581, GJ 849, GJ 876, and GJ 1214) and one K dwarf (BD-10 -3166). Measurements are also presented for six additional nearby M dwarfs without known planets, but which are more favorable to astrometric detections of low mass companions, as well as three binary systems for which we provide astrometric orbit solutions. Observations have baselines of 3 to 13 years, and were made as part of the RECONS long-term astrometry and photometry program at the CTIO/SMARTS 0.9 m telescope. We provide trigonometric parallaxes and proper motions for all 16 systems, and perform an extensive analysis of the astrometric residuals to determine the minimum detectable companion mass for the 12 M dwarfs not having close stellar secondaries. For the six M dwarfs with known planets, we are not sensitive to planets, but can rule out the presence of all but the least massive brown dwarfs at periods of 2–12 years. For the six more astrometrically favorable M dwarfs, we conclude that none have brown dwarf companions, and are sensitive to companions with masses as low as 1 M{sub Jup} for periods longer than two years. In particular, we conclude that Proxima Centauri has no Jovian companions at orbital periods of 2–12 years. These results complement previously published M dwarf planet occurrence rates by providing astrometrically determined upper mass limits on potential super-Jupiter companions at orbits of two years and longer. As part of a continuing survey, these results are consistent with the paucity of super-Jupiter and brown dwarf companions we find among the over 250 red dwarfs within 25 pc observed longer than five years in our astrometric program.

  13. VizieR Online Data Catalog: Final Kepler transiting planet search (DR25) (Twicken+, 2016)

    Science.gov (United States)

    Twicken, J. D.; Jenkins, J. M.; Seader, S. E.; Tenenbaum, P.; Smith, J. C.; Brownston, L. S.; Burke, C. J.; Catanzarite, J. H.; Clarke, B. D.; Cote, M. T.; Girouard, F. R.; Klaus, T. C.; Li, J.; McCauliff, S. D.; Morris, R. L.; Wohler, B.; Campbell, J. R.; Uddin, A. K.; Zamudio, K. A.; Sabale, A.; Bryson, S. T.; Caldwell, D. A.; Christiansen, J. L.; Coughlin, J. L.; Haas, M. R.; Henze, C. E.; Sanderfer, D. T.; Thompson, S. E.

    2017-01-01

    The Kepler spacecraft is in an Earth-trailing heliocentric orbit and maintained a boresight pointing centered on α=19h22m40s, δ=+44.5° during the primary mission. The Kepler photometer acquired data on a 115-square-degree region of the sky. The data were acquired on 29.4-minute intervals, colloquially known as "long cadences". Long-cadence pixel values were obtained by accumulating 270 consecutive 6.02s exposures. Science acquisition of Q1 data began at 2009-05-13 00:01:07Z, and acquisition of Q17 data concluded at 2013-05-11 12:16:22Z. This time period contains 71427 long-cadence intervals. A total of 198709 targets observed by Kepler were searched for evidence of transiting planets in the final Q1-Q17 pipeline run (see Table1). The results of past Kepler Mission transiting planet searches have been presented in Tenenbaum et al. 2012 (Cat. J/ApJS/199/24) for Quarter 1 through Quarter 3 (i.e., Q1-Q3), Tenenbaum et al. 2013ApJS..206....5T for Q1-Q12, Tenenbaum et al. 2014ApJS..211....6T for Q1-Q16, and Seader et al. 2015 (Cat. J/ApJS/217/18) for Q1-Q17. We now present results of the final Kepler transiting planet search encompassing the complete 17-quarter primary mission. The data release for the final Q1-Q17 pipeline processing is referred to as Data Release 25 (DR25). (3 data files).

  14. The Pan-Pacific Planet Search. II. Confirmation of a two-planet system around HD 121056

    CERN Document Server

    Wittenmyer, Robert A; Liu, Fan; Horner, Jonathan; Endl, Michael; Johnson, John Asher; Tinney, C G; Carter, B D

    2014-01-01

    Precise radial velocities from the Anglo-Australian Telescope confirm the presence of a rare short-period planet around the K0 giant HD 121056. An independent two-planet solution using the AAT data shows that the inner planet has P=89.1+/-0.1 days, and m sin i=1.35+/-0.17 Mjup. These data also confirm the planetary nature of the outer companion, with m sin i=3.9+/-0.6 Mjup and a=2.96+/-0.16 AU. HD 121056 is the most-evolved star to host a confirmed multiple-planet system, and is a valuable example of a giant star hosting both a short-period and a long-period planet.

  15. THE PAN-PACIFIC PLANET SEARCH. II. CONFIRMATION OF A TWO-PLANET SYSTEM AROUND HD 121056

    Energy Technology Data Exchange (ETDEWEB)

    Wittenmyer, Robert A.; Tinney, C. G. [School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia); Wang, Liang [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, A20 Datun Road, Chaoyang District, Beijing 100012 (China); Liu, Fan [Research School of Astronomy and Astrophysics, Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia); Horner, Jonathan [Australian Centre for Astrobiology, University of New South Wales, Sydney, NSW 2052 (Australia); Endl, Michael [McDonald Observatory, University of Texas at Austin, 1 University Station C1400, Austin, TX 78712 (United States); Johnson, John Asher [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Carter, B. D., E-mail: rob@unsw.edu.au [Computational Engineering and Science Research Centre, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia)

    2015-02-10

    Precise radial velocities from the Anglo-Australian Telescope (AAT) confirm the presence of a rare short-period planet around the K0 giant HD 121056. An independent two-planet solution using the AAT data shows that the inner planet has P = 89.1 ± 0.1 days, and m sin i = 1.35 ± 0.17 M{sub Jup}. These data also confirm the planetary nature of the outer companion, with m sin i = 3.9 ± 0.6 M{sub Jup} and a = 2.96 ± 0.16 AU. HD 121056 is the most-evolved star to host a confirmed multiple-planet system, and is a valuable example of a giant star hosting both a short-period and a long-period planet.

  16. Searching for Planets in the Hyades. I The Keck Radial Velocity Survey

    CERN Document Server

    Cochran, W D; Paulson, D B; Cochran, William D.; Hatzes, Artie P.; Paulson, Diane B.

    2002-01-01

    We describe a high-precision radial velocity search for jovian-mass companions to main sequence stars in the Hyades star cluster. The Hyades provides an extremely well controlled sample of stars of the same age, the same metallicity, and a common birth and early dynamical environment. This sample allows us to explore the dependence of the process of planet formation on only a single independent variable: the stellar mass. In this paper we describe the survey and summarize results for the first five years.

  17. Mathematical programming solver based on local search

    CERN Document Server

    Gardi, Frédéric; Darlay, Julien; Estellon, Bertrand; Megel, Romain

    2014-01-01

    This book covers local search for combinatorial optimization and its extension to mixed-variable optimization. Although not yet understood from the theoretical point of view, local search is the paradigm of choice for tackling large-scale real-life optimization problems. Today's end-users demand interactivity with decision support systems. For optimization software, this means obtaining good-quality solutions quickly. Fast iterative improvement methods, like local search, are suited to satisfying such needs. Here the authors show local search in a new light, in particular presenting a new kind of mathematical programming solver, namely LocalSolver, based on neighborhood search. First, an iconoclast methodology is presented to design and engineer local search algorithms. The authors' concern about industrializing local search approaches is of particular interest for practitioners. This methodology is applied to solve two industrial problems with high economic stakes. Software based on local search induces ex...

  18. The Solar Neighborhood. XXXIV. A Search for Planets Orbiting Nearby M Dwarfs using Astrometry

    CERN Document Server

    Lurie, John C; Jao, Wei-Chun; Quinn, Samuel N; Winters, Jennifer G; Ianna, Philip A; Koerner, David W; Riedel, Adric R; Subasavage, John P

    2014-01-01

    Astrometric measurements are presented for seven nearby stars with previously detected planets: six M dwarfs (GJ 317, GJ 667C, GJ 581, GJ 849, GJ 876, and GJ 1214) and one K dwarf (BD $-$10 3166). Measurements are also presented for six additional nearby M dwarfs without known planets, but which are more favorable to astrometric detections of low mass companions, as well as three binary systems for which we provide astrometric orbit solutions. Observations have baselines of three to thirteen years, and were made as part of the RECONS long-term astrometry and photometry program at the CTIO/SMARTS 0.9m telescope. We provide trigonometric parallaxes and proper motions for all 16 systems, and perform an extensive analysis of the astrometric residuals to determine the minimum detectable companion mass for the 12 M dwarfs not having close stellar secondaries. For the six M dwarfs with known planets, we are not sensitive to planets, but can rule out the presence of all but the least massive brown dwarfs at periods o...

  19. A Search for Lost Planets in the Kepler Multi-planet Systems and the Discovery of the Long-period, Neptune-sized Exoplanet Kepler-150 f

    Science.gov (United States)

    Schmitt, Joseph R.; Jenkins, Jon M.; Fischer, Debra A.

    2017-04-01

    The vast majority of the 4700 confirmed planets (CPs) and planet candidates discovered by the Kepler mission were first found by the Kepler pipeline. In the pipeline, after a transit signal is found, all data points associated with those transits are removed, creating a “Swiss cheese”-like light curve full of holes, which is then used for subsequent transit searches. These holes could render an additional planet undetectable (or “lost”). We examine a sample of 114 stars with 3+ CPs to evaluate the effect of this “Swiss cheesing.” A simulation determines that the probability that a transiting planet is lost due to the transit masking is low, but non-negligible, reaching a plateau at ˜3.3% lost in the period range of P = 400-500 days. We then model all planet transits and subtract out the transit signals for each star, restoring the in-transit data points, and use the Kepler pipeline to search the transit-subtracted (i.e., transit-cleaned) light curves. However, the pipeline did not discover any credible new transit signals. This demonstrates the validity and robustness of the Kepler pipeline’s choice to use transit masking over transit subtraction. However, a follow-up visual search through all the transit-subtracted data, which allows for easier visual identification of new transits, revealed the existence of a new, Neptune-sized exoplanet (Kepler-150 f) and a potential single transit of a likely false positive (FP) (Kepler-208). Kepler-150 f (P = 637.2 days, {R}{{P}}={3.64}-0.39+0.52 R⊕) is confirmed with >99.998% confidence using a combination of the planet multiplicity argument, an FP probability analysis, and a transit duration analysis.

  20. A mid-infrared search for substellar companions of nearby planet-host stars

    Energy Technology Data Exchange (ETDEWEB)

    Hulsebus, A.; Marengo, M. [Department of Physics and Astronomy, 12 Physics Hall, Iowa State University, Ames, IA 50010 (United States); Carson, J. [Department of Physics and Astronomy, College of Charleston, 58 Coming Street, Charleston, SC 29424 (United States); Stapelfeldt, K. [Exoplanets and Stellar Astrophysics Laboratory, Code 667, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2014-03-20

    Determining the presence of widely separated substellar-mass companion is crucial to understand the dynamics of inner planets in extrasolar planetary systems (e.g., to explain their high mean eccentricity as inner planets are perturbed by the Kozai mechanism). We report the results of our Spitzer/Infrared Array Camera (IRAC) imaging search for widely separated (10''-25'') substellar-mass companions for 14 planet-host stars within 15 pc of the Sun. Using deep 3.6 and 4.5 μm observations in subarray mode, we found one object in the field of 47 UMa with [3.6]–[4.5] color similar to a T5 dwarf, which is, however, unlikely to share common proper motion with 47 UMa. We also found three objects with brown-dwarf-like [3.6]–[4.5] color limits in the fields of GJ 86, HD 160691, and GJ 581, as well as another in the field of HD 69830 for which we have excluded common proper motion. We provide model-based upper mass limits for unseen objects around all stars in our sample, with typical sensitivity to 10 M {sub J} objects from a projected separation of 50-300 AU from the parent star. We also discuss our data analysis methods for point-spread-function subtraction, image co-alignment, and artifact subtraction of IRAC subarray images.

  1. A Mid-Infrared Search for Substellar Companions of Nearby Planet-Host Stars

    CERN Document Server

    Hulsebus, Alan; Carson, Joe; Stapelfeldt, Karl

    2014-01-01

    Determining the presence of widely separated substellar-mass companion is crucial to understand the dynamics of inner planets in extrasolar planetary systems (e.g. to explain their high mean eccentricity as inner planets are perturbed by the Kozai mechanism). We report the results of our $\\textit{Spitzer}$/Infrared Array Camera (IRAC) imaging search for widely separated (10 to 25$^{\\prime\\prime}$) substellar-mass companions for 14 planet-host stars within 15 pc of the Sun. Using deep 3.6 and 4.5 $\\mu$m observations in subarray mode, we found one object in the field of 47 UMa with [3.6]$-$[4.5] color similar to a T5 dwarf, which is, however, unlikely to share common proper motion with 47 UMa. We also found three objects with brown-dwarf-like [3.6]$-$[4.5] color limits in the fields of GJ 86, HD 160691, and GJ 581, as well as another in the field of HD 69830 for which we have excluded common proper motion. We provide model-based upper mass limits for unseen objects around all stars in our sample, with typical s...

  2. NACO-SDI imaging of known companion host stars from the AAPS and Keck planet search surveys

    CERN Document Server

    Jenkins, J S; Biller, B; O'Toole, S J; Pinfield, D J; Close, L; Tinney, C G; Butler, R P; Wittenmyer, R; Carter, B; Day-Jones, A C

    2010-01-01

    Direct imaging of brown dwarfs as companions to solar-type stars can provide a wealth of well-constrained data to "benchmark" the physics of such objects, since quantities like metallicity and age can be determined from their well-studied primaries. We present results from an adaptive optics imaging program on stars drawn from the Anglo-Australian and Keck Planet Search projects, with the aim of directly imaging known cool companions. Simulations have modeled the expected contrast ratios and separations of known companions using estimates of orbital parameters available from current radial-velocity data and then a selection of the best case objects were followed-up with high contrast imaging to attempt to directly image these companions. These simulations suggest that only a very small number of radial-velocity detected exoplanets with consistent velocity fits and age estimates could potentially be directly imaged using the VLT's Simultaneous Differential Imaging system and only under favorable conditions. We...

  3. VizieR Online Data Catalog: Pan-Pacific Planet Search (PPPS). V. 164 stars (Wittenmyer+, 2016)

    Science.gov (United States)

    Wittenmyer, R. A.; Liu, F.; Wang, L.; Casagrande, L.; Johnson, J. A.; Tinney, C. G.

    2016-09-01

    The Pan-Pacific Planet Search (PPPS) operated at the 3.9m Anglo-Australian Telescope (AAT) from 2009 to 2014, targeting 164 southern hemisphere evolved stars (see Paper I, Wittenmyer et al. 2011, Cat. J/ApJ/743/184). All observations were carried out at the AAT using its UCLES echelle spectrograph. The PPPS program uses the Doppler technique for measuring precise radial velocities, with an iodine absorption cell to calibrate the spectrograph point-spread function. An iodine-free "template" observation is acquired for each target at a resolution R~60000 and a signal-to-noise of 100-300pixel-1. In this work, we use the iodine-free templates to determine spectroscopic stellar atmospheric parameters. (5 data files).

  4. Program Service Reports Search Tool

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Program Service Reports provide information on reported demographics, services, and federal monitoring of Head Start and Early Head Start programs, beginning...

  5. MINING PLANET SEARCH DATA FOR BINARY STARS: THE ψ{sup 1} DRACONIS SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Gullikson, Kevin; Endl, Michael; Cochran, William D.; MacQueen, Phillip J., E-mail: kgulliks@astro.as.utexas.edu [University of Texas, Astronomy Department, 2515 Speedway, Stop C1400, Austin, TX 78712 (United States)

    2015-12-10

    Several planet-search groups have acquired a great deal of data in the form of time-series spectra of several hundred nearby stars with time baselines of over a decade. While binary star detections are generally not the goal of these long-term monitoring efforts, the binary stars hiding in existing planet search data are precisely the type that are too close to the primary star to detect with imaging or interferometry techniques. We use a cross-correlation analysis to detect the spectral lines of a new low-mass companion to ψ{sup 1} Draconis A, which has a known roughly equal-mass companion at ∼680 AU. We measure the mass of ψ{sup 1} Draconis C as M{sub 2} = 0.70 ± 0.07M{sub ⊙}, with an orbital period of ∼20 years. This technique could be used to characterize binary companions to many stars that show large-amplitude modulation or linear trends in radial velocity data.

  6. Mining Planet Search Data for Binary Stars: The $\\psi^1$ Draconis system

    CERN Document Server

    Gullikson, Kevin; Cochran, William D; MacQueen, Phillip J

    2015-01-01

    Several planet-search groups have acquired a great deal of data in the form of time-series spectra of several hundred nearby stars with time baselines of over a decade. While binary star detections are generally not the goal of these long-term monitoring efforts, the binary stars hiding in existing planet search data are precisely the type that are too close to the primary star to detect with imaging or interferometry techniques. We use a cross-correlation analysis to detect the spectral lines of a new low-mass companion to $\\psi^1$ Draconis A, which has a known roughly equal-mass companion at ${\\sim}680$ AU. We measure the mass of $\\psi^1$ Draconis C as $M_2 = 0.70 \\pm 0.07 M_{\\odot}$, with an orbital period of ${\\sim}20$ years. This technique could be used to characterize binary companions to many stars that show large-amplitude modulation or linear trends in radial velocity data.

  7. Mining Planet Search Data for Binary Stars: The ψ1 Draconis system

    Science.gov (United States)

    Gullikson, Kevin; Endl, Michael; Cochran, William D.; MacQueen, Phillip J.

    2015-12-01

    Several planet-search groups have acquired a great deal of data in the form of time-series spectra of several hundred nearby stars with time baselines of over a decade. While binary star detections are generally not the goal of these long-term monitoring efforts, the binary stars hiding in existing planet search data are precisely the type that are too close to the primary star to detect with imaging or interferometry techniques. We use a cross-correlation analysis to detect the spectral lines of a new low-mass companion to ψ1 Draconis A, which has a known roughly equal-mass companion at ∼680 AU. We measure the mass of ψ1 Draconis C as M2 = 0.70 ± 0.07M⊙, with an orbital period of ∼20 years. This technique could be used to characterize binary companions to many stars that show large-amplitude modulation or linear trends in radial velocity data.

  8. Advances in the Kepler Transit Search Engine and Automated Approaches to Identifying Likely Planet Candidates in Transit Surveys

    Science.gov (United States)

    Jenkins, Jon Michael

    2015-08-01

    Twenty years ago, no planets were known outside our own solar system. Since then, the discoveries of ~1500 exoplanets have radically altered our views of planets and planetary systems. This revolution is due in no small part to the Kepler Mission, which has discovered >1000 of these planets and >4000 planet candidates. While Kepler has shown that small rocky planets and planetary systems are quite common, the quest to find Earth’s closest cousins and characterize their atmospheres presses forward with missions such as NASA Explorer Program’s Transiting Exoplanet Survey Satellite (TESS) slated for launch in 2017 and ESA’s PLATO mission scheduled for launch in 2024.These future missions pose daunting data processing challenges in terms of the number of stars, the amount of data, and the difficulties in detecting weak signatures of transiting small planets against a roaring background. These complications include instrument noise and systematic effects as well as the intrinsic stellar variability of the subjects under scrutiny. In this paper we review recent developments in the Kepler transit search pipeline improving both the yield and reliability of detected transit signatures.Many of the phenomena in light curves that represent noise can also trigger transit detection algorithms. The Kepler Mission has expended great effort in suppressing false positives from its planetary candidate catalogs. While over 18,000 transit-like signatures can be identified for a search across 4 years of data, most of these signatures are artifacts, not planets. Vetting all such signatures historically takes several months’ effort by many individuals. We describe the application of machine learning approaches for the automated vetting and production of planet candidate catalogs. These algorithms can improve the efficiency of the human vetting effort as well as quantifying the likelihood that each candidate is truly a planet. This information is crucial for obtaining valid planet

  9. The HARPS search for southern extra-solar planets XXXV. Super-Earths around the M-dwarf neighbors Gl433 and Gl667C

    CERN Document Server

    Delfosse, X; Forveille, T; Udry, S; Mayor, M; Bouchy, F; Gillon, M; Lovis, C; Neves, V; Pepe, F; Perrier, C; Queloz, D; Santos, N C; Ségransan, D

    2012-01-01

    M dwarfs have been found to often have super-Earth planets with short orbital periods. Such stars are thus preferential targets in searches for rocky or ocean planets in the solar neighbourhood. In a recent paper (Bonfils et al. 2011), we announced the discovery of respectively 1 and 2 low mass planets around the M1.5V stars Gl433 and Gl667C. We found those planets with the HARPS spectrograph on the ESO~3.6-m telescope at La Silla Observatory, from observations obtained during the Guaranteed Time Observing program of that instrument. We have obtained additional HARPS observations of those two stars, for a total of respectively 67 and 179 Radial Velocity measurements for Gl433 and Gl667C, and present here an orbital analysis of those extended data sets and our main conclusion about both planetary systems. One of the three planets, Gl667Cc, has a mass of only M2.sin(i)~4.25 M_earth and orbits in the central habitable zone of its host star. It receives just 10% less stellar energy from Gl667C than the Earth rece...

  10. New Planetary Systems from the Calan-Hertfordshire Extrasolar Planet Search and the Core Accretion Mass Limit

    CERN Document Server

    Jenkins, J S; Tuomi, M; Díaz, M; Cordero, J P; Aguayo, A; Pantoja, B; Arriagada, P; Mahu, R; Brahm, R; Rojo, P; Soto, M G; Ivanyuk, O; Yoma, N Becerra; Day-Jones, A C; Ruiz, M T; Pavlenko, Y V; Barnes, J R; Murgas, F; Pinfield, D J; Jones, M I; López-Morales, M; Shectman, S; Butler, R P; Minniti, D

    2016-01-01

    We report the discovery of eight new giant planets, and updated orbits for four known planets, orbiting dwarf and subgiant stars, using the CORALIE, HARPS, and MIKE instruments as part of the Calan-Hertfordshire Extrasolar Planet Search. We include radial velocity data prior- and post-2014 CORALIE upgrade and our Bayesian updating method returned a systematic offset of 19.2$\\pm$4.8 m/s between the two velocity sets for our stars. The planets have masses in the range 1.1-5.4M$_{\\rm{J}}$s, orbital periods from 40-2900 days, and eccentricities from 0.0-0.6. They include a double-planet system orbiting the most massive star in our sample (HD147873), two eccentric giant planets (HD128356$b$ and HD154672$b$), and a rare 14~Herculis analogue (HD224538$b$). We find that there is an over-abundance of Jupiter-mass objects compared to a simple power law fit to the mass function, with a steep increase in the planet frequency around 3M$_{\\rm{J}}$, reflecting the increased efficiency of planet formation towards lower masse...

  11. The SOPHIE search for northern extrasolar planets. III. A Jupiter-mass companion around HD 109246

    Science.gov (United States)

    Boisse, I.; Eggenberger, A.; Santos, N. C.; Lovis, C.; Bouchy, F.; Hébrard, G.; Arnold, L.; Bonfils, X.; Delfosse, X.; Desort, M.; Díaz, R. F.; Ehrenreich, D.; Forveille, T.; Gallenne, A.; Lagrange, A. M.; Moutou, C.; Udry, S.; Pepe, F.; Perrier, C.; Perruchot, S.; Pont, F.; Queloz, D.; Santerne, A.; Ségransan, D.; Vidal-Madjar, A.

    2010-11-01

    We report the detection of a Jupiter-mass planet discovered with the SOPHIE spectrograph mounted on the 1.93-m telescope at the Haute-Provence Observatory. The new planet orbits HD 109246, a G0V star slightly more metallic than the Sun. HD 109246b has a minimum mass of 0.77 MJup, an orbital period of 68 days, and an eccentricity of 0.12. It is placed in a sparsely populated region of the period distribution of extrasolar planets. We also present a correction method for the so-called seeing effect that affects the SOPHIE radial velocities. We complement this discovery announcement with a description of some calibrations that are implemented in the SOPHIE automatic reduction pipeline. These calibrations allow the derivation of the photon-noise radial velocity uncertainty and some useful stellar properties (v sin i, [Fe/H], log R’HK) directly from the SOPHIE data. Based on observations made with the SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS/OAMP), France (program 07A.PNP.CONS).RV tables (Tables C.1 and C.2) are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/523/A88

  12. 20 CFR 617.49 - Job Search Program.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Job Search Program. 617.49 Section 617.49... FOR WORKERS UNDER THE TRADE ACT OF 1974 Job Search Program § 617.49 Job Search Program. (a) Program... approved job search program (JSP), or have completed a JSP, as a condition for receiving TRA, except where...

  13. OPUS - Outer Planets Unified Search with Enhanced Surface Geometry Parameters - Not Just for Rings

    Science.gov (United States)

    Gordon, Mitchell; Showalter, Mark Robert; Ballard, Lisa; Tiscareno, Matthew S.; Heather, Neil

    2016-10-01

    In recent years, with the massive influx of data into the PDS from a wide array of missions and instruments, finding the precise data you need has been an ongoing challenge. For remote sensing data obtained from Jupiter to Pluto, that challenge is being addressed by the Outer Planets Unified Search, more commonly known as OPUS.OPUS is a powerful search tool available at the PDS Ring-Moon Systems Node (RMS) - formerly the PDS Rings Node. While OPUS was originally designed with ring data in mind, its capabilities have been extended to include all of the targets within an instrument's field of view. OPUS provides preview images of search results, and produces a zip file for easy download of selected products, including a table of user specified metadata. For Cassini ISS and Voyager ISS we have generated and include calibrated versions of every image.Currently OPUS supports data returned by Cassini ISS, UVIS, VIMS, and CIRS (Saturn data through June 2010), New Horizons Jupiter LORRI, Galileo SSI, Voyager ISS and IRIS, and Hubble (ACS, WFC3 and WFPC2).At the RMS Node, we have developed and incorporated into OPUS detailed geometric metadata, based on the most recent SPICE kernels, for all of the bodies in the Cassini Saturn observations. This extensive set of geometric metadata is unique to the RMS Node and enables search constraints such as latitudes and longitudes (Saturn, Titan, and icy satellites), viewing and illumination geometry (phase, incidence and emission angles), and distances and resolution.Our near term plans include adding the full set of Cassini CIRS Saturn data (with enhanced geometry), New Horizons MVIC Jupiter encounter images, New Horizons LORRI and MVIC Pluto data, HST STIS observations, and Cassini and Voyager ring occultations. We also plan to develop enhanced geometric metadata for the New Horizons LORRI and MVIC instruments for both the Jupiter and the Pluto encounters.OPUS: http://pds-rings.seti.org/search/

  14. A Deep Search for Additional Satellites around the Dwarf Planet Haumea

    CERN Document Server

    Burkhart, Luke D; Brown, Michael E

    2016-01-01

    Haumea is a dwarf planet with two known satellites, an unusually high spin rate, and a large collisional family, making it one of the most interesting objects in the outer solar system. A fully self-consistent formation scenario responsible for the satellite and family formation is still elusive, but some processes predict the initial formation of many small moons, similar to the small moons recently discovered around Pluto. Deep searches for regular satellites around KBOs are difficult due to observational limitations, but Haumea is one of the few for which sufficient data exist. We analyze Hubble Space Telescope (HST) observations, focusing on a ten-consecutive-orbit sequence obtained in July 2010, to search for new very small satellites. To maximize the search depth, we implement and validate a non-linear shift-and-stack method. No additional satellites of Haumea are found, but by implanting and recovering artificial sources, we characterize our sensitivity. At distances between $\\sim$10,000 km and $\\sim$3...

  15. ASTEP South: An Antarctic Search for Transiting Planets around the celestial South pole

    CERN Document Server

    Crouzet, Nicolas; Blazit, Alain; Bonhomme, Serge; Fanteï-Caujolle, Yan; Fressin, François; Guillot, Tristan; Schmider, François-Xavier; Valbousquet, Franck; Bondoux, Erick; Challita, Zalpha; Abe, Lyu; Daban, Jean-Baptiste; Gouvret, Carole

    2008-01-01

    ASTEP South is the first phase of the ASTEP project that aims to determine the quality of Dome C as a site for future photometric searches for transiting exoplanets and discover extrasolar planets from the Concordia base in Antarctica. ASTEP South consists of a front-illuminated 4k x 4k CCD camera, a 10 cm refractor, and a simple mount in a thermalized enclosure. A double-glass window is used to reduce temperature variations and its accompanying turbulence on the optical path. The telescope is fixed and observes a 4 x 4 square degrees field of view centered on the celestial South pole. With this design, A STEP South is very stable and observes with low and constant airmass, both being important issues for photometric precision. We present the project, we show that enough stars are present in our field of view to allow the detection of one to a few transiting giant planets, and that the photometric precision of the instrument should be a few mmag for stars brighter than magnitude 12 and better than 10 mmag for...

  16. The SOPHIE search for northern extrasolar planets IX. Populating the brown dwarf desert

    CERN Document Server

    Wilson, P A; Santos, N C; Sahlmann, J; Montagnier, G; Astudillo-Defru, N; Boisse, I; Bouchy, F; Rey, J; Arnold, L; Bonfils, X; Bourrier, V; Courcol, B; Deleuil, M; Delfosse, X; Díaz, R F; Ehrenreich, D; Forveille, T; Moutou, C; Pepe, F; Santerne, A; Ségransan, D; Udry, S

    2016-01-01

    Radial velocity planet search surveys of nearby Solar-type stars have shown a strong deficit of brown dwarf companions within $\\sim5\\,\\mathrm{AU}$. There is presently no comprehensive explanation of this lack of brown dwarf companions, therefore, increasing the sample of such objects is crucial to understand their formation and evolution. Based on precise radial velocities obtained using the SOPHIE spectrograph at Observatoire de Haute-Provence we characterise the orbital parameters of $15$ companions to solar-type stars and constrain their true mass using astrometric data from the Hipparcos space mission. The nine companions not shown to be stellar in nature have minimum masses ranging from ~$13$ to $70\\,\\mathrm{M}_{\\mathrm{Jup}}$, and are well distributed across the planet/brown dwarf mass regime, making them an important contribution to the known population of massive companions around solar-type stars. We characterise six companions as stellar in nature with masses ranging from a minimum mass of $76 \\pm 4...

  17. The Solar Twin Planet Search. I. Fundamental parameters of the stellar sample

    CERN Document Server

    Ramirez, I; Bean, J; Asplund, M; Bedell, M; Monroe, T; Casagrande, L; Schirbel, L; Dreizler, S; Teske, J; Maia, M Tucci; Alves-Brito, A; Baumann, P

    2014-01-01

    We are carrying out a search for planets around a sample of solar twin stars using the HARPS spectrograph. The goal of this project is to exploit the advantage offered by solar twins to obtain chemical abundances of unmatched precision. This survey will enable new studies of the stellar composition -- planet connection. Here we used the MIKE spectrograph on the Magellan Clay Telescope to acquire high resolution, high signal-to-noise ratio spectra of our sample stars. We measured the equivalent widths of iron lines and used strict differential excitation/ionization balance analysis to determine atmospheric parameters of unprecedented internal precision (DTeff=7K, Dlogg=0.019, D[Fe/H]=0.006dex, Dvt=0.016km/s). Reliable relative ages and highly precise masses were then estimated using theoretical isochrones. The spectroscopic parameters we derived are in good agreement with those measured using other independent techniques. The root-mean-square scatter of the differences seen is fully compatible with the observa...

  18. The Pan-Pacific Planet Search V. Fundamental Parameters for 164 Evolved Stars

    CERN Document Server

    Wittenmyer, Robert A; Wang, Liang; Casagrande, Luca; Johnson, John Asher; Tinney, C G

    2016-01-01

    We present spectroscopic stellar parameters for the complete target list of 164 evolved stars from the Pan-Pacific Planet Search, a five-year radial velocity campaign using the 3.9m Anglo-Australian Telescope. For 87 of these bright giants, our work represents the first determination of their fundamental parameters. Our results carry typical uncertainties of 100 K, 0.15 dex, and 0.1 dex in $T_{\\rm eff}$, $\\log g$, and [Fe/H] and are consistent with literature values where available. The derived stellar masses have a mean of $1.31^{+0.28}_{-0.25}$ Msun, with a tail extending to $\\sim$2 Msun, consistent with the interpretation of these targets as "retired" A-F type stars.

  19. The SOPHIE search for northern extrasolar planets. X. Detection and characterization of giant planets by the dozen

    CERN Document Server

    Hebrard, G; Forveille, T; Correia, A C M; Laskar, J; Bonfils, X; Boisse, I; Diaz, R F; Hagelberg, J; Sahlmann, J; Santos, N C; Astudillo-Defru, N; Borgniet, S; Bouchy, F; Bourrier, V; Courcol, B; Delfosse, X; Deleuil, M; Demangeon, O; Ehrenreich, D; Gregorio, J; Jovanovic, N; Labrevoir, O; Lagrange, A -M; Lovis, C; Lozi, J; Moutou, C; Montagnier, G; Pepe, F; Rey, J; Santerne, A; Segransan, D; Udry, S; Vanhuysse, M; Vigan, A; Wilson, P A

    2016-01-01

    We present new radial velocity measurements of eight stars secured with the spectrograph SOPHIE at the 193-cm telescope of the Haute-Provence Observatory allowing the detection and characterization of new giant extrasolar planets. The host stars are dwarfs of spectral types between F5 and K0 and magnitudes between 6.7 and 9.6; the planets have minimum masses M_p sin i between 0.4 to 3.8 M_Jup and orbital periods of several days to several months. The data allow only single planets to be discovered around the first six stars (HD143105, HIP109600, HD35759, HIP109384, HD220842, and HD12484), but one of them shows the signature of an additional substellar companion in the system. The seventh star, HIP65407, allows the discovery of two giant planets, just outside the 12:5 resonance in weak mutual interaction. The last star, HD141399, was already known to host a four-planetary system; our additional data and analyses allow new constraints to be put on it. We present Keplerian orbits of all systems, together with dy...

  20. Mission to Planet Earth: A program to understand global environmental change

    Science.gov (United States)

    1994-01-01

    A description of Mission to Planet Earth, a program to understand global environmental change, is presented. Topics discussed include: changes in the environment; global warming; ozone depletion; deforestation; and NASA's role in global change research.

  1. The Penn State - Toruń Centre for Astronomy Planet Search stars

    Science.gov (United States)

    Niedzielski, A.; Deka-Szymankiewicz, B.; Adamczyk, M.; Adamów, M.; Nowak, G.; Wolszczan, A.

    2016-01-01

    Aims: We present the complete spectroscopic analysis of 455 stars observed within the Penn State - Toruń Centre for Astronomy Planet Search (PTPS) with the High Resolution Spectrograph of the 9.2 m Hobby-Eberly Telescope. We also present the total sample of 744 evolved stars of the PTPS and discuss masses of stellar hosts in our and other surveys devoted to evolved planetary systems. Methods: Stellar atmospheric parameters were determined through a strictly spectroscopic LTE analysis of equivalent widths of Fe I and Fe II lines. Rotational velocities were obtained from fitting synthetic spectra. Radial velocities were obtained from fitting a Gaussian function to the cross-correlation function. We determined stellar masses, ages, and luminosities with a Bayesian analysis of theoretical isochrones. The radii were calculated either from derived masses and log g or from Teff and luminosities. Results: We present basic atmospheric parameters (Teff, log g, vt and [Fe/H]), rotation velocities, and absolute radial velocities as well as luminosities, masses, ages and radii for 402 stars (including 11 single-line spectroscopic binaries) that are mostly subgiants and giants. For 272 of them we present parameters for the first time. For another 53 stars we present estimates of Teff and log g based on photometric calibrations. More than half of the objects were found to be subgiants, but there is also a large group of giants, and a few stars appear to be dwarfs. The results show that the sample is composed of stars with masses ranging from 0.52 to 3.21 M⊙, 17 of which have masses ≥2.0 M⊙. The stellar radii range from 0.66 to 36.04 R⊙, with the vast majority having radii between 2.0 and 4.0 R⊙. They are generally less metal abundant than the Sun with a median [ Fe/H ] = -0.07. For 62 stars that we have in common with other planet searches, the stellar atmospheric parameters we found agree very well. We also present basic properties of the complete list of 744 stars

  2. The Solar Twin Planet Search. V. Close-in, low-mass planet candidates and evidence of planet accretion in the solar twin HIP 68468

    CERN Document Server

    Melendez, Jorge; Bean, Jacob L; Ramirez, Ivan; Asplund, Martin; Dreizler, Stefan; Yan, Hong-Liang; Shi, Jian-Rong; Lind, Karin; Ferraz-Mello, Sylvio; Galarza, Jhon Yana; Santos, Leonardo dos; Spina, Lorenzo; Maia, Marcelo Tucci; Alves-Brito, Alan; Monroe, TalaWanda; Casagrande, Luca

    2016-01-01

    [Methods]. We obtained high-precision radial velocities with HARPS on the ESO 3.6 m telescope and determined precise stellar elemental abundances (~0.01 dex) using MIKE spectra on the Magellan 6.5m telescope. [Results]. Our data indicate the presence of a planet with a minimum mass of 26 Earth masses around the solar twin HIP 68468. The planet is a super-Neptune, but unlike the distant Neptune in our solar system (30 AU), HIP 68468c is close-in, with a semi-major axis of 0.66 AU, similar to that of Venus. The data also suggest the presence of a super-Earth with a minimum mass of 2.9 Earth masses at 0.03 AU; if the planet is confirmed, it will be the fifth least massive radial velocity planet discovery to date and the first super-Earth around a solar twin. Both isochrones (5.9 Gyr) and the abundance ratio [Y/Mg] (6.4 Gyr) indicate an age of about 6 billion years. The star is enhanced in refractory elements when compared to the Sun, and the refractory enrichment is even stronger after corrections for Galactic c...

  3. The Solar Twin Planet Search. V. Close-in, low-mass planet candidates and evidence of planet accretion in the solar twin HIP 68468

    Science.gov (United States)

    Meléndez, Jorge; Bedell, Megan; Bean, Jacob L.; Ramírez, Iván; Asplund, Martin; Dreizler, Stefan; Yan, Hong-Liang; Shi, Jian-Rong; Lind, Karin; Ferraz-Mello, Sylvio; Galarza, Jhon Yana; dos Santos, Leonardo; Spina, Lorenzo; Maia, Marcelo Tucci; Alves-Brito, Alan; Monroe, TalaWanda; Casagrande, Luca

    2017-01-01

    Context. More than two thousand exoplanets have been discovered to date. Of these, only a small fraction have been detected around solar twins, which are key stars because we can obtain accurate elemental abundances especially for them, which is crucial for studying the planet-star chemical connection with the highest precision. Aims: We aim to use solar twins to characterise the relationship between planet architecture and stellar chemical composition. Methods: We obtained high-precision (1 m s-1) radial velocities with the HARPS spectrograph on the ESO 3.6 m telescope at La Silla Observatory and determined precise stellar elemental abundances ( 0.01 dex) using spectra obtained with the MIKE spectrograph on the Magellan 6.5 m telescope. Results: Our data indicate the presence of a planet with a minimum mass of 26 ± 4 Earth masses around the solar twin HIP 68468. The planet is more massive than Neptune (17 Earth masses), but unlike the distant Neptune in our solar system (30 AU), HIP 68468c is close-in, with a semi-major axis of 0.66 AU, similar to that of Venus. The data also suggest the presence of a super-Earth with a minimum mass of 2.9 ± 0.8 Earth masses at 0.03 AU; if the planet is confirmed, it will be the fifth least massive radial velocity planet candidate discovery to date and the first super-Earth around a solar twin. Both isochrones (5.9 ± 0.4 Gyr) and the abundance ratio [Y/Mg] (6.4 ± 0.8 Gyr) indicate an age of about 6 billion years. The star is enhanced in refractory elements when compared to the Sun, and the refractory enrichment is even stronger after corrections for Galactic chemical evolution. We determined a nonlocal thermodynamic equilibrium Li abundance of 1.52 ± 0.03 dex, which is four times higher than what would be expected for the age of HIP 68468. The older age is also supported by the low log () (-5.05) and low jitter (existence of the planets that are indicated by our data and to better constrain the nature of the planetary system

  4. The HARPS search for southern extra-solar planets. XLII. A system of Earth-mass planets around the nearby M dwarf YZ Ceti

    Science.gov (United States)

    Astudillo-Defru, N.; Díaz, R. F.; Bonfils, X.; Almenara, J. M.; Delisle, J.-B.; Bouchy, F.; Delfosse, X.; Forveille, T.; Lovis, C.; Mayor, M.; Murgas, F.; Pepe, F.; Santos, N. C.; Ségransan, D.; Udry, S.; Wünsche, A.

    2017-09-01

    Exoplanet surveys have shown that systems with multiple low-mass planets on compact orbits are common. Except for a few cases, however, the masses of these planets are generally unknown. At the very end of the main sequence, host stars have the lowest mass and hence offer the largest reflect motion for a given planet. In this context, we monitored the low-mass (0.13 M⊙) M dwarf YZ Cet (GJ 54.1, HIP 5643) intensively and obtained radial velocities and stellar-activity indicators derived from spectroscopy and photometry, respectively. We find strong evidence that it is orbited by at least three planets in compact orbits (POrb = 1.97, 3.06, 4.66 days), with the inner two near a 2:3 mean-motion resonance. The minimum masses are comparable to the mass of Earth (M sin i = 0.75 ± 0.13, 0.98 ± 0.14, and 1.14 ± 0.17 M⊕), and they are also the lowest masses measured by radial velocity so far. We note the possibility for a fourth planet with an even lower mass of M sin i = 0.472 ± 0.096 M⊕ at POrb = 1.04 days. An n-body dynamical model is used to place further constraints on the system parameters. At 3.6 parsecs, YZ Cet is the nearest multi-planet system detected to date. Based on observations made with the HARPS instrument on the ESO 3.6 m telescope under the program IDs 180.C-0886(A), 183.C-0437(A), and 191.C-0873(A) at Cerro La Silla (Chile).Radial velocity data (Table B.4) are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/605/L11

  5. Present and Near-Future Reflected Light Searches for Close-In Planets

    CERN Document Server

    Charbonneau, D; Charbonneau, David; Noyes, Robert W.

    2000-01-01

    Close-in extrasolar giant planets may be directly detectable by theirreflected light, due to the proximity of the planet to the illuminating star.The spectrum of the system will contain a reflected light component that variesin amplitude and Doppler shift as the planet orbits the star. Intensivesearches for this effect have been carried out for only one extrasolar planetsystem, tau Boo. There exist several other attractive targets, including thetransiting planet system HD 209458.

  6. Planets or Pretense?: The Search for Substellar Objects around Post Common Envelope Binaries

    Science.gov (United States)

    Hardy, Adam; Schreiber, Matthias R.; Parsons, Steven; Caceres, Claudio; Canovas, Hector

    2015-12-01

    Many believe post-common envelope binary systems (PCEBs), consisting of a white dwarf and a close main-sequence companion, host a unique class of planetary system. Given the well known age and history of the host binary stars, these systems have the potential to provide new insights into the evolution of planetary systems. However, the existence of the planets should be treated with some skepticism as their presence has so far been inferred only by the indirect method of eclipse timing variations. This method has proved somewhat flawed, as many of the claimed planetary systems have been found dynamically unstable, and others have dramatically failed when confronted with more recent high-precision times. It is therefore of the utmost importance that complementary observations be performed to test the planetary hypothesis, and we have recently performed two such pioneering observations:1. We use SPHERE on the VLT to image the PCEB V471 Tau. A circumbinary companion to this PCEB has been predicted for more than 30 years with eclipse timings, but only recently has a direct detection become technically possible.2. We use ALMA to search for dusty material around the young PCEB NN Ser. The planetary model for NN Ser is one of the most convincing, and these planets would likely be present alongside considerable dusty material, now detectable thanks to the sensitivity of ALMA.I will present the results of these two important observations and discuss their far-reaching implications for the existence and charactistics of planetary systems around PCEBs.

  7. The Earth as a Distant Planet A Rosetta Stone for the Search of Earth-Like Worlds

    CERN Document Server

    Vázquez, M; Montañés Rodríguez, P

    2010-01-01

    Is the Earth, in some way, special? Or is our planet but one of the millions of other inhabited planets within our galaxy? This is an exciting time to be asking this old question, because for the first time in history, the answer is within reach. In The Earth as a Distant Planet, the authors set themselves as external observers of our Solar System from an astronomical distance. From that perspective, the authors describe how the Earth, the third planet in distance to the central star, can be catalogued as having its own unique features and as capable of sustaining life. The knowledge gained from this original perspective is then applied to the ongoing search for planets outside the solar system, or exoplanets. Since the discovery in 1992 of the first exoplanet, the number of known planets has increased exponentially. Ambitious space missions are already being designed for the characterization of their atmospheres and to explore the possibility that they host life. The exploration of Earth and the rest of the ...

  8. The HARPS search for southern extra-solar planets. XVII. Super-Earth and Neptune-mass planets in multiple planet systems HD47186 and HD181433

    CERN Document Server

    Bouchy, F; Lovis, C; Udry, S; Benz, W; Bertaux, J-L; Delfosse, X; Mordasini, C; Pepe, F; Queloz, D; Ségransan, D

    2008-01-01

    This paper reports on the detection of two new multiple planet systems around solar-like stars HD47186 and HD181433. The first system includes a hot Neptune of 22.78 M_Earth at 4.08-days period and a Saturn of 0.35 M_Jup at 3.7-years period. The second system includes a Super-Earth of 7.5 M_Earth at 9.4-days period, a 0.64 M$_Jup at 2.6-years period as well as a third companion of 0.54 M_Jup with a period of about 6 years. These detections increase to 20 the number of close-in low-mass exoplanets (below 0.1 M_Jup) and strengthen the fact that 80% of these planets are in a multiple planetary systems.

  9. Hybrid Differential Dynamic Programming with Stochastic Search

    Science.gov (United States)

    Aziz, Jonathan; Parker, Jeffrey; Englander, Jacob

    2016-01-01

    Differential dynamic programming (DDP) has been demonstrated as a viable approach to low-thrust trajectory optimization, namely with the recent success of NASAs Dawn mission. The Dawn trajectory was designed with the DDP-based Static Dynamic Optimal Control algorithm used in the Mystic software. Another recently developed method, Hybrid Differential Dynamic Programming (HDDP) is a variant of the standard DDP formulation that leverages both first-order and second-order state transition matrices in addition to nonlinear programming (NLP) techniques. Areas of improvement over standard DDP include constraint handling, convergence properties, continuous dynamics, and multi-phase capability. DDP is a gradient based method and will converge to a solution nearby an initial guess. In this study, monotonic basin hopping (MBH) is employed as a stochastic search method to overcome this limitation, by augmenting the HDDP algorithm for a wider search of the solution space.

  10. ASTEP South: An Antarctic Search for Transiting ExoPlanets around the celestial South pole

    CERN Document Server

    Crouzet, Nicolas; Agabi, Karim; Rivet, Jean-Pierre; Bondoux, Erick; Challita, Zalpha; Fanteï-Caujolle, Yan; Fressin, François; Mékarnia, Djamel; Schmider, François-Xavier; Valbousquet, Franck; Blazit, Alain; Bonhomme, Serge; Abe, Lyu; Daban, Jean-Baptiste; Gouvret, Carole; Fruth, Thomas; Rauer, Heike; Erikson, Anders; Barbieri, Mauro; Aigrain, Suzanne; Pont, Frédéric

    2009-01-01

    ASTEP South is the first phase of the ASTEP project (Antarctic Search for Transiting ExoPlanets). The instrument is a fixed 10 cm refractor with a 4kx4k CCD camera in a thermalized box, pointing continuously a 3.88 degree x 3.88 degree field of view centered on the celestial South pole. ASTEP South became fully functional in June 2008 and obtained 1592 hours of data during the 2008 Antarctic winter. The data are of good quality but the analysis has to account for changes in the point spread function due to rapid ground seeing variations and instrumental effects. The pointing direction is stable within 10 arcseconds on a daily timescale and drifts by only 34 arcseconds in 50 days. A truly continuous photometry of bright stars is possible in June (the noon sky background peaks at a magnitude R=15 arcsec-2 on June 22), but becomes challenging in July (the noon sky background magnitude is R=12.5 arcsec?2 on July 20). The weather conditions are estimated from the number of stars detected in the field. For the 2008...

  11. The CORALIE survey for Southern extra-solar planets. IV. Intrinsic stellar limitations to planet searches with radial-velocity techniques

    Science.gov (United States)

    Santos, N. C.; Mayor, M.; Naef, D.; Pepe, F.; Queloz, D.; Udry, S.; Blecha, A.

    2000-09-01

    Activity related phenomena can induce radial-velocity variations, which can be very important when dealing with extra-solar planet search programmes requiring high-precision radial-velocity measurements. In this paper we present a new chromospheric activity index, SCOR, based on the Ca Ii H line central reemission, and constructed using CORALIE spectra. After one year of measurements, values of SCOR are available for a sub-sample of stars of the Geneva extra-solar planet search programme. After transforming the SCOR values into the Mount-Wilson ``S'' scale we obtained values of the Ca Ii H and K flux corrected from photospheric emission (R'HK) for the stars. The first results are presented, and in particular we focus on the study of the relation between the observed radial-velocity scatter and the chromospheric activity index R'HK, for F, G and K dwarfs. Based on observations collected at the La Silla Observatory, ESO (Chile), with the echelle spectrograph CORALIE at the 1.2-m Euler Swiss telescope

  12. An engineering research and technology program for an evolving, multi-decade Mission to Planet Earth

    Science.gov (United States)

    Sadin, Stanley R.; Johnston, Gordon I.; Hudson, Wayne R.

    1991-01-01

    A study is presented that examines the technological needs of future systems, surveys current and planned activities and highlights significant accomplishments in the research and technology program of the multidecade Mission to Planet Earth (MTPE). Consideration is given to recent program redirection in MTPE, the initiation of the high performance computing and communications program and the potential impact on the technology programs. The technology set is divided into three subsets covering information, observation, and infrastructure technologies.

  13. A Search for Planets and Brown Dwarfs around Post Main Sequence Stars

    Science.gov (United States)

    Otani, Tomomi; Oswalt, Terry D.

    2016-06-01

    The most promising current theory for the origin of subdwarf B (sdB) stars is that they were formed during binary star evolution. This project was conducted to test this hypothesis by searching for companions around six sdB pulsators using the Observed-minus-Calculated (O-C) method. A star’s position in space will wobble due to the gravitational forces of any companion. If it is emitting a periodic signal, the orbital motion of the star around the system’s center of mass causes periodic changes in the light pulse arrival times. O-C diagrams for six sdB pulsators were constructed from several years’ observations, providing useful limits on suspected companions’ minimum masses and semimajor axes. The results were constrained by “period vs. amplitude” and “mass vs. semimajor axis” models to quantify companion masses and semimajor axes that are consistent with the observational data, if any. Two of our targets, V391 Peg and HS0702+6043, are noted in previous publications to have substellar companions. These were used to validate the method used in this research. The results of this study yielded the same masses and semimajor axes for these two stars as the published values, within the uncertainties. Another of the targets, EC20117-4014, is noted in the literature as a binary system containing an sdB and F5V star, however the orbital period and separation were unknown. The new data obtained in this study contain the signal of a companion candidate with a period of 158.01 days. Several possible mass and semimajor axis combinations for the companion are consistent with the observations. One of the other targets in this study displayed preliminary evidence for a companion that will require further observation. Though still a small sample, these results suggest that planets often survive the post-main-sequence evolution of their parent stars.

  14. Limits of Life, Early Evolution and the Search for Habitable Planets

    Science.gov (United States)

    Baross, J.

    2014-03-01

    There are very few natural environments on Earth where life is absent. Microbial life on Earth has proliferated into habitats that span nearly every imaginable physical-chemical variable. Only the availability of liquid water and temperature are known to prevent growth and survival of organisms. The other physical and chemical variables that are thought of as extreme conditions, such as pH, pressure, high concentrations of solutes, damaging radiation, and toxic metals, are life-prohibiting factors for most organisms but not for all. Life has adapted to survive and in some cases grow over the entire terrestrial ranges of these variables. Even under conditions where the availability of water and high temperatures render an environment incapable of supporting active life, these conditions do not necessarily render the environment sterile. Many organisms have adapted mechanisms for long-term survival at temperatures well above their maximum growth temperature, or in a desiccated state. However, there are some combination of physical and chemical conditions, such as high salt and low temperatures, and high salt and high temperatures, for which no known organisms have been found to grow. The first-order priority in the search for extraterrestrial life is the identification of planetary bodies that have measurable characteristics that resemble Earth and meet the habitable conditions that allow the growth of carbon-based life, as we know it. The basic requirements of Earth-life are liquid water, light or chemical energy, and sources of carbon, nitrogen, phosphorus and other micronutrients including more than 20 elements. Does all life resemble Earth life or is it possible that there exists extra-solar Earth-like planets that have evolve successful ecosystems and perhaps even highly complex organisms that bare no resemblance to Earth life at the biochemical level or in the way the biosphere modulates atmospheric conditions?

  15. A High Contrast Imaging Survey of SIM Lite Planet Search Targets

    CERN Document Server

    Tanner, Angelle M; Law, Nicholas M

    2010-01-01

    With the development of extreme high contrast ground-based adaptive optics instruments and space missions aimed at detecting and characterizing Jupiter- and terrestrial-mass planets, it is critical that each target star be thoroughly vetted to determine whether it is a viable target given both the instrumental design and scientific goals of the program. With this in mind, we have conducted a high contrast imaging survey of mature AFGKM stars with the PALAO/PHARO instrument on the Palomar 200 inch telescope. The survey reached sensitivities sufficient to detect brown dwarf companions at separations of > 50 AU. The results of this survey will be utilized both by future direct imaging projects such as GPI, SPHERE and P1640 and indirect detection missions such as SIM Lite. Out of 84 targets, all but one have no close-in (0.45-1") companions and 64 (76%) have no stars at all within the 25" field-of-view. The sensitivity contrasts in the Ks passband ranged from 4.5 to 10 for this set of observations. These stars we...

