Science.gov

Sample records for exoplanet survey satellite

  1. Transiting Exoplanet Survey Satellite (TESS)

    NASA Technical Reports Server (NTRS)

    Ricker, G. R.; Clampin, M.; Latham, D. W.; Seager, S.; Vanderspek, R. K.; Villasenor, J. S.; Winn, J. N.

    2012-01-01

    The Transiting Exoplanet Survey Satellite (TESS) will discover thousands of exoplanets in orbit around the brightest stars in the sky. In a two-year survey, TESS will monitor more than 500,000 stars for temporary drops in brightness caused by planetary transits. This first-ever spaceborne all-sky transit survey will identify planets ranging from Earth-sized to gas giants, around a wide range of stellar types and orbital distances. No ground-based survey can achieve this feat. A large fraction of TESS target stars will be 30-100 times brighter than those observed by Kepler satellite, and therefore TESS . planets will be far easier to characterize with follow-up observations. TESS will make it possible to study the masses, sizes, densities, orbits, and atmospheres of a large cohort of small planets, including a sample of rocky worlds in the habitable zones of their host stars. TESS will provide prime targets for observation with the James Webb Space Telescope (JWST), as well as other large ground-based and space-based telescopes of the future. TESS data will be released with minimal delay (no proprietary period), inviting immediate community-wide efforts to study the new planets. The TESS legacy will be a catalog of the very nearest and brightest main-sequence stars hosting transiting exoplanets, thus providing future observers with the most favorable targets for detailed investigations.

  2. The Transiting Exoplanet Survey Satellite Mission

    NASA Astrophysics Data System (ADS)

    Ricker, G. R.

    2014-03-01

    The Transiting Exoplanet Survey Satellite (TESS) will discover thousands of exoplanets in orbit around the brightest stars in the sky. In a two-year survey of the solar neighborhood, TESS will monitor more than 500,000 stars for temporary drops in brightness caused by planetary transits. This first-ever spaceborne all-sky transit survey will identify planets ranging from Earth-sized to gas giants, around a wide range of stellar types and orbital distances. TESS stars will typically be 30-100 times brighter than those surveyed by the Kepler satellite; thus, TESS planets will be far easier to characterize with follow-up observations. For the first time it will be possible to study the masses, sizes, densities, orbits, and atmospheres of a large cohort of small planets, including a sample of rocky worlds in the habitable zones of their host stars. Full frame images with a cadence of 30 minutes or less will provide precise photometric information for several million stars during observation sessions of several weeks. The brighter TESS stars will potentially yield valuable asteroseismic information as a result of monitoring at a rapid cadence of 1 minute or less. An extended survey by TESS of the Ecliptic caps will provide prime exoplanet targets for characterization with the James Webb Space Telescope (JWST), as well as other large ground-based and space-based telescopes of the future. TESS will serve as the "People's Telescope," with data releases every 4 months, inviting immediate community-wide efforts to study the new planets. The TESS legacy will be a catalog of the nearest and brightest main-sequence stars hosting transiting exoplanets, which will endure as the most favorable targets for detailed future investigations. TESS has been selected by NASA for launch in 2017 as an Astrophysics Explorer mission.

  3. The Transiting Exoplanet Survey Satellite: Mission Status

    NASA Astrophysics Data System (ADS)

    Ricker, George R.; TESS Team

    2015-01-01

    The Transiting Exoplanet Survey Satellite (TESS) will discover thousands of exoplanets in orbit around the brightest stars in the sky. In a two-year survey of the solar neighborhood, TESS will monitor more than 200,000 bright stars for temporary drops in brightness caused by planetary transits. This first-ever spaceborne all-sky transit survey will identify planets ranging from Earth-sized to gas giants, around a wide range of stellar types and orbital distances.TESS stars will typically be 30-100 times brighter than those surveyed by the Kepler satellite; thus, TESS planets will be far easier to characterize with follow-up observations. For the first time it will be possible to study the masses, sizes, densities, orbits, and atmospheres of a large cohort of small planets, including a sample of rocky worlds in the habitable zones of their host stars. Full frame images with a cadence of 30 minutes or less will provide precise photometric information for more than 20 million stars during observation sessions of several weeks. The brighter TESS stars will potentially yield valuable asteroseismic information as a result of monitoring at a rapid cadence of 2 minute or less. An extended survey by TESS of regions surrounding the North and South Ecliptic Poles will provide prime exoplanet targets for characterization with the James Webb Space Telescope (JWST), as well as other large ground-based and space-based telescopes of the future.TESS will issue data releases every 4 months, inviting immediate community-wide efforts to study the new planets. The TESS legacy will be a catalog of the nearest and brightest main-sequence stars hosting transiting exoplanets, which will endure as the most favorable targets for detailed future investigations.TESS has a planned launch date in 2017 as a NASA Astrophysics Explorer mission.