  16. THREE NEW ECLIPSING WHITE-DWARF-M-DWARF BINARIES DISCOVERED IN A SEARCH FOR TRANSITING PLANETS AROUND M-DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Law, Nicholas M. [Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George St., Toronto, ON M5S 3H4 (Canada); Kraus, Adam L. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Street, Rachel; Fulton, Benjamin J.; Shporer, Avi; Lister, Tim [Las Cumbres Observatory Global Telescope Network, Inc., 6740 Cortona Dr. Suite 102, Santa Barbara, CA 93117 (United States); Hillenbrand, Lynne A.; Baranec, Christoph; Bui, Khanh; Davis, Jack T. C.; Dekany, Richard G.; Kulkarni, S. R.; Ofek, Eran O. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Bloom, Joshua S.; Cenko, S. Bradley; Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Burse, Mahesh P.; Das, H. K. [Inter-University Centre for Astronomy and Astrophysics, Ganeshkhind, Pune-411007 (India); Kasliwal, Mansi M. [Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Nugent, Peter [Computational Cosmology Center, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); and others

    2012-10-01

    We present three new eclipsing white-dwarf/M-dwarf binary systems discovered during a search for transiting planets around M-dwarfs. Unlike most known eclipsing systems of this type, the optical and infrared emission is dominated by the M-dwarf components, and the systems have optical colors and discovery light curves consistent with being Jupiter-radius transiting planets around early M-dwarfs. We detail the PTF/M-dwarf transiting planet survey, part of the Palomar Transient Factory (PTF). We present a graphics processing unit (GPU)-based box-least-squares search for transits that runs approximately 8 Multiplication-Sign faster than similar algorithms implemented on general purpose systems. For the discovered systems, we decompose low-resolution spectra of the systems into white-dwarf and M-dwarf components, and use radial velocity measurements and cooling models to estimate masses and radii for the white dwarfs. The systems are compact, with periods between 0.35 and 0.45 days and semimajor axes of approximately 2 R{sub Sun} (0.01 AU). The M-dwarfs have masses of approximately 0.35 M{sub Sun }, and the white dwarfs have hydrogen-rich atmospheres with temperatures of around 8000 K and have masses of approximately 0.5 M{sub Sun }. We use the Robo-AO laser guide star adaptive optics system to tentatively identify one of the objects as a triple system. We also use high-cadence photometry to put an upper limit on the white-dwarf radius of 0.025 R{sub Sun} (95% confidence) in one of the systems. Accounting for our detection efficiency and geometric factors, we estimate that 0.08%{sub -0.05%}{sup +0.10%} (90% confidence) of M-dwarfs are in these short-period, post-common-envelope white-dwarf/M-dwarf binaries where the optical light is dominated by the M-dwarf. The lack of detections at shorter periods, despite near-100% detection efficiency for such systems, suggests that binaries including these relatively low-temperature white dwarfs are preferentially found at

  17. A Search for Additional Planets in Five of the Exoplanetary Systems Studied by the NASA EPOXI Mission

    CERN Document Server

    Ballard, Sarah; Charbonneau, David; Deming, Drake; Holman, Matthew J; A'Hearn, Michael F; Wellnitz, Dennis D; Barry, Richard K; Kuchner, Marc J; Livengood, Timothy A; Hewagama, Tilak; Sunshine, Jessica M; Hampton, Don L; Lisse, Carey M; Seager, Sara; Veverka, Joseph F

    2011-01-01

    We present time series photometry and constraints on additional planets in five of the exoplanetary systems studied by the EPOCh (Extrasolar Planet Observation and Characterization) component of the NASA EPOXI mission: HAT-P-4, TrES-3, TrES-2, WASP-3, and HAT-P-7. We conduct a search of the high-precision time series for photometric transits of additional planets. We find no candidate transits with significance higher than our detection limit. From Monte Carlo tests of the time series using putative periods from 0.5 days to 7 days, we demonstrate the sensitivity to detect Neptune-sized companions around TrES-2, sub-Saturn-sized companions in the HAT-P-4, TrES-3, and WASP-3 systems, and Saturn-sized companions around HAT-P-7. We investigate in particular our sensitivity to additional transits in the dynamically favorable 3:2 and 2:1 exterior resonances with the known exoplanets: if we assume coplanar orbits with the known planets, then companions in these resonances with HAT-P-4b, WASP-3b, and HAT-P-7b would b...

  18. The Solar Twin Planet Search II. A Jupiter twin around a solar twin

    CERN Document Server

    Bedell, M; Bean, J L; Ramirez, I; Asplund, M; Alves-Brito, A; Casagrande, L; Dreizler, S; Monroe, T; Spina, L; Maia, M Tucci

    2015-01-01

    Through our HARPS radial velocity survey for planets around solar twin stars, we have identified a promising Jupiter twin candidate around the star HIP11915. We characterize this Keplerian signal and investigate its potential origins in stellar activity. Our analysis indicates that HIP11915 hosts a Jupiter-mass planet with a 3600-day orbital period and low eccentricity. Although we cannot definitively rule out an activity cycle interpretation, we find that a planet interpretation is more likely based on a joint analysis of RV and activity index data. The challenges of long-period radial velocity signals addressed in this paper are critical for the ongoing discovery of Jupiter-like exoplanets. If planetary in nature, the signal investigated here represents a very close analog to the solar system in terms of both Sun-like host star and Jupiter-like planet.

  19. Life Beyond the Planet of Origin and Implications for the Search for Life on Mars

    Science.gov (United States)

    Mancinelli, Rocco L.

    2015-01-01

    Outer space is vast, cold, devoid of matter, radiation filled with essentially no gravity. These factors present an environmental challenge for any form of life. Earth's biosphere has evolved for more than 3 billion years shielded from the hostile environment of outer space by the protective blanket of the atmosphere and magnetosphere. Space is a nutritional wasteland with no liquid water and readily available organic carbon. Moving beyond a life's planet of origin requires a means for transport, the ability to withstand transport, and the ability to colonize, thrive and ultimately evolve in the new environment. Can life survive beyond its home planet? The key to answering this question is to identify organisms that first have the ability to withstand space radiation, space vacuum desiccation and time in transit, and second the ability to grow in an alien environment. Within the last 60 years space technology allowed us to transport life beyond Earth's protective shield so we may study, in situ, their responses to selected conditions of space. To date a variety of microbes ranging from viruses, to Bacteria, to Archaea, to Eukarya have been tested in the space environment. Most died instantly, but not all. These studies revealed that ultraviolet radiation is the near-term lethal agent, while hard radiation is the long-term lethal agent when the organism is shielded from ultraviolet radiation. In fact, bacterial spores, halophilic cyanobacteria and Archaea as well as some lichens survive very well if protected from ultraviolet radiation [1]. Some microbes, then, may be able to survive the trip in outer space to Mars on a spacecraft or in a meteorite. Once on Mars can a terrestrial microbe survive? Although the conditions on Mars are not as harsh as those in space, they are not hospitable for a terrestrial microbe. Studies, however, have shown that certain microbes that can survive in space for several years may also be able to survive on Mars if protected from

  20. By Inferno's Light: Characterizing TESS Object of Interest Host Stars for Prioritizing Our Search for Habitable Planets

    Science.gov (United States)

    Unterborn, C. T.; Desch, S. J.; Johnson, J. A.; Panero, W. R.; Teske, J. K.; Hinkel, N. R.

    2016-12-01

    The Earth is unique in our Solar System. It is the only planet known to undergo plate tectonics. It has a magnetic field as result of an outer liquid iron core that protects the surface from Solar radiation. What is not known, however, is whether the Earth is unique among all terrestrial planets outside our Solar System. The population of potentially Earth-like planets will only continue to grow. The TESS mission, launching in 2017, is designed to identify rocky planets around bright, nearby stars across the whole sky. Of the 5,000 potential transit-like signals detected, only 100 will be selected for follow-up spectroscopy. From this subsample, only 50 planets are expected to have both mass and radius measurements, thus allowing for detailed modeling of the planetary interior and potential surface processes. As we search for habitable worlds within this sample, then, understanding which TESS objects of interest (TOI) warrant detailed and time-intensive follow-up observations is of paramount importance. Recent surveys of dwarf planetary host and non-host stars find variations in the major terrestrial planet element abundances (Mg, Fe, Si) of between 10% and 400% of Solar. Additionally, the terrestrial exoplanet record shows planets ranging in size from sub-Mercury to super-Earth. How this stellar compositional diversity is translated into resultant exoplanet physical properties including its mineralogy and structure is not known. Here, we present results of models blending equilibrium condensation sequence computations for determining initial planetesimal composition with geophysical interior calculations for multiple stellar abundance catalogues. This benchmarked and generalized approach allows us to predict the mineralogy and structure of an "average" exoplanet in these planetary systems, thus informing their potential to be "Earth-like." This combination of astro- and geophysical models provides us with a self-consistent method with which to compare planetary

  1. The SOPHIE search for northern extrasolar planets . I. A companion around HD 16760 with mass close to the planet/brown-dwarf transition

    Science.gov (United States)

    Bouchy, F.; Hébrard, G.; Udry, S.; Delfosse, X.; Boisse, I.; Desort, M.; Bonfils, X.; Eggenberger, A.; Ehrenreich, D.; Forveille, T.; Lagrange, A. M.; Le Coroller, H.; Lovis, C.; Moutou, C.; Pepe, F.; Perrier, C.; Pont, F.; Queloz, D.; Santos, N. C.; Ségransan, D.; Vidal-Madjar, A.

    2009-10-01

    We report on the discovery of a substellar companion or a massive Jupiter orbiting the G5V star HD 16760 using the spectrograph SOPHIE installed on the OHP 1.93-m telescope. Characteristics and performances of the spectrograph are presented, as well as the SOPHIE exoplanet consortium program. With a minimum mass of 14.3 {M}_Jup, an orbital period of 465 days and an eccentricity of 0.067, HD 16760b seems to be located just at the end of the mass distribution of giant planets, close to the planet/brown-dwarf transition. Its quite circular orbit supports a formation in a gaseous protoplanetary disk. Based on observations made with SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS/OAMP), France (program 07A.PNP.CONS). Table 2 is also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/505/853

  2. The Hunt for Exomoons with Kepler (HEK): III. The First Search for an Exomoon around a Habitable-Zone Planet

    CERN Document Server

    Kipping, David M; Hartman, Joel; Nesvorny, David; Bakos, Gáspár Á; Schmitt, Allan R; Buchhave, Lars A

    2013-01-01

    Kepler-22b is the first transiting planet to have been detected in the habitable-zone of its host star. At 2.4 Earth radii, Kepler-22b is too large to be considered an Earth-analog, but should the planet host a moon large enough to maintain an atmosphere, then the Kepler-22 system may yet possess a telluric world. Aside from being within the habitable-zone, the target is attractive due to the availability of previously measured precise radial velocities and low intrinsic photometric noise, which has also enabled asteroseismology studies of the star. For these reasons, Kepler-22b was selected as a target-of-opportunity by the 'Hunt for Exomoons with Kepler' (HEK) project. In this work, we conduct a photodynamical search for an exomoon around Kepler-22b leveraging the transits, radial velocities and asteroseismology plus several new tools developed by the HEK project to improve exomoon searches. We find no evidence for an exomoon around the planet and exclude moons of mass >0.5 Earth masses to 95% confidence. B...

  3. Improving Search Properties in Genetic Programming

    Science.gov (United States)

    Janikow, Cezary Z.; DeWeese, Scott

    1997-01-01

    With the advancing computer processing capabilities, practical computer applications are mostly limited by the amount of human programming required to accomplish a specific task. This necessary human participation creates many problems, such as dramatically increased cost. To alleviate the problem, computers must become more autonomous. In other words, computers must be capable to program/reprogram themselves to adapt to changing environments/tasks/demands/domains. Evolutionary computation offers potential means, but it must be advanced beyond its current practical limitations. Evolutionary algorithms model nature. They maintain a population of structures representing potential solutions to the problem at hand. These structures undergo a simulated evolution by means of mutation, crossover, and a Darwinian selective pressure. Genetic programming (GP) is the most promising example of an evolutionary algorithm. In GP, the structures that evolve are trees, which is a dramatic departure from previously used representations such as strings in genetic algorithms. The space of potential trees is defined by means of their elements: functions, which label internal nodes, and terminals, which label leaves. By attaching semantic interpretation to those elements, trees can be interpreted as computer programs (given an interpreter), evolved architectures, etc. JSC has begun exploring GP as a potential tool for its long-term project on evolving dextrous robotic capabilities. Last year we identified representation redundancies as the primary source of inefficiency in GP. Subsequently, we proposed a method to use problem constraints to reduce those redundancies, effectively reducing GP complexity. This method was implemented afterwards at the University of Missouri. This summer, we have evaluated the payoff from using problem constraints to reduce search complexity on two classes of problems: learning boolean functions and solving the forward kinematics problem. We have also

  4. First results of the Kourovka Planet Search: discovery of transiting exoplanet candidates in the first three target fields

    CERN Document Server

    Burdanov, Artem Y; Krushinsky, Vadim V; Popov, Alexander A; Sokov, Evgenii N; Sokova, Iraida A; Rusov, Sergei A; Lyashenko, Artem Yu; Ivanov, Kirill I; Moiseev, Alexei V; Rastegaev, Denis A; Dyachenko, Vladimir V; Balega, Yuri Yu; Baştürk, Özgür; Özavcı, Ibrahim; Puchalski, Damian; Marchini, Alessandro; Naves, Ramon; Shadick, Stan; Bretton, Marc

    2016-01-01

    We present the first results of our search for transiting exoplanet candidates as part of the Kourovka Planet Search (KPS) project. The primary objective of the project is to search for new hot Jupiters which transit their host stars, mainly in the Galactic plane, in the $R_c$ magnitude range of 11 to 14 mag. Our observations were performed with the telescope of the MASTER robotic network, installed at the Kourovka astronomical observatory of the Ural Federal University (Russia), and the Rowe-Ackermann Schmidt Astrograph, installed at the private Acton Sky Portal Observatory (USA). As test observations, we observed three celestial fields of size $2\\times2$ deg$^2$ during the period from 2012 to 2015. As a result, we discovered four transiting exoplanet candidates among the 39000 stars of the input catalogue. In this paper, we provide the description of the project and analyse additional photometric, spectral, and speckle interferometric observations of the discovered transiting exoplanet candidates. Three of ...

  5. The planet Mars in 1973. [international observation programs

    Science.gov (United States)

    Capen, C. F.

    1973-01-01

    Review of several international observation programs of Mars, carried out in 1973 - the last favorable period for Martian observations until the 1980's. The results of the Lowell Observatory International Planetary Patrol Program and of observations by the Association of Lunar and Planetary Observers in France, Japan, Britain and elsewhere are discussed and are shown in diagrams and photographs. Attention is given to the changes in Martian features and to the factors affecting observations adversely.

  6. The HARPS search for Earth-like planets in the habitable zone. I. Very low-mass planets around HD 20794, HD 85512, and HD 192310

    Science.gov (United States)

    Pepe, F.; Lovis, C.; Ségransan, D.; Benz, W.; Bouchy, F.; Dumusque, X.; Mayor, M.; Queloz, D.; Santos, N. C.; Udry, S.

    2011-10-01

    Context. In 2009 we started an intense radial-velocity monitoring of a few nearby, slowly-rotating and quiet solar-type stars within the dedicated HARPS-Upgrade GTO program. Aims: The goal of this campaign is to gather very-precise radial-velocity data with high cadence and continuity to detect tiny signatures of very-low-mass stars that are potentially present in the habitable zone of their parent stars. Methods: Ten stars were selected among the most stable stars of the original HARPS high-precision program that are uniformly spread in hour angle, such that three to four of them are observable at any time of the year. For each star we recorded 50 data points spread over the observing season. The data points consist of three nightly observations with a total integration time of 10 min each and are separated by two hours. This is an observational strategy adopted to minimize stellar pulsation and granulation noise. Results: We present the first results of this ambitious program. The radial-velocity data and the orbital parameters of five new and one confirmed low-mass planets around the stars HD 20794, HD 85512, and HD 192310 are reported and discussed, among which is a system of three super-Earths and one that harbors a 3.6 M⊕-planet at the inner edge of the habitable zone. Conclusions: This result already confirms previous indications that low-mass planets seem to be very frequent around solar-type stars and that this may occur with a frequency higher than 30%. Based on observations made with the HARPS instrument on ESO's 3.6 m telescope at the La Silla Observatory in the frame of the HARPS-Upgrade GTO program ID 086.C-0230.Tables 7-9 (RV data) are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/534/A58

  7. Magnetospheric Emissions from the Planet Orbiting tau Boo: A Multi-Epoch Search

    CERN Document Server

    Lazio, T Joseph W

    2007-01-01

    All of the solar system gas giants produce electron cyclotron masers, driven by the solar wind impinging on their magnetospheres. Extrapolating to the planet orbiting tau Boo, various authors have predicted that it may be within the detection limits of the 4-meter wavelength (74 MHz) system on the Very Large Array. This paper reports three epochs of observations of tau Boo. In no epoch do we detect the planet; various means of determining the upper limit to the emission yield single-epoch limits ranging from 135 to 300 mJy. We develop a likelihood method for multi-epoch observations and use it to constrain various radiation properties of the planet. Assuming that the planet does radiate at our observation wavelength, its typical luminosity must be less than about 10^{16} W, unless its radiation is highly beamed into a solid angle Omega << 1 sr. While within the range of luminosities predicted by various authors for this planet, this value is lower than recent estimates which attempt to take into account...

  8. Mapping the Region in the Nearest Star System to Search for Habitable Planets

    Science.gov (United States)

    Lissauer, Jack J.; Quarles, B.

    2015-01-01

    Circumstellar planets within the alpha Centauri AB star system have been suggested through formation models and recent observations, and ACESat (Belikov et al. AAS Meeting #225, #311.01, 2015) is a proposed space mission designed to directly image Earth-sized planets in the habitable zones of both of these stars. The alpha Centauri system is billions of years old, so planets are only expected to be found in regions where their orbits are long-lived. We evaluate the extent of the regions within the alpha Centauri AB star system where small planets are able to orbit for billion-year timescales and we map the positions in the sky plane where planets on stable orbits about either stellar component may appear. We confirm the qualitative results of Wiegert & Holman (Astron. J. 113, 1445, 1997) regarding the approximate size of the regions of stable orbits, which are larger for retrograde orbits relative to the binary than for prograde orbits. Additionally, we find that mean motion resonances with the binary orbit leave an imprint on the limits of orbital stability, and the effects of the Lidov-Kozai mechanism are also readily apparent. Overall, orbits in the habitable zones near the plane of the binary are stable, whereas high-inclination orbits are short-lived.

  9. Searching for Earth-like planets in this solar system and beyond

    Science.gov (United States)

    Stofan, E. R.

    2014-12-01

    Earth sits in a narrow habitable zone, and its future habitability depends on the actions of those who inhabit the planet today. Earth's complex climate reflects interactions between its interior, surface, oceans, biosphere, atmosphere and its star - our sun. Studying the climates of other planets around our sun - Mars, Venus and Titan - can help us better understand the processes that control climate here on Earth. These three bodies provide compelling targets for future study as we explore beyond our solar system to find Earth-like worlds around other stars.

  10. The Blue Dot Workshop: Spectroscopic Search for Life on Extrasolar Planets

    Science.gov (United States)

    Des Marais, David J. (Editor)

    1997-01-01

    This workshop explored the key questions and challenges associated with detecting life on an extrasolar planet. The final product will be a NASA Conference Publication which includes the abstracts from 21 talks, summaries of key findings, and recommendations for future research. The workshop included sessions on three related topics: the biogeochemistry of biogenic gases in the atmosphere, the chemistry and spectroscopy of planetary atmospheres, and the remote sensing of planetary atmospheres and surfaces. With the observation that planetary formation is probably a common phenomenon, together with the advent of the technical capability to locate and describe extrasolar planets, this research area indeed has an exciting future.

  11. Photometric transit search for planets around cool stars from the western Italian Alps: A pilot study

    CERN Document Server

    Giacobbe, P; Sozzetti, A; Toso, G; Perdoncin, M; Calcidese, P; Bernagozzi, A; Bertolini, E; Lattanzi, M G; Smart, R L

    2012-01-01

    [ABRIDGED] In this study, we set out to a) demonstrate the sensitivity to 50% we would have had >80% chances of detecting planets with P0.5%, corresponding to minimum detectable radii in the range 1.0-2.2 R_E. [ABRIDGED

  12. GMRT search for 150 MHz radio emission from the transiting extrasolar planets HD 189733 b and HD 209458 b

    Science.gov (United States)

    Lecavelier Des Etangs, A.; Sirothia, S. K.; Gopal-Krishna; Zarka, P.

    2011-09-01

    We report a sensitive search for meter-wavelength emission at 150 MHz from two prominent transiting extrasolar planets, HD 189733 b and HD 209458 b. To distinguish any planetary emission from possible stellar or background contributions, we monitored these systems just prior to, during, and after the planet's eclipse behind the host star. No emission was detected from HD 209458 b with a 3σ upper limit of 3.6 mJy. For HD 189733 b we obtain a 3σ upper limit of 2.1 mJy and a marginal 2.7σ detection of ~1900 ± 700 μJy from a direction just 13″ from the star's coordinates (i.e., within the beam), but its association with the planet remains unconfirmed. Thus, the present GMRT observations provide unprecedentedly tight upper limits for meter wavelength emissions from these nearest two transiting-type exoplanets. We point out possible explanations of the non-detections and briefly discuss the resulting constraints on these systems. Data for this observations can be retrieved electronically on the GMRT archive server http://ncra.tifr.res.in/~gmrtarchive and upon request to archive@gmrt.ncra.tifr.res.in.

  13. The HARPS search for southern extra-solar planets XI. Super-Earths (5 & 8 M_Earth) in a 3-planet system

    CERN Document Server

    Udry, S; Delfosse, X; Forveille, T; Mayor, M; Perrier, C; Bouchy, F; Lovis, C; Pepe, F; Queloz, D; Bertaux, J -L

    2007-01-01

    This Letter reports on the detection of two super-Earth planets in the Gl581 system, already known to harbour a hot Neptune. One of the planets has a mass of 5 M_Earth and resides at the ``warm'' edge of the habitable zone of the star. It is thus the known exoplanet which most resembles our own Earth. The other planet has a 7.7 M_Earth mass and orbits at 0.25 AU from the star, close to the ``cold'' edge of the habitable zone. These two new light planets around an M3 dwarf further confirm the formerly tentative statistical trend for i) many more very low-mass planets being found around M dwarfs than around solar-type stars and ii) low-mass planets outnumbering Jovian planets around M dwarfs.

  14. Search for Extra-Terrestrial planets: The DARWIN mission - Target Stars and Array Architectures

    CERN Document Server

    Kaltenegger, L

    2005-01-01

    The DARWIN mission is an Infrared free flying interferometer mission based on the new technique of nulling interferometry. Its main objective is to detect and characterize other Earth-like planets, analyze the composition of their atmospheres and their capability to sustain life, as we know it. DARWIN is currently in definition phase. This PhD work that has been undertaken within the DARWIN team at the European Space Agency (ESA) addresses two crucial aspects of the mission. Firstly, a DARWIN target star list has been established that includes characteristics of the target star sample that will be critical for final mission design, such as, luminosity, distance, spectral classification, stellar variability, multiplicity, location and radius of the star. Constrains were applied as set by planet evolution theory and mission architecture. Secondly, a number of alternative mission architectures have been evaluated on the basis of interferometer response as a function of wavelength, achievable modulation efficienc...

  15. Burrell-Optical-Kepler Survey (BOKS): Exo-planet Search In Cygnus

    Science.gov (United States)

    Proctor, Amanda; Howell, S.; Sherry, W.; Everett, M.; von Braun, K.; Feldmeier, J.; BOKS Consortium

    2007-12-01

    We present the results of >20; continuous days of time series photometric observations of a 1.0 sq. deg field in Cygnus centered on the NASA Kepler Mission field of view. Using the Case Western Burrell Schmidt telescope located at Kitt Peak National Observatory we gathered a dataset containing light curves of roughly 30000 stars between 14planet occultations. We present a summary of our photometric project including many examples of eclipsing binaries and characterization the level and content of stellar variability in this portion of the Kepler field. We will also discuss our potential exo-planet candidates.

  16. Search for giant planets in M67. III. Excess of hot Jupiters in dense open clusters

    Science.gov (United States)

    Brucalassi, A.; Pasquini, L.; Saglia, R.; Ruiz, M. T.; Bonifacio, P.; Leão, I.; Canto Martins, B. L.; de Medeiros, J. R.; Bedin, L. R.; Biazzo, K.; Melo, C.; Lovis, C.; Randich, S.

    2016-07-01

    Since 2008 we used high-precision radial velocity (RV) measurements obtained with different telescopes to detect signatures of massive planets around main-sequence and evolved stars of the open cluster (OC) M67. We aimed to perform a long-term study on giant planet formation in open clusters and determine how this formation depends on stellar mass and chemical composition. A new hot Jupiter (HJ) around the main-sequence star YBP401 is reported in this work. An update of the RV measurements for the two HJ host-stars YBP1194 and YBP1514 is also discussed. Our sample of 66 main-sequence and turnoff stars includes 3 HJs, which indicates a high rate of HJs in this cluster (5.6% for single stars and 4.5%% for the full sample). This rate is much higher than what has been discovered in the field, either with RV surveys or by transits. High metallicity is not a cause for the excess of HJs in M67, nor can the excess be attributed to high stellar masses. When combining this rate with the non-zero eccentricity of the orbits, our results are qualitatively consistent with a HJ formation scenario dominated by strong encounters with other stars or binary companions and subsequent planet-planet scattering, as predicted by N-body simulations. Based on observations collected at the ESO 3.6 m telescope (La Silla), at the 1.93 m telescope of the Observatoire de Haute-Provence (OHP), at the Hobby Eberly Telescope (HET), at the Telescopio Nazionale Galileo (TNG, La Palma) and at the Euler Swiss Telescope.

  17. Cosmologists in Search of Planet Nine: the Case for CMB Experiments

    CERN Document Server

    Cowan, Nicolas B; Kaib, Nathan A

    2016-01-01

    Cosmology experiments at mm-wavelengths may be able to detect Planet Nine if it is the size of Neptune, has an effective temperature of 40 K, and is 700 AU from the Sun. It would appear as a ~30 mJy source at 1 mm (or ~8 mJy at 150 GHz) with a parallax of ~5 arcmin. The challenge will be to distinguish it from the ~4000 foreground asteroids brighter than 30 mJy. Fortunately, asteroids can by identified by looking for sources that move across a resolution element in a matter of hours, orders of magnitude faster than Planet Nine. If Planet Nine is smaller, colder, and/or more distant than expected, then it could be as faint as 1 mJy at 1 mm. There are approximately 1E6 asteroids this bright, making many cosmology experiments confusion limited for moving sources. Nonetheless, it may still be possible to find the proverbial needle in the haystack using a matched filter. This would require mm telescopes with high angular resolution and high sensitivity in order to alleviate confusion and to enable the identificati...

  18. Numerical search for a potential planet sculpting the young disc of HD 115600

    Science.gov (United States)

    Thilliez, E.; Maddison, S. T.

    2017-01-01

    Radial and azimuthal features (such as disc offsets and eccentric rings) seen in high-resolution images of debris discs provide us with the unique opportunity of finding potential planetary companions that betray their presence by gravitationally sculpting such asymmetric features. The young debris disc around HD 115600, imaged recently by the Gemini Planet Imager, is such a disc with an eccentricity e ˜ 0.1-0.2 and a projected offset from the star of ˜4 au. Using our modified N-body code that incorporates radiation forces, we first aim to determine the orbit of a hidden planetary companion potentially responsible for shaping the disc. We run a suite of simulations covering a broad range of planetary parameters using a Monte Carlo Markov Chain sampling method and create synthetic images from which we extract the geometric disc parameters to be compared with the observed and model-derived quantities. We then repeat the study using a traditional grid to explore the planetary parameter space and then aim to compare the efficiency of both sampling methods. We find a planet of 7.8 MJ orbiting at 30 au with an eccentricity of e = 0.2 to be the best fit to the observations of HD 115600. Technically, such planet has a contrast detectable by direct imaging, however the system's orientation does not favour such detection. In this study, at equal number of explored planetary configurations, the Monte Carlo Markov Chain not only converges faster but provides a better fit than a traditional grid.

  19. The SOPHIE search for northern extrasolar planets. XI. Three new companions and an orbit update: Giant planets in the habitable zone

    Science.gov (United States)

    Díaz, R. F.; Rey, J.; Demangeon, O.; Hébrard, G.; Boisse, I.; Arnold, L.; Astudillo-Defru, N.; Beuzit, J.-L.; Bonfils, X.; Borgniet, S.; Bouchy, F.; Bourrier, V.; Courcol, B.; Deleuil, M.; Delfosse, X.; Ehrenreich, D.; Forveille, T.; Lagrange, A.-M.; Mayor, M.; Moutou, C.; Pepe, F.; Queloz, D.; Santerne, A.; Santos, N. C.; Sahlmann, J.; Ségransan, D.; Udry, S.; Wilson, P. A.

    2016-07-01

    We report the discovery of three new substellar companions to solar-type stars, HD 191806, HD 214823, and HD 221585, based on radial velocity measurements obtained at the Haute-Provence Observatory. Data from the SOPHIE spectrograph are combined with observations acquired with its predecessor, ELODIE, to detect and characterise the orbital parameters of three new gaseous giant and brown dwarf candidates. Additionally, we combine SOPHIE data with velocities obtained at the Lick Observatory to improve the parameters of an already known giant planet companion, HD 16175 b. Thanks to the use of different instruments, the data sets of all four targets span more than ten years. Zero-point offsets between instruments are dealt with using Bayesian priors to incorporate the information we possess on the SOPHIE/ELODIE offset based on previous studies. The reported companions have orbital periods between three and five years and minimum masses between 1.6 MJup and 19 MJup. Additionally, we find that the star HD 191806 is experiencing a secular acceleration of over 11 m s-1 per year, potentially due to an additional stellar or substellar companion. A search for the astrometric signature of these companions was carried out using Hipparcos data. No orbit was detected, but a significant upper limit to the companion mass can be set for HD 221585, whose companion must be substellar. With the exception of HD 191806 b, the companions are located within the habitable zone of their host star. Therefore, satellites orbiting these objects could be a propitious place for life to develop. Based on observations collected with the SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS), France by the SOPHIE Consortium (programme 07A.PNP.CONS to 15A.PNP.CONS).

  20. High Ph, Ammonia Toxicity, and the Search for Life on the Jovian Planets

    Science.gov (United States)

    Deal, P. H.; Souza, K. A.; Mack, H. M.

    1975-01-01

    The effects of pH and ammonia concentration were studied separately, where possible, on a variety of organisms, including some isolated from natural environments of high pH and/or ammonia concentration. Escherichia coli and Bacillus subtilis are both extremely sensitive to ammonia. An aerobic organism (growth up to pH 11.4) from an alkaline spring is more resistant, but exhibits a toxic response to ammonia at a pH much lower than its maximum for growth. The greatest ammonia resistance has been found in an unidentified organism growing at near neutral pH. Even in this case, however, urvival at ammonia concentrations reasonably expected on the Jovian planets is measured in hours. This is two to three orders of magnitude longer than for E. coli. Results support the tentative conclusion that contamination of the Jovian planets with terrestrial organisms that can grow is unlikely. However, the range of toxic response noted, coupled with the observation that terrestrial life has not been exposed to high ammonia concentrations for millions of years, suggests that adaptation to greater ammonia tolerance may be possible.

  1. Searching for Star-Planet interactions within the magnetosphere of HD 189733

    CERN Document Server

    Fares, R; Moutou, C; Jardine, M M; Griessmeier, J -M; Zarka, P; Shkolnik, E L; Bohlender, D; Catala, C; Cameron, A C

    2010-01-01

    HD 189733 is a K2 dwarf, orbited by a giant planet at 8.8 stellar radii. In order to study magnetospheric interactions between the star and the planet, we explore the large-scale magnetic field and activity of the host star. We collected spectra using the ESPaDOnS and the NARVAL spectropolarimeters, installed at the 3.6-m Canada-France-Hawaii telescope and the 2-m Telescope Bernard Lyot at Pic du Midi, during two monitoring campaigns (June 2007 and July 2008). HD 189733 has a mainly toroidal surface magnetic field, having a strength that reaches up to 40 G. The star is differentially rotating, with latitudinal angular velocity shear of domega = 0.146 +- 0.049 rad/d, corresponding to equatorial and polar periods of 11.94 +- 0.16 d and 16.53 +- 2.43 d respectively. The study of the stellar activity shows that it is modulated mainly by the stellar rotation (rather than by the orbital period or the beat period between the stellar rotation and the orbital periods). We report no clear evidence of magnetospheric int...

  2. Searching for Earth-mass planets around $\\alpha$ Centauri: precise radial velocities from contaminated spectra

    CERN Document Server

    Bergmann, Christoph; Hearnshaw, John B; Wittenmyer, Robert A; Wright, Duncan J

    2014-01-01

    This work is part of an ongoing project which aims to detect terrestrial planets in our neighbouring star system $\\alpha$ Centauri using the Doppler method. Owing to the small angular separation between the two components of the $\\alpha$ Cen AB binary system, the observations will to some extent be contaminated with light coming from the other star. We are accurately determining the amount of contamination for every observation by measuring the relative strengths of the H-$\\alpha$ and NaD lines. Furthermore, we have developed a modified version of a well established Doppler code that is modelling the observations using two stellar templates simultaneously. With this method we can significantly reduce the scatter of the radial velocity measurements due to spectral cross-contamination and hence increase our chances of detecting the tiny signature caused by potential Earth-mass planets. After correcting for the contamination we achieve radial velocity precision of $\\sim 2.5\\,\\mathrm{m\\,s^{-1}}$ for a given night...

  3. Removing Activity-Related Radial Velocity Noise to Improve Extrasolar Planet Searches

    Science.gov (United States)

    Saar, Steven; Lindstrom, David M. (Technical Monitor)

    2004-01-01

    We have made significant progress towards the proposal goals of understanding the causes and effects of magnetic activity-induced radial velocity (v_r) jitter and developing methods for correcting it. In the process, we have also made some significant discoveries in the fields of planet-induced stellar activity, planet detection methods, M dwarf convection, starspot properties, and magnetic dynamo cycles. We have obtained super high resolution (R approximately 200,000), high S / N (greater than 300) echelle study of joint line bisector and radial velocity variations using the McDonald 2-D coude. A long observing run in October 2002 in particular was quite successful (8 clear nights). We now have close to three years of data, which begins to sample a good fraction of the magnetic cycle timescales for some of our targets (e.g., kappa Ceti; P_cyc = 5.6 yrs). This will be very helpful in unraveling the complex relationships between plage and radial velocity (v-r) changes which we have uncovered. Preliminary analysis (Saar et al. 2003) of the data in hand, reveals correlations between median line bisector displacement and v_r. The correlation appears to be specific the the particular star being considered, probably since it is a function of both spectral type and rotation rate. Further analysis and interpretation will be in the context of evolving plage models and is in progress.

  4. Search for giant planets in M67 III: excess of hot Jupiters in dense open clusters

    CERN Document Server

    Brucalassi, A; Saglia, R; Ruiz, M T; Bonifacio, P; Leao, I; Martins, B L Canto; de Medeiros, J R; Bedin, L R; Biazzo, K; Melo, C; Lovis, C; Randich, S

    2016-01-01

    Since 2008 we used high-precision radial velocity (RV) measurements obtained with different telescopes to detect signatures of massive planets around main-sequence and evolved stars of the open cluster (OC) M67. We aimed to perform a long-term study on giant planet formation in open clusters and determine how this formation depends on stellar mass and chemical composition. A new hot Jupiter (HJ) around the main-sequence star YBP401 is reported in this work. An update of the RV measurements for the two HJ host-stars YBP1194 and YBP1514 is also discussed. Our sample of 66 main-sequence and turnoff stars includes 3 HJs, which indicates a high rate of HJs in this cluster (~5.6% for single stars and ~4.5% for the full sample ). This rate is much higher than what has been discovered in the field, either with RV surveys or by transits. High metallicity is not a cause for the excess of HJs in M67, nor can the excess be attributed to high stellar masses. When combining this rate with the non-zero eccentricity of the o...

  5. Inferring statistics of planet populations by means of automated microlensing searches

    CERN Document Server

    Dominik, M; Horne, K; Tsapras, Y; Street, R A; Wyrzykowski, L; Hessman, F V; Hundertmark, M; Rahvar, S; Wambsganss, J; Scarpetta, G; Bozza, V; Novati, S Calchi; Mancini, L; Masi, G; Teuber, J; Hinse, T C; Steele, I A; Burgdorf, M J; Kane, S

    2008-01-01

    (abridged) The study of other worlds is key to understanding our own, and not only provides clues to the origin of our civilization, but also looks into its future. Rather than in identifying nearby systems and learning about their individual properties, the main value of the technique of gravitational microlensing is in obtaining the statistics of planetary populations within the Milky Way and beyond. Only the complementarity of different techniques currently employed promises to yield a complete picture of planet formation that has sufficient predictive power to let us understand how habitable worlds like ours evolve, and how abundant such systems are in the Universe. A cooperative three-step strategy of survey, follow-up, and anomaly monitoring of microlensing targets, realized by means of an automated expert system and a network of ground-based telescopes is ready right now to be used to obtain a first census of cool planets with masses reaching even below that of Earth orbiting K and M dwarfs in two dist...

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

    Science.gov (United States)

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

    2016-10-01

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

  7. The SOPHIE search for northern extrasolar planets. V. Follow-up of ELODIE candidates: Jupiter-analogs around Sun-like stars

    Science.gov (United States)

    Boisse, I.; Pepe, F.; Perrier, C.; Queloz, D.; Bonfils, X.; Bouchy, F.; Santos, N. C.; Arnold, L.; Beuzit, J.-L.; Díaz, R. F.; Delfosse, X.; Eggenberger, A.; Ehrenreich, D.; Forveille, T.; Hébrard, G.; Lagrange, A.-M.; Lovis, C.; Mayor, M.; Moutou, C.; Naef, D.; Santerne, A.; Ségransan, D.; Sivan, J.-P.; Udry, S.

    2012-09-01

    We present radial-velocity measurements obtained in one of a number of programs underway to search for extrasolar planets with the spectrograph SOPHIE at the 1.93-m telescope of the Haute-Provence Observatory. Targets were selected from catalogs observed with ELODIE, which had been mounted previously at the telescope, in order to detect long-period planets with an extended database close to 15 years. Two new Jupiter-analog candidates are reported to orbit the bright stars HD 150706 and HD 222155 in 16.1 yr and 10.9 yr at 6.7-1.4+4.0 AU and 5.1-0.7+0.6 AU, and to have minimum masses of 2.71-0.66+1.14 MJup and 1.90-0.53+0.67 MJup, respectively. Using the measurements from ELODIE and SOPHIE, we refine the parameters of the long-period planets HD 154345b and HD 89307b, and publish the first reliable orbit for HD 24040b. This last companion has a minimum mass of 4.01 ± 0.49 MJup orbiting its star in 10.0 yr at 4.92 ± 0.38 AU. Moreover, the data provide evidence of a third bound object in the HD 24040 system. With a surrounding dust debris disk, HD 150706 is an active G0 dwarf for which we partially corrected the effect of the stellar spot on the SOPHIE radial-velocities. In contrast, HD 222155 is an inactive G2V star. In the SOPHIE measurements, an instrumental effect could be characterized and partly corrected. On the basis of the previous findings of Lovis and collaborators and since no significant correlation between the radial-velocity variations and the activity index are found in the SOPHIE data, these variations are not expected to be only due to stellar magnetic cycles. Finally, we discuss the main properties of this new population of long-period Jupiter-mass planets, which for the moment consists of fewer than 20 candidates. These stars are preferential targets either for direct-imaging or astrometry follow-up surveys to constrain the system parameters and for higher-precision radial-velocity searches for lower mass planets, aiming to find a solar system twin

  8. First results of the Kourovka Planet Search: discovery of transiting exoplanet candidates in the first three target fields

    Science.gov (United States)

    Burdanov, Artem Y.; Benni, Paul; Krushinsky, Vadim V.; Popov, Alexander A.; Sokov, Evgenii N.; Sokova, Iraida A.; Rusov, Sergei A.; Lyashenko, Artem Yu.; Ivanov, Kirill I.; Moiseev, Alexei V.; Rastegaev, Denis A.; Dyachenko, Vladimir V.; Balega, Yuri Yu.; Baştürk, Özgür; Özavcı, Ibrahim; Puchalski, Damian; Marchini, Alessandro; Naves, Ramon; Shadick, Stan; Bretton, Marc

    2016-10-01

    We present the first results of our search for transiting exoplanet candidates as part of the Kourovka Planet Search (KPS) project. The primary objective of the project is to search for new hot Jupiters which transit their host stars, mainly in the Galactic plane, in the Rc magnitude range of 11-14 mag. Our observations were performed with the telescope of the MASTER robotic network, installed at the Kourovka astronomical observatory of the Ural Federal University (Russia), and the Rowe-Ackermann Schmidt Astrograph, installed at the private Acton Sky Portal Observatory (USA). As test observations, we observed three celestial fields of size 2 × 2 deg2 during the period from 2012 to 2015. As a result, we discovered four transiting exoplanet candidates among the 39 000 stars of the input catalogue. In this paper, we provide the description of the project and analyse additional photometric, spectral, and speckle interferometric observations of the discovered transiting exoplanet candidates. Three of the four transiting exoplanet candidates are most likely astrophysical false positives, while the nature of the fourth (most promising) candidate remains to be ascertained. Also, we propose an alternative observing strategy that could increase the project's exoplanet haul.

  9. The planet search programme at the ESO CES and HARPS. IV. The search for Jupiter analogues around solar-like stars

    CERN Document Server

    Zechmeister, M; Endl, M; Curto, G Lo; Hartman, H; Nilsson, H; Henning, T; Hatzes, A P; Cochran, W D

    2012-01-01

    In 1992 we began a precision radial velocity (RV) survey for planets around solar-like stars with the Coude Echelle Spectrograph and the Long Camera (CES LC) at the 1.4 m telescope in La Silla (Chile). We have continued the survey with the upgraded CES Very Long Camera (VLC) and HARPS, both at the 3.6 m telescope, until 2007. The observations for 31 stars cover a time span of up to 15 years and the RV precision permit a search for Jupiter analogues. We perform a joint analysis for variability, trends, periodicities, and Keplerian orbits and compute detection limits. Moreover, the HARPS RVs are analysed for correlations with activity indicators (CaII H&K and CCF shape). We achieve a long-term RV precision of 15 m/s (CES+LC, 1992-1998), 9 m/s (CES+VLC, 1999-2006), and 2.8 m/s (HARPS, 2003-2009, including archive data), resp. This enables us to confirm the known planets around Iota Hor, HR 506, and HR 3259. A steady RV trend for Eps Ind A can be explained by a planetary companion. On the other hand, we find ...

  10. Hide and Seek: Radial-velocity searches for planets around active stars

    Science.gov (United States)

    Haywood, Raphaelle

    2017-01-01

    The ultimate obstacle to determining the masses of small, rocky exoplanets through radial-velocity (RV) monitoring is the intrinsic variability of the host stars themselves. For my PhD, I developed an intuitive and robust data analysis framework in which the activity-induced variations are modelled with a Gaussian process that has the frequency structure of the stellar magnetic activity. This allowed me to determine precise and accurate masses of the planets in the CoRoT-7, Kepler-78 and Kepler-10 systems. In parallel, I explored the physical origin of activity-induced RV variations of our best-known star: the Sun. I conducted the first systematic RV campaign of the Sun seen as an exoplanet host star using the 3.6m/HARPS spectrograph, by observing sunlight reflected off the bright asteroid 4/Vesta. I used images from the Solar Dynamics Observatory to reconstruct the RV signals incurred by individual surface features such as sunspots, faculae and granulation. I found that the activity-induced RV variations are driven by the suppression of convective blueshift arising dominantly from the presence of faculae. I also identified the full-disc magnetic flux as an excellent proxy for activity-induced RV variations.I am now pursuing my solar investigations using Sun-as-a-star RV observations acquired with the new solar telescope feed at HARPS-N. In particular, I am investigating the impact of magnetic surface features on the shapes of the spectral line profiles, rather than on the RVs themselves (which are a single moment of these lines). This work is key to developing physically-driven, better-tailored models for activity-induced RV variations, in preparation for the potentially habitable, Earth-like planets to be discovered and characterised in the coming years with TESS and GMT/G-CLEF.This work was funded by the Science and Technology Facilities Council in the United Kingdom and the John Templeton Foundation.

  11. SEARCHING FOR PLANETS IN HOLEY DEBRIS DISKS WITH THE APODIZING PHASE PLATE

    Energy Technology Data Exchange (ETDEWEB)

    Meshkat, Tiffany; Kenworthy, Matthew A. [Sterrewacht Leiden, P.O. Box 9513, Niels Bohrweg 2, 2300 RA Leiden (Netherlands); Bailey, Vanessa P.; Su, Kate Y. L.; Hinz, Philip M.; Smith, Paul S. [Steward Observatory, Department of Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States); Mamajek, Eric E. [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627-0171 (United States)

    2015-02-10

    We present our first results from a high-contrast imaging search for planetary mass companions around stars with gapped debris disks, as inferred from the stars' bright infrared excesses. For the six considered stars, we model the disks' unresolved infrared spectral energy distributions in order to derive the temperature and location of the disk components. With VLT/NaCo Apodizing Phase Plate coronagraphic L'-band imaging, we search for planetary mass companions that may be sculpting the disks. We detect neither disks nor companions in this sample, confirmed by comparing plausible point sources with archival data. In order to calculate our mass sensitivity limit, we revisit the stellar age estimates. One target, HD 17848, at 540 ± 100 Myr old is significantly older than previously estimated. We then discuss our high-contrast imaging results with respect to the disk properties.

  12. Searching for Planets in Holey Debris Disks with the Apodizing Phase Plate

    CERN Document Server

    Meshkat, Tiffany; Su, Kate Y L; Kenworthy, Matthew A; Mamajek, Eric E; Hinz, Philip M; Smith, Paul S

    2014-01-01

    We present our first results from a high-contrast imaging search for planetary mass companions around stars with gapped debris disks, as inferred from the stars' bright infrared excesses. For the six considered stars, we model the disks' unresolved infrared spectral energy distributions (SEDs) in order to derive the temperature and location of the disk components. With VLT/NaCo Apodizing Phase Plate coronagraphic L'-band imaging, we search for planetary mass companions that may be sculpting the disks. We detect neither disks nor companions in this sample, confirmed by comparing plausible point sources with archival data. In order to calculate our mass sensitivity limit, we revisit the stellar age estimates. One target, HD 17848, at 540$\\pm$100 Myr old is significantly older than previously estimated. We then discuss our high-contrast imaging results with respect to the disk properties.

  13. The Penn State - Torun Centre for Astronomy Planet Search stars. II. Lithium abundance analysis of the Red Giant Clump sample

    CERN Document Server

    Adamow, M; Villaver, E; Wolszczan, A; Nowak, G

    2014-01-01

    Using the sample of 348 stars from the PennState-Torun Centre for Astronomy Planet Search, for which uniformly determined atmospheric parameters are available, with chemical abundances and rotational velocities presented here, we investigate various channels of Li enrichment in giants. Our work is based on the HET/HRS spectra. The A(Li) was determined from the 670.8nm line, while we use a more extended set of lines for alpha-elements abundances. In a series of K-S tests, we compare Li-rich giants with other stars in the sample. We also use available IR photometric and kinematical data in search for evidence of mass-loss. We investigate properties of the most Li-abundant giants in more detail by using multi-epoch precise radial velocities. We present Li and alpha-elements abundances, as well as vsini for 348 stars. We detected Li in 92 stars, of which 82 are giants. 11 of them show significant Li abundance A(Li)>1.4 and 7 of them are Li-overabundant objects, according to criterion of A(Li)>1.5 and their locati...

  14. Numerical search for a potential planet sculpting the young disc of HD 115600

    CERN Document Server

    Thilliez, E

    2016-01-01

    Radial and azimuthal features (such as disc offsets and eccentric rings) seen in high resolution images of debris discs, provide us with the unique opportunity of finding potential planetary companions which betray their presence by gravitationally sculpting such asymmetric features. The young debris disc around HD 115600, imaged recently by the Gemini Planet Imager, is such a disc with an eccentricity 0.1

  15. Detection of Potential Transit Signals in 17 Quarters of Kepler Data: Results of the Final Kepler Mission Transiting Planet Search (DR25)

    CERN Document Server

    Twicken, Joseph D; Seader, Shawn E; Tenenbaum, Peter; Smith, Jeffrey C; Brownston, Lee S; Burke, Christopher J; Catanzarite, Joseph H; Clarke, Bruce D; Cote, Miles T; Girouard, Forrest R; Klaus, Todd C; Li, Jie; McCauliff, Sean D; Morris, Robert L; Wohler, Bill; Campbell, Jennifer R; Uddin, Akm Kamal; Zamudio, Khadeejah A; Sabale, Anima; Bryson, Steven T; Caldwell, Douglas A; Christiansen, Jessie L; Coughlin, Jeffrey L; Haas, Michael R; Henze, Christopher E; Sanderfer, Dwight T; Thompson, Susan E

    2016-01-01

    We present results of the final Kepler Data Processing Pipeline search for transiting planet signals in the full 17-quarter primary mission dataset. The search includes a total of 198,709 stellar targets of which 112,046 were observed in all 17 quarters and 86,663 in fewer than 17 quarters. We report on 17,230 targets for which at least one transit signature is identified that meets the specified detection criteria: periodicity, minimum of three observed transit events, detection statistic (i.e., signal to noise ratio) in excess of the search threshold, and passing grade on three statistical transit consistency tests. Light curves for which a transit signal is identified are iteratively searched for additional signatures after a limb-darkened transiting planet model is fitted to the data and transit events are removed. The search for additional planets adds 16,802 transit signals for a total of 34,032; this far exceeds the number of transit signatures identified in prior pipeline runs. There was a strategic e...

  16. Development of a Concurrent Tree Search Program.

    Science.gov (United States)

    1982-10-01

    rtfiia intelience Evefonith good0 heriti funcions Ohe tieiPAESo 4 sarch.I~ AtErC AM discussing (i concuret p o roramn issue asI bEUIYCAkgroundhi...tree search, is fundamental to the field of artificial intelligence. Even with good heuristic functions, the time it takes on a single processor to...fundamental to the field of artificial intelligence. Even with good heuristic functions, the time it takes on a single processor to solve progressively

  17. Genomic Signal Search by Dynamic Programming

    Institute of Scientific and Technical Information of China (English)

    ZHENG Wei-Mou

    2003-01-01

    A general and flexible multi-motif model is proposed based on dynamic programming. By extending theGibbs sampler to the dynamic programming and introducing temperature, an efficient algorithm is developed. Branchpoint signalsequences and translation initiation sequences extracted from the rice genome are then examined.

  18. On the Search for Transits of the Planets Orbiting GL 876 [PREPRINT

    Science.gov (United States)

    2006-08-13

    their radii would also give clues to their interior structure (see Charbon - neau et al. 2006). Finally, the Gl 876 system with its strongly gravita...work supported by the National Aeronautics and Space Administration under Grant NNG04GN30G issued through the Origins of So- lar Systems Program to GL

  19. A Matheuristic Approach Combining Local Search and Mathematical Programming

    Directory of Open Access Journals (Sweden)

    Carolina Lagos

    2016-01-01

    Full Text Available A novel matheuristic approach is presented and tested on a well-known optimisation problem, namely, capacitated facility location problem (CFLP. The algorithm combines local search and mathematical programming. While the local search algorithm is used to select a subset of promising facilities, mathematical programming strategies are used to solve the subproblem to optimality. Proposed local search is influenced by instance-specific information such as installation cost and the distance between customers and facilities. The algorithm is tested on large instances of the CFLP, where neither local search nor mathematical programming is able to find good quality solutions within acceptable computational times. Our approach is shown to be a very competitive alternative to solve large-scale instances for the CFLP.

  20. Precise Infrared Radial Velocities from Keck/NIRSPEC and the Search for Young Planets

    CERN Document Server

    Bailey, John I; Blake, Cullen H; Charbonneau, Dave; Barman, Travis S; Tanner, Angelle M; Torres, Guillermo

    2012-01-01

    We present a high-precision infrared radial velocity study of late-type stars using spectra obtained with NIRSPEC at the W. M. Keck Observatory. Radial velocity precisions of 50 m/s are achieved for old field mid-M dwarfs using telluric features for precise wavelength calibration. Using this technique, 20 young stars in the {\\beta} Pic (age ~12 Myr) and TW Hya (age ~8 Myr) Associations were monitored over several years to search for low mass companions; we also included the chromospherically active field star GJ 873 (EV Lac) in this survey. Based on comparisons with previous optical observations of these young active stars, radial velocity measurements at infrared wavelengths mitigate the radial velocity noise caused by star spots by a factor of ~3. Nevertheless, star spot noise is still the dominant source of measurement error for young stars at 2.3 {\\mu}m, and limits the precision to ~77 m/s for the slowest rotating stars (v sin i 12 km/s). The observations reveal both GJ 3305 and TWA 23 to be single-lined...

  1. Development of lower Triassic wrinkle structures: implications for the search for life on other planets.

    Science.gov (United States)

    Mata, Scott A; Bottjer, David J

    2009-11-01

    Wrinkle structures are microbially mediated sedimentary structures that are a common feature of Proterozoic and earliest Phanerozoic siliciclastic seafloors on Earth and occur only rarely in post-Cambrian strata. These macroscopic microbially induced sedimentary structures are readily identifiable at the outcrop scale, and their recognition on other planetary bodies by landed missions may suggest the presence of past microbial life. Wrinkle structures of the Lower Triassic (Spathian) Virgin Limestone Member of the Moenkopi Formation in the western United States record an occurrence of widespread microbialite formation in the wake of the end-Permian mass extinction, the largest biotic crisis of the Phanerozoic. Wrinkle structures occur on proximal sandy tempestites deposited within the offshore transition. Storm layers appear to have been rapidly colonized by microbial mats and were subsequently buried by mud during fair-weather conditions. Wrinkle structures exhibit flat-topped crests and sinuous troughs, with associated mica grains oriented parallel to bedding, suggestive of trapping and binding activity. Although Lower Triassic wrinkle structures postdate the widespread occurrence of these features during the Proterozoic and Cambrian, they exhibit many of the same characteristics and environmental trends, which suggests a conservation of microbial formational and preservational processes in subtidal siliciclastic settings on Earth from the Precambrian into the Phanerozoic. In the search for extraterrestrial life, it may be these conservative characteristics that prove to be the most useful and robust for recognizing microbial features on other planetary bodies, and may add to an ever-growing foundation of knowledge for directing future explorations aimed at seeking out macroscopic microbial signatures.

  2. Testing planet formation theories with Giant stars

    CERN Document Server

    Pasquini, Luca; Hatzes, A; Setiawan, J; Girardi, L; da Silva, L; De Medeiros, J R

    2008-01-01

    Planet searches around evolved giant stars are bringing new insights to planet formation theories by virtue of the broader stellar mass range of the host stars compared to the solar-type stars that have been the subject of most current planet searches programs. These searches among giant stars are producing extremely interesting results. Contrary to main sequence stars planet-hosting giants do not show a tendency of being more metal rich. Even if limited, the statistics also suggest a higher frequency of giant planets (at least 10 %) that are more massive compared to solar-type main sequence stars. The interpretation of these results is not straightforward. We propose that the lack of a metallicity-planet connection among giant stars is due to pollution of the star while on the main sequence, followed by dilution during the giant phase. We also suggest that the higher mass and frequency of the planets are due to the higher stellar mass. Even if these results do not favor a specific formation scenario, they su...

  3. The HARPS search for southern extra-solar planets. XXVII. Up to seven planets orbiting HD 10180: probing the architecture of low-mass planetary systems

    CERN Document Server

    Lovis, C; Mayor, M; Udry, S; Benz, W; Bertaux, J -L; Bouchy, F; Correia, A C M; Laskar, J; Curto, G Lo; Mordasini, C; Pepe, F; Queloz, D; Santos, N C

    2010-01-01

    Context. Low-mass extrasolar planets are presently being discovered at an increased pace by radial velocity and transit surveys, opening a new window on planetary systems. Aims. We are conducting a high-precision radial velocity survey with the HARPS spectrograph which aims at characterizing the population of ice giants and super-Earths around nearby solar-type stars. This will lead to a better understanding of their formation and evolution, and yield a global picture of planetary systems from gas giants down to telluric planets. Methods. Progress has been possible in this field thanks in particular to the sub-m/s radial velocity precision achieved by HARPS. We present here new high-quality measurements from this instrument. Results. We report the discovery of a planetary system comprising at least five Neptune-like planets with minimum masses ranging from 12 to 25 M_Earth, orbiting the solar-type star HD 10180 at separations between 0.06 and 1.4 AU. A sixth radial velocity signal is present at a longer perio...

  4. Planet Hunters VI: The First Kepler Seven Planet Candidate System and 13 Other Planet Candidates from the Kepler Archival Data

    CERN Document Server

    Schmitt, Joseph R; Fischer, Debra A; Jek, Kian J; Moriarty, John C; Boyajian, Tabetha S; Schwamb, Megan E; Lintott, Chris; Smith, Arfon M; Parrish, Michael; Schawinski, Kevin; Lynn, Stuart; Simpson, Robert; Omohundro, Mark; Winarski, Troy; Goodman, Samuel J; Jebson, Tony; Lacourse, Daryll

    2013-01-01

    We report the discovery of 14 new transiting planet candidates in the Kepler field from the Planet Hunters citizen science program. None of these candidates overlap with Kepler Objects of Interest (KOIs), and five of the candidates were missed by the Kepler Transit Planet Search (TPS) algorithm. The new candidates have periods ranging from 124-904 days, eight residing in their host star's habitable zone (HZ) and two (now) in multiple planet systems. We report the discovery of one more addition to the six planet candidate system around KOI-351, marking the first seven planet candidate system from Kepler. Additionally, KOI-351 bears some resemblance to our own solar system, with the inner five planets ranging from Earth to mini-Neptune radii and the outer planets being gas giants; however, this system is very compact, with all seven planet candidates orbiting $\\lesssim 1$ AU from their host star. We perform a numerical integration of the orbits and show that the system remains stable for over 100 million years....