  4. The Transiting Exoplanet Survey Satellite Mission

    NASA Astrophysics Data System (ADS)

    Ricker, George R.; Vanderspek, Roland Kraft; Latham, David W.; Winn, Joshua N.

    2014-06-01

    The Transiting Exoplanet Survey Satellite (TESS) will discover thousands of exoplanets in orbit around the brightest stars in the sky. In a two-year survey of the solar neighborhood, TESS will monitor more than 200,000 stars for temporary drops in brightness caused by planetary transits. This first-ever spaceborne all-sky transit survey will identify planets ranging from Earth-sized to gas giants, around a wide range of stellar types and orbital distances. TESS stars will typically be 30-100 times brighter than those surveyed by the Kepler satellite; thus, TESS planets will be far easier to characterize with follow-up observations. For the first time it will be possible to study the masses, sizes, densities, orbits, and atmospheres of a large cohort of small planets, including a sample of rocky worlds in the habitable zones of their host stars. Full frame images with a cadence of 30 minutes or less will provide precise photometric information for several million stars during observation sessions of several weeks. The brighter TESS stars will potentially yield valuable asteroseismic information as a result of monitoring at a rapid cadence of 1 minute or less. An extended survey by TESS of regions surrounding the North and South Ecliptic Poles will provide prime exoplanet targets for characterization with the James Webb Space Telescope (JWST), as well as other large ground-based and space-based telescopes of the future. TESS will serve as the “People’s Telescope,” with data releases every 4 months, inviting immediate community-wide efforts to study the new planets. The TESS legacy will be a catalog of the nearest and brightest main-sequence stars hosting transiting exoplanets, which will endure as the most favorable targets for detailed future investigations.TESS has been selected by NASA for launch in 2017 as an Astrophysics Explorer mission.

  5. The Transiting Exoplanet Survey Satellite Mission

    NASA Astrophysics Data System (ADS)

    Ricker, G. R.

    2014-06-01

    (Abstract only) The Transiting Exoplanet Survey Satellite (TESS) will discover thousands of exoplanets in orbit around the brightest stars in the sky. In a two-year survey of the solar neighborhood, TESS will monitor more than 500,000 stars for temporary drops in brightness caused by planetary transits. This first-ever spaceborne all-sky transit survey will identify planets ranging from Earth-sized to gas giants, around a wide range of stellar types and orbital distances. TESS stars will typically be 30 to 100 times brighter than those surveyed by the Kepler satellite; thus,TESS planets will be far easier to characterize with follow-up observations. For the first time it will be possible to study the masses, sizes, densities, orbits, and atmospheres of a large cohort of small planets, including a sample of rocky worlds in the habitable zones of their host stars. All of the half-million plus TESS targets will be observed at a rapid cadence (1 minute or less). Hence, the brighter TESS stars will potentially yield valuable asteroseismic information. TESS will provide prime exoplanet targets for characterization with the James Webb Space Telescope (JWST), as well as other large ground-based and space-based telescopes of the future. TESS will serve as the "People's Telescope," with data releases every 4 months, inviting immediate community-wide efforts to study the new planets. The TESS legacy will be a catalog of the nearest and brightest main-sequence stars hosting transiting exoplanets, which will endure as the most favorable targets for detailed future investigations. TESS has been selected by NASA for launch in 2017 as an Astrophysics Explorer mission.

  6. Trajectory Design for the Transiting Exoplanet Survey Satellite

    NASA Technical Reports Server (NTRS)

    Dichmann, Donald J.; Parker, Joel J. K.; Williams, Trevor W.; Mendelsohn, Chad R.