  5. Search for exoplanet around northern circumpolar stars - Four planets around HD 11755, HD 12648, HD 24064, and 8 Ursae Minoris

    CERN Document Server

    Lee, B -C; Lee, S -M; Jeong, G; Oh, H -I; Han, I; Lee, J W; Lee, C -U; Kim, S -L; Kim, K -M

    2015-01-01

    Aims. This program originated as the north pole region extension of the established exoplanet survey using 1.8 m telescope at Bohyunsan Optical Astronomy Observatory (BOAO). The aim of our paper is to find exoplanets in northern circumpolar stars with a precise radial velocity (RV) survey. Methods. We have selected about 200 northern circumpolar stars with the following criteria: Dec. > 70 degree, 0.6 < B-V < 1.6, HIPPARCOS_scat < 0.05 magnitude, and 5.0 < mv < 7.0. The high-resolution, fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) was used for the RV survey. Chromospheric activities, the HIPPARCOS photometry, and line bisectors were analyzed to exclude other causes for the RV variations. Results. In 2010, we started to monitor the candidates and have completed initial screening for all stars for the last five years. We present the detection of four new exoplanets. Stars HD 11755, HD 12648, HD 24064, and 8 UMi all show evidence for giant planets in Keplerian motion. The companion ...

  6. Planet Hunters X: Searching for Nearby Neighbors of 75 Planet and Eclipsing Binary Candidates from the K2 Kepler extended mission

    CERN Document Server

    Schmitt, Joseph R; Wang, Ji; Fischer, Debra A; Kristiansen, Martti H; LaCourse, Daryll M; Gagliano, Robert; Tan, Arvin Joseff V; Schwengeler, Hans Martin; Omohundro, Mark R; Venner, Alexander; Terentev, Ivan; Schmitt, Allan R; Jacobs, Thomas L; Winarski, Troy; Sejpka, Johann; Jek, Kian J; Boyajian, Tabetha S; Brewer, John M; Ishikawa, Sascha T; Lintott, Chris; Lynn, Stuart; Schawinski, Kevin; Weiksnar, Alex

    2016-01-01

    We present high resolution observations of a sample of 75 K2 targets from Campaigns 1-3 using speckle interferometry on the Southern Astrophysical Research (SOAR) telescope and adaptive optics (AO) imaging at the Keck II telescope. The median SOAR $I$-band and Keck $K_s$-band detection limits at 1'' were $\\Delta m_{I}=4.4$ mag and $\\Delta m_{K_s}=6.1$ mag, respectively. This sample includes 37 stars likely to host planets, 32 targets likely to be EBs, and 6 other targets previously labeled as likely planetary false positives. We find nine likely physically bound companion stars within 3'' of three candidate transiting exoplanet host stars and six likely eclipsing binaries (EB). Six of the nine detected companions are new discoveries, one of them associated with a planet candidate (EPIC 206061524). Among the EB candidates, companions were only found near the shortest period ones ($P<3$ days), which is in line with previous results showing high multiplicity near short-period binary stars. This high resolutio...

  7. SPOTS: The Search for Planets Orbiting Two Stars. II. First constraints on the frequency of sub-stellar companions on wide circumbinary orbits

    Science.gov (United States)

    Bonavita, M.; Desidera, S.; Thalmann, C.; Janson, M.; Vigan, A.; Chauvin, G.; Lannier, J.

    2016-09-01

    A large number of direct imaging surveys for exoplanets have been performed in recent years, yielding the first directly imaged planets and providing constraints on the prevalence and distribution of wide planetary systems. However, like most of the radial velocity ones, these generally focus on single stars, hence binaries and higher-order multiples have not been studied to the same level of scrutiny. This motivated the Search for Planets Orbiting Two Stars (SPOTS) survey, which is an ongoing direct imaging study of a large sample of close binaries, started with VLT/NACO and now continuing with VLT/SPHERE. To complement this survey, we have identified the close binary targets in 24 published direct imaging surveys. Here we present our statistical analysis of this combined body of data. We analysed a sample of 117 tight binary systems, using a combined Monte Carlo and Bayesian approach to derive the expected values of the frequency of companions, for different values of the companion's semi-major axis. Our analysis suggest that the frequency of sub-stellar companions in wide orbit is moderately low (≲ 13% with a best value of 6% at 95% confidence level) and not significantly different between single stars and tight binaries. One implication of this result is that the very high frequency of circumbinary planets in wide orbits around post-common envelope binaries, implied by eclipse timing, cannot be uniquely due to planets formed before the common-envelope phase (first generation planets), supporting instead the second generation planet formation or a non-Keplerian origin of the timing variations.

  8. A coordinated optical and X-ray spectroscopic campaign on HD179949: searching for planet-induced chromospheric and coronal activity

    CERN Document Server

    Scandariato, G; Lanza, A F; Pagano, I; Fares, R; Shkolnik, E L; Bohlender, D; Cameron, A C; Dieters, S; Donati, J -F; Fiorenzano, A F Martìnez; Jardine, M; Moutou, C

    2013-01-01

    HD179949 is an F8V star, orbited by a close-in giant planet with a period of ~3 days. Previous studies suggested that the planet enhances the magnetic activity of the parent star, producing a chromospheric hot spot which rotates in phase with the planet orbit. However, this phenomenon is intermittent since it was observed in several but not all seasons. A long-term monitoring of the magnetic activity of HD179949 is required to study the amplitude and time scales of star-planet interactions. In 2009 we performed a simultaneous optical and X-ray spectroscopic campaign to monitor the magnetic activity of HD179949 during ~5 orbital periods and ~2 stellar rotations. We analyzed the CaII H&K lines as a proxy for chromospheric activity, and we studied the X-ray emission in search of flux modulations and to determine basic properties of the coronal plasma. A detailed analysis of the flux in the cores of the CaII H&K lines and a similar study of the X-ray photometry shows evidence of source variability, includ...

  9. The HARPS search for southern extra-solar planets XXXV. Planetary systems and stellar activity of the M dwarfs GJ 3293, GJ 3341, and GJ 3543

    CERN Document Server

    Astudillo-Defru, N; Delfosse, X; Segransan, D; Forveille, T; Bouchy, F; Gillon, M; Lovis, C; Mayor, M; Neves, V; Pepe, F; Perrier, C; Queloz, D; Rojo, P; Santos, N C; Udry, S

    2014-01-01

    Context. Planetary companions of a fixed mass induce larger amplitude reflex motions around lower-mass stars, which helps make M dwarfs excellent targets for extra-solar planet searches. State of the art velocimeters with $\\sim$1m/s stability can detect very low-mass planets out to the habitable zone of these stars. Low-mass, small, planets are abundant around M dwarfs, and most known potentially habitable planets orbit one of these cool stars. Aims. Our M-dwarf radial velocity monitoring with HARPS on the ESO 3.6m telescope at La Silla observatory makes a major contribution to this sample. Methods. We present here dense radial velocity (RV) time series for three M dwarfs observed over $\\sim5$ years: GJ 3293 (0.42M$_\\odot$), GJ 3341 (0.47M$_\\odot$), and GJ 3543 (0.45M$_\\odot$). We extract those RVs through minimum $\\chi^2$ matching of each spectrum against a high S/N ratio stack of all observed spectra for the same star. We then vet potential orbital signals against several stellar activity indicators, to dis...

  10. A comprehensive examination of the Eps Eri system -- Verification of a 4 micron narrow-band high-contrast imaging approach for planet searches

    CERN Document Server

    Janson, Markus; Brandner, Wolfgang; Henning, Thomas; Lenzen, Rainer; Hippler, Stefan

    2008-01-01

    Due to its proximity, youth, and solar-like characteristics with a spectral type of K2V, Eps Eri is one of the most extensively studied systems in an extrasolar planet context. Based on radial velocity, astrometry, and studies of the structure of its circumstellar debris disk, at least two planetary companion candidates to Eps Eri have been inferred in the literature (Eps Eri b, Eps Eri c). Some of these methods also hint at additional companions residing in the system. Here we present a new adaptive optics assisted high-contrast imaging approach that takes advantage of the favourable planet spectral energy distribution at 4 microns, using narrow-band angular differential imaging to provide an improved contrast at small and intermediate separations from the star. We use this method to search for planets at orbits intermediate between Eps Eri b (3.4 AU) and Eps Eri c (40 AU). The method is described in detail, and important issues related to the detectability of planets such as the age of Eps Eri and constrain...

  11. Three New Eclipsing White-dwarf - M-dwarf Binaries Discovered in a Search for Transiting Planets Around M-dwarfs

    CERN Document Server

    Law, Nicholas M; Street, Rachel; Fulton, Benjamin J; Hillenbrand, Lynne A; Shporer, Avi; Lister, Tim; Baranec, Christoph; Bloom, Joshua S; Bui, Khanh; Burse, Mahesh P; Cenko, S Bradley; Das, H K; Davis, Jack T C; Dekany, Richard G; Filippenko, Alexei V; Kasliwal, Mansi M; Kulkarni, S R; Nugent, Peter; Ofek, Eran O; Poznanski, Dovi; Quimby, Robert M; Ramaprakash, A N; Riddle, Reed; Silverman, Jeffrey M; Sivanandam, Suresh; Tendulkar, Shriharsh

    2011-01-01

    We present three new eclipsing white-dwarf / M-dwarf binary systems discovered during a search for transiting planets around M-dwarfs. Unlike most known eclipsing systems of this type, the optical and infrared emission is dominated by the M-dwarf components, and the systems have optical colors and discovery light curves consistent with being Jupiter-radius transiting planets around early M-dwarfs. We detail the PTF/M-dwarf transiting planet survey, part of the Palomar Transient Factory (PTF). We present a Graphics Processing Unit (GPU)-based box-least-squares search for transits that runs approximately 8X faster than similar algorithms implemented on general purpose systems. For the discovered systems, we decompose low-resolution spectra of the systems into white-dwarf and M-dwarf components, and use radial velocity measurements and cooling models to estimate masses and radii for the white dwarfs. The systems are compact, with periods between 0.35 and 0.45 days and semimajor axes of approximately 2 solar radi...

  12. A relook on using the Earth Similarity Index for searching habitable zones around solar and extrasolar planets

    Science.gov (United States)

    Biswas, S.; Shome, A.; Raha, B.; Bhattacharya, A. B.

    2017-01-01

    To study the distribution of Earth-like planets and to locate the habitable zone around extrasolar planets and their known satellites, we have emphasized in this paper the consideration of Earth similarity index (ESI) as a multi parameter quick assessment of Earth-likeness with a value between zero and one. Weight exponent values for four planetary properties have been taken into account to determine the ESI. A plot of surface ESI against the interior ESI exhibits some interesting results which provide further information when confirmed planets are examined. From the analysis of the available catalog and existing theory, none of the solar planets achieves an ESI value greater than 0.8. Though the planet Mercury has a value of 0.6, Mars exhibits a value between 0.6 and 0.8 and the planet Venus shows a value near 0.5. Finally, the locations of the habitable zone around different type of stars are critically examined and discussed.

  13. The HARPS search for southern extra-solar planets XIX. Characterization and dynamics of the GJ876 planetary system

    CERN Document Server

    Correia, A C M; Laskar, J; Bonfils, X; Mayor, M; Bertaux, J -L; Bouchy, F; Delfosse, X; Forveille, T; Lovis, C; Pepe, F; Perrier, C; Queloz, D; Udry, S; 10.1051/0004-6361/200912700

    2010-01-01

    Precise radial-velocity measurements for data acquired with the HARPS spectrograph infer that three planets orbit the M4 dwarf star GJ876. In particular, we confirm the existence of planet "d", which orbits every 1.93785 days. We find that its orbit may have significant eccentricity (e=0.14), and deduce a more accurate estimate of its minimum mass of 6.3 Earth masses. Dynamical modeling of the HARPS measurements combined with literature velocities from the Keck Observatory strongly constrain the orbital inclinations of the "b" and "c" planets. We find that i_b = 48.9 degrees and i_c = 48.1 degrees, which infers the true planet masses of M_b = 2.64 Jupiter masses and M_c = 0.83 Jupiter masses, respectively. Radial velocities alone, in this favorable case, can therefore fully determine the orbital architecture of a multi-planet system, without the input from astrometry or transits. The orbits of the two giant planets are nearly coplanar, and their 2:1 mean motion resonance ensures stability over at least 5 Gyr....

  14. International Astronomical Search Collaboration: An Online Student-Based Discovery Program in Astronomy (Invited)

    Science.gov (United States)

    Pennypacker, C.; Miller, P.

    2009-12-01

    The past 15 years has seen the development of affordable small telescopes, advanced digital cameras, high speed Internet access, and widely-available image analysis software. With these tools it is possible to provide student programs where they make original astronomical discoveries. High school aged students, even younger, have discovered Main Belt asteroids (MBA), near-Earth objects (NEO), comets, supernovae, and Kuiper Belt objects (KBO). Student-based discovery is truly an innovative way to generate enthusiasm for learning science. The International Astronomical Search Collaboration (IASC = “Isaac”) is an online program where high school and college students make original MBA discoveries and important NEO observations. MBA discoveries are reported to the Minor Planet Center (Harvard) and International Astronomical Union. The NEO observations are included as part of the NASA Near-Earth Object Program (JPL). Provided at no cost to participating schools, IASC is centered at Hardin-Simmons University (Abilene, TX). It is a collaboration of the University, Lawrence Hall of Science (University of California, Berkeley), Astronomical Research Institute (ARI; Charleston, IL), Global Hands-On Universe Association (Portugal),and Astrometrica (Austria). Started in Fall 2006, IASC has reached 135 schools in 14 countries. There are 9 campaigns per year, each with 15 schools and lasting 45 days. Students have discovered 150 MBAs and made > 1,000 NEO observations. One notable discovery was 2009 BD81, discovered by two high school teachers and a graduate student at the Bulgarian Academy of Science. This object, about the size of 3 football fields, crosses Earth’s orbit and poses a serious impact risk. Each night with clear skies and no Moon, the ARI Observatory uses its 24" and 32" prime focus telescopes to take images along the ecliptic. Three images are taken of the same field of view (FOV) over a period of 30 minutes. These are bundled together and placed online at

  15. The SOPHIE search for northern extrasolar planets. XI. Three new companions and an orbit update: Giant planets in the habitable zone

    CERN Document Server

    Díaz, R F; Demangeon, O; Hébrard, G; Boisse, I; Arnold, L; Astudillo-Defru, N; Beuzit, J -L; Bonfils, X; Borgniet, S; Bouchy, F; Bourrier, V; Courcol, B; Deleuil, M; Delfosse, X; Ehrenreich, D; Forveille, T; Lagrange, A -M; Mayor, M; Moutou, C; Pepe, F; Queloz, D; Santerne, A; Santos, N C; Sahlmann, J; Ségransan, D; Udry, S; Wilson, P A

    2016-01-01

    We report the discovery of three new substellar companions to solar-type stars, HD191806, HD214823, and HD221585, based on radial velocity measurements obtained at the Haute-Provence Observatory. Data from the SOPHIE spectrograph are combined with observations acquired with its predecessor, ELODIE, to detect and characterise the orbital parameters of three new gaseous giant and brown dwarf candidates. Additionally, we combine SOPHIE data with velocities obtained at the Lick Observatory to improve the parameters of an already known giant planet companion, HD16175 b. Thanks to the use of different instruments, the data sets of all four targets span more than ten years. Zero-point offsets between instruments are dealt with using Bayesian priors to incorporate the information we possess on the SOPHIE/ELODIE offset based on previous studies. The reported companions have orbital periods between three and five years and minimum masses between 1.6 Mjup and 19 Mjup. Additionally, we find that the star HD191806 is expe...

  16. The Unlikely Origins of NASA’s “Search for Origins” Program

    Science.gov (United States)

    Perez, Mario R.; Thronson, Harley A.

    2017-01-01

    NASA’s Origins Program for many years was by far one of the most important scientific initiatives in NASA’s history, linking together priority research campaigns in planetary science, astrophysics, and the biological sciences. It served also as an overarching description to the agency stakeholders of a new generation of major space missions and technology investments. Moreover, the Program, although no longer formally in existence, significantly influences multiple major science priorities for NASA even today. Remarkably, inception of NASA’s Origins Program — The Search for Our Cosmic Roots — two decades ago was initiated by the country’s political leadership, not by the scientific community, the National Academy of Sciences, or by an advisory panel of experts. Instead, it was an initiative by the White House in response to the stunning announcement of ‘evidence’ for life found on a Martian meteorite not long after the discovery of the first extrasolar planet orbiting a sun-like star. A White House memo dated in September 1996, written by John H. Gibbons, Assistant to the President for Science and Technology to Dan Goldin, NASA Administrator at that time, called for a “Space Summit” that would include experts on three broad topics: the universe, planets, and life.The summit was jointly organized by NASA and the National Research Council, and was chaired by Vice-President Al Gore in late October 1996. Three dozen biologists, planetary scientists, astronomers, and cosmologists participated. The outcome was the Origins Program, which has been a prominent part of NASA’s science program ever since, theme which is captured by the simple and profound questions: How Did We Get Here? and Are We Alone?This particular initiative and its genesis demonstrates that science discoveries, followed by political activism and then executive orders can impact and shape for decades the paths to major science priorities, practices, and implementation. In this

  17. Direct dark matter searches and the CDEX research program

    Science.gov (United States)

    Wong, Henry T.; Yue, Qian; Kang, Kejun

    2016-07-01

    We sketch the landscape which gives rise to the missing energy density problem and highlight the direct experimental searches of weakly interacting massive particles (WIMPs) dark matter. An overview of the China Jinping underground laboratory as well as the China dark matter experiment (CDEX) dark matter program based on germanium detectors with sub-keV sensitivities is presented. The achieved results, status as well as the R&D and technology acquisition efforts towards a ton-scale experiment are reported.

  18. The Mt John University Observatory Search For Earth-mass Planets In The Habitable Zone Of Alpha Centauri

    CERN Document Server

    Endl, M; Hearnshaw, J; Barnes, S I; Wittenmyer, R A; Ramm, D; Kilmartin, P; Gunn, F; Brogt, E

    2014-01-01

    The "holy grail" in planet hunting is the detection of an Earth-analog: a planet with similar mass as the Earth and an orbit inside the habitable zone. If we can find such an Earth-analog around one of the stars in the immediate solar neighborhood, we could potentially even study it in such great detail to address the question of its potential habitability. Several groups have focused their planet detection efforts on the nearest stars. Our team is currently performing an intensive observing campaign on the alpha Centauri system using the Hercules spectrograph at the 1-m McLellan telescope at Mt John University Observatory (MJUO) in New Zealand. The goal of our project is to obtain such a large number of radial velocity measurements with sufficiently high temporal sampling to become sensitive to signals of Earth-mass planets in the habitable zones of the two stars in this binary system. Over the past years, we have collected more than 45,000 spectra for both stars combined. These data are currently processed ...

  19. Searching for gas giant planets on Solar System scales - A NACO/APP L'-band survey of A- and F-type Main Sequence stars

    CERN Document Server

    Meshkat, T; Reggiani, M; Quanz, S P; Mamajek, E E; Meyer, M R

    2015-01-01

    We report the results of a direct imaging survey of A- and F-type main sequence stars searching for giant planets. A/F stars are often the targets of surveys, as they are thought to have more massive giant planets relative to solar-type stars. However, most imaging is only sensitive to orbital separations $>$30 AU, where it has been demonstrated that giant planets are rare. In this survey, we take advantage of the high-contrast capabilities of the Apodizing Phase Plate coronagraph on NACO at the Very Large Telescope. Combined with optimized principal component analysis post-processing, we are sensitive to planetary-mass companions (2 to 12 $M_{\\rm Jup}$) at Solar System scales ($\\leq$30 AU). We obtained data on 13 stars in L'-band and detected one new companion as part of this survey: an M$6.0\\pm0.5$ dwarf companion around HD 984. We re-detect low-mass companions around HD 12894 and HD 20385, both reported shortly after the completion of this survey. We use Monte Carlo simulations to determine new constraints...

  20. The HARPS search for southern extra-solar planets. XXXIX. HD175607 b, the most metal-poor G dwarf with an orbiting sub-Neptune

    CERN Document Server

    Mortier, A; Santos, N C; Rajpaul, V; Figueira, P; Boisse, I; Cameron, A Collier; Dumusque, X; Curto, G Lo; Lovis, C; Mayor, M; Melo, C; Pepe, F; Queloz, D; Santerne, A; Ségransan, D; Sousa, S G; Sozzetti, A; Udry, S

    2016-01-01

    Context. The presence of a small-mass planet (M$_p<$0.1\\,M$_{Jup}$) seems, to date, not to depend on metallicity, however, theoretical simulations have shown that stars with subsolar metallicities may be favoured for harbouring smaller planets. A large, dedicated survey of metal-poor stars with the HARPS spectrograph has thus been carried out to search for Neptunes and super-Earths. Aims. In this paper, we present the analysis of \\object{HD175607}, an old G6 star with metallicity [Fe/H] = -0.62. We gathered 119 radial velocity measurements in 110 nights over a time span of more than nine years. Methods. The radial velocities were analysed using Lomb-Scargle periodograms, a genetic algorithm, a Markov chain Monte Carlo analysis, and a Gaussian processes analysis. The spectra were also used to derive stellar properties. Several activity indicators were analysed to study the effect of stellar activity on the radial velocities. Results. We find evidence for the presence of a small Neptune-mass planet (M$_{p}\\s...

  1. ELODIE metallicity-biased search for transiting Hot Jupiters. IV. Intermediate period planets orbiting the stars HD 43691 and HD 132406

    Science.gov (United States)

    da Silva, R.; Udry, S.; Bouchy, F.; Moutou, C.; Mayor, M.; Beuzit, J.-L.; Bonfils, X.; Delfosse, X.; Desort, M.; Forveille, T.; Galland, F.; Hébrard, G.; Lagrange, A.-M.; Loeillet, B.; Lovis, C.; Pepe, F.; Perrier, C.; Pont, F.; Queloz, D.; Santos, N. C.; Ségransan, D.; Sivan, J.-P.; Vidal-Madjar, A.; Zucker, S.

    2007-10-01

    We report here the discovery of two planet candidates as a result of our planet-search programme biased in favour of high-metallicity stars, using the ELODIE spectrograph at the Observatoire de Haute Provence. One candidate has a minimum mass m_2 sin i = 2.5 M_Jup and is orbiting the metal-rich star HD 43691 with period P = 40 days and eccentricity e=0.14. The other planet has a minimum mass m_2 sin{i} = 5.6 M_Jup and orbits the slightly metal-rich star HD 132406 with period P=974 days and eccentricity e = 0.34. Additional observations for both stars were performed using the new SOPHIE spectrograph that replaces the ELODIE instrument, allowing an improved orbital solution for the systems. Based on radial velocities collected with the ELODIE spectrograph mounted on the 193-cm telescope at the Observatoire de Haute Provence, France. Additional observations were made using the new SOPHIE spectrograph (run 06B.PNP.CONS) that replaces ELODIE.

  2. Martian dreaming: The red-hot search for evidence of life on other planets could spur revolutionary new drilling techniques for Planet Earth

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.

    2004-02-01

    The challenge of proving the existence of water, hence the possibility of life, on Mars, the development of lightweight, compact technology to do the necessary drilling and the potential impact that development of that technology may have on drilling technology on Earth, is discussed. One of the most advanced of the projects designed to look deeper into the Martian surface is a joint NASA-Baker Hughes development of a fully automated bottomhole assembly attached by cable that drills fluidless and at low power levels. The device is designed to operate without a drillstring; it acquires a core, hauls it up the cable and goes down again. At least in theory, the cable could be extended more or less indefinitely. The drill is planned to be field-tested in the Canadian High Arctic. Automation of the equipment that will be able to deal with the wide variety of situations that challenge even the best human operators, will be the most likely legacy of the program that could have the potential to make useful contributions to the exploration industry. Various other projects, such as laser drilling, and drilling with Kevlar coiled tubing containing geophysical sensors embedded in the drill collars, are underway at the Colorado School of Mines. Honeybee Robotics has developed a prototype one-metre drill, that is capable of taking core samples and transfer them to a spectrometer. They are also developing the unique Inchworm deep drilling system that will be capable to burrow several kilometres below the surface. Among these experimental projects the Inchworm system in particular is seen as having the greatest potential for application in the oil and gas industry. An all-Canadian mission to Mars scheduled for 2011 that could leverage Canadian mining industry drilling technology to drill for rock samples is also reported.

  3. Planet X - Fact or fiction?

    Science.gov (United States)

    Anderson, John

    1988-01-01

    The search for a possible tenth planet in our solar system is examined. The history of the discoveries of Uranus, Neptune, and Pluto are reviewed. Searches of the sky with telescopes and theoretical studies of the gravitational influences on the orbits of known objects in the solar system are discussed. Information obtained during the Pioneer 10 and 11 missions which could suggest the presence of an undiscovered planet and computer simulations of the possible orbit of a tenth planet are presented.

  4. A Rapid Grid Search Method for Solving Dynamic Programming Problems in Economics

    OpenAIRE

    Hui He; Hao Zhang

    2013-01-01

    We introduce a rapid grid search method in solving dynamic programming problems in economics. Compared to mainstream grid search methods, by using local information of the Bellman equation, this method can significantly increase the efficiency in solving dynamic programming problems by reducing the grid points searched in the control space.

  5. A Note on a Rapid Grid Search Method for Solving Dynamic Programming Problems in Economics

    OpenAIRE

    Hui He; Hao Zhang

    2010-01-01

    We introduce a rapid grid search method in solving the dynamic programming problems in economics. Compared to mainstream grid search methods, by using local information of the Bellman equation, this method can significantly increase the efficiency in solving dynamic programming problems by reducing the grid points searched in the control space.

  6. Spitzer Microlensing Program as a Probe for Globular Cluster Planets. Analysis of OGLE-2015-BLG-0448

    CERN Document Server

    Poleski, Radosław; Christie, Grant W; Udalski, Andrzej; Gould, Andrew; Bachelet, Etienne; Skottfelt, Jesper; Novati, Sebastiano Calchi; Szymański, M K; Soszyński, I; Pietrzyński, G; Wyrzykowski, Ł; Ulaczyk, K; Pietrukowicz, P; Kozłowski, Szymon; Skowron, J; Mróz, P; Pawlak, M; Beichman, C; Bryden, G; Carey, S; Fausnaugh, M; Gaudi, B S; Henderson, C B; Pogge, R W; Shvartzvald, Y; Wibking, B; Yee, J C; Beatty, T G; Eastman, J D; Drummond, J; Friedmann, M; Henderson, M; Johnson, J A; Kaspi, S; Maoz, D; McCormick, J; McCrady, N; Natusch, T; Ngan, H; Porritt, I; Relles, H M; Sliski, D H; Tan, T -G; Wittenmyer, R A; Wright, J T; Street, R A; Tsapras, Y; Bramich, D M; Horne, K; Snodgrass, C; Steele, I A; Menzies, J; Jaimes, R Figuera; Wambsganss, J; Schmidt, R; Cassan, A; Ranc, C; Mao, S; Bozza, V; Dominik, M; Hundertmark, M P G; Jørgensen, U G; Andersen, M I; Burgdorf, M J; Ciceri, S; D'Ago, G; Evans, D F; Gu, S -H; Hinse, T C; Kains, N; Kerins, E; Korhonen, H; Kuffmeier, M; Mancini, L; Popovas, A; Rabus, M; Rahvar, S; Rasmussen, R T; Southworth, G Scarpetta J; Surdej, J; Unda-Sanzana, E; Verma, P; von Essen, C; Wang, Y -B; Wertz, O

    2015-01-01

    The microlensing event OGLE-2015-BLG-0448 was observed by Spitzer and lay within the tidal radius of the globular cluster NGC 6558. The event had moderate magnification and was intensively observed, hence it had the potential to probe the distribution of planets in globular clusters. We measure the proper motion of NGC 6558 ($\\mu_{\\rm cl}$(N,E) = (+0.36+-0.10, +1.42+-0.10) mas/yr) as well as the source and show that the lens is not a cluster member. Even though this particular event does not probe the distribution of planets in globular clusters, other potential cluster lens events can be verified using our methodology. Additionally, we find that microlens parallax measured using OGLE photometry is consistent with the value found based on the light curve displacement between Earth and Spitzer.

  7. Double-blind test program for astrometric planet detection with Gaia

    CERN Document Server

    Casertano, S; Sozzetti, A; Spagna, A; Jancart, S; Morbidelli, R; Pannunzio, R; Pourbaix, D; Queloz, D

    2008-01-01

    We use detailed simulations of the Gaia observations of synthetic planetary systems and develop and utilize independent software codes in double-blind mode to analyze the data, including statistical tools for planet detection and different algorithms for single and multiple Keplerian orbit fitting that use no a priori knowledge of the true orbital parameters of the systems. 1) Planets with astrometric signatures $\\alpha\\simeq 3$ times the single-measurement error $\\sigma_\\psi$ and period $P\\leq 5$ yr can be detected reliably, with a very small number of false positives. 2) At twice the detection limit, uncertainties in orbital parameters and masses are typically $15%-20%$. 3) Over 70% of two-planet systems with well-separated periods in the range $0.2\\leq P\\leq 9$ yr, $2\\leq\\alpha/\\sigma_\\psi\\leq 50$, and eccentricity $e\\leq 0.6$ are correctly identified. 4) Favorable orbital configurations have orbital elements measured to better than 10% accuracy $> 90%$ of the time, and the value of the mutual inclination ...

  8. ARTEMiS (Automated Robotic Terrestrial Exoplanet Microlensing Search) - A possible expert-system based cooperative effort to hunt for planets of Earth mass and below

    CERN Document Server

    Dominik, M; Allan, A; Rattenbury, N J; Tsapras, Y; Snodgrass, C; Bode, M F; Burgdorf, M J; Fraser, S N; Kerins, E; Mottram, C J; Steele, I A; Street, R A; Wheatley, P J; Wyrzykowski, L

    2008-01-01

    (abridged) The technique of gravitational microlensing is currently unique in its ability to provide a sample of terrestrial exoplanets around both Galactic disk and bulge stars, allowing to measure their abundance and determine their distribution with respect to mass and orbital separation. In order to achieve these goals in reasonable time, a well-coordinated effort involving a network of either 2m or 4 x 1m telescopes at each site is required. It could lead to the first detection of an Earth-mass planet outside the Solar system, and even planets less massive than Earth could be discovered. From April 2008, ARTEMiS (Automated Robotic Terrestrial Exoplanet Microlensing Search) is planned to provide a platform for a three-step strategy of survey, follow-up, and anomaly monitoring. As an expert system embedded in eSTAR (e-Science Telescopes for Astronomical Research), ARTEMiS will give advice on the optimal targets to be observed at any given time, and will also alert on deviations from ordinary microlensing l...

  9. SPOTS: The Search for Planets Orbiting Two Stars: II. First constraints on the frequency of sub-stellar companions on wide circumbinary orbits

    CERN Document Server

    Bonavita, Mariangela; Thalmann, Christian; Janson, Markus; Vigan, Arthur; Chauvin, Gael; Lannier, Justine

    2016-01-01

    A large number of direct imaging surveys for exoplanets have been performed in recent years, yielding the first directly imaged planets and providing constraints on the prevalence and distribution of wide planetary systems. However, like most of the radial velocity ones, these surveys generally focus on single stars, hence binaries and higher-order multiples have not been studied to the same level of scrutiny. This motivated the SPOTS (Search for Planets Orbiting Two Stars) survey, which is an ongoing direct imaging study of a large sample of close binaries, started with VLT/NACO and now continuing with VLT/SPHERE. To complement this survey, we have identified the close binary targets in 24 published direct imaging surveys. Here we present our statistical analysis of this combined body of data. We analysed a sample of 117 tight binary systems, using a combined Monte Carlo and Bayesian approach to derive the expected values of the frequency of companions, for different values of the companion's semi-major axis...

  10. Discovery of abundant cellulose microfibers encased in 250 Ma Permian halite: a macromolecular target in the search for life on other planets.

    Science.gov (United States)

    Griffith, Jack D; Willcox, Smaranda; Powers, Dennis W; Nelson, Roger; Baxter, Bonnie K

    2008-04-01

    In this study, we utilized transmission electron microscopy to examine the contents of fluid inclusions in halite (NaCl) and solid halite crystals collected 650 m below the surface from the Late Permian Salado Formation in southeastern New Mexico (USA). The halite has been isolated from contaminating groundwater since deposition approximately 250 Ma ago. We show that abundant cellulose microfibers are present in the halite and appear remarkably intact. The cellulose is in the form of 5 nm microfibers as well as composite ropes and mats, and was identified by resistance to 0.5 N NaOH treatment and susceptibility to cellulase enzyme treatment. These cellulose microfibers represent the oldest native biological macromolecules to have been directly isolated, examined biochemically, and visualized (without growth or replication) to date. This discovery points to cellulose as an ideal macromolecular target in the search for life on other planets in our Solar System.

  11. International Asteroid Search Campaign: An Educational Outreach Program in Astronomy for High Schools and Colleges

    Science.gov (United States)

    Miller, J. P.; Juliano, D.; Davis, J. W.; Holmes, R. E.; Devore, H.; Raab, H.; Pennypacker, C. R.; White, G. L.; Gould, A.

    2008-03-01

    The International Asteroid Search Campaign is an Internet-based program for high schools and colleges. Schools receive images, analyzed by students searching for asteroids and NEOs. Students have 71 asteroid discoveries and 1376 NEO observations.

  12. March of the Planets

    Science.gov (United States)

    Thompson, Bruce

    2007-01-01

    The motion of the planets in their orbits can be demonstrated to students by using planetarium software programs. These allow time to be sped up so that the relative motions are readily observed. However, it is also valuable to have the students understand the real speed of the planets in their orbits. This paper describes an exercise that gives…

  13. A Search for H-alpha Absorption in the Exosphere of the Transiting Extrasolar Planet HD 209458b

    CERN Document Server

    Winn, J N; Turner, E L; Narita, N; Frye, B L; Aoki, W; Sato, B; Yamada, T; Winn, Joshua N.; Suto, Yasushi; Turner, Edwin L.; Narita, Norio; Frye, Brenda L.; Aoki, Wako; Sato, Bunei; Yamada, Toru

    2004-01-01

    There is evidence that the transiting planet HD 209458b has a large exosphere of neutral hydrogen, based on a 15% decrement in Lyman-alpha flux that was observed by Vidal-Madjar et al. during transits. Here we report upper limits on Balmer-alpha (H-alpha) absorption by the exosphere. The results are based on optical spectra of the parent star obtained with the Subaru High Dispersion Spectrograph. Comparison of the spectra taken inside and outside of transit reveals no exospheric H-alpha signal greater than 0.1% within a 5.1AA band (chosen to have the same Dlambda/lambda as the 15% Ly-alpha absorption). The corresponding limit on the column density of n=2 neutral hydrogen is N_2 <~ 10^9 cm^{-2}. This limit constrains proposed models involving a hot (~10^4 K) and hydrodynamically escaping exosphere.

  14. The Rocky Planet Survey

    Science.gov (United States)

    Fischer, Debra

    In direct support of the NASA Origins program, we propose the Rocky Planet Survey, a high cadence exoplanet search of sixty late G and K dwarf stars using the CHIRON spectrometer, which we built and commissioned at CTIO. CHIRON operates in two high- resolution modes (R=90,000 and R=120,000) and has a demonstrated precision of better than 1 m s-1. We are contributing 200 nights of telescope time for the next three years, for the excellent phase coverage needed to carry out this work. We have developed simulation software to optimize scheduling of observations to suppress aliases and quickly extract dynamical signals. Our science objectives are to (1) provide a statistical assessment of planet occurrence as a function of decreasing mass in the range of parameter space 3 objectives, we intend to push the frontiers of extreme precision Doppler measurements to keep the U.S. competitive with the next generation of European Doppler spectroscopy (ESPRESSO on the VLT). Our team has significant expertise in optical design, fiber coupling, raw extraction, barycentric velocity corrections, and Doppler analysis. The proposed work includes a new optimal extraction algorithm, with the optical designers and software engineers working together on the 2-D PSF description needed for a proper row-by-row extraction and calibration. We will also develop and test upgrades to the barycentric correction code and improvements in the Doppler code that take advantage of stability in the dispersion solution, afforded by a new vacuum-enclosed grating upgrade (scheduled for November 2011). We will test use of emission wavelength calibrations to extend the iodine (absorption) wavelength calibration that we currently use to prepare for eventual use of stabilized etalons or laser frequency combs. Radial velocity measurements play a fundamental role, both in the detection of exoplanets and in support of NASA missions. This program will train postdoctoral fellows, grad students and undergrads, while

  15. Automated Literature Searches for Longitudinal Tracking of Cancer Research Training Program Graduates.

    Science.gov (United States)

    Padilla, Luz A; Desmond, Renee A; Brooks, C Michael; Waterbor, John W

    2016-10-12

    A key outcome measure of cancer research training programs is the number of cancer-related peer-reviewed publications after training. Because program graduates do not routinely report their publications, staff must periodically conduct electronic literature searches on each graduate. The purpose of this study is to compare findings of an innovative computer-based automated search program versus repeated manual literature searches to identify post-training peer-reviewed publications. In late 2014, manual searches for publications by former R25 students identified 232 cancer-related articles published by 112 of 543 program graduates. In 2016, a research assistant was instructed in performing Scopus literature searches for comparison with individual PubMed searches on our 543 program graduates. Through 2014, Scopus found 304 cancer publications, 220 of that had been retrieved manually plus an additional 84 papers. However, Scopus missed 12 publications found manually. Together, both methods found 316 publications. The automated method found 96.2 % of the 316 publications while individual searches found only 73.4 %. An automated search method such as using the Scopus database is a key tool for conducting comprehensive literature searches, but it must be supplemented with periodic manual searches to find the initial publications of program graduates. A time-saving feature of Scopus is the periodic automatic alerts of new publications. Although a training period is needed and initial costs can be high, an automated search method is worthwhile due to its high sensitivity and efficiency in the long term.

  16. Exploring Disks Around Planets

    Science.gov (United States)

    Kohler, Susanna

    2017-07-01

    masses on the properties of the disks. Szulgyi specifically examines a range of planetary temperatures between 10,000 K and 1,000 K for the 1 MJ planet. Since the planet cools as it radiates away its formation heat, the different temperatures represent an evolutionary sequence over time.Predicted CharacteristicsSzulgyis work produced a number of intriguing observations, including the following:For the 1 MJ planet, a spherical circumplanetary envelope forms at high temperatures, flattening into a disk as the planet cools. Higher-mass planets form disks even at high temperatures.The disk has a steep temperature profile from inside to outside, and the whole disk is too hot for water to remain frozen. This suggests that satellites couldnt form in the disk earlier than 1 Myr after the planet birth. The outskirts of the disk cool first as the planet cools, indicating that satellites may eventually form in these outer parts and then migrate inward.The planets open gaps in the circumstellar disk as they orbit. As a planet radiates away its formation heat, the gap it opens becomes deeper and wider (though this is a small effect). For high-mass planets (5 MJ), the gap eccentricity increases, which creates a hostile environment for satellite formation.Szulgyi discusses a number of features of these disks that we can plan to search for in the future with our increasing telescope power including signatures in direct imaging and observations of their kinematics. The results from these simulations will help us both to detect these circumplanetary disks and to understand our observations when we do. These future observations will then allow us to learn about late-stage giant-planet formation as well as the formation of their satellites.CitationJ. Szulgyi 2017 ApJ 842 103. doi:10.3847/1538-4357/aa7515

  17. M dwarf search for pulsations within Kepler GO program

    CERN Document Server

    Rodríguez-López, C; MacDonald, J; Amado, P J; Carosso, A

    2014-01-01

    We present the analysis of four M dwarf stars -plus one M giant that seeped past our selection criteria- observed in Cycle 3 of Kepler Guest Observer program (GO3) in a search for intrinsic pulsations. Stellar oscillations in M dwarfs were theoretically predicted by Rodr\\'iguez-L\\'opez et al. (2012) to be in the range ~20-40 min and ~4-8 h, depending on the age and the excitation mechanism. We requested Kepler short cadence observations to have an adequate sampling of the oscillations. The targets were chosen on the basis of detectable rotation in the initial Kepler results, biasing towards youth.The analysis reveals no oscillations attributable to pulsations at a detection limit of several parts per million, showing that either the driving mechanisms are not efficient in developing the oscillations to observable amplitudes, or that if pulsations are driven, the amplitudes are very low. The size of the sample, and the possibility that the instability strip is not pure, allowing the coexistence of pulsators an...

  18. Inferring Planet Occurrence Rates With a Q1-Q17 Kepler Planet Candidate Catalog Produced by a Machine Learning Classifier

    Science.gov (United States)

    Catanzarite, Joseph; Jenkins, Jon Michael; McCauliff, Sean D.; Burke, Christopher; Bryson, Steve; Batalha, Natalie; Coughlin, Jeffrey; Rowe, Jason; mullally, fergal; thompson, susan; Seader, Shawn; Twicken, Joseph; Li, Jie; morris, robert; smith, jeffrey; haas, michael; christiansen, jessie; Clarke, Bruce

    2015-08-01

    NASA’s Kepler Space Telescope monitored the photometric variations of over 170,000 stars, at half-hour cadence, over its four-year prime mission. The Kepler pipeline calibrates the pixels of the target apertures for each star, produces light curves with simple aperture photometry, corrects for systematic error, and detects threshold-crossing events (TCEs) that may be due to transiting planets. The pipeline estimates planet parameters for all TCEs and computes diagnostics used by the Threshold Crossing Event Review Team (TCERT) to produce a catalog of objects that are deemed either likely transiting planet candidates or false positives.We created a training set from the Q1-Q12 and Q1-Q16 TCERT catalogs and an ensemble of synthetic transiting planets that were injected at the pixel level into all 17 quarters of data, and used it to train a random forest classifier. The classifier uniformly and consistently applies diagnostics developed by the Transiting Planet Search and Data Validation pipeline components and by TCERT to produce a robust catalog of planet candidates.The characteristics of the planet candidates detected by Kepler (planet radius and period) do not reflect the intrinsic planet population. Detection efficiency is a function of SNR, so the set of detected planet candidates is incomplete. Transit detection preferentially finds close-in planets with nearly edge-on orbits and misses planets whose orbital geometry precludes transits. Reliability of the planet candidates must also be considered, as they may be false positives. Errors in detected planet radius and in assumed star properties can also bias inference of intrinsic planet population characteristics.In this work we infer the intrinsic planet population, starting with the catalog of detected planet candidates produced by our random forest classifier, and accounting for detection biases and reliabilities as well as for radius errors in the detected population.Kepler was selected as the 10th mission

  19. Planet Ocean

    Science.gov (United States)

    Afonso, Isabel

    2014-05-01

    A more adequate name for Planet Earth could be Planet Ocean, seeing that ocean water covers more than seventy percent of the planet's surface and plays a fundamental role in the survival of almost all living species. Actually, oceans are aqueous solutions of extraordinary importance due to its direct implications in the current living conditions of our planet and its potential role on the continuity of life as well, as long as we know how to respect the limits of its immense but finite capacities. We may therefore state that natural aqueous solutions are excellent contexts for the approach and further understanding of many important chemical concepts, whether they be of chemical equilibrium, acid-base reactions, solubility and oxidation-reduction reactions. The topic of the 2014 edition of GIFT ('Our Changing Planet') will explore some of the recent complex changes of our environment, subjects that have been lately included in Chemistry teaching programs. This is particularly relevant on high school programs, with themes such as 'Earth Atmosphere: radiation, matter and structure', 'From Atmosphere to the Ocean: solutions on Earth and to Earth', 'Spring Waters and Public Water Supply: Water acidity and alkalinity'. These are the subjects that I want to develop on my school project with my pupils. Geographically, our school is located near the sea in a region where a stream flows into the sea. Besides that, our school water comes from a borehole which shows that the quality of the water we use is of significant importance. This project will establish and implement several procedures that, supported by physical and chemical analysis, will monitor the quality of water - not only the water used in our school, but also the surrounding waters (stream and beach water). The samples will be collected in the borehole of the school, in the stream near the school and in the beach of Carcavelos. Several physical-chemical characteristics related to the quality of the water will

  20. CoRoT’s first seven planets: An overview*

    Directory of Open Access Journals (Sweden)

    Barge P.

    2011-07-01

    Full Text Available The up to 150 day uninterrupted high-precision photometry of about 100000 stars – provided so far by the exoplanet channel of the CoRoT space telescope – gave a new perspective on the planet population of our galactic neighbourhood. The seven planets with very accurate parameters widen the range of known planet properties in almost any respect. Giant planets have been detected at low metallicity, rapidly rotating and active, spotted stars. CoRoT-3 populated the brown dwarf desert and closed the gap of measured physical properties between standard giant planets and very low mass stars. CoRoT extended the known range of planet masses down-to 5 Earth masses and up to 21 Jupiter masses, the radii to less than 2 Earth radii and up to the most inflated hot Jupiter found so far, and the periods of planets discovered by transits to 9 days. Two CoRoT planets have host stars with the lowest content of heavy elements known to show a transit hinting towards a different planet-host-star-metallicity relation then the one found by radial-velocity search programs. Finally the properties of the CoRoT-7b prove that terrestrial planets with a density close to Earth exist outside the Solar System. The detection of the secondary transit of CoRoT-1 at the 10−5-level and the very clear detection of the 1.7 Earth radii of CoRoT-7b at 3.5 10−4 relative flux are promising evidence of CoRoT being able to detect even smaller, Earth sized planets.

  1. The CRIRES Search for Planets Around the Lowest-Mass Stars. I. High-Precision Near-Infrared Radial Velocities with an Ammonia Gas Cell

    CERN Document Server

    Bean, Jacob L; Hartman, Henrik; Nilsson, Hampus; Wiedemann, Guenter; Reiners, Ansgar; Dreizler, Stefan; Henry, Todd J

    2009-01-01

    Radial velocities measured from near-infrared spectra are a potentially powerful tool to search for planets around cool stars and sub-stellar objects. However, no technique currently exists that yields near-infrared radial velocity precision comparable to that which is routinely obtained in the visible. We describe a method for measuring high-precision relative radial velocities of cool stars from K-band spectra. The method makes use of a glass cell filled with ammonia gas to calibrate the spectrograph response similar to the iodine cell technique that has been used so successfully in the visible. Stellar spectra are obtained through the ammonia cell and modeled as the product of a Doppler-shifted template spectrum of the object and a spectrum of the cell, convolved with a variable instrumental profile model. A complicating factor is that a significant number of telluric absorption lines are present in the spectral regions containing useful stellar and ammonia lines. The telluric lines are modeled simultaneou...

  2. MARVELS-1: A face-on double-lined binary star masquerading as a resonant planetary system; and consideration of rare false positives in radial velocity planet searches

    CERN Document Server

    Wright, Jason T; Mahadevan, Suvrath; Wang, Sharon X; Ford, Eric B; Payne, Matt; Lee, Brian L; Wang, Ji; Crepp, Justin R; Gaudi, B Scott; Eastman, Jason; Pepper, Joshua; Ge, Jian; Fleming, Scott W; Ghezzi, Luan; Gonzalez-Hernandez, Jonay I; Cargile, Phillip; Stassun, Keivan G; Wisniewski, John; Dutra-Ferreira, Leticia; de Mello, Gustavo F Porto; Maia, Marcio A G; da Costa, Luiz Nicolaci; Ogando, Ricardo L C; Santiago, Basilio X; Schneider, Donald P; Hearty, Fred R

    2013-01-01

    We have analyzed new and previously published radial velocity observations of MARVELS-1, known to have an ostensibly substellar companion in a ~6- day orbit. We find significant (~100 m/s) residuals to the best-fit model for the companion, and these residuals are naively consistent with an interior giant planet with a P = 1.965d in a nearly perfect 3:1 period commensuribility (|Pb/Pc - 3| < 10^{-4}). We have performed several tests for the reality of such a companion, including a dynamical analysis, a search for photometric variability, and a hunt for contaminating stellar spectra. We find many reasons to be critical of a planetary interpretation, including the fact that most of the three-body dynamical solutions are unstable. We find no evidence for transits, and no evidence of stellar photometric variability. We have discovered two apparent companions to MARVELS-1 with adaptive optics imaging at Keck; both are M dwarfs, one is likely bound, and the other is likely a foreground object. We explore false-al...

  3. Characterizing small planets transiting small stars with SPIRou

    CERN Document Server

    Santerne, A; Doyon, R; Delfosse, X; Artigau, É; Boisse, I; Bonfils, X; Bouchy, F; Hébrard, G; Moutou, C; Udry, S

    2013-01-01

    SPIRou, a near infrared spectropolarimeter, is a project of new instrument to be mounted at the Canada France Hawaii Telescope in 2017. One of the main objectives of SPIRou is to reach a radial velocity accuracy better than 1 m/s in the YJHK bands. SPIRou will make a cornerstone into the characterization of Earth-like planets, where the exoplanet statistics is very low. This is even more true for planets transiting M dwarfs, since only 3 low-mass planets have been secured so far to transit such stars. We present here all the synergies that SPIRou will provide to and benefit from photometric transit-search programs from the ground or from space (Kepler, CHEOPS, TESS, PLATO 2.0). We also discuss the impact of SPIRou for the characterization of planets orbiting actives stars.

  4. Extrasolar planets.

    Science.gov (United States)

    Lissauer, J J; Marcy, G W; Ida, S

    2000-11-07

    The first known extrasolar planet in orbit around a Sun-like star was discovered in 1995. This object, as well as over two dozen subsequently detected extrasolar planets, were all identified by observing periodic variations of the Doppler shift of light emitted by the stars to which they are bound. All of these extrasolar planets are more massive than Saturn is, and most are more massive than Jupiter. All orbit closer to their stars than do the giant planets in our Solar System, and most of those that do not orbit closer to their star than Mercury is to the Sun travel on highly elliptical paths. Prevailing theories of star and planet formation, which are based on observations of the Solar System and of young stars and their environments, predict that planets should form in orbit about most single stars. However, these models require some modifications to explain the properties of the observed extrasolar planetary systems.

  5. The Dependence of Signal-To-Noise Ratio (S/N) Between Star Brightness and Background on the Filter Used in Images Taken by the Vulcan Photometric Planet Search Camera

    Science.gov (United States)

    Mena-Werth, Jose

    1998-01-01

    The Vulcan Photometric Planet Search is the ground-based counterpart of Kepler Mission Proposal. The Kepler Proposal calls for the launch of telescope to look intently at a small patch of sky for four year. The mission is designed to look for extra-solar planets that transit sun-like stars. The Kepler Mission should be able to detect Earth-size planets. This goal requires an instrument and software capable of detecting photometric changes of several parts per hundred thousand in the flux of a star. The goal also requires the continuous monitoring of about a hundred thousand stars. The Kepler Mission is a NASA Discovery Class proposal similar in cost to the Lunar Prospector. The Vulcan Search is also a NASA project but based at Lick Observatory. A small wide-field telescope monitors various star fields successively during the year. Dozens of images, each containing tens of thousands of stars, are taken any night that weather permits. The images are then monitored for photometric changes of the order of one part in a thousand. These changes would reveal the transit of an inner-orbit Jupiter-size planet similar to those discovered recently in spectroscopic searches. In order to achieve a one part in one thousand photometric precision even the choice of a filter used in taking an exposure can be critical. The ultimate purpose of an filter is to increase the signal-to-noise ratio (S/N) of one's observation. Ideally, filters reduce the sky glow cause by street lights and, thereby, make the star images more distinct. The higher the S/N, the higher is the chance to observe a transit signal that indicates the presence of a new planet. It is, therefore, important to select the filter that maximizes the S/N.

  6. Our changing planet: The FY 1994 US Global Change Research Program

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    The approach of the US Global Change Research Program recognizes the profound economic and social implications of responding to global envirorunental changes and advances US leadership on this issue. The report outlines a careful blend of ground- and space-based efforts in research, data gathering, and modeling activities, as well as economic research, with both near- and long-term scientific and public policy benefits. In FY 1994, the Program will add an explicit focus on assessment, seeking to improve our understanding of the state of scientific knowledge and the implications of that knowledge for national and international policymaking activities.

  7. Installation Restoration Program. Phase 1: Records Search, Williams AFB, Arizona

    Science.gov (United States)

    1984-02-01

    Initial Assess- ment/Records Search; Phase II, Confirmation and Quantification ; Phase III, Technology Base Development; and Phase IV, Operations /Remedial...Search Phase II - Confirmation and Quantification Phase III - Technology Base Development Phase IV - Operations/Remedial Actions Engineering-Science (ES... Alkaloid Avi trol Gopher Getter Pivalyl • New chemicals in use. Will be included in 1984 Pest Management Plan. Note: All chemicals applied by contractors

  8. Extrasolar Planet Inferometric Survey (EPIcS)

    Science.gov (United States)

    Shao, Michael; Baliunas, Sallie; Boden, Andrew; Kulkarni, Shrinivas; Lin, Douglas N. C.; Loredo, Tom; Queloz, Didier; Shaklan, Stuart; Tremaine, Scott; Wolszczan, Alexander

    2004-01-01

    The discovery of the nature of the solar system was a crowning achievement of Renaissance science. The quest to evaluate the properties of extrasolar planetary systems is central to both the intellectual understanding of our origins and the cultural understanding of humanity's place in the Universe; thus it is appropriate that the goals and objectives of NASA's breakthrough Origins program emphasize the study of planetary systems, with a focus on the search for habitable planets. We propose an ambitious research program that will use SIM - the first major mission of the Origins program - to explore planetary systems in our Galactic neighborhood. Our program is a novel two-tiered SIM survey of nearby stars that exploits the capabilities of SIM to achieve two scientific objectives: (i) to identify Earth-like planets in habitable regions around nearby Sunlike stars: and (ii) to explore the nature and evolution of planetary systems in their full variety. The first of these objectives was recently recommended by the Astronomy and Astrophysics Survey Committee (the McKee-Taylor Committee) as a prerequisite for the development of the Terrestrial Planet Finder mission later in the decade. Our program combines this two-part survey with preparatory and contemporaneous research designed to maximize the scientific return from the limited and thus precious observing resources of SIM.

  9. An Integer Programming-based Local Search for Large-scale Maximal Covering Problems

    Directory of Open Access Journals (Sweden)

    Junha Hwang

    2011-02-01

    Full Text Available Maximal covering problem (MCP is classified as a linear integer optimization problem which can be effectively solved by integer programming technique. However, as the problem size grows, integerprogramming requires excessive time to get an optimal solution. This paper suggests a method for applying integer programming-based local search (IPbLS to solve large-scale maximal covering problems. IPbLS, which is a hybrid technique combining integer programming and local search, is a kind of local search using integer programming for neighbor generation. IPbLS itself is very effective for MCP. In addition, we improve the performance of IPbLS for MCP through problem reduction based on the current solution. Experimental results show that the proposed method considerably outperforms any other local search techniques and integer programming.

  10. The Solar Twin Planet Search. III. The [Y/Mg] clock: estimating stellar ages of solar-type stars

    Science.gov (United States)

    Tucci Maia, M.; Ramírez, I.; Meléndez, J.; Bedell, M.; Bean, J. L.; Asplund, M.