    2014-01-01

    The Transiting Exoplanet Survey Satellite (TESS) is a National Aeronautics and Space Administration (NASA) mission, scheduled to be launched in 2017. TESS will travel in a highly eccentric orbit around Earth, with initial perigee radius near 17 Earth radii (Re) and apogee radius near 59 Re. The orbit period is near 2:1 resonance with the Moon, with apogee nearly 90 degrees out-of-phase with the Moon, in a configuration that has been shown to be operationally stable. TESS will execute phasing loops followed by a lunar flyby, with a final maneuver to achieve 2:1 resonance with the Moon. The goals of a resonant orbit with long-term stability, short eclipses and limited oscillations of perigee present significant challenges to the trajectory design. To rapidly assess launch opportunities, we adapted the Schematics Window Methodology (SWM76) launch window analysis tool to assess the TESS mission constraints. To understand the long-term dynamics of such a resonant orbit in the Earth-Moon system we employed Dynamical Systems Theory in the Circular Restricted 3-Body Problem (CR3BP). For precise trajectory analysis we use a high-fidelity model and multiple shooting in the General Mission Analysis Tool (GMAT) to optimize the maneuver delta-V and meet mission constraints. Finally we describe how the techniques we have developed can be applied to missions with similar requirements. Keywords: resonant orbit, stability, lunar flyby, phasing loops, trajectory optimization

  7. Trajectory Design for the Transiting Exoplanet Survey Satellite (TESS)

    NASA Technical Reports Server (NTRS)

    Dichmann, Donald J.; Parker, Joel; Williams, Trevor; Mendelsohn, Chad

    2014-01-01

    The Transiting Exoplanet Survey Satellite (TESS) is a National Aeronautics and Space Administration (NASA) mission launching in 2017. TESS will travel in a highly eccentric orbit around Earth, with initial perigee radius near 17 Earth radii (Re) and apogee radius near 59 Re. The orbit period is near 2:1 resonance with the Moon, with apogee nearly 90 degrees out-of-phase with the Moon, in a configuration that has been shown to be operationally stable. TESS will execute phasing loops followed by a lunar flyby, with a final maneuver to achieve 2:1 resonance with the Moon. The goals of a resonant orbit with long-term stability, short eclipses and limited oscillations of perigee present significant challenges to the trajectory design. To rapidly assess launch opportunities, we adapted the SWM76 launch window tool to assess the TESS mission constraints. To understand the long-term dynamics of such a resonant orbit in the Earth-Moon system we employed Dynamical Systems Theory in the Circular Restricted 3-Body Problem (CR3BP). For precise trajectory analysis we use a high-fidelity model and multiple shooting in the General Mission Analysis Tool (GMAT) to optimize the maneuver delta-V and meet mission constraints. Finally we describe how the techniques we have developed can be applied to missions with similar requirements.

  8. The Guest Investigator Program for the Transiting Exoplanet Survey Satellite (TESS)

    NASA Astrophysics Data System (ADS)

    Rinehart, Stephen; Ricker, George R.; Seager, Sara; Latham, David W.; Kraft Vanderspek, Roland; Winn, Joshua N.

    2016-01-01

    Over the summer of 2015, NASA HQ approved the establishment of a Guest Investigator (GI) Program for the Transiting Exoplanet Survey Satellite (TESS). This office, being established at NASA's Goddard Space Flight Center, will provide support to the Astronomical Community for working with data from the TESS mission. In this presentation, we discuss the overall structure and plan for the GI program, and show the schedule for Community involvement.

  9. Scientific, Back-Illuminated CCD Development for the Transiting Exoplanet Survey Satellite

    NASA Technical Reports Server (NTRS)

    Suntharalingam, V.; Ciampi, J.; Cooper, M. J.; Lambert, R. D.; O'Mara, D. M.; Prigozhin, I.; Young, D. J.; Warner, K.; Burke, B. E.

    2015-01-01

    We describe the development of the fully depleted, back illuminated charge coupled devices for the Transiting Exoplanet Survey Satellite, which includes a set of four wide angle telescopes, each having a 2x2 array of CCDs. The devices are fabricated on the newly upgraded 200-mm wafer line at Lincoln Laboratory. We discuss methods used to produce the devices and present early performance results from the 100- micron thick, 15x15-microns, 2k x 4k pixel frame transfer CCDs.

  10. Trajectory Design Enhancements to Mitigate Risk for the Transiting Exoplanet Survey Satellite (TESS)

    NASA Technical Reports Server (NTRS)

    Dichmann, Donald; Parker, Joel; Nickel, Craig; Lutz, Stephen

    2016-01-01

    The Transiting Exoplanet Survey Satellite (TESS) will employ a highly eccentric Earth orbit, in 2:1 lunar resonance, which will be reached with a lunar flyby preceded by 3.5 phasing loops. The TESS mission has limited propellant and several constraints on the science orbit and on the phasing loops. Based on analysis and simulation, we have designed the phasing loops to reduce delta-V (DV) and to mitigate risk due to maneuver execution errors. We have automated the trajectory design process and use distributed processing to generate and optimal nominal trajectories; to check constraint satisfaction; and finally to model the effects of maneuver errors to identify trajectories that best meet the mission requirements.

  11. The Transiting Exoplanet Survey Satellite (TESS): Discovering New Earths and Super-Earths in the Solar Neighborhood

    NASA Astrophysics Data System (ADS)

    Ricker, George R.

    2015-12-01

    The Transiting Exoplanet Survey Satellite (TESS) will discover thousands of exoplanets in orbit around the brightest stars in the sky. In its two-year prime survey mission, TESS will monitor more than 200,000 bright stars in the solar neighborhood for temporary drops in brightness caused by planetary transits. This first-ever spaceborne all-sky transit survey will identify planets ranging from Earth-sized to gas giants, around a wide range of stellar types and orbital distances.TESS stars will typically be 30-100 times brighter than those surveyed by the Kepler satellite; thus, TESS planets will be far easier to characterize with follow-up observations. For the first time it will be possible to study the masses, sizes, densities, orbits, and atmospheres of a large cohort of small planets, including a sample of rocky worlds in the habitable zones of their host stars.An additional data product from the TESS mission will be full frame images (FFI) with a cadence of 30 minutes or less. These FFI will provide precise photometric information for every object within the 2300 square degree instantaneous field of view of the TESS cameras. These objects will include more than 1 million stars and bright galaxies observed during sessions of several weeks. In total, more than 30 million objects brighter than I=16 will be precisely photometered during the two-year prime mission. In principle, the lunar-resonant TESS orbit could provide opportunities for an extended mission lasting more than a decade, with data rates in excess of 100 Mbits/s.An extended survey by TESS of regions surrounding the North and South Ecliptic Poles will provide prime exoplanet targets for characterization with the James Webb Space Telescope (JWST), as well as other large ground-based and space-based telescopes of the future.TESS will issue data releases every 4 months, inviting immediate community-wide efforts to study the new planets, as well as commensal survey candidates from the FFI. A NASA Guest

  12. Thermal Design of the Instrument for the Transiting Exoplanet Survey Satellite

    NASA Technical Reports Server (NTRS)

    Allen, Gregory D.

    2016-01-01

    TESS observatory is a two year NASA Explorer mission which will use a set of four cameras to discover exoplanets. It will be placed in a high-earth orbit with a period of 13.7 days and will be unaffected by temperature disturbances caused by environmental heating from the Earth. The cameras use their stray-light baffles to passively cool the cameras and in turn the CCD's in order to maintain operational temperatures. The design has been well thought out and analyzed to maximize temperature stability. The analysis shows that the design keeps the cameras and their components within their temperature ranges which will help make it a successful mission. It will also meet its survival requirement of sustaining exposure to a five hour eclipse. Official validation and verification planning is underway and will be performed as the system is built up. It is slated for launch in 2017.

  13. CHEOPS: CHaracterising ExOPlanet Satellite

    NASA Astrophysics Data System (ADS)

    Isaak, K. G.

    2015-10-01

    CHEOPS (CHaracterising ExOPlanet Satellite) is the first exoplanet mission dedicated to the search for transits of exoplanets by means of ultrahigh precision photometry of bright stars already known to host planets. CHEOPS will provide the unique capability of determining radii to ~10% accuracy for a subset of those planets in the super-Earth to Neptune mass range. The high photometric precision of CHEOPS will be achieved using a photometer covering the 0.4 - 1.1um waveband and designed around a single frame-transfer CCD which is mounted in the focal plane of a 30 cm equivalent aperture diameter, f/5 on-axis Ritchey-Chretien telescope. Key to reaching the required performance is rejection of straylight from the Earth that is achieved using a specially designed optical baffle. CHEOPS is the first S-class mission in ESA's Cosmic Vision 2015-2025, and is currently planned to be launch-ready by the end of 2017. The mission is a partnership between Switzerland and ESA's science programme, with important contributions from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden and the United Kingdom. In this presentation I will give a scientific and technical overview of the mission, as well as an update on the status of the project.