    2016-05-01

    Context. Solar twins are stars with similar stellar (surface) parameters to the Sun that can have a wide range of ages. This provides an opportunity to analyze the variation of their chemical abundances with age. Nissen (2015, A&A, 579, A52) recently suggested that the abundances of the s-process element Y and the α-element Mg could be used to estimate stellar ages. Aims: This paper aims to determine with high precision the Y, Mg, and Fe abundances for a sample of 88 solar twins that span a broad age range (0.3-10.0 Gyr) and investigate their use for estimating ages. Methods: We obtained high-quality Magellan Inamori Kyocera Echelle (MIKE) spectra and determined Y and Mg abundances using equivalent widths and a line-by-line differential method within a 1D LTE framework. Stellar parameters and iron abundances were measured in Paper I of this series for all stars, but a few (three) required a small revision. Results: The [Y/Mg] ratio shows a strong correlation with age. It has a slope of -0.041 ± 0.001 dex/Gyr and a significance of 41σ. This is in excellent agreement with the relation first proposed by Nissen (2015). We found some outliers that turned out to be binaries where mass transfer may have enhanced the yttrium abundance. Given a precise measurement of [Y/Mg] with typical error of 0.02 dex in solar twins, our formula can be used to determine a stellar age with ~0.8 Gyr precision in the 0 to 10 Gyr range. Based on observations obtained at the Clay Magellan Telescopes at Las Campanas Observatory, Chile and at the 3.6 m Telescope at the La Silla ESO Observatory, Chile (program ID 188.C-0265).

  11. A sequential quadratically constrained quadratic programming method with an augmented Lagrangian line search function

    Science.gov (United States)

    Tang, Chun-Ming; Jian, Jin-Bao

    2008-10-01

    Based on an augmented Lagrangian line search function, a sequential quadratically constrained quadratic programming method is proposed for solving nonlinearly constrained optimization problems. Compared to quadratic programming solved in the traditional SQP methods, a convex quadratically constrained quadratic programming is solved here to obtain a search direction, and the Maratos effect does not occur without any other corrections. The "active set" strategy used in this subproblem can avoid recalculating the unnecessary gradients and (approximate) Hessian matrices of the constraints. Under certain assumptions, the proposed method is proved to be globally, superlinearly, and quadratically convergent. As an extension, general problems with inequality and equality constraints as well as nonmonotone line search are also considered.

  12. Our Changing Planet: The U.S. Climate Change Science Program for Fiscal Year 2008

    Science.gov (United States)

    2007-10-01

    unclassified b. ABSTRACT unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 William J. Brennan Department...influence, psychological factors, and cognitive decisional factors in adolescence . Other studies are looking at the role of UV light exposure in the...Mississippi and Delaware River basins, the latter in collaboration with the USDA Forest Service Forest Inventory and Analysis Program. • Carbon

  13. Promoting Knowledge to Action through the Study of Environmental Arctic Change (SEARCH) Program

    Science.gov (United States)

    Myers, B.; Wiggins, H. V.

    2016-12-01

    The Study of Environmental Arctic Change (SEARCH) is a multi-institutional collaborative U.S. program that advances scientific knowledge to inform societal responses to Arctic change. Currently, SEARCH focuses on how diminishing Arctic sea ice, thawing permafrost, and shrinking land ice impact both Arctic and global systems. Emphasizing "knowledge to action", SEARCH promotes collaborative research, synthesizes research findings, and broadly communicates the resulting knowledge to Arctic researchers, stakeholders, policy-makers, and the public. This poster presentation will highlight recent program products and findings; best practices and challenges for managing a distributed, interdisciplinary program; and plans for cross-disciplinary working groups focused on Arctic coastal erosion, synthesis of methane budgets, and development of Arctic scenarios. A specific focus will include how members of the broader research community can participate in SEARCH activities. http://www.arcus.org/search

  14. Magic Planet

    DEFF Research Database (Denmark)

    Jacobsen, Aase Roland

    2009-01-01

    Med den digitale globe som omdrejningspunkt bestemmer publikum, hvilken planet, der er i fokus. Vores solsystem udforskes interaktivt. Udgivelsesdato: november......Med den digitale globe som omdrejningspunkt bestemmer publikum, hvilken planet, der er i fokus. Vores solsystem udforskes interaktivt. Udgivelsesdato: november...

  15. MARVELS-1: A FACE-ON DOUBLE-LINED BINARY STAR MASQUERADING AS A RESONANT PLANETARY SYSTEM AND CONSIDERATION OF RARE FALSE POSITIVES IN RADIAL VELOCITY PLANET SEARCHES

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Jason T.; Roy, Arpita; Mahadevan, Suvrath; Wang, Sharon X.; Fleming, Scott W. [Center for Exoplanets and Habitable Worlds, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA 16802 (United States); Ford, Eric B.; Payne, Matt; Lee, Brian L.; Ge, Jian [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611-2055 (United States); Wang, Ji [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Crepp, Justin R. [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556-5670 (United States); Gaudi, B. Scott; Eastman, Jason [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Pepper, Joshua; Cargile, Phillip; Stassun, Keivan G. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Ghezzi, Luan [Observatorio Nacional, Rua General Jose Cristino, 77, Rio de Janeiro, RJ 20921-400 (Brazil); Gonzalez-Hernandez, Jonay I. [Instituto de Astrofisica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain); Wisniewski, John [HL Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W Brooks St, Norman, OK 73019 (United States); Dutra-Ferreira, Leticia, E-mail: jtwright@astro.psu.edu [Laboratorio Interinstitucional de e-Astronomia (LIneA), Rua General Jose Cristino 77, Rio de Janeiro, RJ 20921-400 (Brazil); and others

    2013-06-20

    We have analyzed new and previously published radial velocity (RV) observations of MARVELS-1, known to have an ostensibly substellar companion in a {approx}6 day orbit. We find significant ({approx}100 m s{sup -1}) residuals to the best-fit model for the companion, and these residuals are naievely consistent with an interior giant planet with a P = 1.965 days in a nearly perfect 3:1 period commensurability (|P{sub b} /P{sub c} - 3| < 10{sup -4}). We have performed several tests for the reality of such a companion, including a dynamical analysis, a search for photometric variability, and a hunt for contaminating stellar spectra. We find many reasons to be critical of a planetary interpretation, including the fact that most of the three-body dynamical solutions are unstable. We find no evidence for transits, and no evidence of stellar photometric variability. We have discovered two apparent companions to MARVELS-1 with adaptive optics imaging at Keck; both are M dwarfs, one is likely bound, and the other is likely a foreground object. We explore false-alarm scenarios inspired by various curiosities in the data. Ultimately, a line profile and bisector analysis lead us to conclude that the {approx}100 m s{sup -1} residuals are an artifact of spectral contamination from a stellar companion contributing {approx}15%-30% of the optical light in the system. We conclude that origin of this contamination is the previously detected RV companion to MARVELS-1, which is not, as previously reported, a brown dwarf, but in fact a G dwarf in a face-on orbit.

  16. BioSearch Marinelife Observer Program for the Northern Mariana Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — BioSearch is a volunteer monitoring program targeting recreational divers and boaters and designed to gather information about occurrences of large or rare...

  17. A Functional Programming Approach to AI Search Algorithms

    Science.gov (United States)

    Panovics, Janos

    2012-01-01

    The theory and practice of search algorithms related to state-space represented problems form the major part of the introductory course of Artificial Intelligence at most of the universities and colleges offering a degree in the area of computer science. Students usually meet these algorithms only in some imperative or object-oriented language…

  18. Arc-Search Infeasible Interior-Point Algorithm for Linear Programming

    OpenAIRE

    Yang, Yaguang

    2014-01-01

    Mehrotra's algorithm has been the most successful infeasible interior-point algorithm for linear programming since 1990. Most popular interior-point software packages for linear programming are based on Mehrotra's algorithm. This paper proposes an alternative algorithm, arc-search infeasible interior-point algorithm. We will demonstrate, by testing Netlib problems and comparing the test results obtained by arc-search infeasible interior-point algorithm and Mehrotra's algorithm, that the propo...

  19. UCLA's Institute for Planets and Exoplanets: Structuring an Education and Public Outreach Program from the Ground Up

    Science.gov (United States)

    Curren, I. S.; Jewitt, D. C.

    2014-12-01

    Geoscience education and public outreach efforts (EPO), both formal and informal, are critical to increasing science literacy amongst members of the public and securing the next generation of geoscientists. At UCLA, the Institute for Planets and Exoplanets (iPLEX) has developed a multifaceted program to administer meaningful and original hands-on education and outreach to the public, teachers/professors, and students. To build the program, we first developed a virtual "home base" using Wordpress. With the needs of our community in mind, we structured the website to serve three categories of individuals: the public, teachers/professors, and volunteers. To serve the public, we have developed a series of informal education events (e.g., Exploring Your Universe) that bring thousands of science enthusiasts to campus. For those unable to participate in hands-on demonstrations or for those who would like to see them again, informational videos were developed and made available on our online Physical Demonstrations Digital Library (PDDL). The PDDL contains a second set of videos that are tutorial in nature and specifically designed with teachers, TAs and professors in mind. In addition, we have produced a publicly available annual newsletter written at the level of the informed public that details exciting and current planetary research at UCLA. Another facet of the program, designed with teachers in mind is our application-based private outreach event system in which teachers may choose to have volunteers come to their school with interactive demos or to come to UCLA to speak with scientists and tour laboratories. The final branch of the iPLEX EPO and education program caters to volunteers and includes an online "hub" where volunteers can register for events, download demonstration information packets, and discuss tips with other volunteers. We have recently developed a "Science Education, Outreach, and Communication" course to be integrated into UCLA's undergraduate

  20. Earth-Like Exoplanets: The Science of NASA's Navigator Program

    Science.gov (United States)

    Lawson, Peter R. (Editor); Traub, Wesley A. (Editor)

    2006-01-01

    This book outlines the exoplanet science content of NASA's Navigator Program, and it identifies the exoplanet research priorities. The goal of Navigator Program missions is to detect and characterize Earth-like planets in the habitable zone of nearby stars and to search for signs of life on those planets.

  1. Students Discover Unique Planet

    Science.gov (United States)

    2008-12-01

    Three undergraduate students, from Leiden University in the Netherlands, have discovered an extrasolar planet. The extraordinary find, which turned up during their research project, is about five times as massive as Jupiter. This is also the first planet discovered orbiting a fast-rotating hot star. Omega Centauri ESO PR Photo 45a/08 A planet around a hot star The students were testing a method of investigating the light fluctuations of thousands of stars in the OGLE database in an automated way. The brightness of one of the stars was found to decrease for two hours every 2.5 days by about one percent. Follow-up observations, taken with ESO's Very Large Telescope in Chile, confirmed that this phenomenon is caused by a planet passing in front of the star, blocking part of the starlight at regular intervals. According to Ignas Snellen, supervisor of the research project, the discovery was a complete surprise. "The project was actually meant to teach the students how to develop search algorithms. But they did so well that there was time to test their algorithm on a so far unexplored database. At some point they came into my office and showed me this light curve. I was completely taken aback!" The students, Meta de Hoon, Remco van der Burg, and Francis Vuijsje, are very enthusiastic. "It is exciting not just to find a planet, but to find one as unusual as this one; it turns out to be the first planet discovered around a fast rotating star, and it's also the hottest star found with a planet," says Meta. "The computer needed more than a thousand hours to do all the calculations," continues Remco. The planet is given the prosaic name OGLE2-TR-L9b. "But amongst ourselves we call it ReMeFra-1, after Remco, Meta, and myself," says Francis. The planet was discovered by looking at the brightness variations of about 15 700 stars, which had been observed by the OGLE survey once or twice per night for about four years between 1997 and 2000. Because the data had been made public

  2. In search of meaning: A reminiscence program for older persons

    NARCIS (Netherlands)

    Westerhof, G.J.; Bohlmeijer, E.T.; Valenkamp, M.W.

    2004-01-01

    A pilot evaluation is reported of a reminiscence program aimed at increasing personal meaning. Fifty-seven older persons completed both a sentence completion questionnaire measuring personal meaning and a depression scale administered before and after the program. In comparison to a group from a rep

  3. Characterizing the Habitable Zone Planets of Kepler Stars

    Science.gov (United States)

    Fischer, Debra

    than 100 days or they use extrapolation to estimate planet occurrence rates beyond 100 days. The new detections of transit candidates at wider separations and the incompleteness analysis will be used to carry out an analysis of the architecture of exoplanetary systems from 1 5 AU. We are synthesizing a statistical description with information from short-period Kepler transits, the longer period Kepler transit candidates from this proposal, a completeness analysis of radial velocity data, and statistical information from microlensing. While our architecture analysis will only sketch out the bare bones of planetary systems (massive or large planets), this is still a novel analysis that may point to the location of rocky planets if packed planetary systems prevail. Finally, we will expand our guest scientist program for serendipitous discoveries. We have already partnered with scientists who are searching for cataclysmic variables, heartbeat stars, and exomoons. Our undergrad students have already carried out summer research as guest scientists to characterize inflated jupiters, search for Trojan planets, and to search for microlensing events.

  4. Deciphering Spectral Fingerprints of Habitable Extrasolar Planets

    CERN Document Server

    Kaltenegger, L; Fridlund, M; Lammer, H; Beichman, Ch; Danchi, W; Eiroa, C; Henning, T; Herbst, T; Léger, A; Liseau, R; Lunine, J; Paresce, F; Penny, A; Quirrenbach, A; Roettgering, H; Schneider, J; Stam, D; Tinetti, G; White, G J

    2009-01-01

    In this paper we discuss how we can read a planets spectrum to assess its habitability and search for the signatures of a biosphere. After a decade rich in giant exoplanet detections, observation techniques have now reached the ability to find planets of less than 10 MEarth (so called Super-Earths) that may potentially be habitable. How can we characterize those planets and assess if they are habitable? The new field of extrasolar planet search has shown an extraordinary ability to combine research by astrophysics, chemistry, biology and geophysics into a new and exciting interdisciplinary approach to understand our place in the universe. The results of a first generation mission will most likely result in an amazing scope of diverse planets that will set planet formation, evolution as well as our planet in an overall context.

  5. Planet Hunters: A Status Report

    Science.gov (United States)

    Schwamb, Megan E.; Orosz, J. A.; Carter, J. A.; Fischer, D. A.; Howard, A. W.; Crepp, J. R.; Welsh, W. F.; Kaib, N. A.; Lintott, C. J.; Terrell, D.; Jek, K. J.; Gagliano, R.; Parrish, M.; Smith, A. M.; Lynn, S.; Brewer, J. M.; Giguere, M. J.; Schawinski, K.; Simpson, R. J.

    2012-10-01

    The Planet Hunters (http://www.planethunters.org) citizen science project uses the power of human pattern recognition via the World Wide Web to identify transits in the Kepler public data. Planet Hunters uses the Zooniverse (http://www.zooniverse.org) platform to present visitors to the Planet Hunters website with a randomly selected 30-day light curve segment from one of Kepler's 160,000 target stars. Volunteers are asked to draw boxes to mark the locations of visible transits with multiple independent classifiers reviewing each 30-day light curve segment. Since December 2010, more than 170,000 members of the general public have participated in Planet Hunters contributing over 12.5 million classifications searching the 1 1/2 years of publicly released Kepler observations. Planet Hunters is a novel and complementary technique to the automated transit detection algorithms, providing an independent assessment of the completeness of the Kepler exoplanet inventory. We report the latest results from Planet Hunters, highlighting in particular our latest efforts to search for circumbinary planets (planets orbiting a binary star) and single transit events in the first 1.5 years of public Kepler data. We will present a status report of our search of the first 6 Quarters of Kepler data, introducing our new planet candidates and sharing the results of our observational follow-up campaign to characterize these planetary systems. Acknowledgements: MES is supported by a NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-1003258. This is research is supported in part by an American Philosophical Society Franklin Grant.

  6. The Time-Synchronous Dynamic Programming Approach to the Shortest Path Search in Spoken Dialog System

    Institute of Scientific and Technical Information of China (English)

    HEWei; YANGSuqiong; YUANBaozong; LINBiqin

    2004-01-01

    Shortest path search has important practical applications and is related to optimization problem.This paper discusses a new algorithm time-synchronous heuristic dynamic programming search, which combined the pruning and global optimization of DP (Dynamic programming) and the partial search of heuristic strategy and found the shortest path in time O(n/kd) (k, d ≥ 1). Furthermore, the algorithm can be applied to find the K shortest paths between a pair of given nodes or all paths less than a given length within the same steps. Finally this algorithm was applied to the shortest path search on the real map and user could use spoken dialog to query shortcut in realtime, 90% of the system responses are correct.

  7. The Pan-Pacific Planet Search. IV. Two super-Jupiters in a 3:5 resonance orbiting the giant star HD33844

    CERN Document Server

    Wittenmyer, Robert A; Butler, R P; Horner, Jonathan; Wang, Liang; Robertson, Paul; Jones, M I; Jenkins, J S; Brahm, R; Tinney, C G; Mengel, M W; Clark, J

    2015-01-01

    We report the discovery of two giant planets orbiting the K giant HD 33844 based on radial velocity data from three independent campaigns. The planets move on nearly circular orbits with semimajor axes $a_b=1.60\\pm$0.02 AU and $a_c=2.24\\pm$0.05 AU, and have minimum masses (m sin $i$) of $M_b=1.96\\pm$0.12 Mjup and $M_c=1.76\\pm$0.18 Mjup. Detailed N-body dynamical simulations show that the two planets remain on stable orbits for more than $10^6$ years for low eccentricities, and are most likely trapped in a mutual 3:5 mean-motion resonance.

  8. Installation Restoration Program. Phase 1, Records Search. Chanute AFB, Illinois

    Science.gov (United States)

    1983-12-01

    silty till HilIlery / I brow.n, reddish brown till ,nbr / \\ Silty till KANSAN jr, Harmnato _ __ _ _ STAGE Z0 till .nbr / Gray, olive gray silty till...industrial coke, distillery, tannery, poultry , meat, automotive, forging, plating, paper, plastic and aluminum operations. Responsibili- ties included studies...for a county landfill in Florida. Conducted quality management, hydrogeologic and ground-water quality programs for the pulp and paper industry at

  9. Mars Atmosphere and Volatile EvolutioN (MAVEN) mission's Red Planet program: Bridging the gap in elementary school science through climate studies of Mars

    Science.gov (United States)

    Wood, E. L.

    2012-12-01

    Although reading, writing, and math examinations are often conducted early in elementary school, science is not typically tested until 4th or 5th grade. The result is a refocus on the tested topics at the expense of the untested ones, despite that standards exist for each topic at all grades. On a national level, science instruction is relegated to a matter of a few hours per week. A 2007 Education Policy study states that elementary school students spend an average of 178 minutes a week on science while spending 500 minutes on literacy. A recent NSTA report in July of 2011 of elementary and middle school teachers confirms that teachers feel pressured to teach math and literacy at the expense of other programs. In our interaction with elementary teachers, it is also apparent that many are uncomfortable with science concepts. In order for us to successfully address the Next Generation Science Standards, teachers must be able to reconcile all of the different requirements placed on them in a given school day and in a given school environment. A unique way to combat the lack of science instruction at elementary grades is to combine literacy into an integrated science program, thereby increasing the number of science contact hours. The Red Planet: Read, Write, Explore program, developed for the MAVEN mission, is a science, art, and literacy program designed to easily fit into a typical 3rd-5th grade instructional day. Red Planet tackles climate change through Mars' geologic history and makes Mars-Earth comparisons, while encouraging students to reflect on the environmental requirements needed to keep a biological organisms (including humans) happy, healthy, and alive. The Red Planet program is currently being pilot tested at Acres Green Elementary School in Colorado.

  10. Characterizing Habitable Extrasolar Planets using Spectral Fingerprints

    CERN Document Server

    Kaltenegger, L

    2009-01-01

    The detection and characterization of Earth-like planet is approaching rapidly thanks to radial velocity surveys (HARPS), transit searches (Corot, Kepler) and space observatories dedicated to their characterization are already in development phase (James Webb Space Telescope), large ground based telescopes (ELT, TNT, GMT), and dedicated space-based missions like Darwin, Terrestrial Planet Finder, New World Observer). In this paper we discuss how we can read a planets spectrum to assess its habitability and search for the signatures of a biosphere. Identifying signs of life implies understanding how the observed atmosphere physically and chemically works and thus to gather information on the planet in addition to the observing its spectral fingerprint.

  11. Giant Planets

    CERN Document Server

    Guillot, Tristan

    2014-01-01

    We review the interior structure and evolution of Jupiter, Saturn, Uranus and Neptune, and giant exoplanets with particular emphasis on constraining their global composition. Compared to the first edition of this review, we provide a new discussion of the atmospheric compositions of the solar system giant planets, we discuss the discovery of oscillations of Jupiter and Saturn, the significant improvements in our understanding of the behavior of material at high pressures and the consequences for interior and evolution models. We place the giant planets in our Solar System in context with the trends seen for exoplanets.

  12. The Problem of Extraterrestrial Civilizations and Extrasolar Planets

    Science.gov (United States)

    Mickaelian, A. M.

    2015-07-01

    The problem of extraterrestrial intelligence is the best example of multidisciplinary science. Here philosophy and religion, astronomy, radiophysics, spectrography, space flights and astronautics, geology and planetology, astroecology, chemistry and biology, history and archaeology, psychology, sociology, linguistics, diplomacy, UFOs and peculiar phenomena are involved. Among these many-sided studies, astronomers have probably displayed the most progress by discovering thousands of extrasolar planets. At present, a number of search programs are being accomplished, including those with space telescopes, and planets in so-called "habitable zone" are considered as most important ones, for which various orbital and physical parameters are being calculated. As the discovery of extraterrestrial life is the final goal, a special attention is given to Earth-like planets, for the discovery of which most sensitive technical means are necessary.

  13. Jamaica: a middle-aged program searches for new horizons.

    Science.gov (United States)

    1984-01-01

    The advertising and marketing consultant for Jamaica's Commercial Distribution of Contraceptives (JCDC) program, states that the program has reached a state of maturity that has resulted in some inertia. Although still the leader among contraceptive social marketing (CSM) programs in reaching the greatest percentage of its target market, product sales are no longer on an upswing, and retail outlets are not increasing in number. The project is hoping that the introduction of a new thin condom can help, but more than 1 new product may be needed to recapture momentum. The JCDC began in 1974 when Westinghouse Health Systems won a 3 year Agency for International Development (AID) award to create a Jamaican CSM program. Challenges facing the new social marketing project included: oral contraceptives (OCs) were sold only by prescription; most pharmacies were located in urban areas; many consumers associated condoms with prostitution and disease; and retailers were reluctant to carry contraceptives and ignorant of OC side effects. The 1st breakthrough came when Westinghouse obtained government permission to sell a project pill without prescription. After market research, project managers chose the name "Perle" for the JCDC's pill, manufactured in the US by Syntex as Noriday. "Panther" became the project's condom. Prices were set at US17 cents for a Panther 3-pack and 34 cents for a Perle cycle. Advertising messages appeared on television, radio, bus shelters, cinema screens, billboards, and point of purchase displays. By the end of the 1st year's sales, a soft goods manufacturer had asked permission to produce Panther T-shirts and a Reggae composer had popularized songs about the product. Such promotional tactics boosted sales of all contraceptives on the island. About 690,000 Panther condoms and 450,000 other brands were sold in 1976; 195,000 Perle cycles were purchased compared with 135,000 cycles for all other brands combined. By 1977, Westinghouse was reducing

  14. The Penn State - Toruń Centre for Astronomy Planet Search stars. II. Lithium abundance analysis of the red giant clump sample

    Science.gov (United States)

    Adamów, M.; Niedzielski, A.; Villaver, E.; Wolszczan, A.; Nowak, G.

    2014-09-01

    Context. Standard stellar evolution theory does not predict existence of Li-rich giant stars. Several mechanisms for Li-enrichment have been proposed to operate at certain locations inside some stars. The actual mechanism operating in real stars is still unknown. Aims: Using the sample of 348 stars from the Penn State - Toruń Centre for Astronomy Planet Search, for which uniformly determined atmospheric parameters are available, with chemical abundances and rotational velocities presented here, we investigate various channels of Li enrichment in giants. We also study Li-overabundant giants in more detail in search for origin of their peculiarities. Methods: Our work is based on the Hobby-Eberly Telescope spectra obtained with the High Resolution Spectrograph, which we use for determination of abundances and rotational velocities. The Li abundance was determined from the 7Li λ670.8 nm line, while we use a more extended set of lines for α-elements abundances. In a series of Kolmogorov-Smirnov tests, we compare Li-overabundant giants with other stars in the sample. We also use available IR photometric and kinematical data in search for evidence of mass-loss. We investigate properties of the most Li-abundant giants in more detail by using multi-epoch precise radial velocities. Results: We present Li and α-elements abundances, as well as rotational velocities for 348 stars. We detected Li in 92 stars, of which 82 are giants. Eleven of them show significant Li abundance A(Li)NLTE> 1.4 and seven of them are Li-overabundant objects, according to common criterion of A(Li) > 1.5 and their location on HR diagram, including TYC 0684-00553-1 and TYC 3105-00152-1, which are two giants with Li abundances close to meteoritic level. For another 271 stars, upper limits of Li abundance are presented. We confirmed three objects with increased stellar rotation. We show that Li-overabundant giants are among the most massive stars from our sample and show larger than average

  15. Pluto: Planet or "Dwarf Planet"?

    Science.gov (United States)

    Voelzke, M. R.; de Araújo, M. S. T.

    2010-09-01

    In August 2006 during the XXVI General Assembly of the International Astronomical Union (IAU), taken place in Prague, Czech Republic, new parameters to define a planet were established. According to this new definition Pluto will be no more the ninth planet of the Solar System but it will be changed to be a "dwarf planet". This reclassification of Pluto by the academic community clearly illustrates how dynamic science is and how knowledge of different areas can be changed and evolves through the time, allowing to perceive Science as a human construction in a constant transformation, subject to political, social and historical contexts. These epistemological characteristics of Science and, in this case, of Astronomy, constitute important elements to be discussed in the lessons, so that this work contributes to enable Science and Physics teachers who perform a basic education to be always up to date on this important astronomical fact and, thereby, carry useful information to their teaching.

  16. Automatic programming via iterated local search for dynamic job shop scheduling.

    Science.gov (United States)

    Nguyen, Su; Zhang, Mengjie; Johnston, Mark; Tan, Kay Chen

    2015-01-01

    Dispatching rules have been commonly used in practice for making sequencing and scheduling decisions. Due to specific characteristics of each manufacturing system, there is no universal dispatching rule that can dominate in all situations. Therefore, it is important to design specialized dispatching rules to enhance the scheduling performance for each manufacturing environment. Evolutionary computation approaches such as tree-based genetic programming (TGP) and gene expression programming (GEP) have been proposed to facilitate the design task through automatic design of dispatching rules. However, these methods are still limited by their high computational cost and low exploitation ability. To overcome this problem, we develop a new approach to automatic programming via iterated local search (APRILS) for dynamic job shop scheduling. The key idea of APRILS is to perform multiple local searches started with programs modified from the best obtained programs so far. The experiments show that APRILS outperforms TGP and GEP in most simulation scenarios in terms of effectiveness and efficiency. The analysis also shows that programs generated by APRILS are more compact than those obtained by genetic programming. An investigation of the behavior of APRILS suggests that the good performance of APRILS comes from the balance between exploration and exploitation in its search mechanism.

  17. Advances in the Kepler Transit Search Engine

    Science.gov (United States)

    Jenkins, Jon M.

    2016-10-01

    Twenty years ago, no planets were known outside our own solar system. Since then, the discoveries of ~1500 exoplanets have radically altered our views of planets and planetary systems. This revolution is due in no small part to the Kepler Mission, which has discovered >1000 of these planets and >4000 planet candidates. While Kepler has shown that small rocky planets and planetary systems are quite common, the quest to find Earth's closest cousins and characterize their atmospheres presses forward with missions such as NASA Explorer Program's Transiting Exoplanet Survey Satellite (TESS) slated for launch in 2017 and ESA's PLATO mission scheduled for launch in 2024. These future missions pose daunting data processing challenges in terms of the number of stars, the amount of data, and the difficulties in detecting weak signatures of transiting small planets against a roaring background. These complications include instrument noise and systematic effects as well as the intrinsic stellar variability of the subjects under scrutiny. In this paper we review recent developments in the Kepler transit search pipeline improving both the yield and reliability of detected transit signatures. Many of the phenomena in light curves that represent noise can also trigger transit detection algorithms. The Kepler Mission has expended great effort in suppressing false positives from its planetary candidate catalogs. Over 18,000 transit-like signatures can be identified for a search across 4 years of data. Most of these signatures are artifacts, not planets. Vetting all such signatures historically takes several months' effort by many individuals. We describe the application of machine learning approaches for the automated vetting and production of planet candidate catalogs. These algorithms can improve the efficiency of the human vetting effort as well as quantifying the likelihood that each candidate is truly a planet. This information is crucial for obtaining valid planet occurrence

  18. United States medical school graduate interest in radiology residency programs as depicted by online search tools.

    Science.gov (United States)

    Haney, Nora M; Kinsella, Stuart D; Morey, José M

    2014-02-01

    Recent media publications have indicated a tough job market in medical specialty positions for medical school graduates, specifically in the field of radiology. Internet search tools, such as Google Trends, have proved useful in the prediction of certain diseases on the basis of the search volume index for a specific term. The authors hypothesized that online search tools might be useful in the prediction of US medical school graduates' interest in residency positions in radiology. Google Trends indicated an increase over time in searches for "radiology salary" and a decrease over time in searches for "radiology residency." National Resident Matching Program results for diagnostic radiology showed an increase from 2004 to 2009 in the percentage of US graduates entering radiology but a dramatic drop from 2010 to 2013. This occurred even while the total number of US graduates active in the National Resident Matching Program increased. This finding might have been foretold on the basis of online query result trends. Online search data may be a useful insight into the interests of US medical school graduates and may be predictive of unfilled radiology residency positions and eventual increased shortages of community radiologists coming from US medical schools.

  19. A New Family of Planets ? "Ocean Planets"

    OpenAIRE

    Leger, A.; Selsis, F.; Sotin, C.; Guillot, T.; Despois, D.; Lammer, H.; Ollivier, M.; Brachet, F.; Labeque, A.; Valette, C.

    2003-01-01

    A new family of planets is considered which is between rochy terrestrial planets and gaseous giant ones: "Ocean-Planets". We present the possible formation, composition and internal models of these putative planets, including that of their ocean, as well as their possible Exobiology interest. These planets should be detectable by planet detection missions such as Eddington and Kepler, and possibly COROT (lauch scheduled in 2006). They would be ideal targets for spectroscopic missions such as ...

  20. Methods and means used in programming intelligent searches of technical documents

    Science.gov (United States)

    Gross, David L.

    1993-01-01

    In order to meet the data research requirements of the Safety, Reliability & Quality Assurance activities at Kennedy Space Center (KSC), a new computer search method for technical data documents was developed. By their very nature, technical documents are partially encrypted because of the author's use of acronyms, abbreviations, and shortcut notations. This problem of computerized searching is compounded at KSC by the volume of documentation that is produced during normal Space Shuttle operations. The Centralized Document Database (CDD) is designed to solve this problem. It provides a common interface to an unlimited number of files of various sizes, with the capability to perform any diversified types and levels of data searches. The heart of the CDD is the nature and capability of its search algorithms. The most complex form of search that the program uses is with the use of a domain-specific database of acronyms, abbreviations, synonyms, and word frequency tables. This database, along with basic sentence parsing, is used to convert a request for information into a relational network. This network is used as a filter on the original document file to determine the most likely locations for the data requested. This type of search will locate information that traditional techniques, (i.e., Boolean structured key-word searching), would not find.

  1. Planet Hunters: Assessing the Kepler Inventory of Short Period Planets

    CERN Document Server

    Schwamb, Megan E; Fischer, Debra A; Giguere, Matthew J; Lynn, Stuart; Smith, Arfon M; Brewer, John M; Parrish, Michael; Schawinski, Kevin; Simpson, Robert J

    2012-01-01

    We present the results from a search of data from the first 33.5 days of the Kepler science mission (Quarter 1) for exoplanet transits by the Planet Hunters citizen science project. Planet Hunters enlists members of the general public to visually identify transits in the publicly released Kepler light curves via the World Wide Web. Over 24,000 volunteers reviewed the Kepler Quarter 1 data set. We examine the abundance of \\geq 2 R\\oplus planets on short period (< 15 days) orbits based on Planet Hunters detections. We present these results along with an analysis of the detection efficiency of human classifiers to identify planetary transits including a comparison to the Kepler inventory of planet candidates. Although performance drops rapidly for smaller radii, \\geq 4 R\\oplus Planet Hunters \\geq 85% efficient at identifying transit signals for planets with periods less than 15 days for the Kepler sample of target stars. Our high efficiency rate for simulated transits along with recovery of the majority of Ke...

  2. Information Search Process: A Summary of Research and Implications for School Library Media Programs.

    Science.gov (United States)

    Kuhlthau, Carol C.

    1989-01-01

    Summarizes a series of five studies on students' perspectives of information seeking in response to a research assignment. Feelings, thoughts, and actions commonly experienced in the information search process are described in six stages. Implications of the findings for further research and their impact on school library media programs are…

  3. 34 CFR 643.1 - What is the Talent Search program?

    Science.gov (United States)

    2010-07-01

    ... potential for education at the postsecondary level and encourage them to complete secondary school and... 34 Education 3 2010-07-01 2010-07-01 false What is the Talent Search program? 643.1 Section 643.1 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF...

  4. Exoplanets search and characterization with the SOPHIE spectrograph at OHP

    Directory of Open Access Journals (Sweden)

    Hébrard G.

    2011-02-01

    Full Text Available Several programs of exoplanets search and characterization have been started with SOPHIE at the 1.93-m telescope of Haute-Provence Observatory, France. SOPHIE is an environmentally stabilized echelle spectrograph dedicated to high-precision radial velocity measurements. The objectives of these programs include systematic searches for exoplanets around different types of stars, characterizations of planet-host stars, studies of transiting planets through RossiterMcLaughlin effect, follow-up observations of photometric surveys. The instrument SOPHIE and a review of its latest results are presented here.

  5. The HARPS search for southern extra-solar planets. XXX. Planetary systems around stars with solar-like magnetic cycles and short-term activity variation

    Science.gov (United States)

    Dumusque, X.; Lovis, C.; Ségransan, D.; Mayor, M.; Udry, S.; Benz, W.; Bouchy, F.; Lo Curto, G.; Mordasini, C.; Pepe, F.; Queloz, D.; Santos, N. C.; Naef, D.

    2011-11-01

    We present the discovery of four new long-period planets within the HARPS high-precision sample: HD 137388b (Msini = 0.22 MJ), HD 204941b (Msini = 0.27 MJ), HD 7199b (Msini = 0.29 MJ), HD 7449b (Msini = 1.04 MJ). A long-period companion, probably a second planet, is also found orbiting HD 7449. Planets around HD 137388, HD 204941, and HD 7199 have rather low eccentricities (less than 0.4) relative to the 0.82 eccentricity of HD 7449b. All these planets were discovered even though their hosting stars have clear signs of activity. Solar-like magnetic cycles, characterized by long-term activity variations, can be seen for HD 137388, HD 204941 and HD 7199, whereas the measurements of HD 7449 reveal a short-term activity variation, most probably induced by magnetic features on the stellar surface. We confirm that magnetic cycles induce a long-term radial velocity variation and propose a method to reduce considerably the associated noise. The procedure consists of fitting the activity index and applying the same solution to the radial velocities because a linear correlation between the activity index and the radial velocity is found. Tested on HD 137388, HD 204941, and HD 7199, this correction reduces considerably the stellar noise induced by magnetic cycles and allows us to derive precisely the orbital parameters of planetary companions. Based on observations made with the HARPS instrument on the ESO 3.6-m telescope at La Silla Observatory (Chile), under programme IDs 072.C-0488 and 183.C-0972.Radial velocities (Tables 4-7) are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/535/A55

  6. The HARPS search for southern extra-solar planets. XXXVII. Bayesian re-analysis of three systems. New super-Earths, unconfirmed signals, and magnetic cycles

    CERN Document Server

    Díaz, R F; Udry, S; Lovis, C; Pepe, F; Dumusque, X; Marmier, M; Alonso, R; Benz, W; Bouchy, F; Coffinet, A; Cameron, A Collier; Deleuil, M; Figueira, P; Gillon, M; Curto, G Lo; Mayor, M; Mordasini, C; Motalebi, F; Moutou, C; Pollacco, D; Pompei, E; Queloz, D; Santos, N; Wyttenbach, A

    2016-01-01

    We present the analysis of the entire HARPS observations of three stars that host planetary systems: HD1461, HD40307, and HD204313. The data set spans eight years and contains more than 200 nightly averaged velocity measurements for each star. This means that it is sensitive to both long-period and low-mass planets and also to the effects induced by stellar activity cycles. We modelled the data using Keplerian functions that correspond to planetary candidates and included the short- and long-term effects of magnetic activity. A Bayesian approach was taken both for the data modelling, which allowed us to include information from activity proxies such as $\\log{(R'_{\\rm HK})}$ in the velocity modelling, and for the model selection, which permitted determining the number of significant signals in the system. The Bayesian model comparison overcomes the limitations inherent to the traditional periodogram analysis. We report an additional super-Earth planet in the HD1461 system. Four out of the six planets previousl...

  7. The HARPS search for southern extra-solar planets: XIV. Gl 176b, a super-Earth rather than a Neptune, and at a different period

    CERN Document Server

    Forveille, T; Delfosse, X; Gillon, M; Udry, S; Bouchy, F; Lovis, C; Mayor, M; Pepe, F; Perrier, C; Queloz, D; Santos, N; Bertaux, J -L

    2008-01-01

    A 10.24 days Neptune-mass planet was recently announced to orbit the nearby M2 dwarf Gl 176, based on 28 radial velocities measured with the HRS spectrograph on the Hobby-Heberly Telescope (HET). We obtained 57 radial velocities of Gl 176 with the ESO 3.6m telescope and the HARPS spectrograph, which is known for its sub-m/s stability. The median photon-noise standard error of our measurements is 1.1 m/s, significantly lower than the 4.7 m/s of the HET velocities, and the 4 years period over which they were obtained has much overlap with the epochs of the HET measurements. The HARPS measurements show no evidence for a signal at the period of the putative HET planet, suggesting that its detection was spurious. We do find, on the other hand, strong evidence for a lower mass 8.4 Mearth planet, in a quasi-circular orbit and at the different period of 8.78 days. The host star has moderate magnetic activity and rotates on a 39-days period, which we confirm through modulation of both contemporaneous photometry and ch...

  8. Formation, Survival, and Detectability of Planets Beyond 100 AU

    CERN Document Server

    Veras, Dimitri; Ford, Eric B

    2009-01-01

    Direct imaging searches have begun to detect planetary and brown dwarf companions and to place constraints on the presence of giant planets at large separations from their host star. This work helps to motivate such planet searches by predicting a population of young giant planets that could be detectable by direct imaging campaigns. Both the classical core accretion and the gravitational instability model for planet formation are hard-pressed to form long-period planets in situ. Here, we show that dynamical instabilities among planetary systems that originally formed multiple giant planets much closer to the host star could produce a population of giant planets at large (~100 AU - 100000 AU) separations. We estimate the limits within which these planets may survive, quantify the efficiency of gravitational scattering into both stable and unstable wide orbits, and demonstrate that population analyses must take into account the age of the system. We predict that planet scattering creates a population of detect...

  9. Terrestrial Planet Finder Interferometer Science Working Group Report

    Science.gov (United States)

    Lawson, Peter R. (Editor); Lay, Oliver P. (Editor); Johnston, Kenneth J. (Editor); Beichman, Charles A. (Editor)

    2007-01-01

    Over the past two years, the focus of the project for the interferometric version of the Terrestrial Planet Finder(TPF-I) has been on the development of the scientific rational for the mission, the assessment of TPF-I architectures, the laboratory demonstration of key technologies, and the development of a detailed technology roadmap. The Science Working Group (SWG), in conjunction with European colleagues working on the European Space Agency's (ESA's) Darwin project, has reaffirmed the goals of TPF-I as part of a broad vision for the detection and characterization of Earth-like planets orbiting nearby stars and for the search for life on those planets. The SWG also helped to assess the performance of different interferometric configurations for TPF-I/Darwin. Building on earlier SWG reports, this document restates the scientific case for TPF-I, assesses suitable target stars and relevant wavelengths for observation, discusses dramatic new capabilities for general astrophysical observations, and summarizes how Spitzer has improved our knowledge of the incidence of zodiacal emission on the search for planets. This document discusses in some detail on laboratory advances in interferometric nulling and formation flying. Laboratory experiments have now achieved stable narrow- and broad-band nulling the levels of 10-6 and 2.0x10-5, respectively. A testbed has demonstrated formation flying using two realistic spacecraft mockups. With a suitably funded program of technology development, as summarized herein and described in more detail in the Technology Plan for the Terrestrial Planet Finder Interferometer (2005), the National Aeronautics and Space Administration (NASA) and ESA would be able to start within the coming decade a full-scale TPF-I/Darwin mission capable of finding Earths orbiting more than 150 nearby stars, or a scaled back interferometer capable of studying more than 30 stars. Finding evidence for life on just one of those planets would revolutionize our

  10. Astronomers find distant planet like Jupiter

    CERN Multimedia

    2003-01-01

    Astronomers searching for planetary systems like our solar system have found a planet similar to Jupiter orbiting a nearby star similar to our Sun, about 90 light-years from Earth, according to researchers (1/2 page).

  11. An Update on Planet Nine

    Science.gov (United States)

    Kohler, Susanna

    2016-07-01

    Whats the news coming from the research world on the search for Planet Nine? Read on for an update from a few of the latest studies.Artists illustration of Planet Nine, a hypothesized Neptune-sized planet orbiting in the distant reaches of our solar system. [Caltech/Robert Hurt]What is Planet Nine?In January of this year, Caltech researchers Konstantin Batygin and Mike Brown presented evidence of a distant ninth planet in our solar system. They predicted this planet to be of a mass and volume consistent with a super-Earth, orbiting on a highly eccentric pathwith a period of tens of thousands of years.Since Batygin and Browns prediction, scientists have been hunting for further signs of Planet Nine. Though we havent yet discovered an object matching its description, we have come up with new strategies for finding it, we set some constraints on where it might be, and we made some interesting theoretical predictions about its properties.Visualizations of the resonant orbits of the four longest-period Kuiper belt objects, depicted in a frame rotating with the mean angular velocity of Planet Nine. Planet Nines position is on the right (with the trace of possible eccentric orbits e=0.17 and e=0.4 indicated in red). [Malhotra et al 2016]Here are some of the newest constraints on Planet Nine from studies published just within the past two weeks.Resonant OrbitsRenu Malhotra (University of Arizonas Lunar and Planetary Laboratory) and collaborators present further evidence of the shaping of solar system orbits by the hypothetical Planet Nine. The authors point out that the four longest-period Kuiper belt objects (KBOs) have orbital periods close to integer ratios with each other. Could it be that these outer KBOs have become locked into resonant orbits with a distant, massive body?The authors find that a distant planet orbiting with a period of ~17,117 years and a semimajor axis ~665 AU would have N/1 and N/2 period ratios with these four objects. If this is correct, it

  12. STRATEGIES IN SEARCHING HOMOGENEITY IN A FACULTY OF A POSTGRADUATE PROGRAM

    Directory of Open Access Journals (Sweden)

    José G Cecatti

    Full Text Available The professor plays a fundamental role in a graduate program, considering he/she is who plans and performs a great part of the tasks, and he/she is also responsible for spreading knowledge among students. The professor should use didactical resources for his/her continuous qualification, being responsible for situations favoring the development of students who should learn according to the best and easier way. The homogeneity in the postgraduate program consists of having subgroups of research corresponding to the Areas of Concentration, where each subgroup works with some distinct topics of research. It is desirable that the staff of postgraduate program has a significant and high quality scientific production, homogeneously distributed among them. The professors must systematically search for resources for research in agencies supporting research, not only for sponsoring the studies, but also for adding value to the researchers involved in the whole activities. The postgraduate programs need to support the professional qualification of their staff who should improve their knowledge on epidemiology for clinical studies, ethics in research and teaching skills. Two characteristics of the postgraduate system in Brazil are the nucleation and solidarity, based on the capacity and/or interest of those more structured programs to help those beginners, cooperating with their activities. The Capes (the national governmental agency responsible for coordinating and evaluating all postgraduate programs in Brazil valorizes the social insertion in the context of postgraduate programs´ activities. It includes the recognition of activities with technological, cultural, educational and social impact as criteria for evaluation of the programs. Does exist an ideal model of postgraduate program? We think that there is no a mathematical formulae nor an ideal model for a postgraduate program. Each institution should make adaptations and search for improvements of

  13. OPUS: A Comprehensive Search Tool for Remote Sensing Observations of the Outer Planets. Now with Enhanced Geometric Metadata for Cassini and New Horizons Optical Remote Sensing Instruments.

    Science.gov (United States)

    Gordon, M. K.; Showalter, M. R.; Ballard, L.; Tiscareno, M.; French, R. S.; Olson, D.

    2017-06-01

    The PDS RMS Node hosts OPUS - an accurate, comprehensive search tool for spacecraft remote sensing observations. OPUS supports Cassini: CIRS, ISS, UVIS, VIMS; New Horizons: LORRI, MVIC; Galileo SSI; Voyager ISS; and Hubble: ACS, STIS, WFC3, WFPC2.

  14. Ground-based search for the brightest transiting planets with the Multi-site All-Sky CAmeRA - MASCARA

    CERN Document Server

    Snellen, Ignas; Navarro, Ramon; Bettonvil, Felix; Kenworthy, Matthew; de Mooij, Ernst; Otten, Gilles; ter Horst, Rik; Poole, Rudolf le

    2012-01-01

    The Multi-site All-sky CAmeRA MASCARA is an instrument concept consisting of several stations across the globe, with each station containing a battery of low-cost cameras to monitor the near-entire sky at each location. Once all stations have been installed, MASCARA will be able to provide a nearly 24-hr coverage of the complete dark sky, down to magnitude 8, at sub-minute cadence. Its purpose is to find the brightest transiting exoplanet systems, expected in the V=4-8 magnitude range - currently not probed by space- or ground-based surveys. The bright/nearby transiting planet systems, which MASCARA will discover, will be the key targets for detailed planet atmosphere observations. We present studies on the initial design of a MASCARA station, including the camera housing, domes, and computer equipment, and on the photometric stability of low-cost cameras showing that a precision of 0.3-1% per hour can be readily achieved. We plan to roll out the first MASCARA station before the end of 2013. A 5-station MASCA...

  15. Variable Neighbourhood Search and Mathematical Programming for Just-in-Time Job-Shop Scheduling Problem

    Directory of Open Access Journals (Sweden)

    Sunxin Wang

    2014-01-01

    Full Text Available This paper presents a combination of variable neighbourhood search and mathematical programming to minimize the sum of earliness and tardiness penalty costs of all operations for just-in-time job-shop scheduling problem (JITJSSP. Unlike classical E/T scheduling problem with each job having its earliness or tardiness penalty cost, each operation in this paper has its earliness and tardiness penalties, which are paid if the operation is completed before or after its due date. Our hybrid algorithm combines (i a variable neighbourhood search procedure to explore the huge feasible solution spaces efficiently by alternating the swap and insertion neighbourhood structures and (ii a mathematical programming model to optimize the completion times of the operations for a given solution in each iteration procedure. Additionally, a threshold accepting mechanism is proposed to diversify the local search of variable neighbourhood search. Computational results on the 72 benchmark instances show that our algorithm can obtain the best known solution for 40 problems, and the best known solutions for 33 problems are updated.

  16. Success of the International Year of the Planet Earth through Targeted High-impact Programs at the American Geological Institute

    Science.gov (United States)

    Leahy, P.

    2007-12-01

    The American Geological Institute (AGI) is one of the 12 founding partners of the International Year of the Planet Earth (IYPE) and as such AGI serves on its governing board. AGI is a nonprofit federation of 44 geoscientific and professional associations that represents more than 120,000 geologists, geophysicists, and other earth scientists. AGI provides information services to geoscientists, serves as a voice of shared interests in our profession, plays a major role in strengthening geoscience education, and strives to increase public awareness of the vital role the geosciences play in society's use of resources, resilience to natural hazards, and the health of the environment. The outreach and educational opportunities afforded by IYPE provide AGI with an international venue to promote the role of the geosciences in the daily life of society. AGI's successful release of the 4-part television series entitled Faces of Earth done in partnership with the Discovery Communications is a hallmark example of an outreach product that is technically accurate but designed to engage the non-scientific audience in the wonderment of our science. The series focuses on building the planet, shaping the planet, assembling America, and the human world. Custom short cuts have been produced for special purposes and one of these may be used as part of an IYPE-launch event in Europe. AGI's news magazine, Geotimes will highlight appropriate IYPE events to increase the awareness of the American geoscience community. In addition, Geotimes will promote IYPE by using its logo routinely and through publishing advertisements reminding its professional and public readership of the importance of the IYPE triennium. Similarly, as part of AGI's K-12 educational efforts and teacher training and through its development of Earth Science Week materials, the goals, accomplishments, and importance of IYPE will be incorporated into the targeted educational audiences. IYPE activities will be highlighted

  17. Five Intermediate-Period Planets from the N2K Sample

    CERN Document Server

    Fischer, Debra A; Butler, R Paul; Sato, Bun'ei; Vogt, Steven S; Robinson, Sarah; Laughlin, Gregory; Henry, Gregory W; Ida, Shigeru; Toyota, Eri; Omiya, Masashi; Driscoll, Peter; Takeda, Genya; Wright, Jason T; Johnson, John A

    2007-01-01

    We report the detection of five jovian mass planets orbiting high metallicity stars. Four of these stars were first observed as part of the N2K program and exhibited low RMS velocity scatter after three consecutive observations. However, follow-up observations over the last three years now reveal the presence of longer period planets with orbital periods ranging from 21 days to a few years. HD 11506 is a G0V star with a planet of \\msini = 4.85 \\mjup in a 3.5 year orbit. HD 17156 is a G0V star with a 3.08 \\mjup planet in an eccentric ($e = 0.67$) 21.2 day orbit. HD 125612 is a G3V star with a planet of \\msini = 3.2 \\mjup in a 1.37 year orbit. HD 170469 is a G5IV star with a planet of \\msini = 0.68 \\mjup in a 3 year orbit. HD 231701 is an F8V star with planet of 1.03 \\mjup in a 143 day orbit. All of the stars have supersolar metallicity. Three of the five stars were observed photometrically but showed no evidence of brightness variability. A transit search conducted for HD 17156 was negative but covered only 25...

  18. Planet Hunters: Assessing the Kepler Inventory of Short-period Planets

    Science.gov (United States)

    Schwamb, Megan E.; Lintott, Chris J.; Fischer, Debra A.; Giguere, Matthew J.; Lynn, Stuart; Smith, Arfon M.; Brewer, John M.; Parrish, Michael; Schawinski, Kevin; Simpson, Robert J.

    2012-08-01

    We present the results from a search of data from the first 33.5 days of the Kepler science mission (Quarter 1) for exoplanet transits by the Planet Hunters citizen science project. Planet Hunters enlists members of the general public to visually identify transits in the publicly released Kepler light curves via the World Wide Web. Over 24,000 volunteers reviewed the Kepler Quarter 1 data set. We examine the abundance of >=2 R ⊕ planets on short-period (=4 R ⊕ Planet Hunters >=85% efficient at identifying transit signals for planets with periods less than 15 days for the Kepler sample of target stars. Our high efficiency rate for simulated transits along with recovery of the majority of Kepler >=4 R ⊕ planets suggests that the Kepler inventory of >=4 R ⊕ short-period planets is nearly complete.

  19. IESIP - AN IMPROVED EXPLORATORY SEARCH TECHNIQUE FOR PURE INTEGER LINEAR PROGRAMMING PROBLEMS

    Science.gov (United States)

    Fogle, F. R.

    1994-01-01

    IESIP, an Improved Exploratory Search Technique for Pure Integer Linear Programming Problems, addresses the problem of optimizing an objective function of one or more variables subject to a set of confining functions or constraints by a method called discrete optimization or integer programming. Integer programming is based on a specific form of the general linear programming problem in which all variables in the objective function and all variables in the constraints are integers. While more difficult, integer programming is required for accuracy when modeling systems with small numbers of components such as the distribution of goods, machine scheduling, and production scheduling. IESIP establishes a new methodology for solving pure integer programming problems by utilizing a modified version of the univariate exploratory move developed by Robert Hooke and T.A. Jeeves. IESIP also takes some of its technique from the greedy procedure and the idea of unit neighborhoods. A rounding scheme uses the continuous solution found by traditional methods (simplex or other suitable technique) and creates a feasible integer starting point. The Hook and Jeeves exploratory search is modified to accommodate integers and constraints and is then employed to determine an optimal integer solution from the feasible starting solution. The user-friendly IESIP allows for rapid solution of problems up to 10 variables in size (limited by DOS allocation). Sample problems compare IESIP solutions with the traditional branch-and-bound approach. IESIP is written in Borland's TURBO Pascal for IBM PC series computers and compatibles running DOS. Source code and an executable are provided. The main memory requirement for execution is 25K. This program is available on a 5.25 inch 360K MS DOS format diskette. IESIP was developed in 1990. IBM is a trademark of International Business Machines. TURBO Pascal is registered by Borland International.

  20. Energy Consumption Forecasting Using Semantic-Based Genetic Programming with Local Search Optimizer

    Directory of Open Access Journals (Sweden)

    Mauro Castelli

    2015-01-01

    Full Text Available Energy consumption forecasting (ECF is an important policy issue in today’s economies. An accurate ECF has great benefits for electric utilities and both negative and positive errors lead to increased operating costs. The paper proposes a semantic based genetic programming framework to address the ECF problem. In particular, we propose a system that finds (quasi-perfect solutions with high probability and that generates models able to produce near optimal predictions also on unseen data. The framework blends a recently developed version of genetic programming that integrates semantic genetic operators with a local search method. The main idea in combining semantic genetic programming and a local searcher is to couple the exploration ability of the former with the exploitation ability of the latter. Experimental results confirm the suitability of the proposed method in predicting the energy consumption. In particular, the system produces a lower error with respect to the existing state-of-the art techniques used on the same dataset. More importantly, this case study has shown that including a local searcher in the geometric semantic genetic programming system can speed up the search process and can result in fitter models that are able to produce an accurate forecasting also on unseen data.

  1. Energy Consumption Forecasting Using Semantic-Based Genetic Programming with Local Search Optimizer.

    Science.gov (United States)

    Castelli, Mauro; Trujillo, Leonardo; Vanneschi, Leonardo

    2015-01-01

    Energy consumption forecasting (ECF) is an important policy issue in today's economies. An accurate ECF has great benefits for electric utilities and both negative and positive errors lead to increased operating costs. The paper proposes a semantic based genetic programming framework to address the ECF problem. In particular, we propose a system that finds (quasi-)perfect solutions with high probability and that generates models able to produce near optimal predictions also on unseen data. The framework blends a recently developed version of genetic programming that integrates semantic genetic operators with a local search method. The main idea in combining semantic genetic programming and a local searcher is to couple the exploration ability of the former with the exploitation ability of the latter. Experimental results confirm the suitability of the proposed method in predicting the energy consumption. In particular, the system produces a lower error with respect to the existing state-of-the art techniques used on the same dataset. More importantly, this case study has shown that including a local searcher in the geometric semantic genetic programming system can speed up the search process and can result in fitter models that are able to produce an accurate forecasting also on unseen data.

  2. Energy Consumption Forecasting Using Semantic-Based Genetic Programming with Local Search Optimizer

    Science.gov (United States)

    Vanneschi, Leonardo

    2015-01-01

    Energy consumption forecasting (ECF) is an important policy issue in today's economies. An accurate ECF has great benefits for electric utilities and both negative and positive errors lead to increased operating costs. The paper proposes a semantic based genetic programming framework to address the ECF problem. In particular, we propose a system that finds (quasi-)perfect solutions with high probability and that generates models able to produce near optimal predictions also on unseen data. The framework blends a recently developed version of genetic programming that integrates semantic genetic operators with a local search method. The main idea in combining semantic genetic programming and a local searcher is to couple the exploration ability of the former with the exploitation ability of the latter. Experimental results confirm the suitability of the proposed method in predicting the energy consumption. In particular, the system produces a lower error with respect to the existing state-of-the art techniques used on the same dataset. More importantly, this case study has shown that including a local searcher in the geometric semantic genetic programming system can speed up the search process and can result in fitter models that are able to produce an accurate forecasting also on unseen data. PMID:26106410

  3. K2's First Five-Planet System

    Science.gov (United States)

    Kohler, Susanna

    2016-08-01

    Whats the latest from the Kepler K2 mission? K2 has found its first planetary system containing more than three planets an exciting five-planet system located ~380 light-years from Earth!Opportunities From K2Raw K2 light curve (blue, top) and systematic corrected light curve (orange, bottom) for HIP 41378. The three deepest transits are single transits from the three outermost planet candidates. [Vanderburg et al. 2016]The original Kepler mission was enormously successful, discovering thousands of planet candidates. But one side effect of Keplers original observing technique, in which it studied the same field for four years, is that it was very good at detecting extremely faint systems systems that were often too faint to be followed up with other techniques.After Keplers mechanical failure in 2013, the K2 mission was launched, in which the spacecraft uses solar pressure to stabilize it long enough to perform an 80-day searches of each region it examines. Over the course of the K2 mission, Kepler could potentially survey up to 20 times the sky area of the original mission, providing ample opportunity to find planetary systems around bright stars. These stars may be bright enough to be followed up with other techniques.Multi-Planet SystemsTheres a catch to the 80-day observing program: the K2 mission is less likely to detect multiple planets orbiting the same star, due to the short time spent observing the system. While the original Kepler mission detected systems with up to seven planets, K2 had yet to detect systems with more than three candidates until now.Led by Andrew Vanderburg (NSF Graduate Research Fellow at the Harvard-Smithsonian Center for Astrophysics), a team of scientists recentlyanalyzed K2 observations ofthe bright star HIP 41378. Theteamfound that this F-type star hosts five potential planetary candidates!Phase-folded light curve for each of the five transiting planets in the HIP 41378 system. The outermost planet (bottom panel) may provide an

  4. MARVELS-1: A Face-on Double-lined Binary Star Masquerading as a Resonant Planetary System and Consideration of Rare False Positives in Radial Velocity Planet Searches

    Science.gov (United States)

    Wright, Jason T.; Roy, Arpita; Mahadevan, Suvrath; Wang, Sharon X.; Ford, Eric B.; Payne, Matt; Lee, Brian L.; Wang, Ji; Crepp, Justin R.; Gaudi, B. Scott; Eastman, Jason; Pepper, Joshua; Ge, Jian; Fleming, Scott W.; Ghezzi, Luan; González-Hernández, Jonay I.; Cargile, Phillip; Stassun, Keivan G.; Wisniewski, John; Dutra-Ferreira, Leticia; Porto de Mello, Gustavo F.; Maia, Márcio A. G.; Nicolaci da Costa, Luiz; Ogando, Ricardo L. C.; Santiago, Basilio X.; Schneider, Donald P.; Hearty, Fred R.

    2013-06-01

    We have analyzed new and previously published radial velocity (RV) observations of MARVELS-1, known to have an ostensibly substellar companion in a ~6 day orbit. We find significant (~100 m s-1) residuals to the best-fit model for the companion, and these residuals are naïvely consistent with an interior giant planet with a P = 1.965 days in a nearly perfect 3:1 period commensurability (|Pb /Pc - 3| MARVELS-1 with adaptive optics imaging at Keck; both are M dwarfs, one is likely bound, and the other is likely a foreground object. We explore false-alarm scenarios inspired by various curiosities in the data. Ultimately, a line profile and bisector analysis lead us to conclude that the ~100 m s-1 residuals are an artifact of spectral contamination from a stellar companion contributing ~15%-30% of the optical light in the system. We conclude that origin of this contamination is the previously detected RV companion to MARVELS-1, which is not, as previously reported, a brown dwarf, but in fact a G dwarf in a face-on orbit.

  5. System network planning expansion using mathematical programming, genetic algorithms and tabu search

    Energy Technology Data Exchange (ETDEWEB)

    Sadegheih, A. [Department of Industrial Engineering, University of Yazd, P.O. Box 89195-741, Yazd (Iran); Drake, P.R. [E-Business and Operations Management Division, University of Liverpool Management School, University of Liverpool, Liverpool (United Kingdom)

    2008-06-15

    In this paper, system network planning expansion is formulated for mixed integer programming, a genetic algorithm (GA) and tabu search (TS). Compared with other optimization methods, GAs are suitable for traversing large search spaces, since they can do this relatively rapidly and because the use of mutation diverts the method away from local minima, which will tend to become more common as the search space increases in size. GA's give an excellent trade off between solution quality and computing time and flexibility for taking into account specific constraints in real situations. TS has emerged as a new, highly efficient, search paradigm for finding quality solutions to combinatorial problems. It is characterized by gathering knowledge during the search and subsequently profiting from this knowledge. The attractiveness of the technique comes from its ability to escape local optimality. The cost function of this problem consists of the capital investment cost in discrete form, the cost of transmission losses and the power generation costs. The DC load flow equations for the network are embedded in the constraints of the mathematical model to avoid sub-optimal solutions that can arise if the enforcement of such constraints is done in an indirect way. The solution of the model gives the best line additions and also provides information regarding the optimal generation at each generation point. This method of solution is demonstrated on the expansion of a 10 bus bar system to 18 bus bars. Finally, a steady-state genetic algorithm is employed rather than generational replacement, also uniform crossover is used. (author)

  6. Direct Imaging of Warm Extrasolar Planets

    Energy Technology Data Exchange (ETDEWEB)

    Macintosh, B

    2005-04-11

    One of the most exciting scientific discoveries in the last decade of the twentieth century was the first detection of planets orbiting a star other than our own. By now more than 130 extrasolar planets have been discovered indirectly, by observing the gravitational effects of the planet on the radial velocity of its parent star. This technique has fundamental limitations: it is most sensitive to planets close to their star, and it determines only a planet's orbital period and a lower limit on the planet's mass. As a result, all the planetary systems found so far are very different from our own--they have giant Jupiter-sized planets orbiting close to their star, where the terrestrial planets are found in our solar system. Such systems have overturned the conventional paradigm of planet formation, but have no room in them for habitable Earth-like planets. A powerful complement to radial velocity detections of extrasolar planets will be direct imaging--seeing photons from the planet itself. Such a detection would allow photometric measurements to determine the temperature and radius of a planet. Also, direct detection is most sensitive to planets in wide orbits, and hence more capable of seeing solar systems resembling our own, since a giant planet in a wide orbit does not preclude the presence of an Earth-like planet closer to the star. Direct detection, however, is extremely challenging. Jupiter is roughly a billion times fainter than our sun. Two techniques allowed us to overcome this formidable contrast and attempt to see giant planets directly. The first is adaptive optics (AO) which allows giant earth-based telescopes, such as the 10 meter W.M. Keck telescope, to partially overcome the blurring effects of atmospheric turbulence. The second is looking for young planets: by searching in the infrared for companions to young stars, we can see thermal emission from planets that are still warm with the heat of their formation. Together with a UCLA team that

  7. Planets and Life

    Science.gov (United States)

    Sullivan, Woodruff T., III; Baross, John

    2007-09-01

    Foreword; Preface; Contributors; Prologue; Part I. History: 1. History of astrobiological ideas W. T. Sullivan and D. Carney; 2. From exobiology to astrobiology S. J. Dick; Part II. The Physical Stage: 3. Formation of Earth-like habitable planets D. E. Brownlee and M. Kress; 4. Planetary atmospheres and life D. Catling and J. F. Kasting; Part III. The Origin of Life on Earth: 5. Does 'life' have a definition? C.E. Cleland and C. F. Chyba; 6. Origin of life: crucial issues R. Shapiro; 7. Origin of proteins and nucleic acids A. Ricardo and S. A. Benner; 8. The roots of metabolism G.D. Cody and J. H. Scott; 9. Origin of cellular life D. W. Deamer; Part IV. Life on Earth: 10. Evolution: a defining feature of life J. A. Baross; 11. Evolution of metabolism and early microbial communities J. A. Leigh, D. A. Stahl and J. T. Staley; 12. The earliest records of life on Earth R. Buick; 13. The origin and diversification of eukaryotes M. L. Sogin, D. J. Patterson and A. McArthur; 14. Limits of carbon life on Earth and elsewhere J. A. Baross, J. Huber and M. Schrenk; 15. Life in ice J. W. Deming and H. Eicken; 16. The evolution and diversification of life S. Awramik and K. J. McNamara; 17. Mass extinctions P. D. Ward; Part V. Potentially Habitable Worlds: 18. Mars B. M. Jakosky, F. Westall and A. Brack; 19. Europa C. F. Chyba and C. B. Phillips; 20. Titan J. I. Lunine and B. Rizk; 21. Extrasolar planets P. Butler; Part VI. Searching for Extraterrestrial Life: 22. How to search for life on other worlds C. P. McKay; 23. Instruments and strategies for detecting extraterrestrial life P. G. Conrad; 24. Societial and ethical concerns M. S. Race; 25. Planetary protection J. D. Rummel; 26. Searching for extraterrestrial intelligence J. C. Tarter; 27. Alien biochemistries P. D. Ward and S. A. Benner; Part VII. Future of the Field: 28. Disciplinary and educational opportunities L. Wells, J. Armstrong and J. Huber; Epilogue C. F. Chyba; Appendixes: A. Units and usages; B. Planetary

  8. Detection of Extrasolar Planets by Transit Photometry

    Science.gov (United States)

    Borucki, William; Koch, David; Webster, Larry; Dunham, Edward; Witteborn, Fred; Jenkins, Jon; Caldwell, Douglas; Showen, Robert; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    technology exists to find such small planets, our group has conducted an end-to-end system test. The results of the laboratory tests are presented and show that we are ready to start the search for Earth-size planets.

  9. Four new planets around giant stars and the mass-metallicity correlation of planet-hosting stars

    CERN Document Server

    Jones, M I; Brahm, R; Wittenmyer, R A; Olivares, F E; Melo, C H F; Rojo, P; Jordán, A; Drass, H; Butler, R P; Wang, L

    2016-01-01

    CONTEXT. Exoplanet searches have demonstrated that giant planets are preferentially found around metal-rich stars and that their fraction increases with the stellar mass. AIMS. During the past six years, we have conducted a radial velocity follow-up program of 166 giant stars, to detect substellar companions, and characterizing their orbital properties. Using this information, we aim to study the role of the stellar evolution in the orbital parameters of the companions, and to unveil possible correlations between the stellar properties and the occurrence rate of giant planets. METHODS. Using FEROS and CHIRON spectra, we have computed precision radial velocities and we have derived atmospheric and physical parameters for all of our targets. Additionally, velocities computed from UCLES spectra are presented here. By studying the periodic radial velocity signals, we have detected the presence of several substellar companions. RESULTS. We present four new planetary systems around the giant stars HIP8541, HIP74890...

  10. Search Recipes

    Science.gov (United States)

    ... Tips A to Z Map Search Enter your search term 98 results • Advanced Search Everything News Videos e- ... usda.gov https://www.whatscooking.fns.usda.gov/search/solr-results/im_field_term_program/child-nutrition-cnp-163 We would like ...

  11. Can Investors Save The Planet?

    Institute of Scientific and Technical Information of China (English)

    MATTHEW PLOWRIGHT

    2008-01-01

    @@ The zoo people packed into a smart function room in Beijing's Kerry Center Hotel did not,at first glance,seem likely candidates to save the planet.The men were decked out in tailored suits and expensive leather shoes; the women wore clicking high heels and twirled designer handbags.Most were venture capitalists,or entrepreneurs searching for seed capital for their new start-ups.The conversation was all about IPOs and profitable exits.

  12. Expected Detection and False Alarm Rates for Transiting Jovian Planets

    CERN Document Server

    Brown, T M

    2003-01-01

    Ground-based searches for transiting Jupiter-sized planets have so far produced few detections of planets, but many of stellar systems with eclipse depths, durations, and orbital periods that resemble those expected from planets. I show that these detection rates are consistent with our present knowledge of binary and multiple-star systems, and of Jovian-mass extrasolar planets. Upcoming space-based searches for transiting Earth-sized planets will be largely unaffected by the sources of false alarms that afflict current ground-based searches, with one exception, namely distant eclipsing binaries whose light is strongly diluted by that of a foreground star. A byproduct of the rate estimation is evidence that the period distribution of extrasolar planets is depressed for periods between 5 and 200 days.

  13. On the Abundance of Circumbinary Planets

    CERN Document Server

    Armstrong, D J; Brown, D; Faedi, F; Chew, Y Gómez Maqueo; Martin, D; Pollacco, D; Udry, S

    2014-01-01

    Circumbinary planets have been the subject of much recent work, providing both simulations and new discoveries. We present the first observationally based determination of the rate of occurrence of these planets. This is derived from the publicly available Kepler data, using an automated search algorithm and debiasing process to produce occurrence rates implied by the seven systems already known. These rates depend critically on the planetary inclination distribution: if circumbinary planets are preferentially coplanar with their host binaries, as has been suggested, then the rate of occurrence of planets with $R_p>6R_\\oplus$ orbiting with $P_p}10R_\\oplus$) are significantly less common in circumbinary orbits than their smaller siblings, and confirm that the proposed shortfall of circumbinary planets orbiting the shorter period binaries in the Kepler sample is a real effect.

  14. The Efficiency of a Visual Skills Training Program on Visual Search Performance

    Directory of Open Access Journals (Sweden)

    Krzepota Justyna

    2015-06-01

    Full Text Available In this study, we conducted an experiment in which we analyzed the possibilities to develop visual skills by specifically targeted training of visual search. The aim of our study was to investigate whether, for how long and to what extent a training program for visual functions could improve visual search. The study involved 24 healthy students from the Szczecin University who were divided into two groups: experimental (12 and control (12. In addition to regular sports and recreational activities of the curriculum, the subjects of the experimental group also participated in 8-week long training with visual functions, 3 times a week for 45 min. The Signal Test of the Vienna Test System was performed four times: before entering the study, after first 4 weeks of the experiment, immediately after its completion and 4 weeks after the study terminated. The results of this experiment proved that an 8-week long perceptual training program significantly differentiated the plot of visual detecting time. For the visual detecting time changes, the first factor, Group, was significant as a main effect (F(1,22=6.49, p<0.05 as well as the second factor, Training (F(3,66=5.06, p<0.01. The interaction between the two factors (Group vs. Training of perceptual training was F(3,66=6.82 (p<0.001. Similarly, for the number of correct reactions, there was a main effect of a Group factor (F(1,22=23.40, p<0.001, a main effect of a Training factor (F(3,66=11.60, p<0.001 and a significant interaction between factors (Group vs. Training (F(3,66=10.33, p<0.001. Our study suggests that 8-week training of visual functions can improve visual search performance.

  15. The Efficiency of a Visual Skills Training Program on Visual Search Performance.

    Science.gov (United States)

    Krzepota, Justyna; Zwierko, Teresa; Puchalska-Niedbał, Lidia; Markiewicz, Mikołaj; Florkiewicz, Beata; Lubiński, Wojciech

    2015-06-27

    In this study, we conducted an experiment in which we analyzed the possibilities to develop visual skills by specifically targeted training of visual search. The aim of our study was to investigate whether, for how long and to what extent a training program for visual functions could improve visual search. The study involved 24 healthy students from the Szczecin University who were divided into two groups: experimental (12) and control (12). In addition to regular sports and recreational activities of the curriculum, the subjects of the experimental group also participated in 8-week long training with visual functions, 3 times a week for 45 min. The Signal Test of the Vienna Test System was performed four times: before entering the study, after first 4 weeks of the experiment, immediately after its completion and 4 weeks after the study terminated. The results of this experiment proved that an 8-week long perceptual training program significantly differentiated the plot of visual detecting time. For the visual detecting time changes, the first factor, Group, was significant as a main effect (F(1,22)=6.49, pperceptual training was F(3,66)=6.82 (p<0.001). Similarly, for the number of correct reactions, there was a main effect of a Group factor (F(1,22)=23.40, p<0.001), a main effect of a Training factor (F(3,66)=11.60, p<0.001) and a significant interaction between factors (Group vs. Training) (F(3,66)=10.33, p<0.001). Our study suggests that 8-week training of visual functions can improve visual search performance.

  16. A Planet Found by Pulsations

    Science.gov (United States)

    Kohler, Susanna

    2016-10-01

    Searching for planets around very hot stars is much more challenging than looking around cool stars. For this reason, the recent discovery of a planet around a main-sequence A star is an important find both because of its unique position near the stars habitable zone, and because of the way in which the planet was discovered.Challenges in VariabilityIn the past three decades, weve discovered thousands of exoplanets yet most of them have been found around cool stars (like M dwarfs) or moderate stars (like G stars like our Sun). Very few of the planets that weve found orbit hot stars; in fact, weve only discovered ~20 planets orbiting the very hot, main-sequence A stars.The instability strip, indicated on an H-R diagram. Stellar classification types are listed across the bottom of the diagram. Many main-sequence A stars reside in the instability strip. [Rursus]Why is this? We dont expect that main-sequence A stars host fewer planets than cooler stars. Instead, its primarily because the two main techniques that we use to find planets namely, transits and radial velocity cant be used as effectively on the main-sequence A stars that are most likely to host planets, because the luminosities of these stars are often variable.These stars can lie on whats known as the classical instability strip in the Herzsprung-Russell diagram. Such variable stars pulsate due to changes in the ionization state of atoms deep in their interiors, which causes the stars to puff up and then collapse back inward. For variable main-sequence A stars, the periods for these pulsations can be several to several tens of times per day.These very pulsations that make transits and radial-velocity measurements so difficult, however, can potentially be used to detect planets in a different way. Led by Simon Murphy (University of Sydney, Australia and Aarhus University, Denmark), a team of scientists has recently detected the first planet ever to be discovered around a main-sequence A star from the timing

  17. The Effects of an Inservice Program on School Administrators' Knowledge Concerning the Fourth Amendment's Applicability to Student Searches and Seizures.

    Science.gov (United States)

    Gonzalez, Orlando B.

    Findings of a study that examined the effect of a 13-week inservice program on administrators' awareness of laws governing student searches and seizures are presented in this practicum report. Four school-site administrators participated in the project once a week. Program activities included case analyses, role-playing exercises, and…

  18. Discovery of a warm, dusty giant planet around HIP 65426

    Science.gov (United States)

    Chauvin, G.; Desidera, S.; Lagrange, A.-M.; Vigan, A.; Gratton, R.; Langlois, M.; Bonnefoy, M.; Beuzit, J.-L.; Feldt, M.; Mouillet, D.; Meyer, M.; Cheetham, A.; Biller, B.; Boccaletti, A.; D'Orazi, V.; Galicher, R.; Hagelberg, J.; Maire, A.-L.; Mesa, D.; Olofsson, J.; Samland, M.; Schmidt, T. O. B.; Sissa, E.; Bonavita, M.; Charnay, B.; Cudel, M.; Daemgen, S.; Delorme, P.; Janin-Potiron, P.; Janson, M.; Keppler, M.; Le Coroller, H.; Ligi, R.; Marleau, G. D.; Messina, S.; Mollière, P.; Mordasini, C.; Müller, A.; Peretti, S.; Perrot, C.; Rodet, L.; Rouan, D.; Zurlo, A.; Dominik, C.; Henning, T.; Menard, F.; Schmid, H.-M.; Turatto, M.; Udry, S.; Vakili, F.; Abe, L.; Antichi, J.; Baruffolo, A.; Baudoz, P.; Baudrand, J.; Blanchard, P.; Bazzon, A.; Buey, T.; Carbillet, M.; Carle, M.; Charton, J.; Cascone, E.; Claudi, R.; Costille, A.; Deboulbe, A.; De Caprio, V.; Dohlen, K.; Fantinel, D.; Feautrier, P.; Fusco, T.; Gigan, P.; Giro, E.; Gisler, D.; Gluck, L.; Hubin, N.; Hugot, E.; Jaquet, M.; Kasper, M.; Madec, F.; Magnard, Y.; Martinez, P.; Maurel, D.; Le Mignant, D.; Möller-Nilsson, O.; Llored, M.; Moulin, T.; Origné, A.; Pavlov, A.; Perret, D.; Petit, C.; Pragt, J.; Puget, P.; Rabou, P.; Ramos, J.; Rigal, R.; Rochat, S.; Roelfsema, R.; Rousset, G.; Roux, A.; Salasnich, B.; Sauvage, J.-F.; Sevin, A.; Soenke, C.; Stadler, E.; Suarez, M.; Weber, L.; Wildi, F.; Antoniucci, S.; Augereau, J.-C.; Baudino, J.-L.; Brandner, W.; Engler, N.; Girard, J.; Gry, C.; Kral, Q.; Kopytova, T.; Lagadec, E.; Milli, J.; Moutou, C.; Schlieder, J.; Szulágyi, J.; Thalmann, C.; Wahhaj, Z.

    2017-09-01

    Aims: The SHINE program is a high-contrast near-infrared survey of 600 young, nearby stars aimed at searching for and characterizing new planetary systems using VLT/SPHERE's unprecedented high-contrast and high-angular-resolution imaging capabilities. It is also intended to place statistical constraints on the rate, mass and orbital distributions of the giant planet population at large orbits as a function of the stellar host mass and age to test planet-formation theories. Methods: We used the IRDIS dual-band imager and the IFS integral field spectrograph of SPHERE to acquire high-contrast coronagraphic differential near-infrared images and spectra of the young A2 star HIP 65426. It is a member of the 17 Myr old Lower Centaurus-Crux association. Results: At a separation of 830 mas (92 au projected) from the star, we detect a faint red companion. Multi-epoch observations confirm that it shares common proper motion with HIP 65426. Spectro-photometric measurements extracted with IFS and IRDIS between 0.95 and 2.2 μm indicate a warm, dusty atmosphere characteristic of young low-surface-gravity L5-L7 dwarfs. Hot-start evolutionary models predict a luminosity consistent with a 6-12 MJup, Teff = 1300-1600 K and R = 1.5 ± 0.1 RJup giant planet. Finally, the comparison with Exo-REM and PHOENIX BT-Settl synthetic atmosphere models gives consistent effective temperatures but with slightly higher surface gravity solutions of log (g) = 4.0-5.0 with smaller radii (1.0-1.3 RJup). Conclusions: Given its physical and spectral properties, HIP 65426 b occupies a rather unique placement in terms of age, mass, and spectral-type among the currently known imaged planets. It represents a particularly interesting case to study the presence of clouds as a function of particle size, composition, and location in the atmosphere, to search for signatures of non-equilibrium chemistry, and finally to test the theory of planet formation and evolution. Based on observations collected at La Silla

  19. Searching for Gas Giant Planets on Solar System Scales: VLT NACO/APP Observations of the Debris Disk Host Stars HD172555 and HD115892

    CERN Document Server

    Quanz, Sascha P; Meyer, Michael R; Girard, Julien H V; Kasper, Markus

    2011-01-01

    Using the APP coronagraph of VLT/NACO we searched for planetary mass companions around HD115892 and HD172555 in the thermal infrared at 4 micron. Both objects harbor unusually luminous debris disks for their age and it has been suggested that small dust grains were produced recently in transient events (e.g., a collision) in these systems. Such a collision of planetesimals or protoplanets could have been dynamically triggered by yet unseen companions. We did not detect any companions in our images but derived the following detection limits: For both objects we would have detected companions with apparent magnitudes between ~13.2-14.1 mag at angular separations between 0.4- 1.0" at the 5-sigma level. For HD115892 we were sensitive to companions with 12.1 mag even at 0.3". Using theoretical models these magnitudes are converted into mass limits. For HD115892 we would have detected objects with 10-15 M_Jup at angular separations between 0.4-1.0" (7-18 AU). At 0.3" (~5.5 AU) the detection limit was ~25 M_Jup. For...

  20. The SOPHIE search for northern extrasolar planets VIII. Follow-up of ELODIE candidates: long-period brown-dwarf companions

    CERN Document Server

    Bouchy, F; Díaz, R F; Forveille, T; Boisse, I; Arnold, L; Astudillo-Defru, N; Beuzit, J -L; Bonfils, X; Borgniet, S; Bourrier, V; Courcol, B; Delfosse, X; Demangeon, O; Delorme, P; Ehrenreich, D; Hébrard, G; Lagrange, A -M; Mayor, M; Montagnier, G; Moutou, C; Naef, D; Pepe, F; Perrier, C; Queloz, D; Rey, J; Sahlmann, J; Santerne, A; Santos, N C; Sivan, J -P; Udry, S; Wilson, P A

    2015-01-01

    Long-period brown dwarf companions detected in radial velocity surveys are important targets for direct imaging and astrometry to calibrate the mass-luminosity relation of substellar objects. Through a 20-year radial velocity monitoring of solar-type stars that began with ELODIE and was extended with SOPHIE spectrographs, giant exoplanets and brown dwarfs with orbital periods longer than ten years are discovered. We report the detection of five new potential brown dwarfs with minimum masses between 32 and 83 Jupiter mass orbiting solar-type stars with periods longer than ten years. An upper mass limit of these companions is provided using astrometric Hipparcos data, high-angular resolution imaging made with PUEO, and a deep analysis of the cross-correlation function of the main stellar spectra to search for blend effects or faint secondary components. These objects double the number of known brown dwarf companions with orbital periods longer than ten years and reinforce the conclusion that the occurrence of s...

  1. Volatiles and refratories in solar analogs: no terrestial planet connection

    OpenAIRE

    Hernandez, J. I. Gonzalez; Israelian, G.; Santos,N.C.; Sousa, S.; Delgado-Mena, E.; Neves, V.; Udry, S.

    2010-01-01

    We have analysed very high-quality HARPS and UVES spectra of 95 solar analogs, 24 hosting planets and 71 without detected planets, to search for any possible signature of terrestial planets in the chemical abundances of volatile and refractory elements with respect to the solar abundances. We demonstrate that stars with and without planets in this sample show similar mean abundance ratios, in particular, a sub-sample of 14 planet-host and 14 "single" solar analogs in the metallicity range 0.14

  2. THE GEMINI PLANET-FINDING CAMPAIGN: THE FREQUENCY OF GIANT PLANETS AROUND DEBRIS DISK STARS

    Energy Technology Data Exchange (ETDEWEB)

    Wahhaj, Zahed [European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago (Chile); Liu, Michael C.; Nielsen, Eric L.; Ftaclas, Christ; Chun, Mark [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Biller, Beth A. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Hayward, Thomas L. [Gemini Observatory, Southern Operations Center, c/o AURA, Casilla 603, La Serena (Chile); Close, Laird M.; Males, Jared R.; Skemer, Andrew [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Thatte, Niranjan; Tecza, Matthias [Department of Astronomy, University of Oxford, DWB, Keble Road, Oxford OX1 3RH (United Kingdom); Shkolnik, Evgenya L. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Kuchner, Marc [NASA Goddard Space Flight Center, Exoplanets and Stellar Astrophysics Laboratory, Greenbelt, MD 20771 (United States); Reid, I. Neill [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); De Gouveia Dal Pino, Elisabete M.; Gregorio-Hetem, Jane [Departamento de Astronomia, Universidade de Sao Paulo, IAG/USP, Rua do Matao 1226, 05508-900 Sao Paulo, SP (Brazil); Alencar, Silvia H. P. [Departamento de Fisica-ICEx-UFMG, Av. Antonio Carlos 6627, 30270-901 Belo Horizonte, MG (Brazil); Boss, Alan [Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015 (United States); Lin, Douglas N. C. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA (United States); and others

    2013-08-20

    We have completed a high-contrast direct imaging survey for giant planets around 57 debris disk stars as part of the Gemini NICI Planet-Finding Campaign. We achieved median H-band contrasts of 12.4 mag at 0.''5 and 14.1 mag at 1'' separation. Follow-up observations of the 66 candidates with projected separation <500 AU show that all of them are background objects. To establish statistical constraints on the underlying giant planet population based on our imaging data, we have developed a new Bayesian formalism that incorporates (1) non-detections, (2) single-epoch candidates, (3) astrometric and (4) photometric information, and (5) the possibility of multiple planets per star to constrain the planet population. Our formalism allows us to include in our analysis the previously known {beta} Pictoris and the HR 8799 planets. Our results show at 95% confidence that <13% of debris disk stars have a {>=}5 M{sub Jup} planet beyond 80 AU, and <21% of debris disk stars have a {>=}3 M{sub Jup} planet outside of 40 AU, based on hot-start evolutionary models. We model the population of directly imaged planets as d {sup 2} N/dMda{proportional_to}m {sup {alpha}} a {sup {beta}}, where m is planet mass and a is orbital semi-major axis (with a maximum value of a{sub max}). We find that {beta} < -0.8 and/or {alpha} > 1.7. Likewise, we find that {beta} < -0.8 and/or a{sub max} < 200 AU. For the case where the planet frequency rises sharply with mass ({alpha} > 1.7), this occurs because all the planets detected to date have masses above 5 M{sub Jup}, but planets of lower mass could easily have been detected by our search. If we ignore the {beta} Pic and HR 8799 planets (should they belong to a rare and distinct group), we find that <20% of debris disk stars have a {>=}3 M{sub Jup} planet beyond 10 AU, and {beta} < -0.8 and/or {alpha} < -1.5. Likewise, {beta} < -0.8 and/or a{sub max} < 125 AU. Our Bayesian constraints are not strong enough to reveal any dependence

  3. Optical techniques for the detection of extrasolar planets - A critical review

    Science.gov (United States)

    Matloff, G. L.; Fennelly, A. J.

    1976-01-01

    Proposed optical techniques of extrasolar planet detection are discussed and compared. These include terrestrial, orbital, and moon-based systems. Terrestrial systems include ground-level searches for random eclipses of primaries and 'light' echoes of stellar flares from companion planets as well as balloon-mounted telescopes operating in the stratosphere used in conjunction with orbital occulters. Space telescopes considered are multimirror systems simulating huge mirror diameters and single-mirror telescopes, such as the 3-meter Large Space Telescope, used in conjunction with occulters. Although very modest systems are capable of detecting extrasolar planets, the amount of information we can gather regarding these worlds is a function of system complexity and program duration.

  4. China's Reconfigurable Planet Probing Robot

    Institute of Scientific and Technical Information of China (English)

    RenShufang

    2005-01-01

    Research of reconfigurable planet probing robot conducted by the Shenyang Institute of Automation of the Chinese Academy of Science (SIA-CAS) has passed appraisal of 863 Program sresearch on intelligent robots.

  5. Can CMB Experiments Find Planet Nine?

    Science.gov (United States)

    Kohler, Susanna

    2016-04-01

    Recent studies have identified signs of an unseen, distant ninth planet in our solar system. How might we find the elusive Planet Nine? A team of scientists suggests the key might be cosmology experiments.AHypothetical PlanetOrbits of six distant Kuiper-belt objects. Their clustered perihelia and orbital orientations suggest they may have been shepherded by a massive object, hypothesized to be Planet Nine. [Caltech/Robert Hurt]Early this year, a study was published that demonstrated that the clustered orbits of distant Kuiper belt objects (and several other features of our solar system) can be explained by the gravitational tug of a yet-undiscovered planet. This hypothetical Planet Nine is predicted to be a giant planet similar to Neptune or Uranus, with a mass of more than ~10 Earthmasses, currently orbiting ~700 AU away.In a recent study, a team of scientists led by Nicolas Cowan (McGill University in Canada) has estimated the blackbody emission expected from Planet Nine. The team proposes how we might be able to search for this distant body using its heat signature.Heat from an Icy WorldCowan and collaborators first estimate Planet Nines effective temperature, based on the solar flux received at ~700 AU and assuming its internal heating is similar to Uranus or Neptune. They find that Planet Nines effective temperature would likely be an icy ~3050 K, corresponding to a blackbody peak at 50100 micrometers.Search space for Planet Nine. Based on its millimeter flux and annual parallax motion, several current and future cosmology experiments may be able to detect it. Experiments resolution ranges are shown with blue boxes. [Cowan et al. 2016]How can we detect an object withemission that peaks in this range? Intriguingly, cosmology experiments monitoring the cosmic microwave background (CMB) radiation are optimized for millimeter flux. At a wavelength of 1mm, Cowan and collaborators estimate that Planet Nine would have a very detectable flux level of ~30 mJy. The

  6. Semantic Search-Based Genetic Programming and the Effect of Intron Deletion.

    Science.gov (United States)

    Castelli, Mauro; Vanneschi, Leonardo; Silva, Sara

    2014-01-01

    The concept of semantics (in the sense of input-output behavior of solutions on training data) has been the subject of a noteworthy interest in the genetic programming (GP) research community over the past few years. In this paper, we present a new GP system that uses the concept of semantics to improve search effectiveness. It maintains a distribution of different semantic behaviors and biases the search toward solutions that have similar semantics to the best solutions that have been found so far. We present experimental evidence of the fact that the new semantics-based GP system outperforms the standard GP and the well-known bacterial GP on a set of test functions, showing particularly interesting results for noncontinuous (i.e., generally harder to optimize) test functions. We also observe that the solutions generated by the proposed GP system often have a larger size than the ones returned by standard GP and bacterial GP and contain an elevated number of introns, i.e., parts of code that do not have any effect on the semantics. Nevertheless, we show that the deletion of introns during the evolution does not affect the performance of the proposed method.

  7. A depth-first search algorithm to compute elementary flux modes by linear programming.

    Science.gov (United States)

    Quek, Lake-Ee; Nielsen, Lars K

    2014-07-30

    The decomposition of complex metabolic networks into elementary flux modes (EFMs) provides a useful framework for exploring reaction interactions systematically. Generating a complete set of EFMs for large-scale models, however, is near impossible. Even for moderately-sized models (depth-first search algorithm using linear programming (LP) to enumerate EFMs in an exhaustive fashion. Constraints can be introduced to directly generate a subset of EFMs satisfying the set of constraints. The depth-first search algorithm has a constant memory overhead. Using flux constraints, a large LP problem can be massively divided and parallelized into independent sub-jobs for deployment into computing clusters. Since the sub-jobs do not overlap, the approach scales to utilize all available computing nodes with minimal coordination overhead or memory limitations. The speed of the algorithm was comparable to efmtool, a mainstream Double Description method, when enumerating all EFMs; the attrition power gained from performing flux feasibility tests offsets the increased computational demand of running an LP solver. Unlike the Double Description method, the algorithm enables accelerated enumeration of all EFMs satisfying a set of constraints.

  8. Terrestrial Planet Finder: science overview

    Science.gov (United States)

    Unwin, Stephen C.; Beichman, C. A.

    2004-01-01

    The Terrestrial Planet Finder (TPF) seeks to revolutionize our understanding of humanity's place in the universe - by searching for Earth-like planets using reflected light, or thermal emission in the mid-infrared. Direct detection implies that TPF must separate planet light from glare of the nearby star, a technical challenge which has only in recent years been recognized as surmountable. TPF will obtain a low-resolution spectra of each planets it detects, providing some of its basic physical characteristics and its main atmospheric constituents, thereby allowing us to assess the likelihood that habitable conditions exist there. NASA has decided the scientific importance of this research is so high that TPF will be pursued as two complementary space observatories: a visible-light coronagraph and a mid-infrared formation flying interferometer. The combination of spectra from both wavebands is much more valuable than either taken separately, and it will allow a much fuller understanding of the wide diversity of planetary atmospheres that may be expected to exist. Measurements across a broad wavelength range will yield not only physical properties such as size and albedo, but will also serve as the foundations of a reliable and robust assessment of habitability and the presence of life.

  9. Comparing Evolutionary Programs and Evolutionary Pattern Search Algorithms: A Drug Docking Application

    Energy Technology Data Exchange (ETDEWEB)

    Hart, W.E.

    1999-02-10

    Evolutionary programs (EPs) and evolutionary pattern search algorithms (EPSAS) are two general classes of evolutionary methods for optimizing on continuous domains. The relative performance of these methods has been evaluated on standard global optimization test functions, and these results suggest that EPSAs more robustly converge to near-optimal solutions than EPs. In this paper we evaluate the relative performance of EPSAs and EPs on a real-world application: flexible ligand binding in the Autodock docking software. We compare the performance of these methods on a suite of docking test problems. Our results confirm that EPSAs and EPs have comparable performance, and they suggest that EPSAs may be more robust on larger, more complex problems.

  10. Integer programming formulation and variable neighborhood search metaheuristic for the multiproduct pipeline scheduling problem

    Energy Technology Data Exchange (ETDEWEB)

    Souza Filho, Erito M.; Bahiense, Laura; Ferreira Filho, Virgilio J.M. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE); Lima, Leonardo [Centro Federal de Educacao Tecnologica Celso Sukow da Fonseca (CEFET-RJ), Rio de Janeiro, RJ (Brazil)

    2008-07-01

    Pipeline are known as the most reliable and economical mode of transportation for petroleum and its derivatives, especially when large amounts of products have to be pumped for large distances. In this work we address the short-term schedule of a pipeline system comprising the distribution of several petroleum derivatives from a single oil refinery to several depots, connected to local consumer markets, through a single multi-product pipeline. We propose an integer linear programming formulation and a variable neighborhood search meta-heuristic in order to compare the performances of the exact and heuristic approaches to the problem. Computational tests in C language and MOSEL/XPRESS-MP language are performed over a real Brazilian pipeline system. (author)

  11. SEARCH: Study of Environmental Arctic Change—A System-scale, Cross-disciplinary Arctic Research Program

    Science.gov (United States)

    Wiggins, H. V.; Eicken, H.; Fox, S. E.; Search Science Steering Committee

    2010-12-01

    The Study of Environmental Arctic Change (SEARCH) is a multi-agency effort to understand system-scale arctic change. Interrelated environmental changes in the Arctic are affecting ecosystems and living resources and are impacting local and global communities. The SEARCH program is guided by the Science Steering Committee (SSC), the Interagency Program Management Committee (IPMC), and focused panels. Over 150 projects and activities contribute to SEARCH implementation. The Observing Change component is underway through the National Science Foundation’s (NSF) Arctic Observing Network (AON), NOAA-sponsored atmospheric and sea ice observations, and other relevant national and international efforts. The Understanding Change component of SEARCH consists of modeling and analysis efforts, with strong linkages to relevant programs such as NSF’s Arctic System Science (ARCSS) Program. The SEARCH Sea Ice Outlook (http://www.arcus.org/search/seaiceoutlook/index.php) is an "Understanding Change" synthesis effort that aims to advance our understanding of the arctic sea ice system. The Responding to Change element currently includes initial planning efforts by the International Study of Arctic Change (ISAC) program as well as a newly-launched "Sea Ice for Walrus Outlook," which is a weekly report of sea ice conditions geared to Alaska Native walrus subsistence hunters, coastal communities, and others interested in sea ice and walrus (http://www.arcus.org/search/siwo). SEARCH is sponsored by eight U.S. agencies, including: the National Science Foundation (NSF), the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), the Department of Defense (DOD), the Department of Energy (DOE), the Department of the Interior (DOI), the Smithsonian Institution, and the U.S. Department of Agriculture (USDA). The U.S. Arctic Research Commission participates as an IPMC observer. For further information, please visit the website: http://www.arcus.org/search

  12. Creatures on Other Planets

    Institute of Scientific and Technical Information of China (English)

    罗汉中; 张静

    2000-01-01

    People often discuss whether there are creatures on other planets .Some people say “yes” while others say “no” This is because they haven't seen any real creatures or flying objects from other planets.

  13. Planets transiting non-eclipsing binaries

    Science.gov (United States)

    Martin, David V.; Triaud, Amaury H. M. J.

    2014-10-01

    The majority of binary stars do not eclipse. Current searches for transiting circumbinary planets concentrate on eclipsing binaries, and are therefore restricted to a small fraction of potential hosts. We investigate the concept of finding planets transiting non-eclipsing binaries, whose geometry would require mutually inclined planes. Using an N-body code we explore how the number and sequence of transits vary as functions of observing time and orbital parameters. The concept is then generalised thanks to a suite of simulated circumbinary systems. Binaries are constructed from radial-velocity surveys of the solar neighbourhood. They are then populated with orbiting gas giants, drawn from a range of distributions. The binary population is shown to be compatible with the Kepler eclipsing binary catalogue, indicating that the properties of binaries may be as universal as the initial mass function. These synthetic systems produce transiting circumbinary planets occurring on both eclipsing and non-eclipsing binaries. Simulated planets transiting eclipsing binaries are compared with published Kepler detections. We find 1) that planets transiting non-eclipsing binaries are probably present in the Kepler data; 2) that observational biases alone cannot account for the observed over-density of circumbinary planets near the stability limit, which implies a physical pile-up; and 3) that the distributions of gas giants orbiting single and binary stars are likely different. Estimating the frequency of circumbinary planets is degenerate with the spread in mutual inclination. Only a minimum occurrence rate can be produced, which we find to be compatible with 9%. Searching for inclined circumbinary planets may significantly increase the population of known objects and will test our conclusions. Their presence, or absence, will reveal the true occurrence rate and help develop circumbinary planet formation theories.

  14. Barnard’s Star: Planets or Pretense

    Science.gov (United States)

    Bartlett, Jennifer L.; Ianna, P. A.

    2014-01-01

    Barnard’s Star remains popular with planet hunters because it is not only an extremely near, high proper motion star, but also the object of early planet-detection claims. In 1963, van de Kamp explained perturbations in its proper motion by the presence of a planet. In 1969, he produced another single-planet solution and a two-planet solution to the astrometric wobbles detected. At least 19 studies have failed to confirm his results using a range of techniques, including radial velocity, direct imaging, and speckle interferometry. However, most of them lacked the sensitivity to detect the planets he described, including astrometric studies at the McCormick and Naval Observatories. However, radial-velocity monitoring of Barnard’s Star at Lick and Keck Observatories from 1987 through 2012 appears to have ruled out such planets. Based upon observations made at the Sproul Observatory between 1916 and 1962, van de Kamp claimed that Barnard’s Star had a planet with about 1.6 times the mass of Jupiter and an orbital period of 24 years. After accounting for instrumentation effects that might have been partially responsible for his initial results, he continued to assert that this red dwarf had two planets. In his 1982 analysis of ~20,000 exposures collected between 1938 and 1981, he calculated that two planets with 0.7- and 0.5-Jupiter masses in 12- and 20-year orbits, respectively, orbited the second-closest stellar system to our own. Starting in 1995, the dramatic successes of radial velocity searches for extrasolar planets drove van de Kamp’s unsubstantiated claims from popular consciousness. Although many low-mass stellar companions were discovered through astrometry, the technique has been less successful for planets: “The Extrasolar Planets Encyclopaedia” identifies one such discovery out of the 997 planets listed on 2013 September 23. Although Barnard’s Star has lost its pretensions to hosting the first extrasolar planets known, its intrinsic

  15. Naming the extrasolar planets

    CERN Document Server

    Lyra, W

    2009-01-01

    Extrasolar planets are not named and are referred to only by their assigned scientific designation. The reason given by the IAU to not name the planets is that it is considered impractical as planets are expected to be common. I advance some reasons as to why this logic is flawed, and suggest names for the 403 extrasolar planet candidates known as of Oct 2009, based on the continued tradition of names from Roman-Greek mythology.

  16. PLANET HUNTERS: ASSESSING THE KEPLER INVENTORY OF SHORT-PERIOD PLANETS

    Energy Technology Data Exchange (ETDEWEB)

    Schwamb, Megan E. [Yale Center for Astronomy and Astrophysics, Yale University, P.O. Box 208121, New Haven, CT 06520 (United States); Lintott, Chris J.; Lynn, Stuart; Smith, Arfon M.; Simpson, Robert J. [Oxford Astrophysics, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Fischer, Debra A.; Giguere, Matthew J.; Brewer, John M. [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Parrish, Michael [Adler Planetarium, 1300 S. Lake Shore Drive, Chicago, IL 60605 (United States); Schawinski, Kevin, E-mail: megan.schwamb@yale.edu [Department of Physics, Yale University, New Haven, CT 06511 (United States)

    2012-08-01

    We present the results from a search of data from the first 33.5 days of the Kepler science mission (Quarter 1) for exoplanet transits by the Planet Hunters citizen science project. Planet Hunters enlists members of the general public to visually identify transits in the publicly released Kepler light curves via the World Wide Web. Over 24,000 volunteers reviewed the Kepler Quarter 1 data set. We examine the abundance of {>=}2 R{sub Circled-Plus} planets on short-period (<15 days) orbits based on Planet Hunters detections. We present these results along with an analysis of the detection efficiency of human classifiers to identify planetary transits including a comparison to the Kepler inventory of planet candidates. Although performance drops rapidly for smaller radii, {>=}4 R{sub Circled-Plus} Planet Hunters {>=}85% efficient at identifying transit signals for planets with periods less than 15 days for the Kepler sample of target stars. Our high efficiency rate for simulated transits along with recovery of the majority of Kepler {>=}4 R{sub Circled-Plus} planets suggests that the Kepler inventory of {>=}4 R{sub Circled-Plus} short-period planets is nearly complete.

  17. The effect of planet-planet scattering on the survival of exomoons

    CERN Document Server

    Gong, Yan-Xiang; Xie, Ji-Wei; Wu, Xiao-Mei; 10.1088/2041-8205/769/1/L14

    2013-01-01

    Compared to the giant planets in the solar system, exoplanets have many remarkable properties such as the prevalence of giant planets on eccentric orbits and the presence of hot Jupiters. Planet-planet scattering (PPS) between giant planets is a possible mechanism in interpreting above and other observed properties. If the observed giant planet architectures are indeed the outcomes of PPS, such drastic dynamical process must affect their primordial moon systems. In this Letter, we discuss the effect of the PPS on the survival of their regular moons. From the viewpoint of observations, some preliminary conclusions are drawn from the simulations. 1. PPS is a destructive process to the moon systems, single planets on eccentric orbits are not the ideal moon-search targets. 2. If hot Jupiters formed through PPS, their original moons have little chance to survive. 3. Planets in multiple systems with small eccentricities are more likely holding their primordial moons. 4. Compared to the lower-mass planets, the massi...

  18. Kepler Planet Formation

    Science.gov (United States)

    Lissauer, Jack J.

    2015-01-01

    Kepler has vastly increased our knowledge of planets and planetary systems located close to stars. The new data shows surprising results for planetary abundances, planetary spacings and the distribution of planets on a mass-radius diagram. The implications of these results for theories of planet formation will be discussed.

  19. The NASA-UC Eta-Earth Program: III. A Super-Earth orbiting HD 97658 and a Neptune-mass planet orbiting Gl 785

    CERN Document Server

    Howard, Andrew W; Marcy, Geoffrey W; Fischer, Debra A; Wright, Jason T; Henry, Gregory W; Isaacson, Howard; Valenti, Jeff A; Anderson, Jay; Piskunov, Nikolai E

    2010-01-01

    We report the discovery of planets orbiting two bright, nearby early K dwarf stars, HD 97658 and Gl 785. These planets were detected by Keplerian modelling of radial velocities measured with Keck-HIRES for the NASA-UC Eta-Earth Survey. HD 97658 b is a close-in super-Earth with minimum mass Msini = 8.2 +/- 1.2 M_Earth, orbital period P = 9.494 +/- 0.005 d, and an orbit that is consistent with circular. Gl 785 b is a Neptune-mass planet with Msini = 21.6 +/- 2.0 M_Earth, P = 74.39 +/- 0.12 d, and orbital eccentricity 0.30 +/- 0.09. Photometric observations with the T12 0.8 m automatic photometric telescope at Fairborn Observatory show that HD 97658 is photometrically constant at the radial velocity period to 0.09 mmag, supporting the existence of the planet.

  20. Can Skateboarding Save the Planet? A Curricular Unit on Global Climate Change Developed Through the NASA LIFT-OFF Program

    Science.gov (United States)

    Pruett, L. E.; Burrell, S.; Chidester, C.; Metzger, E. P.

    2010-12-01

    The inclusion of global climate change education in California public high schools is constrained by several factors, including the planning time needed to effectively correlate state content standards to the multidisciplinary science of climate change, the lack of time in the curriculum, and budget constraints that limit resources for teachers. Recent efforts by the NASA LIFT-OFF program to support classroom teachers in the development of inquiry-based curricular materials have helped to alleviate many of these burdens. NASA LIFT-OFF is funded by a grant to the Alameda County Office of Education and involves a partnership between the Alameda, Santa Clara, and Los Angeles county offices of education and science faculty at California State University (CSU) East Bay, San Jose State University (SJSU), and Cal Poly Pomona. LIFT-OFF goals are to improve high school science teachers’ content knowledge through interactions with scientists from the CSU campuses, NASA, and the SETI Institute and to enhance their ability to plan and implement high-quality science inquiry in their classrooms. LIFT-OFF teachers at the three CSU campuses are developing instructional cases that use NASA resources and research-based pedagogical practices to explore engaging real-world questions. We participated in SJSU’s 2010 LIFT-OFF summer institute and worked as a team to develop a 12-day unit for high school students that focuses on the science behind global climate change. In addition to delivering science content, the unit engages students in critical thinking and evaluation. Students generate, access and interpret data, and use the knowledge gained to make small lifestyle changes that aid in the reduction of their greenhouse gas emissions. Not only does this unit of study empower students to make science-based decisions, it also incorporates diverse learning strategies, such as the use of visuals aids, language acquisition techniques to improve literacy, formative assessments and daily

  1. The VLT/NaCo large program to probe the occurrence of exoplanets and brown dwarfs at wide orbits. III. The frequency of brown dwarfs and giant planets as companions to solar-type stars

    CERN Document Server

    Reggiani, M; Chauvin, G; Vigan, A; Quanz, S P; Biller, B; Bonavita, M; Desidera, S; Delorme, P; Hagelberg, J; Maire, A -L; Boccaletti, A; Beuzit, J -L; Buenzli, E; Carson, J; Covino, E; Feldt, M; Girard, J; Gratton, R; Henning, T; Kasper, M; Lagrange, A -M; Mesa, D; Messina, S; Montagnier, G; Mordasini, C; Mouillet, D; Schlieder, J E; Segransan, D; Thalmann, C; Zurlo, A

    2015-01-01

    In recent years there have been many attempts to characterize the occurrence of stellar, BD and planetary-mass companions to solar-type stars, with the aim of constraining formation mechanisms. From RV observations a dearth of companions with masses between 10-40 MJup has been noticed at close separations, suggesting the possibility of a distinct formation mechanism for objects above and below this range. We present a model for the substellar companion mass function (CMF). It consists of the superposition of the planet and BD companion mass distributions, assuming that we can extrapolate the RV measured companion mass function for planets to larger separations and the stellar companion mass-ratio distribution over all separations into the BD mass regime. By using both the results of the VLT/NaCo large program and the complementary archive datasets that probe the occurrence of planets and BDs on wide orbits around solar-type stars, we place some constraints on the planet and BD distributions. We developed a MC...

  2. Extrasolar planets: constraints for planet formation models.

    Science.gov (United States)

    Santos, Nuno C; Benz, Willy; Mayor, Michel

    2005-10-14

    Since 1995, more than 150 extrasolar planets have been discovered, most of them in orbits quite different from those of the giant planets in our own solar system. The number of discovered extrasolar planets demonstrates that planetary systems are common but also that they may possess a large variety of properties. As the number of detections grows, statistical studies of the properties of exoplanets and their host stars can be conducted to unravel some of the key physical and chemical processes leading to the formation of planetary systems.

  3. Direct Imaging of Extra-Solar Planets – Homogeneous Comparison of Detected Planets and Candidates

    OpenAIRE

    Neuhäuser, Ralph; Schmidt, Tobias

    2012-01-01

    Searching the literature, we found 25 stars with directly imaged planets and candidates. We gathered photometric and spectral information for all these objects to derive their luminosities in a homogeneous way, taking a bolometric correction into account. Using theoretical evolutionary models, one can then estimate the mass from luminosity, temperature, and age. According to our mass estimates, all of them can have a mass below 25 Jup masses, so that they are considered as planets.

  4. Origins Space Telescope: Planet-forming disks and exoplanets

    Science.gov (United States)

    Pontoppidan, Klaus; Origins Space Telescope Study Team

    2017-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its imagers and spectrographs will enable a variety of surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu. This presentation will provide a summary of the science case related to planet formation and exoplanets. Leveraging orders of magnitude of improvements in sensitivity, the Origins Telescope will reveal the path of water from the interstellar medium to the inner regions of planet-forming disks, and determine the total masses of disks around stars across the stellar mass range out to distances of 500 pc. It will measure the temperatures and search for basic chemical ingredients for life on rocky planets. Beyond this, the Origins Telescope will open a vast discovery space in the general areas of star formation, protoplanetary and debris disks, and cool exoplanets in habitable zones.

  5. Humans Need Not Apply: Robotization of Kepler Planet Candidate Vetting

    Science.gov (United States)

    Coughlin, Jeffrey; Mullally, Fergal; Thompson, Susan E.; Kepler Team

    2015-01-01

    Until now, the vast majority of Kepler planet candidate vetting has been performed by a dedicated team of humans. While human expertise has been invaluable in understanding the nuances of Kepler data, human vetting is very time-consuming and can be inconsistent. Over 20,000 threshold crossing events have been produced by the latest pipeline run on all 17 quarters of Kepler mission data, and many more artificial planet transits have been injected to estimate completeness. Given these large numbers, human vetting is no longer feasible on a reasonable time-scale, and would be difficult to characterize. We have created automated vetting programs known as "robovetters" that are specifically designed to mimic the decision-making process employed by the humans. They analyze both the light curve and pixel-level data in order to produce specific reasons for identifying false positives. We present benchmark tests on the Q1-Q16 Kepler planet catalog, which was vetted by humans, and present preliminary robovetter results based on a recent transit-search of the newly reprocessed Q1-Q17 data set.

  6. Stars and Planets: A New Set of Middle School Activities

    Science.gov (United States)

    Urquhart, M. L.

    2002-01-01

    A set of lesson plans for grades 6-8 which deal with the sizes and distances of stars and planets using a scale factor of 1 to 10 billion, the life cycle of stars, and the search for planets beyond the solar system. Additional information is contained in the original extended abstract.

  7. Two Jupiter-Mass Planets Orbiting HD 154672 and HD 205739

    CERN Document Server

    Lopez-Morales, Mercedes; Fischer, Debra A; Minniti, Dante; Shectman, Stephen A; Takeda, Genya; Adams, Fred C; Wright, Jason T; Arriagada, Pamela

    2008-01-01

    We report the detection of the first two planets from the N2K Doppler planet search program at the Magellan telescopes. The first planet has a mass of M sin i = 4.96 M_Jup and is orbiting the G3 IV star HD154672 with an orbital period of 163.9 days. The second planet is orbiting the F7 V star HD205739 with an orbital period of 279.8 days and has a mass of M sin i = 1.37 M_Jup. Both planets are in eccentric orbits, with eccentricities e = 0.61 and e = 0.27, respectively. Both stars are metal rich and appear to be chromospherically inactive, based on inspection of their Ca II H and K lines. Finally, the best Keplerian model fit to HD205739b shows a trend of 0.0649 m/s/day, suggesting the presence of an additional outer body in that system.

  8. STRATEGIES IN SEARCHING HOMOGENEITY IN A FACULTY OF A POSTGRADUATE PROGRAM.

    Science.gov (United States)

    Cecatti, José G; Fernandes, Karayna G; Souza, Renato T; Silveira, Carla; Surita, Fernanda G

    2015-01-01

    The professor plays a fundamental role in a graduate program, considering he/she is who plans and performs a great part of the tasks, and he/she is also responsible for spreading knowledge among students. The professor should use didactical resources for his/her continuous qualification, being responsible for situations favoring the development of students who should learn according to the best and easier way. The homogeneity in the postgraduate program consists of having subgroups of research corresponding to the Areas of Concentration, where each subgroup works with some distinct topics of research. It is desirable that the staff of postgraduate program has a significant and high quality scientific production, homogeneously distributed among them. The professors must systematically search for resources for research in agencies supporting research, not only for sponsoring the studies, but also for adding value to the researchers involved in the whole activities. The postgraduate programs need to support the professional qualification of their staff who should improve their knowledge on epidemiology for clinical studies, ethics in research and teaching skills. Two characteristics of the postgraduate system in Brazil are the nucleation and solidarity, based on the capacity and/or interest of those more structured programs to help those beginners, cooperating with their activities. The Capes (the national governmental agency responsible for coordinating and evaluating all postgraduate programs in Brazil) valorizes the social insertion in the context of postgraduate programs´ activities. It includes the recognition of activities with technological, cultural, educational and social impact as criteria for evaluation of the programs. Does exist an ideal model of postgraduate program? We think that there is no a mathematical formulae nor an ideal model for a postgraduate program. Each institution should make adaptations and search for improvements of their faculty and

  9. Does the Galactic Bulge Have Fewer Planets?

    Science.gov (United States)

    Kohler, Susanna

    2016-12-01

    The Milky Ways dense central bulge is a very different environment than the surrounding galactic disk in which we live. Do the differences affect the ability of planets to form in the bulge?Exploring Galactic PlanetsSchematic illustrating how gravitational microlensing by an extrasolar planet works. [NASA]Planet formation is a complex process with many aspects that we dont yet understand. Do environmental properties like host star metallicity, the density of nearby stars, or the intensity of the ambient radiation field affect the ability of planets to form? To answer these questions, we will ultimately need to search for planets around stars in a large variety of different environments in our galaxy.One way to detect recently formed, distant planets is by gravitational microlensing. In this process, light from a distant source star is bent by a lens star that is briefly located between us and the source. As the Earth moves, this momentary alignment causes a blip in the sources light curve that we can detect and planets hosted by the lens star can cause an additional observable bump.Artists impression of the Milky Way galaxy. The central bulge is much denserthan the surroundingdisk. [ESO/NASA/JPL-Caltech/M. Kornmesser/R. Hurt]Relative AbundancesMost source stars reside in the galactic bulge, so microlensing events can probe planetary systems at any distance between the Earth and the galactic bulge. This means that planet detections from microlensing could potentially be used to measure the relative abundances of exoplanets in different parts of our galaxy.A team of scientists led by Matthew Penny, a Sagan postdoctoral fellow at Ohio State University, set out to do just that. The group considered a sample of 31 exoplanetary systems detected by microlensing and asked the following question: are the planet abundances in the galactic bulge and the galactic disk the same?A Paucity of PlanetsTo answer this question, Penny and collaborators derived the expected

  10. The NASA-UC Eta-Earth Program: II. A Planet Orbiting HD 156668 with a Minimum Mass of Four Earth Masses

    CERN Document Server

    Howard, Andrew W; Marcy, Geoffrey W; Fischer, Debra A; Wright, Jason T; Henry, Gregory W; Isaacson, Howard; Valenti, Jeff A; Anderson, Jay; Piskunov, Nikolai E

    2010-01-01

    We report the discovery of HD 156668b, an extrasolar planet with a minimum mass of M_P sin i = 4.15 M_Earth. This planet was discovered through Keplerian modeling of precise radial velocities from Keck-HIRES and is the second super-Earth to emerge from the NASA-UC Eta-Earth Survey. The best-fit orbit is consistent with circular and has a period of P = 4.6455 d. The Doppler semi-amplitude of this planet, K = 1.89 m/s, is among the lowest ever detected, on par with the detection of GJ 581e using HARPS. A longer period (P ~ 2.3 yr), low-amplitude signal of unknown origin was also detected in the radial velocities and was filtered out of the data while fitting the short-period planet. Additional data are required to determine if the long-period signal is due to a second planet, stellar activity, or another source. Photometric observations using the Automated Photometric Telescopes at Fairborn Observatory show that HD 156668 (an old, quiet K3 dwarf) is photometrically constant over the radial velocity period to 0....

  11. Speckle Imaging and Spectroscopy of Kepler Exo-planet Transit Candidate Stars

    Science.gov (United States)

    Howell, Steve B.; Sherry, William; Horch, Elliott; Doyle, Laurance

    2010-02-01

    The NASA Kepler mission was successfully launched on 6 March 2009 and has begun science operations. Commissioning tests done early on in the mission have shown that for the bright sources, 10-15 ppm relative photometry can be achieved. This level assures we will detect Earth- like transits if they are present. ``Hot Jupiter" and similar large planet candidates have already been discovered and will be discussed at the Jan. AAS meeting as well as in a special issue of Science magazine to appear near years end. The plethora of variability observed is astounding and includes a number of eclipsing binaries which appear to have Jupiter and smaller size objects as an orbiting their body. Our proposal consists of three highly related objectives: 1) To continue our highly successful speckle imaging program which is a major component of defense to weed out false positive candidate transiting planets found by Kepler and move the rest to probable or certain exo-planet detections; 2) To obtain low resolution ``discovery" type spectra for planet candidate stars in order to provide spectral type and luminosity class indicators as well as a first look triage to eliminate binaries and rapid rotators; and 3) to obtain ~1Aresolution time ordered spectra of eclipsing binaries that are exo-planet candidates in order to obtain the velocity solution for the binary star, allowing its signal to be modeled and removed from the Keck or HET exo-planet velocity search. As of this writing, Kepler has produced a list of 227 exo-planet candidates which require false positive decision tree observations. Our proposed effort performs much of the first line of defense for the mission.

  12. A 12-year Activity Cycle for the Nearby Planet Host Star HD 219134

    Science.gov (United States)

    Johnson, Marshall C.; Endl, Michael; Cochran, William D.; Meschiari, Stefano; Robertson, Paul; MacQueen, Phillip J.; Brugamyer, Erik J.; Caldwell, Caroline; Hatzes, Artie P.; Ramírez, Ivan; Wittenmyer, Robert A.

    2016-04-01

    The nearby (6.5 pc) star HD 219134 was recently shown by Motalebi et al. and Vogt et al. to host several planets, the innermost of which is transiting. We present 27 years of radial velocity (RV) observations of this star from the McDonald Observatory Planet Search program, and 19 years of stellar activity data. We detect a long-period activity cycle measured in the Ca ii SHK index, with a period of 4230 ± 100 days (11.7 years), very similar to the 11 year solar activity cycle. Although the period of the Saturn-mass planet HD 219134 h is close to half that of the activity cycle, we argue that it is not an artifact due to stellar activity. We also find a significant periodicity in the SHK data due to stellar rotation with a period of 22.8 days. This is identical to the period of planet f identified by Vogt et al., suggesting that this RV signal might be caused by rotational modulation of stellar activity rather than a planet. Analysis of our RVs allows us to detect the long-period planet HD 219134 h and the transiting super-Earth HD 219134 b. Finally, we use our long time baseline to constrain the presence of longer period planets in the system, excluding to 1σ objects with M{sin}i\\gt 0.36{M}J at 12 years (corresponding to the orbital period of Jupiter) and M{sin}i\\gt 0.72{M}J at a period of 16.4 years (assuming a circular orbit for an outer companion).

  13. From Pixels to Planets

    Science.gov (United States)

    Brownston, Lee; Jenkins, Jon M.

    2015-01-01

    The Kepler Mission was launched in 2009 as NASAs first mission capable of finding Earth-size planets in the habitable zone of Sun-like stars. Its telescope consists of a 1.5-m primary mirror and a 0.95-m aperture. The 42 charge-coupled devices in its focal plane are read out every half hour, compressed, and then downlinked monthly. After four years, the second of four reaction wheels failed, ending the original mission. Back on earth, the Science Operations Center developed the Science Pipeline to analyze about 200,000 target stars in Keplers field of view, looking for evidence of periodic dimming suggesting that one or more planets had crossed the face of its host star. The Pipeline comprises several steps, from pixel-level calibration, through noise and artifact removal, to detection of transit-like signals and the construction of a suite of diagnostic tests to guard against false positives. The Kepler Science Pipeline consists of a pipeline infrastructure written in the Java programming language, which marshals data input to and output from MATLAB applications that are executed as external processes. The pipeline modules, which underwent continuous development and refinement even after data started arriving, employ several analytic techniques, many developed for the Kepler Project. Because of the large number of targets, the large amount of data per target and the complexity of the pipeline algorithms, the processing demands are daunting. Some pipeline modules require days to weeks to process all of their targets, even when run on NASA's 128-node Pleiades supercomputer. The software developers are still seeking ways to increase the throughput. To date, the Kepler project has discovered more than 4000 planetary candidates, of which more than 1000 have been independently confirmed or validated to be exoplanets. Funding for this mission is provided by NASAs Science Mission Directorate.

  14. Building Terrestrial Planets

    CERN Document Server

    Morbidelli, Alessandro; O`brien, David P; Raymond, Sean N; Walsh, Kevin J; 10.1146/annurev-earth-042711-105319

    2012-01-01

    This paper reviews our current understanding of terrestrial planets formation. The focus is on computer simulations of the dynamical aspects of the accretion process. Throughout the chapter, we combine the results of these theoretical models with geochemical, cosmochemical and chronological constraints, in order to outline a comprehensive scenario of the early evolution of our Solar System. Given that the giant planets formed first in the protoplanetary disk, we stress the sensitive dependence of the terrestrial planet accretion process on the orbital architecture of the giant planets and on their evolution. This suggests a great diversity among the terrestrial planets populations in extrasolar systems. Issues such as the cause for the different masses and accretion timescales between Mars and the Earth and the origin of water (and other volatiles) on our planet are discussed at depth.

  15. Seismology of Giant Planets

    CERN Document Server

    Gaulme, Patrick; Schmider, Francois-Xavier; Guillot, Tristan

    2014-01-01

    Seismology applied to giant planets could drastically change our understanding of their deep interiors, as it has happened with the Earth, the Sun, and many main-sequence and evolved stars. The study of giant planets' composition is important for understanding both the mechanisms enabling their formation and the origins of planetary systems, in particular our own. Unfortunately, its determination is complicated by the fact that their interior is thought not to be homogeneous, so that spectroscopic determinations of atmospheric abundances are probably not representative of the planet as a whole. Instead, the determination of their composition and structure must rely on indirect measurements and interior models. Giant planets are mostly fluid and convective, which makes their seismology much closer to that of solar-like stars than that of terrestrial planets. Hence, helioseismology techniques naturally transfer to giant planets. In addition, two alternative methods can be used: photometry of the solar light ref...

  16. SCANPS: a web server for iterative protein sequence database searching by dynamic programing, with display in a hierarchical SCOP browser.

    Science.gov (United States)

    Walsh, Thomas P; Webber, Caleb; Searle, Stephen; Sturrock, Shane S; Barton, Geoffrey J

    2008-07-01

    SCANPS performs iterative profile searching similar to PSI-BLAST but with full dynamic programing on each cycle and on-the-fly estimation of significance. This combination gives good sensitivity and selectivity that outperforms PSI-BLAST in domain-searching benchmarks. Although computationally expensive, SCANPS exploits onchip parallelism (MMX and SSE2 instructions on Intel chips) as well as MPI parallelism to give acceptable turnround times even for large databases. A web server developed to run SCANPS searches is now available at http://www.compbio.dundee.ac.uk/www-scanps. The server interface allows a range of different protein sequence databases to be searched including the SCOP database of protein domains. The server provides the user with regularly updated versions of the main protein sequence databases and is backed up by significant computing resources which ensure that searches are performed rapidly. For SCOP searches, the results may be viewed in a new tree-based representation that reflects the structure of the SCOP hierarchy; this aids the user in placing each hit in the context of its SCOP classification and understanding its relationship to other domains in SCOP.

  17. Dynamos of giant planets

    CERN Document Server

    Busse, F H; 10.1017/S1743921307000920

    2009-01-01

    Possibilities and difficulties of applying the theory of magnetic field generation by convection flows in rotating spherical fluid shells to the Giant Planets are outlined. Recent progress in the understanding of the distribution of electrical conductivity in the Giant Planets suggests that the dynamo process occurs predominantly in regions of semiconductivity. In contrast to the geodynamo the magnetic field generation in the Giant Planets is thus characterized by strong radial conductivity variations. The importance of the constraint on the Ohmic dissipation provided by the planetary luminosity is emphasized. Planetary dynamos are likely to be of an oscillatory type, although these oscillations may not be evident from the exterior of the planets.

  18. Challenges in Planet Formation

    CERN Document Server

    Morbidelli, Alessandro

    2016-01-01

    Over the past two decades, large strides have been made in the field of planet formation. Yet fundamental questions remain. Here we review our state of understanding of five fundamental bottlenecks in planet formation. These are: 1) the structure and evolution of protoplanetary disks; 2) the growth of the first planetesimals; 3) orbital migration driven by interactions between proto-planets and gaseous disk; 4) the origin of the Solar System's orbital architecture; and 5) the relationship between observed super-Earths and our own terrestrial planets. Given our lack of understanding of these issues, even the most successful formation models remain on shaky ground.

  19. The Search for Another Earth - Part II

    Indian Academy of Sciences (India)

    2016-10-01

    In the first part, we discussed the various methods for thedetection of planets outside the solar system known as theexoplanets. In this part, we will describe various kinds ofexoplanets. The habitable planets discovered so far and thepresent status of our search for a habitable planet similar tothe Earth will also be discussed.

  20. Trends in chemical ecology revealed with a personal computer program for searching data bases of scientific references and abstracts.

    Science.gov (United States)

    Byers, J A

    1992-09-01

    A compiled program, JCE-REFS.EXE (coded in the QuickBASIC language), for use on IBM-compatible personal computers is described. The program converts a DOS text file of current B-I-T-S (BIOSIS Information Transfer System) or BIOSIS Previews references into a DOS file of citations, including abstracts, in a general style used by scientific journals. The latter file can be imported directly into a word processor or the program can convert the file into a random access data base of the references. The program can search the data base for up to 40 text strings with Boolean logic. Selected references in the data base can be exported as a DOS text file of citations. Using the search facility, articles in theJournal of Chemical Ecology from 1975 to 1991 were searched for certain key words in regard to semiochemicals, taxa, methods, chemical classes, and biological terms to determine trends in usage over the period. Positive trends were statistically significant in the use of the words: semiochemical, allomone, allelochemic, deterrent, repellent, plants, angiosperms, dicots, wind tunnel, olfactometer, electrophysiology, mass spectrometry, ketone, evolution, physiology, herbivore, defense, and receptor. Significant negative trends were found for: pheromone, vertebrates, mammals, Coleoptera, Scolytidae,Dendroctonus, lactone, isomer, and calling.

  1. What do Constraint Programming Users Want to See? Exploring the Role of Visualisation in Profiling of Models and Search.

    Science.gov (United States)

    Goodwin, Sarah; Mears, Christopher; Dwyer, Tim; de la Banda, Maria Garcia; Tack, Guido; Wallace, Mark

    2017-01-01

    Constraint programming allows difficult combinatorial problems to be modelled declaratively and solved automatically. Advances in solver technologies over recent years have allowed the successful use of constraint programming in many application areas. However, when a particular solver's search for a solution takes too long, the complexity of the constraint program execution hinders the programmer's ability to profile that search and understand how it relates to their model. Therefore, effective tools to support such profiling and allow users of constraint programming technologies to refine their model or experiment with different search parameters are essential. This paper details the first user-centred design process for visual profiling tools in this domain. We report on: our insights and opportunities identified through an on-line questionnaire and a creativity workshop with domain experts carried out to elicit requirements for analytical and visual profiling techniques; our designs and functional prototypes realising such techniques; and case studies demonstrating how these techniques shed light on the behaviour of the solvers in practice.

  2. Exozodiacal Dust and Direct Imaging of Extrasolar Planets

    Science.gov (United States)

    Kuchner, Marc

    2008-01-01

    Direct imaging of extrasolar planets means contending with dust from extrasolar asteroids and comets. This 'exozodiacal dust' creates a structured background light that can easily outshine the light from an exoEarth and confuse a planet-search mission like TPF or TOPS. But exozodiacal dust can be both friend and foe: planets can stir dust clouds into patterns that reveal the presence of the planet and constrain its mass and orbit. I'll describe some recent research on this topic: 3-D dynamical models of dust clouds with planets and searches for exozodiacal dust with the Keck Interferometer. The author also offers a prediction for the typical zodiacal dust background found around solar analogs, based on seafloor sediment data.

  3. Search Combinators

    CERN Document Server

    Schrijvers, Tom; Wuille, Pieter; Samulowitz, Horst; Stuckey, Peter J

    2012-01-01

    The ability to model search in a constraint solver can be an essential asset for solving combinatorial problems. However, existing infrastructure for defining search heuristics is often inadequate. Either modeling capabilities are extremely limited or users are faced with a general-purpose programming language whose features are not tailored towards writing search heuristics. As a result, major improvements in performance may remain unexplored. This article introduces search combinators, a lightweight and solver-independent method that bridges the gap between a conceptually simple modeling language for search (high-level, functional and naturally compositional) and an efficient implementation (low-level, imperative and highly non-modular). By allowing the user to define application-tailored search strategies from a small set of primitives, search combinators effectively provide a rich domain-specific language (DSL) for modeling search to the user. Remarkably, this DSL comes at a low implementation cost to the...

  4. Possibilities for the detection of microbial life on extrasolar planets.

    Science.gov (United States)

    Knacke, Roger F

    2003-01-01

    We consider possibilities for the remote detection of microbial life on extrasolar planets. The Darwin/Terrestrial Planet Finder (TPF) telescope concepts for observations of terrestrial planets focus on indirect searches for life through the detection of atmospheric gases related to life processes. Direct detection of extraterrestrial life may also be possible through well-designed searches for microbial life forms. Satellites in Earth orbit routinely monitor colonies of terrestrial algae in oceans and lakes by analysis of reflected ocean light in the visible region of the spectrum. These remote sensing techniques suggest strategies for extrasolar searches for signatures of chlorophylls and related photosynthetic compounds associated with life. However, identification of such life-related compounds on extrasolar planets would require observations through strong, interfering absorptions and scattering radiances from the remote atmospheres and landmasses. Techniques for removal of interfering radiances have been extensively developed for remote sensing from Earth orbit. Comparable techniques would have to be developed for extrasolar planet observations also, but doing so would be challenging for a remote planet. Darwin/TPF coronagraph concepts operating in the visible seem to be best suited for searches for extrasolar microbial life forms with instruments that can be projected for the 2010-2020 decades, although resolution and signal-to-noise ratio constraints severely limit detection possibilities on terrestrial-type planets. The generation of telescopes with large apertures and extremely high spatial resolutions that will follow Darwin/TPF could offer striking possibilities for the direct detection of extrasolar microbial life.

  5. FIRST HABITABLE PLANET DISCOVEREO

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    20 light years away from our solar system, there is a planet called "Gliese 581d" which has conditions that could support Earth-like life, including possible oceans and rainfall. On May. 19, 20l 1, the planet has been the first to be officially declared habitable by French scientists.

  6. Map-A-Planet

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Map-A-Planet website allows users to create and download custom image maps of planets and satellites from a variety of missions in an easy to use web interface

  7. The Extra-Solar Planet Imager (ESPI)

    CERN Document Server

    Nisenson, P; Geary, J; Holman, M; Korzennik, S G; Noyes, R W; Papaliolios, C; Sasselov, D D; Fischer, D; Gezari, D; Lyon, R G; Gonsalves, R; Hardesty, C; Harwit, M; Marley, M S; Neufeld, D A; Ridgway, S T

    2002-01-01

    ESPI has been proposed for direct imaging and spectral analysis of giant planets orbiting solar-type stars. ESPI extends the concept suggested by Nisenson and Papaliolios (2001) for a square aperture apodized telescope that has sufficient dynamic range to directly detect exo-planets. With a 1.5 M square mirror, ESPI can deliver high dynamic range imagery as close as 0.3 arcseconds to bright sources, permitting a sensitive search for exoplanets around nearby stars and a study of their characteristics in reflected light.

  8. Extrasolar Planet Interactions

    CERN Document Server

    Barnes, Rory

    2008-01-01

    The dynamical interactions of planetary systems may be a clue to their formation histories. Therefore, the distribution of these interactions provides important constraints on models of planet formation. We focus on each system's apsidal motion and proximity to dynamical instability. Although only ~25 multiple planet systems have been discovered to date, our analyses in these terms have revealed several important features of planetary interactions. 1) Many systems interact such that they are near the boundary between stability and instability. 2) Planets tend to form such that at least one planet's eccentricity periodically drops to near zero. 3) Mean-motion resonant pairs would be unstable if not for the resonance. 4) Scattering of approximately equal mass planets is unlikely to produce the observed distribution of apsidal behavior. 5) Resonant interactions may be identified through calculating a system's proximity to instability, regardless of knowledge of angles such as mean longitude and longitude of peri...

  9. Primordial Planet Formation

    CERN Document Server

    Schild, Rudolph E

    2010-01-01

    Recent spacecraft observations exploring solar system properties impact standard paradigms of the formation of stars, planets and comets. We stress the unexpected cloud of microscopic dust resulting from the DEEP IMPACT mission, and the existence of molten nodules in STARDUST samples. And the theory of star formation does not explain the common occurrence of binary and multiple star systems in the standard gas fragmentation scenario. No current theory of planet formation can explain the iron core of the earth, under oceans of water. These difficulties are avoided in a scenario where the planet mass objects form primordially and are today the baryonic dark matter. They have been detected in quasar microlensing and anomalous quasar radio brightening bursts. The primordial planets often concentrate together to form a star, with residual matter seen in pre-stellar accretion discs around the youngest stars. These primordial planet mass bodies were formed of hydrogen-helium, aggregated in dense clumps of a trillion...

  10. Illuminating the Origins of Planets with Solar Twins

    Science.gov (United States)

    Bedell, Megan

    2017-01-01

    It is now well established that stellar photospheric compositions can act as a fossil record of the protostellar environments in which planets form. Stellar spectroscopy of planet-hosting stars is therefore a valuable source of information about chemical conditions for planet formation. However, the difficulty of resolving planet-scale abundance differences in the photospheres of stars requires a unique approach. I will present recent results from a five-year-long radial velocity planet survey and complementary stellar spectroscopy focusing on solar twins. By restricting our sample to a set of "twin" stars, we demonstrate that we can resolve changes in stellar compositions on the scale of only a few Earth masses, potentially offering a new observational window into planet formation signatures. The techniques developed through our solar twin program will become increasingly valuable as we enter the TESS era of bright, spectroscopy-friendly planet host stars.

  11. The Berkeley piggyback SETI program - SERENDIP II. [Search for Extraterrestrial Radio Emission from Nearby Developed Intelligent Populations

    Science.gov (United States)

    Bowyer, S.; Werthimer, D.; Lindsay, V.

    1988-01-01

    The SERENDIP (Search for Extraterrestrial Radio Emission from Nearby Developed Intelligent Populations) II system is currently operating at NRAO's 300-ft telescope in Greenbank, WV. The paper reports on the characteristics of this system in combination with this telescope, as well as elements of an off-line analysis program which are intended to identify signals of special interest. The sensitivity and relative probability of acquisition are evaluated.

  12. Planet Hunters: A Transiting Circumbinary Planet in a Quadruple Star System

    CERN Document Server

    Schwamb, Megan E; Carter, Joshua A; Welsh, William F; Fischer, Debra A; Torres, Guillermo; Howard, Andrew W; Crepp, Justin R; Keel, William C; Lintott, Chris J; Kaib, Nathan A; Terrell, Dirk; Gagliano, Robert; Jek, Kian J; Parrish, Michael; Smith, Arfon M; Lynn, Stuart; Simpson, Robert J; Giguere, Matthew J; Schawinski, Kevin

    2012-01-01

    We report the discovery and confirmation of a transiting circumbinary planet (PH1) around KIC 4862625, an eclipsing binary in the Kepler field. The planet was discovered by volunteers searching the first six Quarters of publicly available Kepler data as part of the Planet Hunters citizen science project. Transits of the planet across the larger and brighter of the eclipsing stars are detectable by visual inspection every ~137 days, with seven transits identified in Quarters 1-11. The physical and orbital parameters of both the host stars and planet were obtained via a photometric-dynamical model, simultaneously fitting both the measured radial velocities and the Kepler light curve of KIC 4862625.The 6.18 $\\pm$ 0.17 Earth radii planet orbits outside the 20-day orbit of an eclipsing binary consisting of an F dwarf (1.734 +/- 0.044 Solar radii, 1.528 +/- 0.087 Solar masses) and M dwarf (0.378 +/0 0.023 Solar radii, 0.408 +/- 0.024 solar masses). For the planet, we find an upper mass limit of 169 Earth masses(0.5...

  13. Follow-up of K2 planet candiates with the LCOGT network

    Science.gov (United States)

    Dragomir, Diana; Bayliss, Daniel; Colón, Knicole; Cochran, William; Zhou, George; Brown, Timothy; Shporer, Avi; Espinoza, Nestor; Fulton, Benjamin

    2015-12-01

    K2 has proven to be an outstanding successor to the Kepler mission. It has already revealed dozens of new planet candidates, and unlike those found by the primary mission, many of these systems’ host stars are sufficiently bright to allow extensive follow-up observations. This is especially important since each of the K2 observing campaigns are only ~80 days long, leaving the community with the discovery of exciting new systems but often not enough time coverage to enable a thorough characterization of these systems.We are leading a large effort to observe K2 transiting planet candidates with the LCOGT telescope network. LCOGT’s longitudinal coverage, multiple identical telescopes per site and automated queue observing make it an ideal facility for fast, high-precision and multi-color follow-up. Our program focuses on specific aspects of K2 follow-up for which the network is especially powerful: period determination for candidates with fewer than three K2 transits; transit timing variation monitoring to measure planetary masses, orbital parameters and to search for additional planets in multiple systems; and multi-color photometry to vet planet candidates and carry-out preliminary atmospheric spectroscopy.We will present new results for a selection of systems observed so far through this program. These include K2-19, a multi-planet system extremely close to 3:2 resonance and experiencing transit timing variations with amplitudes as large as one hour; EPIC201702477, a long-period planet with only two K2 transits; WASP-47, a system hosting a hot Jupiter and two K2-discovered small planets; and EPIC201637175b, a disintegrating rocky planet.Our program demonstrates that LCOGT is uniquely positioned to be the primary ground-based photometric follow-up resource for K2 exoplanet discoveries, but also for the numerous bright systems that will result from the TESS mission. LCOGT photometry complements ongoing radial velocity and atmospheric spectroscopy efforts to

  14. Precursor Science for the Terrestrial Planet Finder

    Science.gov (United States)

    Lawson, P. R. (Editor); Unwin, S. C. (Editor); Beichman, C. A. (Editor)

    2004-01-01

    This document outlines a path for the development of the field of extrasolar planet research, with a particular emphasis on the goals of the Terrestrial Planet Finder (TPF). Over the past decade, a new field of research has developed, the study of extrasolar planetary systems, driven by the discovery of massive planets around nearby stars. The planet count now stands at over 130. Are there Earth-like planets around nearby stars? Might any of those planets be conducive to the formation and maintenance of life? These arc the questions that TPF seeks to answer. TPF will be implemented as a suite of two space observatories, a 6-m class optical coronagraph, to be launched around 20 14, and a formation flying mid-infrared interferometer, to be launched sometime prior to 2020. These facilities will survey up to 165 or more nearby stars and detect planets like Earth should they be present in the 'habitable zone' around each star. With observations over a broad wavelength range, TPF will provide a robust determination of the atmospheric composition of planets to assess habitability and the presence of life. At this early stage of TPF's development, precursor observational and theoretical programs are essential to help define the mission, to aid our understanding of the planets that TPF could discover, and to characterize the stars that TPF will eventually study. This document is necessarily broad in scope because the significance of individual discoveries is greatly enhanced when viewed in thc context of the field as a whole. This document has the ambitious goal of taking us from our limited knowledge today, in 2004, to the era of TPF observations in the middle of the next decade. We must use the intervening years wisely. This document will be reviewed annually and updated as needed. The most recent edition is available online at http://tpf.jpl.nasa.gov/ or by email request to lawson@hucy.jpl.nasa.gov

  15. Planets a very short introduction

    CERN Document Server

    Rothery, David A

    2010-01-01

    Planets: A Very Short Introduction demonstrates the excitement, uncertainties, and challenges faced by planetary scientists, and provides an overview of our Solar System and its origins, nature, and evolution. Terrestrial planets, giant planets, dwarf planets and various other objects such as satellites (moons), asteroids, trans-Neptunian objects, and exoplanets are discussed. Our knowledge about planets has advanced over the centuries, and has expanded at a rapidly growing rate in recent years. Controversial issues are outlined, such as What qualifies as a planet? What conditions are required for a planetary body to be potentially inhabited by life? Why does Pluto no longer have planet status? And Is there life on other planets?

  16. The NASA-UC-UH Eta-Earth program. IV. A low-mass planet orbiting an M dwarf 3.6 PC from Earth

    Energy Technology Data Exchange (ETDEWEB)

    Howard, Andrew W. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Marcy, Geoffrey W.; Isaacson, Howard [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Fischer, Debra A.; Boyajian, Tabetha S. [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Muirhead, Philip S.; Becker, Juliette C. [Department of Astrophysics, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States); Henry, Gregory W. [Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Boulevard, Box 9501, Nashville, TN 37209 (United States); Von Braun, Kaspar [NASA Exoplanet Science Institute, California Institute of Technology, Pasadena, CA 91125 (United States); Wright, Jason T. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Johnson, John Asher [Center for Planetary Astronomy, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States)

    2014-10-10

    We report the discovery of a low-mass planet orbiting Gl 15 A based on radial velocities from the Eta-Earth Survey using HIRES at Keck Observatory. Gl 15 Ab is a planet with minimum mass Msin i = 5.35 ± 0.75 M {sub ⊕}, orbital period P = 11.4433 ± 0.0016 days, and an orbit that is consistent with circular. We characterize the host star using a variety of techniques. Photometric observations at Fairborn Observatory show no evidence for rotational modulation of spots at the orbital period to a limit of ∼0.1 mmag, thus supporting the existence of the planet. We detect a second RV signal with a period of 44 days that we attribute to rotational modulation of stellar surface features, as confirmed by optical photometry and the Ca II H and K activity indicator. Using infrared spectroscopy from Palomar-TripleSpec, we measure an M2 V spectral type and a sub-solar metallicity ([M/H] = –0.22, [Fe/H] = –0.32). We measure a stellar radius of 0.3863 ± 0.0021 R {sub ☉} based on interferometry from CHARA.

  17. The NASA-UC-UH Eta-Earth Program: IV. A Low-mass Planet Orbiting an M Dwarf 3.6 PC from Earth

    CERN Document Server

    Howard, Andrew W; Fischer, Debra A; Isaacson, Howard; Muirhead, Philip S; Henry, Gregory W; Boyajian, Tabetha S; von Braun, Kaspar; Becker, Juliette C; Wright, Jason T; Johnson, John Asher

    2014-01-01

    We report the discovery of a low-mass planet orbiting Gl 15 A based on radial velocities from the Eta-Earth Survey using HIRES at Keck Observatory. Gl 15 Ab is a planet with minimum mass Msini = 5.35 $\\pm$ 0.75 M$_\\oplus$, orbital period P = 11.4433 $\\pm$ 0.0016 days, and an orbit that is consistent with circular. We characterize the host star using a variety of techniques. Photometric observations at Fairborn Observatory show no evidence for rotational modulation of spots at the orbital period to a limit of ~0.1 mmag, thus supporting the existence of the planet. We detect a second RV signal with a period of 44 days that we attribute to rotational modulation of stellar surface features, as confirmed by optical photometry and the Ca II H & K activity indicator. Using infrared spectroscopy from Palomar-TripleSpec, we measure an M2 V spectral type and a sub-solar metallicity ([M/H] = -0.22, [Fe/H] = -0.32). We measure a stellar radius of 0.3863 $\\pm$ 0.0021 R$_\\odot$ based on interferometry from CHARA.

  18. The NASA-UC-UH ETA-Earth Program. IV. A Low-mass Planet Orbiting an M Dwarf 3.6 PC from Earth

    Science.gov (United States)

    Howard, Andrew W.; Marcy, Geoffrey W.; Fischer, Debra A.; Isaacson, Howard; Muirhead, Philip S.; Henry, Gregory W.; Boyajian, Tabetha S.; von Braun, Kaspar; Becker, Juliette C.; Wright, Jason T.; Johnson, John Asher

    2014-10-01

    We report the discovery of a low-mass planet orbiting Gl 15 A based on radial velocities from the Eta-Earth Survey using HIRES at Keck Observatory. Gl 15 Ab is a planet with minimum mass Msin i = 5.35 ± 0.75 M ⊕, orbital period P = 11.4433 ± 0.0016 days, and an orbit that is consistent with circular. We characterize the host star using a variety of techniques. Photometric observations at Fairborn Observatory show no evidence for rotational modulation of spots at the orbital period to a limit of ~0.1 mmag, thus supporting the existence of the planet. We detect a second RV signal with a period of 44 days that we attribute to rotational modulation of stellar surface features, as confirmed by optical photometry and the Ca II H & K activity indicator. Using infrared spectroscopy from Palomar-TripleSpec, we measure an M2 V spectral type and a sub-solar metallicity ([M/H] = -0.22, [Fe/H] = -0.32). We measure a stellar radius of 0.3863 ± 0.0021 R ⊙ based on interferometry from CHARA. Based on observations obtained at the W. M. Keck Observatory, which is operated jointly by the University of California and the California Institute of Technology. Keck time was granted for this project by the University of Hawaii, the University of California, and NASA.

  19. The Evryscope and extrasolar planets

    Science.gov (United States)

    Fors, Octavi; Law, Nicholas Michael; Ratzloff, Jeffrey; del Ser, Daniel; Wulfken, Philip J.; Kavanaugh, Dustin

    2015-08-01

    The Evryscope (Law et al. 2015) is a 24-camera hemispherical all-sky gigapixel telescope (8,000 sq.deg. FoV) with rapid cadence (2mins exposure, 4sec readout) installed at CTIO. Ground-based single-station transiting surveys typically suffer from light curve sparsity and suboptimal efficiency because of their limited field of view (FoV), resulting in incomplete and biased detections. In contrast, the Evryscope offers 97% survey efficiency and one of the single-station most continuous and simultaneous monitoring of millions of stars (only limited by the day-night window).This unique facility is capable of addressing new and more extensive planetary populations, including: 1) for the first time, continuously monitor every 2mins a set of ~1000 bright white dwarfs (WDs). This will allow us to put constraints on the habitable planet fraction of Ceres-size planetesimals at the level of 30%, only in a survey timescales of a few weeks, as well as first-time testing planetary evolution models beyond the AGB phase. 2) search for rocky planets in the habitable zone around ~5,000 bright, nearby M-dwarfs. 3) synergies between Evryscope and upcoming exoplanets missions (e.g. TESS, PLATO) are also promising for target pre-imaging characterization, and increasing the giant planet yield by recovering multiple transits from planets seen as single transit events from space. 4) all-sky 2-min cadence of rare microlensing events of nearby stars. 5) all-sky continuous survey of microlensing events of nearby stars at 2mins cadence. 6) increase the census of giant planets around ~70,000 nearby, bright (g<10) solar-type stars, whose atmospheres can be characterized by follow-up observations. We are developing new data analysis algorithms to address the above scientific goals: from detecting the extremely short and faint transits around WDs, to disentangle planetary signals from very bright stars, and to combine space-based light curves with the Evryscope's ones. We will present the first

  20. Comparative Climatology of Terrestrial Planets

    Science.gov (United States)

    Mackwell, Stephen J.; Simon-Miller, Amy A.; Harder, Jerald W.; Bullock, Mark A.

    Public awareness of climate change on Earth is currently very high, promoting significant interest in atmospheric processes. We are fortunate to live in an era where it is possible to study the climates of many planets, including our own, using spacecraft and groundbased observations as well as advanced computational power that allows detailed modeling. Planetary atmospheric dynamics and structure are all governed by the same basic physics. Thus differences in the input variables (such as composition, internal structure, and solar radiation) among the known planets provide a broad suite of natural laboratory settings for gaining new understanding of these physical processes and their outcomes. Diverse planetary settings provide insightful comparisons to atmospheric processes and feedbacks on Earth, allowing a greater understanding of the driving forces and external influences on our own planetary climate. They also inform us in our search for habitable environments on planets orbiting distant stars, a topic that was a focus of Exoplanets, the preceding book in the University of Arizona Press Space Sciences Series. Quite naturally, and perhaps inevitably, our fascination with climate is largely driven toward investigating the interplay between the early development of life and the presence of a suitable planetary climate. Our understanding of how habitable planets come to be begins with the worlds closest to home. Venus, Earth, and Mars differ only modestly in their mass and distance from the Sun, yet their current climates could scarcely be more divergent. Our purpose for this book is to set forth the foundations for this emerging science and to bring to the forefront our current understanding of atmospheric formation and climate evolution. Although there is significant comparison to be made to atmospheric processes on nonterrestrial planets in our solar system — the gas and ice giants — here we focus on the terrestrial planets, leaving even broader comparisons

  1. Imaging Young Planets From Ground and Space

    CERN Document Server

    Beichman, Charles A; Trauger, John T; Greene, Thomas P; Oppenheimer, Ben; Sivaramakrishnan, Anand; Doyon, Rene; Boccaletti, Antony; Barman, Travis S; Rieke, Marcia

    2010-01-01

    High contrast imaging can find and characterize gas giant planets around nearby young stars and the closest M stars, complementing radial velocity and astrometric searches by exploring orbital separations inaccessible to indirect methods. Ground-based coronagraphs are already probing within 25 AU of nearby young stars to find objects as small as ~ 3 Jupiter masses. This paper compares near-term and future ground-based capabilities with high contrast imaging modes of the James Webb Space Telescope (JWST). Monte Carlo modeling reveals that JWST can detect planets with masses as small as 0.2 MJup across a broad range of orbital separations. We present new calculations for planet brightness as a function of mass and age for specific JWST filters and extending to 0.1 MJup.

  2. Why 400 Years to Discover Countless Planets?

    Science.gov (United States)

    Carr, Paul H.

    2011-04-01

    In 1584, Dominican monk Giordano Bruno envisioned the stars as "countless suns with countless earths, all rotating around their suns." Searching for intellectual freedom, he fled his native Italy to Protestant Switzerland and Germany, but in 1600 the Roman Inquisition condemned him for heresy. He was burned at the stake. Fast-forwarding to 1995, the Swiss astronomers Michel Mayor and Didier Queloz announced the discovery of a planet orbiting a star similar to our sun (51 Pegasi). In 2010, 500 planets had been found orbiting 421 stars. On Feb 2, 2011, NASA announced 1200 planet candidates. It took 400 years for telescope technology to advance and for Copernicus, Galileo, Newton, Bradley, and Foucault to make major contributions, culminating in today's astrophysics with digital imaging and processing. Contrasting with Bruno, in 2010 Dominican Francisco Ayala, who had been president of the Sigma Xi and AAAS, won the 1.6M Templeton Prize for affirming life's spiritual dimension.

  3. From Disks to Planets

    Science.gov (United States)

    Youdin, Andrew N.; Kenyon, Scott J.

    This pedagogical chapter covers the theory of planet formation, with an emphasis on the physical processes relevant to current research. After summarizing empirical constraints from astronomical and geophysical data, we describe the structure and evolution of protoplanetary disks. We consider the growth of planetesimals and of larger solid protoplanets, followed by the accretion of planetary atmospheres, including the core accretion instability. We also examine the possibility that gas disks fragment directly into giant planets and/or brown dwarfs. We defer a detailed description of planet migration and dynamical evolution to other work, such as the complementary chapter in this series by Morbidelli.

  4. Planets under pressure

    Science.gov (United States)

    Jeanloz, Raymond

    2009-04-01

    Deep inside the planet Jupiter, diamonds hail down from hydrocarbon clouds as intense atmospheric pressures break methane into its atomic components. Further in - but still only 15% of the way to the planet's centre - the pressure reaches a million times that of the Earth's atmosphere. This is enough to transform hydrogen from the transparent, insulating gas we know at our planet's surface into a metallic fluid that sustains Jupiter's huge magnetic field. Even diamond is not forever: at pressures of 8-10 million atmospheres it is transformed into an opaque, metallic form of carbon, rather than the familiar transparent crystal.

  5. Kepler's first rocky planet

    DEFF Research Database (Denmark)

    Batalha, N.M.; Borucki, W.J.; Bryson, S.T.

    2011-01-01

    NASA's Kepler Mission uses transit photometry to determine the frequency of Earth-size planets in or near the habitable zone of Sun-like stars. The mission reached a milestone toward meeting that goal: the discovery of its first rocky planet, Kepler-10b. Two distinct sets of transit events were...... tests on the photometric and pixel flux time series established the viability of the planet candidates triggering ground-based follow-up observations. Forty precision Doppler measurements were used to confirm that the short-period transit event is due to a planetary companion. The parent star is bright...

  6. Planet Hunters: A Transiting Circumbinary Planet in a Quadruple Star System

    Science.gov (United States)

    Schwamb, Megan E.; Orosz, Jerome A.; Carter, Joshua A.; Welsh, William F.; Fischer, Debra A.; Torres, Guillermo; Howard, Andrew W.; Crepp, Justin R.; Keel, William C.; Lintott, Chris J.; Kaib, Nathan A.; Terrell, Dirk; Gagliano, Robert; Jek, Kian J.; Parrish, Michael; Smith, Arfon M.; Lynn, Stuart; Simpson, Robert J.; Giguere, Matthew J.; Schawinski, Kevin

    2013-05-01

    We report the discovery and confirmation of a transiting circumbinary planet (PH1b) around KIC 4862625, an eclipsing binary in the Kepler field. The planet was discovered by volunteers searching the first six Quarters of publicly available Kepler data as part of the Planet Hunters citizen science project. Transits of the planet across the larger and brighter of the eclipsing stars are detectable by visual inspection every ~137 days, with seven transits identified in Quarters 1-11. The physical and orbital parameters of both the host stars and planet were obtained via a photometric-dynamical model, simultaneously fitting both the measured radial velocities and the Kepler light curve of KIC 4862625. The 6.18 ± 0.17 R ⊕ planet orbits outside the 20 day orbit of an eclipsing binary consisting of an F dwarf (1.734 ± 0.044 R ⊙, 1.528 ± 0.087 M ⊙) and M dwarf (0.378 ± 0.023 R ⊙, 0.408 ± 0.024 M ⊙). For the planet, we find an upper mass limit of 169 M ⊕ (0.531 Jupiter masses) at the 99.7% confidence level. With a radius and mass less than that of Jupiter, PH1b is well within the planetary regime. Outside the planet's orbit, at ~1000 AU, a previously unknown visual binary has been identified that is likely bound to the planetary system, making this the first known case of a quadruple star system with a transiting planet.

  7. First results from the RAO Variable Star Search Program: I. Background, Procedure, and Results from RAO Field 1

    CERN Document Server

    Williams, Michael D

    2011-01-01

    We describe an ongoing variable star search program and present the first reduced results of a search in a 19 square degree (4.4\\circle x 4.4\\circle) field centered on J2000 {\\alpha} = 22:03:24, {\\delta} = +18:54:32. The search was carried out with the Baker-Nunn Patrol Camera located at the Rothney Astrophysical Observatory in the foothills of the Canadian Rockies. A total of 26,271 stars were detected in the field, over a range of about 11-15 (instrumental) magnitudes. Our image processing made use of the IRAF version of the DAOPHOT aperture photometry routine and we used the ANOVA method to search for periodic variations in the light curves. We formally detected periodic variability in 35 stars, that we tentatively classify according to light curve characteristics: 6 EA (Algol), 5 EB ({\\beta} Lyrae), 19 EW (W UMa), and 5 RR (RR Lyrae) stars. Eleven of the detected variable stars have been reported previously in the literature. The eclipsing binary light curves have been analyzed with a package of light cur...

  8. Managing Planet Earth.

    Science.gov (United States)

    Clark, William C.

    1989-01-01

    Discusses the human use of the planet earth. Describes the global patterns and the regional aspects of change. Four requirements for the cultivation of leadership and institutional competence are suggested. Lists five references for further reading. (YP)

  9. Search for the northwest passage: the assignation of NSP (non-point source pollution) rights in nutrient trading programs.

    Science.gov (United States)

    Collentine, D

    2002-01-01

    The search for solutions to the problem of non-point source pollution (NSP) includes alternatives based on theories associated with the use of tradable pollution permits. Tradable permit programs have received significant support as a promising policy for the reduction of effluent discharges but programs in practice have not been regarded as successful. The lack of success is ascribed to the design of the programs. However, this may be a design problem which is insurmountable due to the nature of the NSP problem. Tradable permit solutions are based on an assumption that the assignation of quantifiable rights to both point and nonpoint sources, based on some predetermined ambient water quality measure, is possible. The conclusion here is that there are significant features particular to NSP that hinder the introduction of rights and significantly decrease the utility of tradable permit solutions.

  10. The Radiometric Bode's Law and Extrasolar Planets

    CERN Document Server

    Lazio, T J W; Dietrick, J; Greenlees, E; Hogan, E; Jones, C; Hennig, L A

    2004-01-01

    We predict the radio flux densities of the extrasolar planets in the current census, making use of an empirical relation--the radiometric Bode's Law--determined from the five ``magnetic'' planets in the solar system (Earth and the four gas giants). Radio emission from these planets results from solar-wind powered electron currents depositing energy in the magnetic polar regions. We find that most of the known extrasolar planets should emit in the frequency range 10--1000 MHz and, under favorable circumstances, have typical flux densities as large as 1 mJy. We also describe an initial, systematic effort to search for radio emission in low radio frequency images acquired with the Very Large Array. The limits set by the VLA images (~ 300 mJy) are consistent with, but do not provide strong constraints on, the predictions of the model. Future radio telescopes, such as the Low Frequency Array (LOFAR) and the Square Kilometer Array (SKA), should be able to detect the known extrasolar planets or place austere limits ...

  11. Finding Planet Nine: a Monte Carlo approach

    CERN Document Server

    Marcos, C de la Fuente

    2016-01-01

    Planet Nine is a hypothetical planet located well beyond Pluto that has been proposed in an attempt to explain the observed clustering in physical space of the perihelia of six extreme trans-Neptunian objects or ETNOs. The predicted approximate values of its orbital elements include a semimajor axis of 700 au, an eccentricity of 0.6, an inclination of 30 degrees, and an argument of perihelion of 150 degrees. Searching for this putative planet is already under way. Here, we use a Monte Carlo approach to create a synthetic population of Planet Nine orbits and study its visibility statistically in terms of various parameters and focusing on the aphelion configuration. Our analysis shows that, if Planet Nine exists and is at aphelion, it might be found projected against one out of four specific areas in the sky. Each area is linked to a particular value of the longitude of the ascending node and two of them are compatible with an apsidal antialignment scenario. In addition and after studying the current statistic...

  12. Planet Host Stars: Mass, Age and Kinematics

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    We determine the mass, age and kinematics of 51 extra-solar planet host stars. The results are then used to search for signs of connection of the data with metallicity and to investigate the population nature. We find that the increase in mean metallicity with stellar mass is similar to that in normal field stars, so it seems unsuitable to use this relation as a constraint on the theory of planet formation. The age and kinematic distributions seem to favour the metallicity of extra-solar planet host stars being initial. Although the kinematic data of these stars indicate their origin from two populations - the thin and the thick disks, kinematics may not help in the maintenance of the planet around the host. Stars with planets, brown dwarfs or stellar companions are sorted into three groups and re-investigated separately for their formation mechanism. The main results indicate that stars with M2 < 25MJ have [Fe/H] > -0.1 and a wide period range, but there are no other differences.Thus, there does not seem to be any physically distinguishable characteristics among the three star groups.

  13. SAM: The "Search and Match" Computer Program of the Escherichia coli Genetic Stock Center

    Science.gov (United States)

    Bachmann, B. J.; And Others

    1973-01-01

    Describes a computer program used at a genetic stock center to locate particular strains of bacteria. The program can match up to 30 strain descriptions requested by a researcher with the records on file. Uses of this particular program can be made in many fields. (PS)

  14. The planet Mercury (1971)

    Science.gov (United States)

    1972-01-01

    The physical properties of the planet Mercury, its surface, and atmosphere are presented for space vehicle design criteria. The mass, dimensions, mean density, and orbital and rotational motions are described. The gravity field, magnetic field, electromagnetic radiation, and charged particles in the planet's orbit are discussed. Atmospheric pressure, temperature, and composition data are given along with the surface composition, soil mechanical properties, and topography, and the surface electromagnetic and temperature properties.

  15. Red worlds: Spitzer exploration of a compact system of temperate terrestrial planets transiting a nearby Jupiter-sized star

    Science.gov (United States)

    Gillon, Michael; Burdanov, Artem; Delrez, Laetitia; Jehin, Emmanuel; Magain, Pierre; Van Grootel, Valerie; Bolmont, Emeline; Leconte, Jeremy; Raymond, Sean; Selsis, Franck; Demory, Brice-Olivier; Queloz, Didier; Triaud, Amaury; de Wit, Julien; Burgasser, Adam; Carey, Sean; Ingalls, Jim; Lederer, Sue; Agol, Eric; Deck, Katherine

    2016-08-01

    The recently detected TRAPPIST-1 planetary system represents a unique opportunity to extend the nascent field of comparative exoplanetology into the realm of temperate terrestrial worlds. It is composed of at least three Earth-sized planets similar in sizes and irradiations to Earth and Venus transiting an ultra-cool dwarf star only 39 light-years away. Thanks to the Jupiter-size and infrared brightness of their host star, the planets are amenable for detailed atmospheric characterization with JWST, including for biosignatures detection. Our Spitzer Exploration Science Program aims to prepare and optimize the detailed study of this fascinating planetary system through the two following complementary sub-programs: (1) a 480 hrs continuous monitoring of the star to explore its full inner system up to its ice line in a search for any other transiting object(s) (planet, moon, Trojan) with a sensitivity high enough to detect any body as small as Ganymede, and (2) the observation of ~130 transits of the planets (520 hrs). This second part has two goals. First, to measure precisely the planets' masses and eccentricities through the Transit Timing Variations method, to constrain strongly their compositions and energy budgets. Secondly, to measure with an extremely high precision the planets' effective radii at 4.5 microns to assess, when combined with future HST/WFC3 observations, the presence of an atmosphere around them. The two complementary parts of this program will make it a long-lasting legacy of Spitzer to the fields of comparative exoplanetology and astrobiology, by providing the necessary measurements on the inner system of TRAPPIST-1 (complete census, masses, eccentricities, first insights on atmospheres) required to initiate and optimize the detailed atmospheric characterization of its different components with JWST and other future facilities.

  16. Faceted Search

    CERN Document Server

    Tunkelang, Daniel

    2009-01-01

    We live in an information age that requires us, more than ever, to represent, access, and use information. Over the last several decades, we have developed a modern science and technology for information retrieval, relentlessly pursuing the vision of a "memex" that Vannevar Bush proposed in his seminal article, "As We May Think." Faceted search plays a key role in this program. Faceted search addresses weaknesses of conventional search approaches and has emerged as a foundation for interactive information retrieval. User studies demonstrate that faceted search provides more

  17. SIM PlanetQuest: Science with the Space Interferometry Mission

    Science.gov (United States)

    Unwin, Stephen (Editor); Turyshev, Slava (Editor)

    2004-01-01

    SIM - the Space Interferometry Mission - will perform precision optical astrometry on objects as faint as R magnitude 20. It will be the first space-based astrometric interferometer, operating in the optical band with a 10-m baseline. The Project is managed by the Jet Propulsion Laboratory, California Institute of Technology, in close collaboration with two industry partners, Lockheed Martin Missiles and Space, and TRW Inc., Space and Electronics Group. Launch of SIM is currently planned for 2009. In its wide-angle astrometric mode, SIM will yield 4 microarcsecond absolute position and parallax measurements. Astrometric planet searches will be done in a narrow-angle mode, with an accuracy of 4 microarcseconds or better in a single measurement. As a pointed rather than a survey instrument, SIM will maintain.its astrometric accuracy down to the faintest, magnitudes, opening up the opportunity for astrometry of active galactic nuclei to better than 10 pas. SIM will define a new astrometric reference frame, using a grid of approximately 1500 stars with positions accurate to 4 microarcseconds. The SIM Science Team comprises the Principal Investigators of ten Key Projects, and five Mission Scientists contributing their expertise to specific areas of the mission. Their science programs cover a wide range of topics in Galactic and extragalactic astronomy. They include: searches for low-mass planets - including analogs to our own solar system - tlie formation and dynamics of our Galaxy, calibration of the cosmic distance scale, and fundamental stellar astrophysics. All of the science observing on SIM is competitively awarded; the Science Team programs total about 40% of the total available, and the remainder will be assigned via future NASA competitions. This report is a compilation of science summaries by members of the Science Team, and it illustrates the wealth of scientific problems that microarcsecond-precision astrometry can contribute to. More information on SIM

  18. Terrestrial Planet Occurrence Rates for the Kepler GK Dwarf Sample

    CERN Document Server

    Burke, Christopher J; Mullally, F; Seader, Shawn; Huber, Daniel; Rowe, Jason F; Coughlin, Jeffrey L; Thompson, Susan E; Catanzarite, Joseph; Clarke, Bruce D; Morton, Timothy D; Caldwell, Douglas A; Bryson, Stephen T; Haas, Michael R; Batalha, Natalie M; Jenkins, Jon M; Tenenbaum, Peter; Twicken, Joseph D; Li, Jie; Quintana, Elisa; Barclay, Thomas; Henze, Christopher E; Borucki, William J; Howell, Steve B; Still, Martin

    2015-01-01

    We measure planet occurrence rates using the planet candidates discovered by the Q1-Q16 Kepler pipeline search. This study examines planet occurrence rates for the Kepler GK dwarf target sample for planet radii, 0.75planets per star, with an allowed range of 0.3planet occurrence rates and a steeper increase in planet occurrence rates towards small planets than previous studies of the Kepler GK dwarf sample. Through extrapolation, we find that the one year orbital period terrestrial planet occurrence rate, zeta_1=0.1, with an allowed r...

  19. The Search for Another Earth

    Indian Academy of Sciences (India)

    2016-07-01

    Is there life anywhere else in the vast cosmos?Are there planets similar to the Earth? For centuries,these questions baffled curious minds. Eithera positive or negative answer, if found oneday, would carry a deep philosophical significancefor our very existence in the universe. Althoughthe search for extra-terrestrial intelligence wasinitiated decades ago, a systematic scientific andglobal quest towards achieving a convincing answerbegan in 1995 with the discovery of the firstconfirmed planet orbiting around the solar-typestar 51 Pegasi. Since then, astronomers have discoveredmany exoplanets using two main techniques,radial velocity and transit measurements.In the first part of this article, we shall describethe different astronomical methods through whichthe extrasolar planets of various kinds are discovered.In the second part of the article we shalldiscuss the various kinds of exoplanets, in particularabout the habitable planets discovered tilldate and the present status of our search for ahabitable planet similar to the Earth.

  20. Constraint Programming based Local Search for the Vehicle Routing Problem with Time Windows

    OpenAIRE

    Sala Reixach, Joan

    2012-01-01

    El projecte es centra en el "Vehicle Routing Problem with Time Windows". Explora i testeja un mètode basat en una formulació del problema en termes de programació de restriccions. Implementa un mètode de cerca local amb la capacitat de fer grans moviments anomenat "Large Neighbourhood Search".

  1. Allocation of UAV Search Efforts Using Dynamic Programming and Bayesian Updating

    Science.gov (United States)

    2008-06-01

    develop a model for SOP and a heuristic algorithm for obtaining efficient search plans in real-time within a rolling time horizon framework. 2 The...computational effort increases exponentially. As a result, we constructed a heuristic algorithm for solving TTLP. The heuristic algorithm amounts to total

  2. NAHUAL: A cool spectrograph for planets of ultra-cool objects

    CERN Document Server

    Guenther, E W; Barrado y Navascués, D; Laux, U

    2005-01-01

    We present the status of an ongoing study to built a a high resolution near infrared Echelle spectrograph (NAHUAL) for the 10.4-m-Gran Telescopio Canarias (GTC) which will be especially optimised for planet searches by means of high precision radial velocity measurements. We show that infrared radial velocity programs are particularly suitable to search for planets very low mass stars and brown dwarfs, as well as active stars. The goal of NAHUAL is to reach an accuracy of the radial velocity measurement of a few m/s, which would allow the detection of planets with a few earth-masses orbiting low-mass stars and brown dwarfs. It is planed that NAHUAL covers simultaneously the full wavelength range in the J, H, and K-band, and will also serve as a general purpose high resolution near infrared spectrograph of the GTC. The planed instrument will have a resolution of R=50,000 with a 0.175 arcsec slit, and an AO-system. An absorption cell will serve as a simultaneous wavelength reference.

  3. MESSENGER: Exploring the Innermost Planet

    Science.gov (United States)

    Solomon, S. C.

    2011-12-01

    One of Earth's closest planetary neighbors, Mercury remained comparatively unexplored for the more than three decades that followed the three flybys of the innermost planet by the Mariner 10 spacecraft in 1974-75. Mariner 10 imaged 45% of Mercury's surface at about 1 km/pixel average resolution, confirmed Mercury's anomalously high bulk density and implied large fractional core size, discovered Mercury's internal magnetic field, documented that H and He are present in the planet's tenuous exosphere, and made the first exploration of Mercury's magnetosphere and solar wind environment. Ground-based astronomers later reported Na, K, and Ca in Mercury's exosphere; the presence of deposits in the floors of polar craters having radar characteristics best matched by water ice; and strong evidence from the planet's forced libration amplitude that Mercury has a fluid outer core. Spacecraft exploration of Mercury resumed with the selection for flight, under NASA's Discovery Program, of the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission. Launched in 2004, MESSENGER flew by the innermost planet three times in 2008-2009 en route to becoming the first spacecraft to orbit Mercury in March of this year. MESSENGER's first chemical remote sensing measurements of Mercury's surface indicate that the planet's bulk silicate fraction differs from those of the other inner planets, with a low-Fe surface composition intermediate between basalts and ultramafic rocks and best matched among terrestrial rocks by komatiites. Moreover, surface materials are richer in the volatile constituents S and K than predicted by most planetary formation models. Global image mosaics and targeted high-resolution images (to resolutions of 10 m/pixel) reveal that Mercury experienced globally extensive volcanism, including large expanses of plains emplaced as flood lavas and widespread examples of pyroclastic deposits likely emplaced during explosive eruptions of volatile

  4. The Atmospheres of Extrasolar Planets

    Science.gov (United States)

    Richardson, L. J.; Seager, S.

    2007-01-01

    In this chapter we examine what can be learned about extrasolar planet atmospheres by concentrating on a class of planets that transit their parent stars. As discussed in the previous chapter, one way of detecting an extrasolar planet is by observing the drop in stellar intensity as the planet passes in front of the star. A transit represents a special case in which the geometry of the planetary system is such that the planet s orbit is nearly edge-on as seen from Earth. As we will explore, the transiting planets provide opportunities for detailed follow-up observations that allow physical characterization of extrasolar planets, probing their bulk compositions and atmospheres.

  5. New worlds on the horizon: Earth-sized planets close to other stars.

    Science.gov (United States)

    Gaidos, Eric; Haghighipour, Nader; Agol, Eric; Latham, David; Raymond, Sean; Rayner, John

    2007-10-12

    The search for habitable planets like Earth around other stars fulfills an ancient imperative to understand our origins and place in the cosmos. The past decade has seen the discovery of hundreds of planets, but nearly all are gas giants like Jupiter and Saturn. Recent advances in instrumentation and new missions are extending searches to planets the size of Earth but closer to their host stars. There are several possible ways such planets could form, and future observations will soon test those theories. Many of these planets we discover may be quite unlike Earth in their surface temperature and composition, but their study will nonetheless inform us about the process of planet formation and the frequency of Earth-like planets around other stars.

  6. New Worlds on the Horizon: Earth-Sized Planets Close to Other Stars

    CERN Document Server

    Gaidos, Eric; Agol, Eric; Latham, David; Raymond, Sean; Rayner, John

    2007-01-01

    The search for habitable planets like Earth around other stars fulfils an ancient imperative to understand our origins and place in the cosmos. The past decade has seen the discovery of hundreds of planets, but nearly all are gas giants like Jupiter and Saturn. Recent advances in instrumentation and new missions are extending searches to planets the size of the Earth, but closer to their host stars. There are several possible ways such planets could form, and future observations will soon test those theories. Many of these planets we discover may be quite unlike Earth in their surface temperature and composition, but their study will nonetheless inform us about the process of planet formation and the frequency of Earth-like planets around other stars.

  7. New Worlds on the Horizon: Earth-Sized Planets Close to Other Stars

    Science.gov (United States)

    Gaidos, Eric; Haghighipour, Nader; Agol, Eric; Latham, David; Raymond, Sean; Rayner, John

    2007-10-01

    The search for habitable planets like Earth around other stars fulfills an ancient imperative to understand our origins and place in the cosmos. The past decade has seen the discovery of hundreds of planets, but nearly all are gas giants like Jupiter and Saturn. Recent advances in instrumentation and new missions are extending searches to planets the size of Earth but closer to their host stars. There are several possible ways such planets could form, and future observations will soon test those theories. Many of these planets we discover may be quite unlike Earth in their surface temperature and composition, but their study will nonetheless inform us about the process of planet formation and the frequency of Earth-like planets around other stars.

  8. Looking for Very Short-Period Planets with Re-Purposed Kepler

    CERN Document Server

    Jackson, Brian

    2013-01-01

    A re-purposed Kepler mission could continue the search for nearly Earth-sized planets in very short-period (< 1 day) orbits. Recent surveys of the Kepler data already available have revealed at least a dozen such planetary candidates, and a more complete and focused survey is likely to reveal more. Given the planets' short orbital periods, building the requisite signal-to-noise to detect the candidates by stacking multiple transits requires a much shorter observational baseline than for longer-period planets, and the transits are likely more robust against the much larger instrumental variations anticipated for the modified Kepler pointing capabilities. Searching for these unusual planets will also leverage the Kepler mission's already considerable expertise in planetary transit detection and analysis. These candidates may represent an entirely new class of planet. They may also provide unprecedented insights into planet formation and evolution and sensitive probes for planet-star interactions and the stel...

  9. Astrometry and radial velocities of the planet host M dwarf GJ 317: new trigonometric distance, metallicity and upper limit to the mass of GJ 317b

    CERN Document Server

    Anglada-Escudé, Guillem; Weinberger, Alycia J; Thompson, Ian B; Butler, R Paul; Vogt, Steven S; Rivera, Eugenio J

    2011-01-01

    We have obtained precision astrometry of the planet hosting M dwarf GJ 317 in the framework of the Carnegie Astrometric Planet Search project. The new astrometric measurements give a distance determination of 15.3 pc, 65% further than previous estimates. The resulting absolute magnitudes suggest it is metal rich and more massive than previously assumed. This result strengthens the correlation between high metallicity and the presence of gas giants around low mass stars. At 15.3 pc, the minimal astrometric amplitude for planet candidate GJ 317b is 0.3 milliarcseconds (edge-on orbit), just below our astrometric sensitivity. However, given the relatively large number of observations and good astrometric precision, a Bayesian Monte Carlo Markov Chain analysis indicates that the mass of planet b has to be smaller than twice the minimum mass with a 99% confidence level, with a most likely value of 2.5 Mjup. Additional RV measurements obtained with Keck by the Lick-Carnegie Planet search program confirm the presence...

  10. Reinflating Giant Planets

    Science.gov (United States)

    Kohler, Susanna

    2017-01-01

    Two new, large gas-giant exoplanets have been discovered orbiting close to their host stars. A recent study examining these planets and others like them may help us to better understand what happens to close-in hot Jupiters as their host stars reach the end of their main-sequence lives.OversizedGiantsUnbinned transit light curves for HAT-P-65b. [Adapted from Hartman et al. 2016]The discovery of HAT-P-65b and HAT-P-66b, two new transiting hot Jupiters, is intriguing. These planets have periods of just under 3 days and masses of roughly 0.5 and 0.8 times that of Jupiter, but their sizes are whats really interesting: they have inflated radii of 1.89 and 1.59 times that of Jupiter.These two planets, discovered using the Hungarian-made Automated Telescope Network (HATNet) in Arizona and Hawaii, mark the latest in an ever-growing sample of gas-giant exoplanets with radii larger than expected based on theoretical planetary structure models.What causes this discrepancy? Did the planets just fail to contract to the expected size when they were initially formed, or were they reinflated later in their lifetimes? If the latter, how? These are questions that scientists are only now starting to be able to address using statistics of the sample of close-in, transiting planets.Unbinned transit light curves for HAT-P-66b. [Hartman et al. 2016]Exploring Other PlanetsLed by Joel Hartman (Princeton University), the team that discovered HAT-P-65b and HAT-P-66b has examined these planets observed parameters and those of dozens of other known close-in, transiting exoplanets discovered with a variety of transiting exoplanet missions: HAT, WASP, Kepler, TrES, and KELT. Hartman and collaborators used this sample to draw conclusions about what causes some of these planets to have such large radii.The team found that there is a statistically significant correlation between the radii of close-in giant planets and the fractional ages of their host stars (i.e., the stars age divided by its full

  11. Forthcoming mutual events of planets and astrometric radio sources

    CERN Document Server

    Malkin, Z; Tsekmejster, S

    2013-01-01

    Radio astronomy observations of close approaches of the Solar system planets to compact radio sources as well as radio source occultations by planets may be of large interest for planetary sciences, dynamical astronomy, and testing gravity theories. In this paper, we present extended lists of occultations of astrometric radio sources observed in the framework of various astrometric and geodetic VLBI programs by planets, and close approaches of planets to radio sources expected in the nearest years. Computations are made making use of the EPOS software package.

  12. Dysonian SETI as a "Shortcut" to Detecting Habitable Planets

    Science.gov (United States)

    Wright, J. T.

    2016-12-01

    The search for habitable planets is ultimately motivated by the search for inhabited planets. On Earth, the most telling signature of life is that of humanity's technology. The Search for Extraterrestrial Intelligence (SETI) is thus the "ultimate" search for habitable planets.In 1960 two seminal papers in SETI were published, providing two visions for SETI. Giuseppe Cocconi and Philip Morrison's proposed detecting deliberate radio signals ("communication SETI"), while Freeman Dyson ("artifact SETI"), proposed detecting the inevitable effects of massive energy supplies and artifacts on their surroundings. While communication SETI has now had many career-long practitioners and major efforts, artifact SETI has, until recently, not been a vibrant field of study. The launch of the Kepler and WISE satellites have greatly renewed interest in the field, however, and the recent Breakthrough Listen Initiative has provided new motivation for finding good targets for communication SETI. I will discuss the progress of the Ĝ Search for Extraterrestrial Civilizations with Large Energy Supplies, including its justification and motivation, waste heat search strategy and first results, and the framework for a search for megastructures via transit light curves. The last of these led to the identification of KIC 8462852 (a.k.a. "Tabby's Star") as a candidate ETI host. This star, discovered by Boyajian and the Zooniverse Planet Hunters, exhibits several apparently unique and so-far unexplained photometric properties, and continues to confound natural explanation.

  13. Extrasolar binary planets. I. Formation by tidal capture during planet-planet scattering

    Energy Technology Data Exchange (ETDEWEB)

    Ochiai, H. [Earth and Planetary Sciences, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551 (Japan); Nagasawa, M. [Interactive Research Center of Science, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8551 (Japan); Ida, S., E-mail: nagasawa.m.ad@m.titech.ac.jp [Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)

    2014-08-01

    We have investigated (1) the formation of gravitationally bounded pairs of gas-giant planets (which we call 'binary planets') from capturing each other through planet-planet dynamical tide during their close encounters and (2) the subsequent long-term orbital evolution due to planet-planet and planet-star quasi-static tides. For the initial evolution in phase 1, we carried out N-body simulations of the systems consisting of three Jupiter-mass planets taking into account the dynamical tide. The formation rate of the binary planets is as much as 10% of the systems that undergo orbital crossing, and this fraction is almost independent of the initial stellarcentric semimajor axes of the planets, while ejection and merging rates sensitively depend on the semimajor axes. As a result of circularization by the planet-planet dynamical tide, typical binary separations are a few times the sum of the physical radii of the planets. After the orbital circularization, the evolution of the binary system is governed by long-term quasi-static tide. We analytically calculated the quasi-static tidal evolution in phase 2. The binary planets first enter the spin-orbit synchronous state by the planet-planet tide. The planet-star tide removes angular momentum of the binary motion, eventually resulting in a collision between the planets. However, we found that the binary planets survive the tidal decay for the main-sequence lifetime of solar-type stars (∼10 Gyr), if the binary planets are beyond ∼0.3 AU from the central stars. These results suggest that the binary planets can be detected by transit observations at ≳ 0.3 AU.

  14. A Direct Path to Finding Earth-Like Planets

    Science.gov (United States)

    Heap, Sara R.; Linder, Don J.

    2009-01-01

    As envisaged by the 2000 astrophysics decadal survey panel: The main goal of Terrestrial Planet Finder (TPF) is nothing less than to search for evidence of life on terrestrial planets around nearby stars . Here, we consider how an optical telescope paired with a free-flying occulter blocking light from the star can reach this goal directly, without knowledge of results from prior astrometric, doppler, or transit exoplanet observations. Using design reference missions and other simulations, we explore the potential of TPF-O to find planets in the habitable zone around their central stars, to spectrally characterize the atmospheres of detected planets, and to obtain rudimentary information about their orbits. We emphasize the importance of ozone absorption in the UV spectrum of a planet as a marker of photosynthesis by plants, algae, and cyanobacteria.

  15. A Direct Path to Finding Earth-Like Planets

    Science.gov (United States)

    Heap, Sara R.; Linder, Don J.

    2009-01-01

    As envisaged by the 2000 astrophysics decadal survey panel: The main goal of Terrestrial Planet Finder (TPF) is nothing less than to search for evidence of life on terrestrial planets around nearby stars . Here, we consider how an optical telescope paired with a free-flying occulter blocking light from the star can reach this goal directly, without knowledge of results from prior astrometric, doppler, or transit exoplanet observations. Using design reference missions and other simulations, we explore the potential of TPF-O to find planets in the habitable zone around their central stars, to spectrally characterize the atmospheres of detected planets, and to obtain rudimentary information about their orbits. We emphasize the importance of ozone absorption in the UV spectrum of a planet as a marker of photosynthesis by plants, algae, and cyanobacteria.

  16. Protostars and Planets VI

    Science.gov (United States)

    Beuther, Henrik; Klessen, Ralf S.; Dullemond, Cornelis P.; Henning, Thomas

    The Protostars and Planets book and conference series has been a long-standing tradition that commenced with the first meeting led by Tom Gehrels and held in Tucson, Arizona, in 1978. The goal then, as it still is today, was to bridge the gap between the fields of star and planet formation as well as the investigation of planetary systems and planets. As Tom Gehrels stated in the preface to the first Protostars and Planets book, "Cross-fertilization of information and understanding is bound to occur when investigators who are familiar with the stellar and interstellar phases meet with those who study the early phases of solar system formation." The central goal remained the same for the subsequent editions of the books and conferences Protostars and Planets II in 1984, Protostars and Planets III in 1990, Protostars and Planets IV in 1998, and Protostars and Planets V in 2005, but has now been greatly expanded by the flood of new discoveries in the field of exoplanet science. The original concept of the Protostars and Planets series also formed the basis for the sixth conference in the series, which took place on July 15-20, 2013. It was held for the first time outside of the United States in the bustling university town of Heidelberg, Germany. The meeting attracted 852 participants from 32 countries, and was centered around 38 review talks and more than 600 posters. The review talks were expanded to form the 38 chapters of this book, written by a total of 250 contributing authors. This Protostars and Planets volume reflects the current state-of-the-art in star and planet formation, and tightly connects the fields with each other. It is structured into four sections covering key aspects of molecular cloud and star formation, disk formation and evolution, planetary systems, and astrophysical conditions for life. All poster presentations from the conference can be found at www.ppvi.org. In the eight years that have passed since the fifth conference and book in the

  17. Almost All of Kepler's Multiple Planet Candidates are Planets

    CERN Document Server

    Lissauer, Jack J; Rowe, Jason F; Bryson, Stephen T; Adams, Elisabeth; Buchhave, Lars A; Ciardi, David R; Cochran, William D; Fabrycky, Daniel C; Ford, Eric B; Fressin, Francois; Geary, John; Gilliland, Ronald L; Holman, Matthew J; Howell, Steve B; Jenkins, Jon M; Kinemuchi, Karen; Koch, David G; Morehead, Robert C; Ragozzine, Darin; Seader, Shawn E; Tanenbaum, Peter G; Torres, Guillermo; Twicken, Joseph D

    2012-01-01

    We present a statistical analysis that demonstrates that the overwhelming majority of Kepler candidate multiple transiting systems (multis) indeed represent true, physically-associated transiting planets. Binary stars provide the primary source of false positives among Kepler planet candidates, implying that false positives should be nearly randomly-distributed among Kepler targets. In contrast, true transiting planets would appear clustered around a smaller number of Kepler targets if detectable planets tend to come in systems and/or if the orbital planes of planets encircling the same star are correlated. There are more than one hundred times as many Kepler planet candidates in multi-candidate systems as would be predicted from a random distribution of candidates, implying that the vast majority are true planets. Most of these multis are multiple planet systems orbiting the Kepler target star, but there are likely cases where (a) the planetary system orbits a fainter star, and the planets are thus significa...

  18. Limits on the Abundance of Galactic Planets From Five Years of PLANET Observations

    CERN Document Server

    Albrow, M D; Beaulieu, J P; Caldwell, J A R; De Poy, D L; Dominik, M; Gaudi, B S; Gould, A; Greenhill, J; Hill, K; Kane, S; Martin, R D; Menzies, J; Naber, R M; Pel, J W; Pogge, R W; Pollard, K R; Sackett, P D; Sahu, K C; Vermaak, P; Vreeswijk, P M; Watson, R; Williams, A

    2001-01-01

    We search for signatures of planets in 43 intensively monitored microlensing events that were observed between 1995 and 1999. Planets would be expected to cause a short (~1 day) deviation on an otherwise normal smooth, symmetric, single-lens light curve. We find no such anomalies and infer that less than 1/3 of the ~0.3 M_sun stars that typically comprise the lens population have Jupiter-mass companions in the range of semi-major axes 1.5 AU < a < 4 AU.

  19. An inertia-free filter line-search algorithm for large-scale nonlinear programming

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Nai-Yuan; Zavala, Victor M.

    2016-02-15

    We present a filter line-search algorithm that does not require inertia information of the linear system. This feature enables the use of a wide range of linear algebra strategies and libraries, which is essential to tackle large-scale problems on modern computing architectures. The proposed approach performs curvature tests along the search step to detect negative curvature and to trigger convexification. We prove that the approach is globally convergent and we implement the approach within a parallel interior-point framework to solve large-scale and highly nonlinear problems. Our numerical tests demonstrate that the inertia-free approach is as efficient as inertia detection via symmetric indefinite factorizations. We also demonstrate that the inertia-free approach can lead to reductions in solution time because it reduces the amount of convexification needed.

  20. Hidden Treasure; Parents Search for Quality in Programs for Infants and Toddlers.

    Science.gov (United States)

    Mazyck, Aurelia; And Others

    The things that one can see in a child care program that identify it as a good program for babies and their families are described. The two main questions that are answered are: What is quality in an arrangement for infant care? and How is a parent to recognize it when it is found. The topics discussed are: (1) Involvement with Parents, Home, and…

  1. A Search for Sources of Treatment Effects in a Teacher Effectiveness Training Program.

    Science.gov (United States)

    Harris, Alene Hawes

    This study investigated possible sources of teacher change in the Stallings Effective Use of time (EUOT) staff development program administered to preservice teachers. These sources were: (1) the full EUOT program with feedback plus workshops; (2) feedback only; and (3) the trainer as post-treatment observer. Over a 15-month period, 20 student…

  2. 75 FR 67705 - Office of Postsecondary Education; Overview Information; Talent Search (TS) Program; Notice...

    Science.gov (United States)

    2010-11-03

    ... rigorous secondary school program of study, postsecondary education enrollment, and postsecondary degree... individuals with potential for education at the postsecondary level and encourage them to complete secondary school and undertake a program of postsecondary education. TS projects publicize the availability of,...

  3. Influence of Stellar Multiplicity On Planet Formation. IV. Adaptive Optics Imaging of Kepler Stars With Multiple Transiting Planet Candidates

    CERN Document Server

    Wang, Ji; Xie, Ji-Wei; Ciardi, David R

    2015-01-01

    The Kepler mission provides a wealth of multiple transiting planet systems (MTPS). The formation and evolution of multi-planet systems are likely to be influenced by companion stars given the abundance of multi stellar systems. We study the influence of stellar companions by measuring the stellar multiplicity rate of MTPS. We select 138 bright (KP < 13.5) Kepler MTPS and search for stellar companions with AO imaging data and archival radial velocity (RV) data. We obtain new AO images for 73 MTPS. Other MTPS in the sample have archival AO imaging data from the Kepler Community Follow-up Observation Program (CFOP). From these imaging data, we detect 42 stellar companions around 35 host stars. For stellar separation 1 AU < a < 100 AU, the stellar multiplicity rate is 5.2 $\\pm$ 5.0% for MTPS, which is 2.8{\\sigma} lower than 21.1 $\\pm$ 2.8% for the control sample, i.e., the field stars in the solar neighborhood. We identify two origins for the deficit of stellar companions within 100 AU to MTPS: (1) a sup...

  4. Finding Planets Orbiting Bright Stars with SuperWASP-South

    Science.gov (United States)

    Turner, O.; Anderson, D. R.; Maxted, P. L. F.; Hellier, C.

    2015-10-01

    Over the past decade the Wide Angle Search for Planets(WASP) project has been at the forefront of the ground-based hunt for transiting planets. In that time, WASP has found many systems that push the boundaries of our understanding of planet formation and evolution. In recent years both the North and South installations have changed their observing strategies with the aim of discovering rarer objects to further fill gaps in our knowledge and test current theory. Here we look at the performance and potential of the new WASP-South instrument, which we modified to target brighter stars. We also present some new discoveries from this brighter, southern campaign.

  5. Planets Transiting Bright Stars with WASP-South

    Science.gov (United States)

    Turner, O. D.; Anderson, D. R.; Hellier, C.; Maxted, P. F. L.

    2015-10-01

    Over the past decade the Wide Angle Search for Planets (WASP) project has been at the forefront of the ground-based hunt for transiting planets. In that time, WASP has found many systems that push the boundaries of our understanding of planet formation and evolution. In recent years both the North and South installations have changed their observing strategies with the aim of discovering rarer objects to further fill gaps in our knowledge and test current theory. Here we look at the performance and potential of the new WASP-South instrument, which we modified to target brighter stars. We also present some new discoveries from this brighter, southern campaign.

  6. Planet Hunters 2 in the K2 Era

    Science.gov (United States)

    Schwamb, Megan E.; Fischer, Debra; Boyajian, Tabetha S.; Giguere, Matthew J.; Ishikawa, Sascha; Lintott, Chris; Lynn, Stuart; Schmitt, Joseph; Snyder, Chris; Wang, Ji; Barclay, Thomas

    2015-01-01

    Planet Hunters (http://www.planethunters.org) is an online citizen science project enlisting hundreds of thousands of people to search for planet transits in the publicly released Kepler data. Volunteers mark the locations of visible transits in a web interface, with multiple independent classifiers reviewing a randomly selected ~30-day light curve segment. In September 2014, Planet Hunters entered a new phase. The project was relaunched with a brand new online classification interface and discussion tool built using the Zooniverse's (http://www.zooniverse.org) latest technology and web platform. The website has been optimized for the rapid discovery and identification of planet candidates in the light curves from K2, the two-wheeled ecliptic plane Kepler mission. We will give an overview of the new Planet Hunters classification interface and Round 2 review system in context of the K2 data. We will present the first results from the Planet Hunters 2 search of K2 Campaigns 0 and 1 including a summary of new planet candidates.

  7. SEARCH: Study of Environmental Arctic Change--A System-scale, Cross-disciplinary Arctic Research Program

    Science.gov (United States)

    Shnoro, R. S.; Eicken, H.; Francis, J. A.; Scambos, T. A.; Schuur, E. A.; Straneo, F.; Wiggins, H. V.

    2013-12-01

    SEARCH is an interdisciplinary, interagency program that works with academic and government agency scientists and stakeholders to plan, conduct, and synthesize studies of Arctic change. Over the past three years, SEARCH has developed a new vision and mission, a set of prioritized cross-disciplinary 5-year goals, an integrated set of activities, and an organizational structure. The vision of SEARCH is to provide scientific understanding of arctic environmental change to help society understand and respond to a rapidly changing Arctic. SEARCH's 5-year science goals include: 1. Improve understanding, advance prediction, and explore consequences of changing Arctic sea ice. 2. Document and understand how degradation of near-surface permafrost will affect Arctic and global systems. 3. Improve predictions of future land-ice loss and impacts on sea level. 4. Analyze societal and policy implications of Arctic environmental change. Action Teams organized around each of the 5-year goals will serve as standing groups responsible for implementing specific goal activities. Members will be drawn from academia, different agencies and stakeholders, with a range of disciplinary backgrounds and perspectives. 'Arctic Futures 2050' scenarios tasks will describe plausible future states of the arctic system based on recent trajectories and projected changes. These scenarios will combine a range of data including climate model output, paleo-data, results from data synthesis and systems modeling, as well as expert scientific and traditional knowledge. Current activities include: - Arctic Observing Network (AON) - coordinating a system of atmospheric, land- and ocean-based environmental monitoring capabilities that will significantly advance our observations of arctic environmental conditions. - Arctic Sea Ice Outlook - an international effort that provides monthly summer reports synthesizing community estimates of the expected sea ice minimum. A newly-launched Sea Ice Prediction Network

  8. Imaging Extrasolar Giant Planets

    Science.gov (United States)

    Bowler, Brendan P.

    2016-10-01

    High-contrast adaptive optics (AO) imaging is a powerful technique to probe the architectures of planetary systems from the outside-in and survey the atmospheres of self-luminous giant planets. Direct imaging has rapidly matured over the past decade and especially the last few years with the advent of high-order AO systems, dedicated planet-finding instruments with specialized coronagraphs, and innovative observing and post-processing strategies to suppress speckle noise. This review summarizes recent progress in high-contrast imaging with particular emphasis on observational results, discoveries near and below the deuterium-burning limit, and a practical overview of large-scale surveys and dedicated instruments. I conclude with a statistical meta-analysis of deep imaging surveys in the literature. Based on observations of 384 unique and single young (≈5-300 Myr) stars spanning stellar masses between 0.1 and 3.0 M ⊙, the overall occurrence rate of 5-13 M Jup companions at orbital distances of 30-300 au is {0.6}-0.5+0.7 % assuming hot-start evolutionary models. The most massive giant planets regularly accessible to direct imaging are about as rare as hot Jupiters are around Sun-like stars. Dividing this sample into individual stellar mass bins does not reveal any statistically significant trend in planet frequency with host mass: giant planets are found around {2.8}-2.3+3.7 % of BA stars, planets spanning a broad range of masses and ages.

  9. Extrasolar planet interactions

    Science.gov (United States)

    Barnes, Rory; Greenberg, Richard

    2008-05-01

    The dynamical interactions of planetary systems may be a clue to their formation histories. Therefore, the distribution of these interactions provides important constraints on models of planet formation. We focus on each system's apsidal motion and proximity to dynamical instability. Although only 25 multiple planet systems have been discovered to date, our analyses in these terms have revealed several important features of planetary interactions. 1) Many systems interact such that they are near the boundary between stability and instability. 2) Planets tend to form such that at least one planet's eccentricity periodically drops to near zero. 3) Mean-motion resonant pairs would be unstable if not for the resonance. 4) Scattering of approximately equal mass planets is unlikely to produce the observed distribution of apsidal behavior. 5) Resonant interactions may be identified through calculating a system's proximity to instability, regardless of knowledge of angles such as mean longitude and longitude of periastron (e.g. GJ 317 b and c are probably in a 4:1 resonance). These properties of planetary systems have been identified through calculation of two parameters that describe the interaction. The apsidal interaction can be quantified by determining how close a planet is to an apsidal separatrix (a boundary between qualitatively different types of apsidal oscillations, e.g. libration or circulation of the major axes). This value can be calculated through short numerical integrations. The proximity to instability can be measured by comparing the observed orbital elements to an analytic boundary that describes a type of stability known as Hill stability. We have set up a website dedicated to presenting the most up-to-date information on dynamical interactions: http://www.lpl.arizona.edu/~rory/research/xsp/dynamics.

  10. Heat Pipe Planets

    Science.gov (United States)

    Moore, William B.; Simon, Justin I.; Webb, A. Alexander G.

    2014-01-01

    When volcanism dominates heat transport, a terrestrial body enters a heat-pipe mode, in which hot magma moves through the lithosphere in narrow channels. Even at high heat flow, a heat-pipe planet develops a thick, cold, downwards-advecting lithosphere dominated by (ultra-)mafic flows and contractional deformation at the surface. Heat-pipes are an important feature of terrestrial planets at high heat flow, as illustrated by Io. Evidence for their operation early in Earth's history suggests that all terrestrial bodies should experience an episode of heat-pipe cooling early in their histories.

  11. Developments in Planet Detection using Transit Timing Variations

    Energy Technology Data Exchange (ETDEWEB)

    Steffen, Jason H.; /Fermilab; Agol, Eric; /Washington U., Seattle, Astron. Dept.

    2006-12-01

    In a transiting planetary system, the presence of a second planet will cause the time interval between transits to vary. These transit timing variations (TTV) are particularly large near mean-motion resonances and can be used to infer the orbital elements of planets with masses that are too small to detect by any other means. The author presents the results of a study of simulated data where they show the potential that this planet detection technique has to detect and characterize secondary planets in transiting systems. These results have important ramifications for planetary transit searches since each transiting system presents an opportunity for additional discoveries through a TTV analysis. They present such an analysis for 13 transits of the HD 209458 system that were observed with the Hubble Space Telescope. This analysis indicates that a putative companion in a low-order, mean-motion resonance can be no larger than the mass of the Earth and constitutes, to date, the most sensitive probe for extrasolar planets that orbit main sequence stars. The presence or absence of small planets in low-order, mean-motion resonances has implications for theories of the formation and evolution of planetary systems. Since TTV is most sensitive in these regimes, it should prove a valuable tool not only for the detection of additional planets in transiting systems, but also as a way to determine the dominant mechanisms of planet formation and the evolution of planetary systems.

  12. International Conference and Advanced School Planet Earth

    CERN Document Server

    Jeltsch, Rolf; Pinto, Alberto; Viana, Marcelo

    2015-01-01

    The focus of this volume is research carried out as part of the program Mathematics of Planet Earth, which provides a platform to showcase the essential role of mathematics in addressing planetary problems and creating a context for mathematicians and applied scientists to foster mathematical and interdisciplinary developments that will be necessary to tackle a myriad of issues and meet future global challenges. Earth is a planet with dynamic processes in its mantle, oceans and atmosphere creating climate, causing natural disasters, and influencing fundamental aspects of life and life-supporting systems. In addition to these natural processes, human activity has increased to the point where it influences the global climate, impacts the ability of the planet to feed itself and threatens the stability of these systems. Issues such as climate change, sustainability, man-made disasters, control of diseases and epidemics, management of resources, risk analysis, and global integration have come to the fore. Written...

  13. A Scientometric Prediction of the Discovery of the First Potentially Habitable Planet with a Mass Similar to Earth

    CERN Document Server

    Arbesman, Samuel

    2010-01-01

    The search for a habitable extrasolar planet has long interested scientists, but only recently have the tools become available to search for such planets. In the past decades, the number of known extrasolar planets has ballooned into the hundreds, and with it the expectation that the discovery of the first Earth-like extrasolar planet is not far off. Here we develop a novel metric of habitability for discovered planets, and use this to arrive at a prediction for when the first habitable planet will be discovered. Using a bootstrap analysis of currently discovered exoplanets, we predict the discovery of the first Earth-like planet to be announced in the first half of 2011, with the likeliest date being early May 2011. Our predictions, using only the properties of previously discovered exoplanets, accord well with external estimates for the discovery of the first potentially habitable extrasolar planet, and highlights the the usefulness of predictive scientometric techniques to understand the pace of scientific...

  14. Twist planet drive

    Science.gov (United States)

    Vranish, John M. (Inventor)

    1996-01-01

    A planetary gear system includes a sun gear coupled to an annular ring gear through a plurality of twist-planet gears, a speeder gear, and a ground structure having an internal ring gear. Each planet gear includes a solid gear having a first half portion in the form of a spur gear which includes vertical gear teeth and a second half portion in the form of a spur gear which includes helical gear teeth that are offset from the vertical gear teeth and which contact helical gear teeth on the speeder gear and helical gear teeth on the outer ring gear. One half of the twist planet gears are preloaded downward, while the other half are preloaded upwards, each one alternating with the other so that each one twists in a motion opposite to its neighbor when rotated until each planet gear seats against the sun gear, the outer ring gear, the speeder gear, and the inner ring gear. The resulting configuration is an improved stiff anti-backlash gear system.

  15. THE ALGORITHM AND PROGRAM OF M-MATRICES SEARCH AND STUDY

    Directory of Open Access Journals (Sweden)

    Y. N. Balonin

    2013-05-01

    Full Text Available The algorithm and software for search and study of orthogonal bases matrices – minimax matrices (M-matrix are considered. The algorithm scheme is shown, comments on calculation blocks are given, and interface of the MMatrix software system developed with participation of the authors is explained. The results of the universal algorithm work are presented as Hadamard matrices, Belevitch matrices (C-matrices, conference matrices and matrices of even and odd orders complementary and closely related to those ones by their properties, in particular, the matrix of the 22-th order for which there is no C-matrix. Examples of portraits for alternative matrices of the 255-th and the 257-th orders are given corresponding to the sequences of Mersenne and Fermat numbers. A new way to get Hadamard matrices is explained, different from the previously known procedures based on iterative processes and calculations of Lagrange symbols, with theoretical and practical meaning.

  16. BUILDING ON THE MARS PLANET

    National Research Council Canada - National Science Library

    Valeriy Pershakov; Tatyana Petrova

    2012-01-01

    The main task is the terraforming of the Mars planet. Nowadays it is a very important task, because there are a lot of problems on the planet Earth, which deals with the exhaustion of natural resources...

  17. Searching for the Core of Journalism Education: Program Directors Disagree on Curriculum Priorities

    Science.gov (United States)

    Blom, Robin; Davenport, Lucinda D.

    2012-01-01

    To carry out their mission of preparing students to be successful journalism professionals, educators make important decisions on the core curriculum: the common courses that all journalism students must take to graduate, no matter their area of emphasis or academic constraints. This national study of U.S. journalism program directors shows they…

  18. Professional Development to Work with Low-Educated Adult ESL Learners: Searching beyond the Program

    Science.gov (United States)

    McCluskey, Corrie

    2012-01-01

    After following career interests that included anthropology and the visual arts, the author realized that working with adult immigrants with limited formal education and literacy skills was her path and her passion. Since few programs in the TESOL field focused on these learners, the author sought out instruction in nontraditional spaces to…

  19. A Search for Identity: Exploring Core Competencies for Interdisciplinary Environmental Programs

    Science.gov (United States)

    Vincent, Shirley Gayle

    2010-01-01

    Scope and method of study: The study is national in scope, exploratory, and utilized a combination of qualitative and quantitative social science methods. Findings and conclusions: Interdisciplinary environmental (IE) programs in higher education in the United States are both diverse and dynamic in their curriculum designs. Though these…

  20. Terrestrial Planets Accreted Dry

    Science.gov (United States)

    Albarede, F.; Blichert-Toft, J.

    2007-12-01

    Plate tectonics shaped the Earth, whereas the Moon is a dry and inactive desert. Mars probably came to rest within the first billion years of its history, and Venus, although internally very active, has a dry inferno for its surface. The strong gravity field of a large planet allows for an enormous amount of gravitational energy to be released, causing the outer part of the planetary body to melt (magma ocean), helps retain water on the planet, and increases the pressure gradient. The weak gravity field and anhydrous conditions prevailing on the Moon stabilized, on top of its magma ocean, a thick buoyant plagioclase lithosphere, which insulated the molten interior. On Earth, the buoyant hydrous phases (serpentines) produced by reactions between the terrestrial magma ocean and the wet impactors received from the outer Solar System isolated the magma and kept it molten for some few tens of million years. The elemental distributions and the range of condensation temperatures show that the planets from the inner Solar System accreted dry. The interior of planets that lost up to 95% of their K cannot contain much water. Foundering of their wet surface material softened the terrestrial mantle and set the scene for the onset of plate tectonics. This very same process may have removed all the water from the surface of Venus 500 My ago and added enough water to its mantle to make its internal dynamics very strong and keep the surface very young. Because of a radius smaller than that of the Earth, not enough water could be drawn into the Martian mantle before it was lost to space and Martian plate tectonics never began. The radius of a planet therefore is the key parameter controlling most of its evolutional features.

  1. Planet Hunters, Undergraduate Research, and Detection of Extrasolar Planet Kepler-818 b

    Science.gov (United States)

    Baker, David; Crannell, Graham; Duncan, James; Hays, Aryn; Hendrix, Landon

    2017-01-01

    Detection of extrasolar planets provides an excellent research opportunity for undergraduate students. In Spring 2012, we searched for transiting extrasolar planets using Kepler spacecraft data in our Research Experience in Physics course at Austin College. Offered during the regular academic year, these Research Experience courses engage students in the scientific process, including proposal writing, paper submission, peer review, and oral presentations. Since 2004, over 190 undergraduate students have conducted authentic scientific research through Research Experience courses at Austin College.Zooniverse’s citizen science Planet Hunters web site offered an efficient method for rapid analysis of Kepler data. Light curves from over 5000 stars were analyzed, of which 2.3% showed planetary candidates already tagged by the Kepler team. Another 1.5% of the light curves suggested eclipsing binary stars, and 1.6% of the light curves had simulated planets for training purposes.One of the stars with possible planetary transits had not yet been listed as a planetary candidate. We reported possible transits for Kepler ID 4282872, which later was promoted to planetary candidate KOI-1325 in 2012 and confirmed to host extrasolar planet Kepler-818 b in 2016 (Morton et al. 2016). Kepler-818 b is a “hot Neptune” with period 10.04 days, flux decrease during transit ~0.4%, planetary radius 4.69 Earth radii, and semi-major axis 0.089 au.

  2. Discovering Extrasolar Planets with Microlensing Surveys

    Science.gov (United States)

    Wambsganss, J.

    2016-06-01

    An astronomical survey is commonly understood as a mapping of a large region of the sky, either photometrically (possibly in various filters/wavelength ranges) or spectroscopically. Often, catalogs of objects are produced/provided as the main product or a by-product. However, with the advent of large CCD cameras and dedicated telescopes with wide-field imaging capabilities, it became possible in the early 1990s, to map the same region of the sky over and over again. In principle, such data sets could be combined to get very deep stacked images of the regions of interest. However, I will report on a completely different use of such repeated maps: Exploring the time domain for particular kinds of stellar variability, namely microlens-induced magnifications in search of exoplanets. Such a time-domain microlensing survey was originally proposed by Bohdan Paczynski in 1986 in order to search for dark matter objects in the Galactic halo. Only a few years later three teams started this endeavour. I will report on the history and current state of gravitational microlensing surveys. By now, routinely 100 million stars in the Galactic Bulge are monitored a few times per week by so-called survey teams. All stars with constant apparent brightness and those following known variability patterns are filtered out in order to detect the roughly 2000 microlensing events per year which are produced by stellar lenses. These microlensing events are identified "online" while still in their early phases and then monitored with much higher cadence by so-called follow-up teams. The most interesting of such events are those produced by a star-plus-planet lens. By now of order 30 exoplanets have been discovered by these combined microlensing surveys. Microlensing searches for extrasolar planets are complementary to other exoplanet search techniques. There are two particular advantages: The microlensing method is sensitive down to Earth-mass planets even with ground-based telecopes, and it

  3. Classifying Planets: Nature vs. Nurture

    Science.gov (United States)

    Beichman, Charles A.

    2009-05-01

    The idea of a planet was so simple when we learned about the solar system in elementary school. Now students and professional s alike are faced with confusing array of definitions --- from "Brown Dwarfs” to "Super Jupiters", from "Super Earths” to "Terrestrial Planets", and from "Planets” to "Small, Sort-of Round Things That Aren't Really Planets". I will discuss how planets might be defined by how they formed, where they are found, or by the life they might support.

  4. Extrasolar Binary Planets I: Formation by tidal capture during planet-planet scattering

    CERN Document Server

    Ochiai, H; Ida, S

    2014-01-01

    We have investigated i) the formation of gravitationally bounded pairs of gas-giant planets (which we call "binary planets") from capturing each other through planet-planet dynamical tide during their close encounters and ii) the following long-term orbital evolution due to planet-planet and planet-star {\\it quasi-static} tides. For the initial evolution in phase i), we carried out N-body simulations of the systems consisting of three jupiter-mass planets taking into account the dynamical tide. The formation rate of the binary planets is as much as 10% of the systems that undergo orbital crossing and this fraction is almost independent of the initial stellarcentric semi-major axes of the planets, while ejection and merging rates sensitively depend on the semi-major axes. As a result of circularization by the planet-planet dynamical tide, typical binary separations are a few times the sum of the physical radii of the planets. After the orbital circularization, the evolution of the binary system is governed by ...

  5. BUILDING ON THE MARS PLANET

    Directory of Open Access Journals (Sweden)

    Valeriy Pershakov

    2012-09-01

    Full Text Available  The main task is the terraforming of the Mars planet. Nowadays it is a very important task, because there are a lot of problems on the planet Earth, which deals with the exhaustion of natural resources. The solution is in the colonizing and building on the Mars planet.

  6. Extrasolar Planets in the Classroom

    Science.gov (United States)

    George, Samuel J.

    2011-01-01

    The field of extrasolar planets is still, in comparison with other astrophysical topics, in its infancy. There have been about 300 or so extrasolar planets detected and their detection has been accomplished by various different techniques. Here we present a simple laboratory experiment to show how planets are detected using the transit technique.…

  7. Extrasolar Planets in the Classroom

    Science.gov (United States)

    George, Samuel J.

    2011-01-01

    The field of extrasolar planets is still, in comparison with other astrophysical topics, in its infancy. There have been about 300 or so extrasolar planets detected and their detection has been accomplished by various different techniques. Here we present a simple laboratory experiment to show how planets are detected using the transit technique.…

  8. Applying what works: a systematic search of the transfer and implementation of promising Indigenous Australian health services and programs

    Directory of Open Access Journals (Sweden)

    McCalman Janya

    2012-08-01

    Full Text Available Abstract Background The transfer and implementation of acceptable and effective health services, programs and innovations across settings provides an important and potentially cost-effective strategy for reducing Indigenous Australians' high burden of disease. This study reports a systematic review of Indigenous health services, programs and innovations to examine the extent to which studies considered processes of transfer and implementation within and across Indigenous communities and healthcare settings. Methods Medline, Informit, Infotrac, Blackwells Publishing, Proquest, Taylor and Francis, JStor, and the Indigenous HealthInfoNet were searched using terms: Aborigin* OR Indigen* OR Torres AND health AND service OR program* OR intervention AND Australia to locate publications from 1992–2011. The reference lists of 19 reviews were also checked. Data from peer reviewed journals, reports, and websites were included. The 95% confidence intervals (95% CI for proportions that referred to and focussed on transfer were calculated as exact binomial confidence intervals. Test comparisons between proportions were calculated using Fisher's exact test with an alpha level of 5%. Results Of 1311 publications identified, 119 (9.1%; 95% CI: 7.6% - 10.8% referred to the transfer and implementation of Indigenous Australian health services or programs, but only 21 studies (1.6%; 95% CI: 1.0% - 2.4% actually focused on transfer and implementation. Of the 119 transfer studies, 37 (31.1%; 95% CI: 22.9 - 40.2% evaluated the impact of a service or program, 28 (23.5%; 95% CI: 16.2% - 32.2% reported only process measures and 54 were descriptive. Of the 37 impact evaluation studies, 28 (75.7%; 95% CI: 58.8% - 88.2% appeared in peer reviewed journals but none included experimental designs. Conclusion While services and programs are being transferred and implemented, few studies focus on the process by which this occurred or the effectiveness of the service or program

  9. Applying what works: a systematic search of the transfer and implementation of promising Indigenous Australian health services and programs.

    Science.gov (United States)

    McCalman, Janya; Tsey, Komla; Clifford, Anton; Earles, Wendy; Shakeshaft, Anthony; Bainbridge, Roxanne

    2012-08-03

    The transfer and implementation of acceptable and effective health services, programs and innovations across settings provides an important and potentially cost-effective strategy for reducing Indigenous Australians' high burden of disease. This study reports a systematic review of Indigenous health services, programs and innovations to examine the extent to which studies considered processes of transfer and implementation within and across Indigenous communities and healthcare settings. Medline, Informit, Infotrac, Blackwells Publishing, Proquest, Taylor and Francis, JStor, and the Indigenous HealthInfoNet were searched using terms: Aborigin* OR Indigen* OR Torres AND health AND service OR program* OR intervention AND Australia to locate publications from 1992-2011. The reference lists of 19 reviews were also checked. Data from peer reviewed journals, reports, and websites were included. The 95% confidence intervals (95% CI) for proportions that referred to and focussed on transfer were calculated as exact binomial confidence intervals. Test comparisons between proportions were calculated using Fisher's exact test with an alpha level of 5%. Of 1311 publications identified, 119 (9.1%; 95% CI: 7.6%-10.8%) referred to the transfer and implementation of Indigenous Australian health services or programs, but only 21 studies (1.6%; 95% CI: 1.0%-2.4%) actually focused on transfer and implementation. Of the 119 transfer studies, 37 (31.1%; 95% CI: 22.9-40.2%) evaluated the impact of a service or program, 28 (23.5%; 95% CI: 16.2%-32.2%) reported only process measures and 54 were descriptive. Of the 37 impact evaluation studies, 28 (75.7%; 95% CI: 58.8%-88.2%) appeared in peer reviewed journals but none included experimental designs. While services and programs are being transferred and implemented, few studies focus on the process by which this occurred or the effectiveness of the service or program in the new setting. Findings highlight a need for partnerships between

  10. How Giant Planets Shape the Characteristics of Terrestrial Planets

    Science.gov (United States)

    Barclay, Thomas; Quintana, Elisa V.

    2016-01-01

    The giant planets in the Solar System likely played a defining role in shaping the properties of the Earth and other terrestrial planets during their formation. Observations from the Kepler spacecraft indicate that terrestrial planets are highly abundant. However, there are hints that giant planets a few AU from their stars are not ubiquitous. It therefore seems reasonable to assume that many terrestrial planets lack a Jupiter-like companion. We use a recently developed, state-of-the-art N-body model that allows for collisional fragmentation to perform hundreds of numerical simulations of the final stages of terrestrial planet formation around a Sun-like star -- with and without giant outer planets. We quantify the effects that outer giant planet companions have on collisions and the planet accretion process. We focus on Earth-analogs that form in each system and explore how giant planets influence the relative frequency of giant impacts occurring at late times and the delivery of volitiles. This work has important implications for determining the frequency of habitable planets.

  11. Kepler constraints on planets near hot Jupiters

    Energy Technology Data Exchange (ETDEWEB)

    Steffen, Jason H.; /Fermilab; Ragozzine, Darin; /Harvard-Smithsonian Ctr. Astrophys.; Fabrycky, Daniel C.; /UC, Santa Cruz, Astron. Astrophys.; Carter, Joshua A.; /Harvard-Smithsonian Ctr. Astrophys.; Ford, Eric B.; /Florida U.; Holman, Matthew J.; /Harvard-Smithsonian Ctr. Astrophys.; Rowe, Jason F.; /NASA, Ames; Welsh, William F.; /San Diego State U., Astron. Dept.; Borucki, William J.; /NASA, Ames; Boss, Alan P.; /Carnegie Inst., Wash., D.C., DTM; Ciardi, David R.; /Caltech /Harvard-Smithsonian Ctr. Astrophys.

    2012-05-01

    We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 2:1 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly two-thirds to five times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history.

  12. Kepler constraints on planets near hot Jupiters

    CERN Document Server

    Steffen, Jason H; Fabrycky, Daniel C; Carter, Joshua A; Ford, Eric B; Holman, Matthew J; Rowe, Jason F; Welsh, William F; Borucki, William J; Boss, Alan P; Ciardi, David R; Quinn, Samuel N

    2012-01-01

    We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 days) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 2:1 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly 2/3 to 5 times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations or TTVs) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history.

  13. Kepler constraints on planets near hot Jupiters.

    Science.gov (United States)

    Steffen, Jason H; Ragozzine, Darin; Fabrycky, Daniel C; Carter, Joshua A; Ford, Eric B; Holman, Matthew J; Rowe, Jason F; Welsh, William F; Borucki, William J; Boss, Alan P; Ciardi, David R; Quinn, Samuel N

    2012-05-22

    We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 21 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly two-thirds to five times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history.

  14. Planet Hunters. V. A Confirmed Jupiter-size Planet in the Habitable Zone and 42 Planet Candidates from the Kepler Archive Data

    Science.gov (United States)

    Wang, Ji; Fischer, Debra A.; Barclay, Thomas; Boyajian, Tabetha S.; Crepp, Justin R.; Schwamb, Megan E.; Lintott, Chris; Jek, Kian J.; Smith, Arfon M.; Parrish, Michael; Schawinski, Kevin; Schmitt, Joseph R.; Giguere, Matthew J.; Brewer, John M.; Lynn, Stuart; Simpson, Robert; Hoekstra, Abe J.; Jacobs, Thomas Lee; LaCourse, Daryll; Schwengeler, Hans Martin; Chopin, Mike; Herszkowicz, Rafal

    2013-10-01

    We report the latest Planet Hunter results, including PH2 b, a Jupiter-size (R PL = 10.12 ± 0.56 R ⊕) planet orbiting in the habitable zone of a solar-type star. PH2 b was elevated from candidate status when a series of false-positive tests yielded a 99.9% confidence level that transit events detected around the star KIC 12735740 had a planetary origin. Planet Hunter volunteers have also discovered 42 new planet candidates in the Kepler public archive data, of which 33 have at least 3 transits recorded. Most of these transit candidates have orbital periods longer than 100 days and 20 are potentially located in the habitable zones of their host stars. Nine candidates were detected with only two transit events and the prospective periods are longer than 400 days. The photometric models suggest that these objects have radii that range between those of Neptune and Jupiter. These detections nearly double the number of gas-giant planet candidates orbiting at habitable-zone distances. We conducted spectroscopic observations for nine of the brighter targets to improve the stellar parameters and we obtained adaptive optics imaging for four of the stars to search for blended background or foreground stars that could confuse our photometric modeling. We present an iterative analysis method to derive the stellar and planet properties and uncertainties by combining the available spectroscopic parameters, stellar evolution models, and transiting light curve parameters, weighted by the measurement errors. Planet Hunters is a citizen science project that crowd sources the assessment of NASA Kepler light curves. The discovery of these 43 planet candidates demonstrates the success of citizen scientists at identifying planet candidates, even in longer period orbits with only two or three transit events. .

  15. PLANET HUNTERS. V. A CONFIRMED JUPITER-SIZE PLANET IN THE HABITABLE ZONE AND 42 PLANET CANDIDATES FROM THE KEPLER ARCHIVE DATA

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ji; Fischer, Debra A.; Boyajian, Tabetha S.; Schmitt, Joseph R.; Giguere, Matthew J.; Brewer, John M. [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Barclay, Thomas [NASA Ames Research Center, M/S 244-30, Moffett Field, CA 94035 (United States); Crepp, Justin R. [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Schwamb, Megan E. [Department of Physics, Yale University, P.O. Box 208121, New Haven, CT 06520 (United States); Lintott, Chris; Simpson, Robert [Oxford Astrophysics, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Jek, Kian J.; Hoekstra, Abe J.; Jacobs, Thomas Lee; LaCourse, Daryll; Schwengeler, Hans Martin; Smith, Arfon M.; Parrish, Michael; Lynn, Stuart [Adler Planetarium, 1300 South Lake Shore Drive, Chicago, IL 60605 (United States); Schawinski, Kevin, E-mail: ji.wang@yale.edu [Institute for Astronomy, Department of Physics, ETH Zurich, Wolfgang-Pauli-Strasse 16, CH-8093 Zurich (Switzerland); and others

    2013-10-10

    We report the latest Planet Hunter results, including PH2 b, a Jupiter-size (R{sub PL} = 10.12 ± 0.56 R{sub ⊕}) planet orbiting in the habitable zone of a solar-type star. PH2 b was elevated from candidate status when a series of false-positive tests yielded a 99.9% confidence level that transit events detected around the star KIC 12735740 had a planetary origin. Planet Hunter volunteers have also discovered 42 new planet candidates in the Kepler public archive data, of which 33 have at least 3 transits recorded. Most of these transit candidates have orbital periods longer than 100 days and 20 are potentially located in the habitable zones of their host stars. Nine candidates were detected with only two transit events and the prospective periods are longer than 400 days. The photometric models suggest that these objects have radii that range between those of Neptune and Jupiter. These detections nearly double the number of gas-giant planet candidates orbiting at habitable-zone distances. We conducted spectroscopic observations for nine of the brighter targets to improve the stellar parameters and we obtained adaptive optics imaging for four of the stars to search for blended background or foreground stars that could confuse our photometric modeling. We present an iterative analysis method to derive the stellar and planet properties and uncertainties by combining the available spectroscopic parameters, stellar evolution models, and transiting light curve parameters, weighted by the measurement errors. Planet Hunters is a citizen science project that crowd sources the assessment of NASA Kepler light curves. The discovery of these 43 planet candidates demonstrates the success of citizen scientists at identifying planet candidates, even in longer period orbits with only two or three transit events.

  16. Trojan twin planets

    Science.gov (United States)

    Dvorak, R.; Loibnegger, B.; Schwarz, R.

    2017-03-01

    The Trojan asteroids are moving in the vicinity of the stable Lagrange points L_4 and L_5 of the gas giants Jupiter, Uranus and Neptune. Their motion can be described and understood with the aid of the restricted three-body problem. As an extension of this problem we investigate how stable motion close to the Lagrange points of two massive bodies can exist. This configuration can be described as the Trojan Twin Problem when we regard the two additional bodies as having a mass significantly smaller than the the two primary bodies: a star in the center (m_1) and an additional Jupiter-like mass (m_2). Using this 4-body problem we have undertaken numerical investigations concerning possible stable "twin orbits". However, these two bodies (m_3 and m_4) in Trojan-like orbits may have quite different masses. We decided to choose 6 different scenaria for this problem: as primary body, m2, we have taken a Jupiter-like planet, a Saturn-like one, and a super-Earth with 10 Earthmasses (m_{Earth}) respectively. As quasi twin planets, we have used different mass ratios namely objects for m3 and m4 from 10m_{Earth} to Moon like ones. We found different stable configurations depending on the involved masses and the initial distances between the twins (always close to the Lagrange point). Although the formation of such a configuration seems to be not very probable we should not exclude that it exists regarding the huge number of planets even in our own galaxy. This model is of special interest when the most massive planet (m_2) is moving on an orbit in the habitable zone around a main sequence star. One can use our results of stable orbits of Trojan Twin Planets (or asteroids) for extrasolar systems having as second primary a Jupiter-like, a Saturn-like or a super-Earth like planet around a star similar to our Sun.

  17. Supporting Research and Technology Activities for a Microwave Observing Program to Search for Extraterrestrial Intelligence

    Science.gov (United States)

    Tarter, Jill; Backus, Peter

    1995-01-01

    Curriculum materials based on the search for extraterrestrial intelligence (SETI) were developed for grades 3 through 9 science classes. The project was supported in part by NASA. Six teacher's guides, plus ancillary visuals, addressing topics in astronomy, biology, chemistry, geosciences, and physics as well as mathematics, social sciences, and language arts, were designed by a team of teachers, scientists. curriculum developers, and artists. First drafts were piloted by 10 design team teachers; revised drafts were field tested by 109 teachers in 30 states. Extensive feedback from these teachers and their students and reviews by scientists were used to revise materials prior to submission to the publisher. The field test teachers overall ranking of all guides (data from individual lesson feedback forms) was 431 on a one low to five high scale; 85% found the content appropriate to course and grade level and 75% indicated they had no reservations about using the materials again or recommending them to colleagues. The ratio of liked to disliked student responses (from 1305 student letters) was 70:30. Most recommendations from the teachers, students, and science reviewers were incorporated in the final versions for the guides, published by Libraries Unlimited/Teacher Ideas Press, 1995.

  18. Planet Detection: The Kepler Mission

    Science.gov (United States)

    Jenkins, Jon M.; Smith, Jeffrey C.; Tenenbaum, Peter; Twicken, Joseph D.; Van Cleve, Jeffrey

    2012-03-01

    The search for exoplanets is one of the hottest topics in astronomy and astrophysics in the twenty-first century, capturing the public's attention as well as that of the astronomical community. This nascent field was conceived in 1989 with the discovery of a candidate planetary companion to HD114762 [35] and was born in 1995 with the discovery of the first extrasolar planet 51 Peg-b [37] orbiting a main sequence star. As of March, 2011, over 500 exoplanets have been discovered* and 106 are known to transit or cross their host star, as viewed from Earth. Of these transiting planets, 15 have been announced by the Kepler Mission, which was launched into an Earth-trailing, heliocentric orbit in March, 2009 [1,4,6,15,18,20,22,31,32,34,36,43]. In addition, over 1200 candidate transiting planets have already been detected by Kepler [5], and vigorous follow-up observations are being conducted to vet these candidates. As the false-positive rate for Kepler is expected to be quite low [39], Kepler has effectively tripled the number of known exoplanets. Moreover, Kepler will provide an unprecedented data set in terms of photometric precision, duration, contiguity, and number of stars. Kepler's primary science objective is to determine the frequency of Earth-size planets transiting their Sun-like host stars in the habitable zone, that range of orbital distances for which liquid water would pool on the surface of a terrestrial planet such as Earth, Mars, or Venus. This daunting task demands an instrument capable of measuring the light output from each of over 100,000 stars simultaneously with an unprecedented photometric precision of 20 parts per million (ppm) at 6.5-h intervals. The large number of stars is required because the probability of the geometrical alignment of planetary orbits that permit observation of transits is the ratio of the size of the star to the size of the planetary orbit. For Earth-like planets in 1-astronomical unit (AU) orbits† about sun-like stars

  19. Methane present in an extrasolar planet atmosphere

    CERN Document Server

    Swain, Mark R; Tinetti, Giovanna

    2008-01-01

    Molecules present in exoplanetary atmospheres are expected to strongly influence the atmospheric radiation balance, trace dynamical and chemical processes, and indicate the presence of disequilibrium effects. Since molecules have the potential to reveal the exoplanet atmospheric conditions and chemistry, searching for them is a high priority. The rotational-vibrational transition bands of water, carbon monoxide, and methane are anticipated to be the primary sources of non-continuum opacity in hot-Jovian planets. Since these bands overlap in wavelength, and the corresponding signatures from them are weak, decisive identification requires precision infrared spectroscopy. Here we report on a near-infrared transmission spectrum of the planet HD 189733b showing the presence of methane. Additionally, a resolved water-vapour band at 1.9 microns confirms the recent claim of water in this object. On thermochemical grounds, carbon-monoxide is expected to be abundant in the upper atmosphere of hot-Jovian exoplanets; thu...

  20. Searching for soft relativistic jets in core-collapse supernovae with the IceCube optical follow-up program

    Science.gov (United States)

    Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Allen, M. M.; Altmann, D.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Bay, R.; Bazo Alba, J. L.; Beattie, K.; Beatty, J. J.; Bechet, S.; Becker, J. K.; Becker, K.-H.; Benabderrahmane, M. L.; Benzvi, S.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D. Z.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D. J.; Bohm, C.; Bose, D.; Böser, S.; Botner, O.; Brown, A. M.; Buitink, S.; Caballero-Mora, K. S.; Carson, M.; Chirkin, D.; Christy, B.; Clevermann, F.; Cohen, S.; Colnard, C.; Cowen, D. F.; Cruz Silva, A. H.; D'Agostino, M. V.; Danninger, M.; Daughhetee, J.; Davis, J. C.; de Clercq, C.; Degner, T.; Demirörs, L.; Descamps, F.; Desiati, P.; de Vries-Uiterweerd, G.; Deyoung, T.; Díaz-Vélez, J. C.; Dierckxsens, M.; Dreyer, J.; Dumm, J. P.; Dunkman, M.; Eisch, J.; Ellsworth, R. W.; Engdegård, O.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Fedynitch, A.; Feintzeig, J.; Feusels, T.; Filimonov, K.; Finley, C.; Fischer-Wasels, T.; Fox, B. D.; Franckowiak, A.; Franke, R.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Gladstone, L.; Glüsenkamp, T.; Goldschmidt, A.; Goodman, J. A.; Góra, D.; Grant, D.; Griesel, T.; Groß, A.; Grullon, S.; Gurtner, M.; Ha, C.; Haj Ismail, A.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Heinen, D.; Helbing, K.; Hellauer, R.; Herquet, P.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Hoffmann, B.; Homeier, A.; Hoshina, K.; Huelsnitz, W.; Hülß, J.-P.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Ishihara, A.; Jacobi, E.; Jacobsen, J.; Japaridze, G. S.; Johansson, H.; Kampert, K.-H.; Kappes, A.; Karg, T.; Karle, A.; Kenny, P.; Kiryluk, J.; Kislat, F.; Klein, S. R.; Köhne, J.-H.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Kopper, S.; Koskinen, D. J.; Kowalski, M.; Kowarik, T.; Krasberg, M.; Kroll, G.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Laihem, K.; Landsman, H.; Larson, M. J.; Lauer, R.; Lünemann, J.; Madsen, J.; Marotta, A.; Maruyama, R.; Mase, K.; Matis, H. S.; Meagher, K.; Merck, M.; Mészáros, P.; Meures, T.; Miarecki, S.; Middell, E.; Milke, N.; Miller, J.; Montaruli, T.; Morse, R.; Movit, S. M.; Nahnhauer, R.; Nam, J. W.; Naumann, U.; Nygren, D. R.; Odrowski, S.; Olivas, A.; Olivo, M.; O'Murchadha, A.; Panknin, S.; Paul, L.; Pérez de Los Heros, C.; Petrovic, J.; Piegsa, A.; Pieloth, D.; Porrata, R.; Posselt, J.; Price, P. B.; Przybylski, G. T.; Rawlins, K.; Redl, P.; Resconi, E.; Rhode, W.; Ribordy, M.; Richman, M.; Rodrigues, J. P.; Rothmaier, F.; Rott, C.; Ruhe, T.; Rutledge, D.; Ruzybayev, B.; Ryckbosch, D.; Sander, H.-G.; Santander, M.; Sarkar, S.; Schatto, K.; Schmidt, T.; Schönwald, A.; Schukraft, A.; Schultes, A.; Schulz, O.; Schunck, M.; Seckel, D.; Semburg, B.; Seo, S. H.; Sestayo, Y.; Seunarine, S.; Silvestri, A.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stezelberger, T.; Stokstad, R. G.; Stössl, A.; Strahler, E. A.; Ström, R.; Stüer, M.; Sullivan, G. W.; Swillens, Q.; Taavola, H.; Taboada, I.; Tamburro, A.; Ter-Antonyan, S.; Tilav, S.; Toale, P. A.; Toscano, S.; Tosi, D.; van Eijndhoven, N.; Vandenbroucke, J.; van Overloop, A.; van Santen, J.; Vehring, M.; Voge, M.; Walck, C.; Waldenmaier, T.; Wallraff, M.; Walter, M.; Weaver, Ch.; Wendt, C.; Westerhoff, S.; Whitehorn, N.; Wiebe, K.; Wiebusch, C. H.; Williams, D. R.; Wischnewski, R.; Wissing, H.; Wolf, M.; Wood, T. R.; Woschnagg, K.; Xu, C.; Xu, D. L.; Xu, X. W.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Zarzhitsky, P.; Zoll, M.; IceCube Collaboration; Akerlof, C. W.; Pandey, S. B.; Yuan, F.; Zheng, W.; ROTSE Collaboration

    2012-03-01

    Context. Transient neutrino sources such as gamma-ray bursts (GRBs) and supernovae (SNe) are hypothesized to emit bursts of high-energy neutrinos on a time-scale of ≲100 s. While GRB neutrinos would be produced in high relativistic jets, core-collapse SNe might host soft-relativistic jets, which become stalled in the outer layers of the progenitor star leading to an efficient production of high-energy neutrinos. Aims: To increase the sensitivity to these neutrinos and identify their sources, a low-threshold optical follow-up program for neutrino multiplets detected with the IceCube observatory has been implemented. Methods: If a neutrino multiplet, i.e. two or more neutrinos from the same direction within 100 s, is found by IceCube a trigger is sent to the Robotic Optical Transient Search Experiment, ROTSE. The 4 ROTSE telescopes immediately start an observation program of the corresponding region of the sky in order to detect an optical counterpart to the neutrino events. Results: No statistically significant excess in the rate of neutrino multiplets has been observed and furthermore no coincidence with an optical counterpart was found. Conclusions: The search allows, for the first time, to set stringent limits on current models predicting a high-energy neutrino flux from soft relativistic hadronic jets in core-collapse SNe. We conclude that a sub-population of SNe with typical Lorentz boost factor and jet energy of 10 and 3 × 1051 erg, respectively, does not exceed 4.2% at 90% confidence.

  1. Global stratigraphy. [of planet Mars

    Science.gov (United States)

    Tanaka, Kenneth L.; Scott, David H.; Greeley, Ronald

    1992-01-01

    Attention is given to recent major advances in the definition and documentation of Martian stratigraphy and geology. Mariner 9 provided the images for the first global geologic mapping program, resulting in the recognition of the major geologic processes that have operated on the planet, and in the definition of the three major chronostratigraphic divisions: the Noachian, Hesperian, and Amazonian Systems. Viking Orbiter images permitted the recognition of additional geologic units and the formal naming of many formations. Epochs are assigned absolute ages based on the densities of superposed craters and crater-flux models. Recommendations are made with regard to future areas of study, namely, crustal stratigraphy and structure, the highland-lowland boundary, the Tharsis Rise, Valles Marineris, channels and valley networks, and possible Martian oceans, lakes, and ponds.

  2. Tc trends and terrestrial planet formation: The case of Zeta Reticuli

    OpenAIRE

    Adibekyan Vardan; Elisa Delgado-Mena; Pedro Figueira; Sergio Sousa; Nuno Santos; Joao Faria; Jonay González Hernández; Garik Israelian; Gohar Harutyunyan; Lucia Suárez-Andrés; Arthur Hakobyan

    2016-01-01

    During the last decade astronomers have been trying to search for chemical signatures of terrestrial planet formation in the atmospheres of the hosting stars. Several studies suggested that the chemical abundance trend with the condensation temperature, Tc, is a signature of rocky planet formation.  In particular, it was suggested that the Sun shows 'peculiar' chemical abundances due to the presence of the terrestrial planets in our solar-system. However, the rocky material accretion or the t...

  3. Planning and management of water resource programs. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    The bibliography contains citations concerning planning and management of water resource programs and projects at the local, regional, state, and national levels. The studies of water quality, drinking water, industrial water, and irrigation are presented. Topics include groundwater and surface water management, flood control, waste water treatment, hydroelectric power generation, sanitation and toxic hazards, models and risk assessment, and remote sensing technology. Worldwide water management is covered.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  4. Pluto and other dwarf planets

    CERN Document Server

    Saxena, Shalini

    2017-01-01

    The reclassification of Pluto in 2006 not only decreased the number of planets in our solar system by one but also introduced the new category of dwarf planet. Readers will come to understand what separates a dwarf planet from a planet-or for that matter from any of the other bodies found within the solar system. They'll learn about Pluto itself, as well as its fellow dwarf planets, Ceres, Makemake, Haumea, and Eris. Full of recent information, this title is sure to inspire an interest in space science among young readers.

  5. M stars as targets for terrestrial exoplanet searches and biosignature detection.

    Science.gov (United States)

    Scalo, John; Kaltenegger, Lisa; Segura, Antígona; Segura, Ant Gona; Fridlund, Malcolm; Ribas, Ignasi; Kulikov, Yu N; Grenfell, John L; Rauer, Heike; Odert, Petra; Leitzinger, Martin; Selsis, F; Khodachenko, Maxim L; Eiroa, Carlos; Kasting, Jim; Lammer, Helmut

    2007-02-01

    intense and frequent stellar flares and sporadic energetic particle events, and impact erosion, both enhanced, the former dramatically, for M star HZ semimajor axes. Loss of atmosphere by interactions with energetic particles is likely unless the planetary magnetic moment is sufficiently large. For the smallest stellar masses a period of high planetary surface temperature, while the parent star approaches the main sequence, must be endured. The formation and retention of a thick atmosphere and a strong magnetic field as buffers for a sufficiently massive planet emerge as prerequisites for an M star planet to enter a long period of stability with its habitability intact. However, the star will then be subjected to short-term fluctuations with consequences including frequent unpredictable variation in atmospheric chemistry and surficial radiation field. After a review of evidence concerning disks and planets associated with M stars, we evaluate M stars as targets for future HZ planet search programs. Strong advantages of M stars for most approaches to HZ detection are offset by their faintness, leading to severe constraints due to accessible sample size, stellar crowding (transits), or angular size of the HZ (direct imaging). Gravitational lensing is unlikely to detect HZ M star planets because the HZ size decreases with mass faster than the Einstein ring size to which the method is sensitive. M star Earth-twin planets are predicted to exhibit surprisingly strong bands of nitrous oxide, methyl chloride, and methane, and work on signatures for other climate categories is summarized. The rest of the paper is devoted to an examination of evidence and implications of the unusual radiation and particle environments for atmospheric chemistry and surface radiation doses, and is summarized in the Synopsis. We conclude that attempts at remote sensing of biosignatures and nonbiological markers from M star planets are important, not as tests of any quantitative theories or rational

  6. Mars - an escaping planet?

    CERN Document Server

    Dvorak, R

    2005-01-01

    The chaotic behaviour of the motion of the planets in our Solar System is well established. Numerical experiments with a modified Solar System consisting of a more massive Earth have shown, that for special values of an enlargement factor K around 5 the dynamical state of a truncated planetary system (excluding Mercury and the outer planets Uranus and Neptune) is highly chaotic. On the contrary for values of the mass of the Earth up to the mass of Saturn no irregular dynamical behaviour was observed. We extended our investigations to the complete planetary system and showed, that this chaotic window found before still exists. Tests in different 'Solar Systems' showed that only including Jupiter and Saturn with their actual masses together with a 'massive' Earth (between 4 and 6 times more massive) destabilize the orbit of Mars so that even escapes from the system are possible.

  7. Astrometric Detection of Earthlike Planets

    CERN Document Server

    Shao, Michael; Catanzarite, Joseph H; Edberg, Stephen J; Leger, Alain; Malbet, Fabien; Queloz, Didier; Muterspaugh, Matthew W; Beichman, Charles; Fischer, Debra A; Ford, Eric; Olling, Robert; Kulkarni, Shrinivas; Unwin, Stephen C; Traub, Wesley

    2009-01-01

    Astrometry can detect rocky planets in a broad range of masses and orbital distances and measure their masses and three-dimensional orbital parameters, including eccentricity and inclination, to provide the properties of terrestrial planets. The masses of both the new planets and the known gas giants can be measured unambiguously, allowing a direct calculation of the gravitational interactions, both past and future. Such dynamical interactions inform theories of the formation and evolution of planetary systems, including Earth-like planets. Astrometry is the only technique technologically ready to detect planets of Earth mass in the habitable zone (HZ) around solar-type stars within 20 pc. These Earth analogs are close enough for follow-up observations to characterize the planets by infrared imaging and spectroscopy with planned future missions such as the James Webb Space Telescope (JWST) and the Terrestrial Planet Finder/Darwin. Employing a demonstrated astrometric precision of 1 microarcsecond and a noise ...

  8. Observed properties of extrasolar planets.

    Science.gov (United States)

    Howard, Andrew W

    2013-05-03

    Observational surveys for extrasolar planets probe the diverse outcomes of planet formation and evolution. These surveys measure the frequency of planets with different masses, sizes, orbital characteristics, and host star properties. Small planets between the sizes of Earth and Neptune substantially outnumber Jupiter-sized planets. The survey measurements support the core accretion model, in which planets form by the accumulation of solids and then gas in protoplanetary disks. The diversity of exoplanetary characteristics demonstrates that most of the gross features of the solar system are one outcome in a continuum of possibilities. The most common class of planetary system detectable today consists of one or more planets approximately one to three times Earth's size orbiting within a fraction of the Earth-Sun distance.

  9. Extrasolar planet detection

    Science.gov (United States)

    Korechoff, R. P.; Diner, D. J.; Tubbs, E. F.; Gaiser, S. L.

    1994-01-01

    This paper discusses the concept of extrasolar planet detection using a large-aperture infared imaging telescope. Coronagraphic stellar apodization techniques are less efficient at infrared wavelengths compared to the visible, as a result of practical limitations on aperture dimensions, thus necessitating additional starlight suppression to make planet detection feasible in this spectral domain. We have been investigating the use of rotational shearing interferometry to provide up to three orders of magnitude of starlight suppression over broad spectral bandwidths. We present a theoretical analysis of the system performance requirements needed to make this a viable instrument for planet detection, including specifications on the interferometer design and telescope aperture characteristics. The concept of using rotational shearing interferometry as a wavefront error detector, thus providing a signal that can be used to adaptively correct the wavefront, will be discussed. We also present the status of laboratory studies of on-axis source suppression using a recently constructed rotational shearing interferometer that currently operates in the visible.

  10. Planets and Dark Energy

    CERN Document Server

    Gibson, Carl H

    2008-01-01

    Self gravitational fluid mechanical methods termed hydro-gravitational-dynamics (HGD) predict plasma fragmentation 0.03 Myr after the turbulent big bang to form protosuperclustervoids, turbulent protosuperclusters, and protogalaxies at the 0.3 Myr transition from plasma to gas. Linear protogalaxyclusters fragment at 0.003 Mpc viscous-inertial scales along turbulent vortex lines or in spirals, as observed. The plasma protogalaxies fragment on transition into white-hot planet-mass gas clouds (PFPs) in million-solar-mass clumps (PGCs) that become globular-star-clusters (GCs) from tidal forces or dark matter (PGCs) by freezing and diffusion into 0.3 Mpc halos with 97% of the galaxy mass. The weakly collisional non-baryonic dark matter diffuses to > Mpc scales and fragments to form galaxy cluster halos. Stars and larger planets form by binary mergers of the trillion PFPs per PGC, mostly on 0.03 Mpc galaxy accretion disks. Stars deaths depend on rates of planet accretion and internal star mixing. Moderate accretion...

  11. Planet Formation with Migration

    CERN Document Server

    Chambers, J E

    2006-01-01

    In the core-accretion model, gas-giant planets form solid cores which then accrete gaseous envelopes. Tidal interactions with disk gas cause a core to undergo inward type-I migration in 10^4 to 10^5 years. Cores must form faster than this to survive. Giant planets clear a gap in the disk and undergo inward type-II migration in <10^6 years if observed disk accretion rates apply to the disk as a whole. Type-II migration times exceed typical disk lifetimes if viscous accretion occurs mainly in the surface layers of disks. Low turbulent viscosities near the midplane may allow planetesimals to form by coagulation of dust grains. The radius r of such planetesimals is unknown. If r<0.5 km, the core formation time is shorter than the type-I migration timescale and cores will survive. Migration is substantial in most cases, leading to a wide range of planetary orbits, consistent with the observed variety of extrasolar systems. When r is of order 100m and midplane alpha is of order 3 times 10^-5, giant planets si...

  12. Microlensing Discovery of an Earth-Mass Planet

    Science.gov (United States)

    Kohler, Susanna

    2017-04-01

    What do we know about planet formation around stars that are so light that they cant fuse hydrogen in their cores? The new discovery of an Earth-mass planet orbiting what is likely a brown dwarf may help us better understand this process.Planets Around Brown Dwarfs?Comparison of the sizes of the Sun, a low-mass star, a brown dwarf, Jupiter, and Earth. [NASA/JPL-Caltech/UCB]Planets are thought to form from the material inprotoplanetary disks around their stellar hosts. But the lowest-mass end of the stellar spectrum brown dwarfs, substellar objects so light that they straddle the boundary between planet and star will have correspondingly light disks. Do brown dwarfs disks typically have enough mass to form Earth-mass planets?To answer this question, scientists have searched for planets around brown dwarfs with marginal success. Thus far, only four such planets have been found and these systems may not be typical, since they were discovered via direct imaging. To build a more representative sample, wed like to discover exoplanets around brown dwarfs via a method that doesnt rely on imaging the faint light of the system.A diagram of how planets are detected via gravitational microlensing. The detectable planet is in orbit around the foreground lens star. [NASA]Lensed Light as a GiveawayConveniently, such a method exists and its recently been used to make a major discovery! The planet OGLE-2016-BLG-1195Lb was detected as a result of a gravitational microlensing event that was observed both from the ground and from space.The discovery of a planet via microlensing occurs when the light of a distant source star is magnified by a passing foreground star hosting a planet. The light curve of the source shows a distinctive magnification signature as a result of the gravitational lensing from the foreground star, and the gravitational field of the lensing stars planet can add its own detectable blip to the curve.OGLE-2016-BLG-1195LbThe magnification curve of OGLE-2016-BLG-1195

  13. Speckle Imaging of Kepler Exo-planet Transit Candidate Stars

    Science.gov (United States)

    Howell, Steve B.; Horch, Elliott; Sherry, William

    2009-08-01

    The NASA Kepler mission was successfully launched on 6 March 2009 and will begin science operations near 1 May. At the present time, commissioning tests are being performed and all spacecraft and science instruments are nominal. Kepler's main science focus is to discover Earth-like exo-planets via photometric transit detection. ``Hot Jupiters" will be found by the hundreds (using current ground-based statistics) but Earth-sized planets (up to 2.5 Earth radii) will be more difficult, yet are the holy grail of the mission. To take the list of candidate transiting planets found by Kepler and move them to probable or certain exo-planet detections, a decision tree of false positive elimination will occur. While earth-sized exo-planets can not currently be confirmed from the ground, many of the false positive eliminations steps can be performed. This proposal aims to obtain high resolution speckle imaging to 1) finish the characterization of ~500 comparison sample stars in the Kepler field of view prior to any transit information as a sample to place planet host stars in context with and to 2) observe Kepler exo-planet transit candidates in order to eliminate the largest false positive contributor in any transit search - background eclipsing binary stars or faint companion stars.

  14. Giant Planet Occurrence in the Stellar Mass-Metallicity Plane

    CERN Document Server

    Johnson, John Asher; Howard, Andrew W; Crepp, Justin R

    2010-01-01

    Correlations between stellar properties and the occurrence rate of exoplanets can be used to inform the target selection of future planet search efforts and provide valuable clues about the planet formation process. We analyze a sample of 1194 stars drawn from the California Planet Survey targets to determine the empirical functional form describing the likelihood of a star harboring a giant planet as a function of its mass and metallicity. Our stellar sample ranges from M dwarfs with masses as low as 0.2 Msun to intermediate-mass subgiants with masses as high as 1.9 Msun. In agreement with previous studies, our sample exhibits a planet-metallicity correlation at all stellar masses; the fraction of stars that harbor giant planets scales as f \\propto 10^{1.2 [Fe/H]}. We can rule out a flat metallicity relationship among our evolved stars (at 98% confidence), which argues that the high metallicities of stars with planets is not likely due to convective envelope ``pollution.'' Our data also rule out a constant p...

  15. Volatiles and refratories in solar analogs: no terrestial planet connection

    CERN Document Server

    Hernandez, J I Gonzalez; Santos, N C; Sousa, S; Delgado-Mena, E; Neves, V; Udry, S

    2010-01-01

    We have analysed very high-quality HARPS and UVES spectra of 95 solar analogs, 24 hosting planets and 71 without detected planets, to search for any possible signature of terrestial planets in the chemical abundances of volatile and refractory elements with respect to the solar abundances. We demonstrate that stars with and without planets in this sample show similar mean abundance ratios, in particular, a sub-sample of 14 planet-host and 14 "single" solar analogs in the metallicity range 0.14<[Fe/H]<0.36. In addition, two of the planetary systems in this sub-sample, containing each of them a super-Earth-like planet with masses in the range ~ 7-11 Earth masses, have different volatile-to-refratory abundance ratios to what would be expected from the presence of a terrestial planets. Finally, we check that after removing the Galactic chemical evolution effects any possible difference in mean abundances, with respect to solar values, of refratory and volatile elements practically dissappears.

  16. Climate Stability of Habitable Earth-like Planets

    CERN Document Server

    Menou, Kristen

    2014-01-01

    The carbon-silicate cycle regulates the atmospheric $CO_2$ content of terrestrial planets on geological timescales through a balance between the rates of $CO_2$ volcanic outgassing and planetary intake from rock weathering. It is thought to act as an efficient climatic thermostat on Earth and, by extension, on other habitable planets. If, however, the weathering rate increases with the atmospheric $CO_2$ content, as expected on planets lacking land vascular plants, the carbon-silicate cycle feedback can become severely limited. Here we show that Earth-like planets receiving less sunlight than current Earth may no longer possess a stable warm climate but instead repeatedly cycle between unstable glaciated and deglaciated climatic states. This has implications for the search for life on exoplanets in the habitable zone of nearby stars.

  17. Climate stability of habitable Earth-like planets

    Science.gov (United States)

    Menou, Kristen

    2015-11-01

    The carbon-silicate cycle regulates the atmospheric CO2 content of terrestrial planets on geological timescales through a balance between the rates of CO2 volcanic outgassing and planetary intake from rock weathering. It is thought to act as an efficient climatic thermostat on Earth and, by extension, on other habitable planets. If, however, the weathering rate increases with the atmospheric CO2 content, as expected on planets lacking land vascular plants, the carbon-silicate cycle feedback can become severely limited. Here we show that Earth-like planets receiving less sunlight than current Earth may no longer possess a stable warm climate but instead repeatedly cycle between unstable glaciated and deglaciated climatic states. This has implications for the search for life on exoplanets in the habitable zone of nearby stars.

  18. Influence of Stellar Multiplicity On Planet Formation. II. Planets Are Less Common in Multiple-Star Systems with Separations Smaller than 1500 AU

    CERN Document Server

    Wang, Ji; Xie, Ji-Wei; Ciardi, David R

    2014-01-01

    Almost half of the stellar systems in the solar neighborhood are made up of multiple stars. In multiple-star systems, planet formation is under the dynamical influence of stellar companions, and the planet occurrence rate is expected to be different from that for single stars. There have been numerous studies on the planet occurrence rate of single star systems. However, to fully understand planet formation, the planet occurrence rate in multiple-star systems needs to be addressed. In this work, we {{infer}} the planet occurrence rate in multiple-star systems by measuring the stellar multiplicity rate for planet host stars. For a sub-sample of 56 $Kepler$ planet host stars, we use adaptive optics (AO) imaging and the radial velocity (RV) technique to search for stellar companions. The combination of these two techniques results in high search completeness for stellar companions. We detect 59 visual stellar companions to 25 planet host stars with AO data. {{Three stellar companions are within 2$^{\\prime\\prime}...

  19. Strategies for the search of life in the universe

    OpenAIRE

    Schneider, Jean

    1996-01-01

    The discovery of an increasing number of Jupiter-like planets in orbit around other stars (or extra-solar planets) is a promising first step toward the search for Life in the Universe. We review all aspects of the question: - definition of Life - definition and characterization of the `habitable zone' around a star - overview of detection methods of planets, with special attention to habitable planets - present fingings - future projects.

  20. Final Report---Next-Generation Solvers for Mixed-Integer Nonlinear Programs: Structure, Search, and Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Linderoth, Jeff T. [University of Wisconsin-Madison; Luedtke, James R. [University of Wisconsin-Madison

    2013-05-30

    The mathematical modeling of systems often requires the use of both nonlinear and discrete components. Problems involving both discrete and nonlinear components are known as mixed-integer nonlinear programs (MINLPs) and are among the most challenging computational optimization problems. This research project added to the understanding of this area by making a number of fundamental advances. First, the work demonstrated many novel, strong, tractable relaxations designed to deal with non-convexities arising in mathematical formulation. Second, the research implemented the ideas in software that is available to the public. Finally, the work demonstrated the importance of these ideas on practical applications and disseminated the work through scholarly journals, survey publications, and conference presentations.

  1. Our changing planet: The FY 1993 US global change research program. A supplement to the US President's fiscal year 1993 budget

    Science.gov (United States)

    1992-01-01

    An improved predictive understanding of the integrated Earth system, including human interactions, will provide direct benefits by anticipating and planning for possible impacts on commerce, agriculture, energy, resource utilization, human safety, and environmental quality. The central goal of the U.S. Global Change Research Program (USGCRP) is to help establish the scientific understanding and the basis for national and international policymaking related to natural and human-induced changes in the global Earth system. This will be accomplished through: (1) establishing an integrated, comprehensive, long-term program of documenting the Earth system on a global scale; (2) conducting a program of focused studies to improve our understanding of the physical, geological, chemical, biological, and social processes that influence the Earth system processes; and (3) developing integrated conceptual and predictive Earth system models.

  2. Search for Lambda+(c) ---> p K+ pi- and D+(s) ---> K+ K+ pi- using genetic programming event selection

    Energy Technology Data Exchange (ETDEWEB)

    Link, J.M.; Yager, P.M.; Anjos, J.C.; Bediaga, I.; Castromonte, C.; Machado, A.A.; Magnin, J.; Massafferri, A.; de Miranda, J.M.; Pepe, I.M.; Polycarpo, E.; dos Reis,; Carrillo, S.; Casimiro, E.; Cuautle, E.; Sanchez-Hernandez, A.; Uribe, C.; Vazquez, F.; Agostino, L.; Cinquini, L.; Cumalat, J.P.; /Wisconsin U., Madison

    2005-07-01

    The authors apply a genetic programming technique to search for the doubly Cabibbo suppressed decays {Lambda}{sub c}{sup +} {yields} pK{sup +} {pi}{sup -} and D{sub s}{sup +} {yields} K{sup +}K{sup +}{pi}{sup -}. They normalize these decays to their Cabibbo favored partners and find BR({Lambda}{sub c}{sup +} {yields} pK{sup +}{pi}{sup -})/BR({Lambda}{sub c}{sup +} {yields} pK{sup -}{pi}{sup +}) = (0.05 {+-} 0.26 {+-} 0.02)% and BR(D{sub s}{sup +} {yields} K{sup +}K{sup +}{pi}{sup -})/BR(D{sub s}{sup +} {yields} K{sup -}K{sup +}{pi}{sup +}) = (0.52 {+-} 0.17 {+-} 0.11)% where the first errors are statistical and the second are systematic. Expressed as 90% confidence levels (CL), they find < 0.46% and < 0.78% respectively. This is the first successful use of genetic programming in a high energy physics data analysis.

  3. Searching for soft relativistic jets in Core-collapse Supernovae with the IceCube Optical Follow-up Program

    CERN Document Server

    Abbasi, R; Abu-Zayyad, T; Ackermann, M; Adams, J; Aguilar, J A; Ahlers, M; Allen, M M; Altmann, D; Andeen, K; Auffenberg, J; Bai, X; Baker, M; Barwick, S W; Bay, R; Alba, J L Bazo; Beattie, K; Beatty, J J; Bechet, S; Becker, J K; Becker, K -H; Benabderrahmane, M L; BenZvi, S; Berdermann, J; Berghaus, P; Berley, D; Bernardini, E; Bertrand, D; Besson, D Z; Bindig, D; Bissok, M; Blaufuss, E; Blumenthal, J; Boersma, D J; Bohm, C; Bose, D; Böser, S; Botner, O; Brown, A M; Buitink, S; Caballero-Mora, K S; Carson, M; Chirkin, D; Christy, B; Clevermann, F; Cohen, S; Colnard, C; Cowen, D F; Silva, A H Cruz; D'Agostino, M V; Danninger, M; Daughhetee, J; Davis, J C; De Clercq, C; Degner, T; Demirörs, L; Descamps, F; Desiati, P; de Vries-Uiterweerd, G; DeYoung, T; Díaz-Vélez, J C; Dierckxsens, M; Dreyer, J; Dumm, J P; Dunkman, M; Eisch, J; Ellsworth, R W; Engdegård, O; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Fedynitch, A; Feintzeig, J; Feusels, T; Filimonov, K; Finley, C; Fischer-Wasels, T; Fox, B D; Franckowiak, A; Franke, R; Gaisser, T K; Gallagher, J; Gerhardt, L; Gladstone, L; Glüsenkamp, T; Goldschmidt, A; Goodman, J A; Góra, D; Grant, D; Griesel, T; Groß, A; Grullon, S; Gurtner, M; Ha, C; Ismail, A Haj; Hallgren, A; Halzen, F; Han, K; Hanson, K; Heinen, D; Helbing, K; Hellauer, R; Herquet, P; Hickford, S; Hill, G C; Hoffman, K D; Hoffmann, B; Homeier, A; Hoshina, K; Huelsnitz, W; Hülß, J -P; Hulth, P O; Hultqvist, K; Hussain, S; Ishihara, A; Jacobi, E; Jacobsen, J; Japaridze, G S; Johansson, H; Kampert, K -H; Kappes, A; Karg, T; Karle, A; Kenny, P; Kiryluk, J; Kislat, F; Klein, S R; Köhne, J -H; Kohnen, G; Kolanoski, H; Köpke, L; Kopper, S; Koskinen, D J; Kowalski, M; Kowarik, T; Krasberg, M; Kroll, G; Kurahashi, N; Kuwabara, T; Labare, M; Laihem, K; Landsman, H; Larson, M J; Lauer, R; Lünemann, J; Madsen, J; Marotta, A; Maruyama, R; Mase, K; Matis, H S; Meagher, K; Merck, M; Mészáros, P; Meures, T; Miarecki, S; Middell, E; Milke, N; Miller, J; Montaruli, T; Morse, R; Movit, S M; Nahnhauer, R; Nam, J W; Naumann, U; Nygren, D R; Odrowski, S; Olivas, A; Olivo, M; O'Murchadha, A; Panknin, S; Paul, L; Heros, C Pérez de los; Petrovic, J; Piegsa, A; Pieloth, D; Porrata, R; Posselt, J; Price, P B; Przybylski, G T; Rawlins, K; Redl, P; Resconi, E; Rhode, W; Ribordy, M; Richman, M; Rodrigues, J P; Rothmaier, F; Rott, C; Ruhe, T; Rutledge, D; Ruzybayev, B; Ryckbosch, D; Sander, H -G; Santander, M; Sarkar, S; Schatto, K; Schmidt, T; Schönwald, A; Schukraft, A; Schultes, A; Schulz, O; Schunck, M; Seckel, D; Semburg, B; Seo, S H; Sestayo, Y; Seunarine, S; Silvestri, A; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stezelberger, T; Stokstad, R G; Stössl, A; Strahler, E A; Ström, R; Stüer, M; Sullivan, G W; Swillens, Q; Taavola, H; Taboada, I; Tamburro, A; Ter-Antonyan, S; Tilav, S; Toale, P A; Toscano, S; Tosi, D; van Eijndhoven, N; Vandenbroucke, J; Van Overloop, A; van Santen, J; Vehring, M; Voge, M; Walck, C; Waldenmaier, T; Wallraff, M; Walter, M; Weaver, Ch; Wendt, C; Westerhoff, S; Whitehorn, N; Wiebe, K; Wiebusch, C H; Williams, D R; Wischnewski, R; Wissing, H; Wolf, M; Wood, T R; Woschnagg, K; Xu, C; Xu, D L; Xu, X W; Yanez, J P; Yodh, G; Yoshida, S; Zarzhitsky, P; Akerlof, C W; Pandey, S B; Yuan, F; Zheng, W

    2011-01-01

    Context. Transient neutrino sources such as Gamma-Ray Bursts (GRBs) and Supernovae (SNe) are hypothesized to emit bursts of high-energy neutrinos on a time-scale of \\lesssim 100 s. While GRB neutrinos would be produced in high relativistic jets, core-collapse SNe might host soft-relativistic jets, which become stalled in the outer layers of the progenitor star leading to an efficient production of high-energy neutrinos. Aims. To increase the sensitivity to these neutrinos and identify their sources, a low-threshold optical follow-up program for neutrino multiplets detected with the IceCube observatory has been implemented. Methods. If a neutrino multiplet, i.e. two or more neutrinos from the same direction within 100 s, is found by IceCube a trigger is sent to the Robotic Optical Transient Search Experiment, ROTSE. The 4 ROTSE telescopes immediately start an observation program of the corresponding region of the sky in order to detect an optical counterpart to the neutrino events. Results. No statistically si...

  4. In Search of Exomoons

    CERN Document Server

    Kipping, David M

    2014-01-01

    Two decades ago, astronomers began detecting planets orbiting stars other than our Sun, so-called exoplanets. Since that time, the rate of detections and the sensitivity to ever-smaller planets has improved dramatically with several Earth-sized planets now known. As our sensitivity dives into the terrestrial regime, increasingly the community has wondered if the moons of exoplanets may also be detectable, so-called "exomoons". Their detection represents an outstanding challenge in modern astronomy and would provide deep insights into the uniqueness of our Solar System and perhaps even expand the definition of habitability. Here, I will briefly review theoretical studies exploring the formation and evolution of exomoons, which serve to guide observational searches and provide testable hypotheses. Next, I will outline the different methods which have been proposed to accomplish this challenging feat and their respective merits. Finally, initial results from observational efforts will be summarized with a view t...

  5. Simulations for terrestrial planets formation

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper,the formation of terrestrial planets in the late stage of planetary formation is investigated using the two-planet model.At that time,the protostar formed for about 3 Ma and the gas disk dissipated.In the model,the perturbations from Jupiter and Saturn are considered.Variations of the mass of outer planet,and the initial eccentricities and inclinations of embryos and planetesimals are also considered.Our results show that,terrestrial planets are formed in 50 Ma,and the accretion rate is about 60%-80%.In each simulation,3-4 terrestrial planets are formed inside"Jupiter"with masses of 0.15 -3.6M⊕.In the 0.5-4 AU,when the eccentricities of planetesimals are excited,planetesimals are able to accrete material from wide radial direction.The plenty of water material of the terrestrial planet in the Habitable Zone may be transferred from the farther places by this mechanism.Accretion could also happen a few times between two major planets only if the outer planet has a moderate mass and the small terrestrial planet could survive at some resonances over time scale of 10 8 a.In one of our simulations,commensurability of the orbital periods of planets is very common.Moreover,a librating-circulating 3:2 configuration of mean motion resonance is found.

  6. Simulations for terrestrial planets formation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Niu; JI JiangHui

    2009-01-01

    In this paper, the formation of terrestrial planets in the late stage of planetary formation is Investigated using the two-planet model. At that time, the protostar formed for about 3 Ma and the gas disk dissipated. In the model, the perturbations from Jupiter and Saturn are considered. Variations of the mass of outer planet, and the initial eccentricities and inclinations of embryos and planetesimals are also considered. Our results show that, terrestrial planets are formed in 50 Ma, and the accretion rate is about 60%-80%. In each simulation, 3-4 terrestrial planets are formed inside "Jupiter" with masses of 0.15-3.6 M(⊙). In the 0.5-4 AU, when the eccentricities of planetesimals are excited, planetesimals are able to accrete material from wide radial direction. The plenty of water material of the terrestrial planet in the Habitable Zone may be transferred from the farther places by this mechanism. Accretion could also happen a few times between two major planets only if the outer planet has a moderate mass and the small terrestrial planet could survive at some resonances over time scale of 108a. In one of our simulations, commensurability of the orbital periods of planets is very common. Moreover, a librating-circulating 3:2 configuration of mean motion resonance is found.

  7. Taxonomy of the extrasolar planet.

    Science.gov (United States)

    Plávalová, Eva

    2012-04-01

    When a star is described as a spectral class G2V, we know that the star is similar to our Sun. We know its approximate mass, temperature, age, and size. When working with an extrasolar planet database, it is very useful to have a taxonomy scale (classification) such as, for example, the Harvard classification for stars. The taxonomy has to be easily interpreted and present the most relevant information about extrasolar planets. I propose an extrasolar planet taxonomy scale with four parameters. The first parameter concerns the mass of an extrasolar planet in the form of units of the mass of other known planets, where M represents the mass of Mercury, E that of Earth, N Neptune, and J Jupiter. The second parameter is the planet's distance from its parent star (semimajor axis) described in a logarithm with base 10. The third parameter is the mean Dyson temperature of the extrasolar planet, for which I established four main temperature classes: F represents the Freezing class, W the Water class, G the Gaseous class, and R the Roasters class. I devised one additional class, however: P, the Pulsar class, which concerns extrasolar planets orbiting pulsar stars. The fourth parameter is eccentricity. If the attributes of the surface of the extrasolar planet are known, we are able to establish this additional parameter where t represents a terrestrial planet, g a gaseous planet, and i an ice planet. According to this taxonomy scale, for example, Earth is 1E0W0t, Neptune is 1N1.5F0i, and extrasolar planet 55 Cnc e is 9E-1.8R1.

  8. The Frequency of Habitable Planets Around Small Stars and the Characterization of Planets Orbiting Bright Kepler Targets

    Science.gov (United States)

    Dressing, Courtney D.

    2015-01-01

    My thesis focuses on the frequency, detectability, and composition of small planets. I revised the parameters of the smallest Kepler main-sequence dwarf stars using Dartmouth Stellar Models and wrote a pipeline to search for planets in the full four-year Kepler data set. I characterized the completeness of my pipeline by injecting transiting planets and recording the fraction recovered. I refined the planet candidate sample by inspecting follow-up observations of planet host stars and correcting for transit depth dilution due to nearby stars. Accounting for possible false positive contamination, I estimated an occurrence rate of 0.2-0.8 potentially habitable planets per M dwarf; the variation in this estimated is dominated by the choice of habitable zone boundaries. For orbital periods conducted an adaptive optics imaging survey of 87 bright Kepler target stars with ARIES at the MMT to search for nearby stars that might be diluting the depths of the planetary transits. I identified visual companions within 1' for 5 targets, between 1' and 2' for 7 targets, and between 2' and 4' for 15 stars. For all stars observed, we placed limits on the presence of undetected nearby stars.Finally, I collaborated with the HARPS-N consortium to conduct an intensive observing campaign with the HARPS-N spectrograph at the Telescopio Nazionale Galileo in La Palma, Spain. We studied the Kepler-93 system, which contains a 1.4-Earth-radius planet in a 4.7-day orbit. Kepler-93b is a valuable addition to the exoplanet mass-radius diagram, as the physical parameters of the star have been accurately determined from asteroseismology. As a result, the size of the 1.4-Earth-radius transiting planet has been measured to an unprecedented precision of 120km (1.3%).

  9. Planet hunters. VI. An independent characterization of KOI-351 and several long period planet candidates from the Kepler archival data

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, Joseph R.; Wang, Ji; Fischer, Debra A.; Moriarty, John C.; Boyajian, Tabetha S. [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Jek, Kian J.; LaCourse, Daryll; Omohundro, Mark R.; Winarski, Troy; Goodman, Samuel Jon; Jebson, Tony; Schwengeler, Hans Martin; Paterson, David A.; Schwamb, Megan E. [Institute of Astronomy and Astrophysics, Academia Sinica, 11F of Astronomy-Mathematics Building, National Taiwan University. No.1, Sec. 4, Roosevelt Rd, Taipei 10617, Taiwan (China); Lintott, Chris; Simpson, Robert [Oxford Astrophysics, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Lynn, Stuart; Smith, Arfon M.; Parrish, Michael [Adler Planetarium, 1300 S. Lake Shore Drive, Chicago, IL 60605 (United States); Schawinski, Kevin, E-mail: joseph.schmitt@yale.edu [Institute for Astronomy, Department of Physics, ETH Zurich, Wolfgang-Pauli-Strasse 16, CH-8093 Zurich (Switzerland); and others

    2014-08-01

    We report the discovery of 14 new transiting planet candidates in the Kepler field from the Planet Hunters citizen science program. None of these candidates overlapped with Kepler Objects of Interest (KOIs) at the time of submission. We report the discovery of one more addition to the six planet candidate system around KOI-351, making it the only seven planet candidate system from Kepler. Additionally, KOI-351 bears some resemblance to our own solar system, with the inner five planets ranging from Earth to mini-Neptune radii and the outer planets being gas giants; however, this system is very compact, with all seven planet candidates orbiting ≲ 1 AU from their host star. A Hill stability test and an orbital integration of the system shows that the system is stable. Furthermore, we significantly add to the population of long period transiting planets; periods range from 124 to 904 days, eight of them more than one Earth year long. Seven of these 14 candidates reside in their host star's habitable zone.

  10. The Harsh Destiny of a Planet?

    Science.gov (United States)

    2001-05-01

    The VLT Uncovers Traces of Stellar Cannibalism Summary Did the star HD 82943 swallow one of its planets? What may at a first glance look like the recipe for a dramatic science-fiction story is in fact the well-considered conclusion of a serious scientific study, to be published by a group of astronomers in Switzerland and Spain [1] in tomorrow's issue of the international research journal "Nature". Using the very efficient UVES high-resolution spectrograph at the ESO VLT 8.2-m KUEYEN telescope , they have convincingly detected the presence of the rare isotope Lithium-6 ( 6 Li; [2]) in this metal-rich, solar-type dwarf star that is also known to possess a planetary system, cf. ESO Press Release 13/00. Unlike the Lithium-7 ( 7 Li) isotope of this light element, any primordial Lithium-6 would not survive the early evolutionary stages of a metal-rich solar-type star. The Lithium-6 now seen in HD 82943 must therefore have been added later, but from where? The astronomers believe that this observation strongly suggests that the star has at some moment engulfed one of its planets, whose Lithium-6 was then deposited in the star's atmosphere. This surprising discovery represents important observational evidence that planets may fall into their host stars. PR Photo 17/01 : The spectrum of HD 82943 with the Lithium absorption lines . Artist's impression (drawing and video) of the engulfment of a planet. HD 82943 and its planetary system The last few years have seen the discovery of more than 60 new planetary systems. One of the most prolific planet search programmes is being carried out by the Geneva Extra-Solar Planet Search Group , by means of the CORALIE spectrograph at the 1.2-m Leonard Euler Swiss Telescope at the ESO La Silla Observatory (Chile). One of the stars included in this programme is the dwarf star HD 82943 in the constellation Hydra (The Water Snake). It is slightly hotter and larger than the Sun and was recently found to harbour a planetary system with (at

  11. Watching How Planets Form

    Science.gov (United States)

    2006-09-01

    Anatomy of a Planet-Forming Disc around a Star More Massive than the Sun With the VISIR instrument on ESO's Very Large Telescope, astronomers have mapped the disc around a star more massive than the Sun. The very extended and flared disc most likely contains enough gas and dust to spawn planets. It appears as a precursor of debris discs such as the one around Vega-like stars and thus provides the rare opportunity to witness the conditions prevailing prior to or during planet formation. "Planets form in massive, gaseous and dusty proto-planetary discs that surround nascent stars. This process must be rather ubiquitous as more than 200 planets have now been found around stars other than the Sun," said Pierre-Olivier Lagage, from CEA Saclay (France) and leader of the team that carried out the observations. "However, very little is known about these discs, especially those around stars more massive than the Sun. Such stars are much more luminous and could have a large influence on their disc, possibly quickly destroying the inner part." The astronomers used the VISIR instrument [1] on ESO's Very Large Telescope to map in the infrared the disc surrounding the young star HD 97048. With an age of a few million years [2], HD 97048 belongs to the Chameleon I dark cloud, a stellar nursery 600 light-years away. The star is 40 times more luminous than our Sun and is 2.5 times as massive. The astronomers could only have achieved such a detailed view due to the high angular resolution offered by an 8-metre size telescope in the infrared, reaching a resolution of 0.33 arcsecond. They discovered a very large disc, at least 12 times more extended than the orbit of the farthest planet in the Solar System, Neptune. The observations suggest the disc to be flared. "This is the first time such a structure, predicted by some theoretical models, is imaged around a massive star," said Lagage. ESO PR Photo 36/06 ESO PR Photo 36/06 A Flared Proto-Planetary Disc Such a geometry can only be

  12. An International Asteroid Search Campaign: Internet-Based Hands-On Research Program for High Schools and Colleges, in Collaboration with the Hands-On Universe Project

    Science.gov (United States)

    Miller, J. Patrick; Davis, Jeffrey W.; Holmes, Robert E., Jr.; Devore, Harlan; Raab, Herbert; Pennypacker, Carlton R.; White, Graeme L.; Gould, Alan

    2008-01-01

    The International Asteroid Search Campaign (IASC, fondly nicknamed "Isaac") is an Internet-based program for high schools and colleges. Within hours of acquisition, astronomical CCD images are made available via the Internet to participating schools around the world. Under the guidance of their teachers, students analyze the images with free…

  13. An International Asteroid Search Campaign: Internet-Based Hands-On Research Program for High Schools and Colleges, in Collaboration with the Hands-On Universe Project

    Science.gov (United States)

    Miller, J. Patrick; Davis, Jeffrey W.; Holmes, Robert E., Jr.; Devore, Harlan; Raab, Herbert; Pennypacker, Carlton R.; White, Graeme L.; Gould, Alan

    2008-01-01

    The International Asteroid Search Campaign (IASC, fondly nicknamed "Isaac") is an Internet-based program for high schools and colleges. Within hours of acquisition, astronomical CCD images are made available via the Internet to participating schools around the world. Under the guidance of their teachers, students analyze the images with free…

  14. Prevalence of Earth-size Planets Orbiting Sun-like Stars

    Science.gov (United States)

    Petigura, Erik Ardeshir

    2015-04-01

    In this thesis, I explore two topics in exoplanet science. The first is the prevalence of Earth-size planets in the Milky Way Galaxy. To determine the occurrence of planets having different sizes, orbital periods, and other properties, I conducted a survey of extrasolar planets using data collected by NASA's Kepler Space Telescope. This project involved writing new algorithms to analyze Kepler data, finding planets, and conducting follow-up work using ground-based telescopes. I found that most stars have at least one planet at or within Earth's orbit and that 26% of Sun-like stars have an Earth-size planet with an orbital period of 100 days or less. The second topic is the connection between the properties of planets and their host stars. The precise characterization of exoplanet hosts helps to bring planet properties like mass, size, and equilibrium temperature into sharper focus and probes the physical processes that form planets. I studied the abundance of carbon and oxygen in over 1000 nearby stars using optical spectra taken by the California Planet Search. I found a large range in the relative abundance of carbon and oxygen in this sample, including a handful of carbon-rich stars. I also developed a new technique called SpecMatch for extracting fundamental stellar parameters from optical spectra. SpecMatch is particularly applicable to the relatively faint planet-hosting stars discovered by Kepler.

  15. Atmospheres of Extrasolar Giant Planets

    CERN Document Server

    Marley, M S; Seager, S; Barman, T; Marley, Mark S.; Fortney, Jonathan; Seager, Sara; Barman, Travis

    2006-01-01

    The key to understanding an extrasolar giant planet's spectrum--and hence its detectability and evolution--lies with its atmosphere. Now that direct observations of thermal emission from extrasolar giant planets are in hand, atmosphere models can be used to constrain atmospheric composition, thermal structure, and ultimately the formation and evolution of detected planets. We review the important physical processes that influence the atmospheric structure and evolution of extrasolar giant planets and consider what has already been learned from the first generation of observations and modeling. We pay particular attention to the roles of cloud structure, metallicity, and atmospheric chemistry in affecting detectable properties through Spitzer Space Telescope observations of the transiting giant planets. Our review stresses the uncertainties that ultimately limit our ability to interpret EGP observations. Finally we will conclude with a look to the future as characterization of multiple individual planets in a ...

  16. Atmospheres of Extrasolar Giant Planets

    Science.gov (United States)

    Marley, Mark

    2006-01-01

    The next decade will almost certainly see the direct imaging of extrasolar giant planets around nearby stars. Unlike purely radial velocity detections, direct imaging will open the door to characterizing the atmosphere and interiors of extrasola planets and ultimately provide clues on their formation and evolution through time. This process has already begun for the transiting planets, placing new constraints on their atmospheric structure, composition, and evolution. Indeed the key to understanding giant planet detectability, interpreting spectra, and constraining effective temperature and hence evolution-is the atmosphere. I will review the universe of extrasolar giant planet models, focusing on what we have already learned from modeling and what we will likely be able to learn from the first generation of direct detection data. In addition to these theoretical considerations, I will review the observations and interpretation of the - transiting hot Jupiters. These objects provide a test of our ability to model exotic atmospheres and challenge our current understanding of giant planet evolution.

  17. Planet Packing in Circumbinary Systems

    CERN Document Server

    Kratter, Kaitlin M

    2013-01-01

    The recent discovery of planets orbiting main sequence binaries will provide crucial constraints for theories of binary and planet formation. The formation pathway for these planets is complicated by uncertainties in the formation mechanism of the host stars. In this paper, we compare the dynamical states of single and binary star planetary systems. Specifically, we pose two questions: (1) What does it mean for a circumbinary system to be dynamically packed? (2) How many systems are required to differentiate between a population of packed or sparse planets? We determine when circumbinary systems become dynamically unstable as a function of the separation between the host-stars and the inner planet, and the first and second planets. We show that these represent unique stability constraints compared to single-star systems. We find that although the existing Kepler data is insufficient to distinguish between a population of packed or sparse circumbinary systems, a more thorough study of circumbinary TTVs combine...

  18. Bringing Planet Finder Closer: 1AU missions for Terrestrial Planet Finder, precursor and follow-on

    Science.gov (United States)

    Woolf, N. J.

    1997-12-01

    A mission to search for Earth-like planets and obtain their spectra was set at 5AU because the zodiacal dust emission at 1AU would make larger mirrors necessary. When the concept was developed in 1995, the Space Telescope with a 2.4m mirror cost \\2 billion. To ask for even larger mirrors on a mission seemed unrealistic. Now, Next Generation Space Telescope with a 6-8m glass membrane primary from the Mirror Lab seems achievable within budget, and a 1 AU Terrestrial Planet Finder mission with only half as much glass could be made at no greater cost. The advantages of a 1 AU mission are (1) further IR detector development would no longer be needed; (2) cryogens in dewars would last long enough; (3) for 1AU/5AU systems matched in performance for 15pc planets, the 1AU system would allow higher spectral resolution for closer planetary systems, possibly permitting detection of methane; (4) the signal /noise for a 1AU system will deteriorate less when a planetary system with strong exo-zodiacal emission is encountered; (5) neither RTGs nor large solar cell arrays are needed; (6) mass is less constrained. A precursor mission to confirm TPF techniques at lower cost, and study giant planets at 5\\mu$ could also operate at 1AU. A follow on mission to obtain high resolution spectra of exo-planetary atmospheres would not benefit appreciably from 5AU operation. A 1AU mission would be fine for it.

  19. Professor: The Animal Planet Optimization

    OpenAIRE

    Satish Gajawada

    2014-01-01

    This paper is dedicated to everyone who is interested in making this planet a better place to live. In the past, researchers have explored behavior of several animals separately. But there is scope to explore in the direction where various artificial animals together solve the optimization problem. In this paper, Satish Gajawada proposed The AnimalPlanet Optimization. The concept of this paper is to imitate all the animals on this planet. The idea is to solve the optimization problem where al...

  20. "Retired" Planet Hosts: Not So Massive, Maybe Just Portly After Lunch

    OpenAIRE

    Lloyd, James P.

    2011-01-01

    Studies of the planet abundance as a function of stellar mass have suggested a strong increase in the frequency of planet occurrence around stars more massive than $1.5 M_\\odot$, and that such stars are deficit in short period planets. These planet searches have relied on giant stars for a sample of high mass stars, which are hostile to precision Doppler measurements due to rotation and activity while on the main sequence. This paper considers the observed $v\\sin i$ and observationally inferr...