  14. Transiting Exoplanet Survey Satellite (TESS) Community Observer Program including the Science Enhancement Option Box (SEO Box) - 12 TB On-board Flash Memory for Serendipitous Science

    NASA Astrophysics Data System (ADS)

    Schingler, Robert; Villasenor, J. N.; Ricker, G. R.; Latham, D. W.; Vanderspek, R. K.; Ennico, K. A.; Lewis, B. S.; Bakos, G.; Brown, T. M.; Burgasser, A. J.; Charbonneau, D.; Clampin, M.; Deming, L. D.; Doty, J. P.; Dunham, E. W.; Elliot, J. L.; Holman, M. J.; Ida, S.; Jenkins, J. M.; Jernigan, J. G.; Kawai, N.; Laughlin, G. P.; Lissauer, J. J.; Martel, F.; Sasselov, D. D.; Seager, S.; Torres, G.; Udry, S.; Winn, J. N.; Worden, S. P.

    2010-01-01

    The Transiting Exoplanet Survey Satellite (TESS) will perform an all-sky survey in a low-inclination, low-Earth orbit. TESS's 144 GB of raw data collected each orbit will be stacked, cleaned, cut, compressed and downloaded. The Community Observer Program is a Science Enhancement Option (SEO) that takes advantage of the low-radiation environment, technology advances in flash memory, and the vast amount of astronomical data collected by TESS. The Community Observer Program requires the addition of a 12 TB "SEO Box” inside the TESS Bus. The hardware can be built using low-cost Commercial Off-The-Shelf (COTS) components and fits within TESS's margins while accommodating GSFC gold rules. The SEO Box collects and stores a duplicate of the TESS camera data at a "raw” stage ( 4.3 GB/orbit, after stacking and cleaning) and makes them available for on-board processing. The sheer amount of onboard storage provided by the SEO Box allows the stacking and storing of several months of data, allowing the investigator to probe deeper in time prior to a given event. Additionally, with computation power and data in standard formats, investigators can utilize data-mining techniques to investigate serendipitous phenomenon, including pulsating stars, eclipsing binaries, supernovae or other transient phenomena. The Community Observer Program enables ad-hoc teams of citizen scientists to propose, test, refine and rank algorithms for on-board analysis to support serendipitous science. Combining "best practices” of online collaboration, with careful moderation and community management, enables this `crowd sourced’ participatory exploration with a minimal risk and impact on the core TESS Team. This system provides a powerful and independent tool opening a wide range of opportunity for science enhancement and secondary science. Support for this work has been provided by NASA, the Kavli Foundation, Google, and the Smithsonian Institution.

  15. TMT and Exoplanet Radial Velocity Surveys

    NASA Astrophysics Data System (ADS)

    Tanner, Angelle; Crossfield, Ian

    2014-07-01

    With echelle spectrometers on the verge of crossing over the 0.1 m/s radial velocity (RV) measurement precision threshold needed to detect habitable Earth mass planets around Sun-like stars, conducing such surveys on state-of-the-art telescopes is an imperative. RV exoplanets surveys conducted with the optical and infrared echelle spectrometers being built for the TMT have the potential to complete a census of the population of Earth-mass planets in our local stellar neighborhood. The detection of such systems will provide a valuable stellar sample for follow-up exoplanet studies which would characterize the atmospheres of these or additional planets found in these nearby solar systems. Here, we will further discuss the impact of the TMT on radial velocity exoplanet surveys.

  16. Exoplanets in the M2K Survey

    NASA Astrophysics Data System (ADS)

    Boyajian, Tabetha; Fischer, Debra; Gaidos, Eric; Giguere, Matt

    2013-07-01

    Late type stars are ideal targets for the detection of low-mass planets residing in habitable zones. In such systems, not only is the stellar noise a minimum, but the lower stellar mass affords larger reflex velocities and the lower stellar luminosity moves the habitable zone inward. The M2K program is a high precision Doppler survey monitoring a couple hundred late-type stars over the past few years in search for such important exoplanetary systems. We present updated orbits of known exoplanet systems and newly detected exoplanet systems that have resulted from this program. We also advertise the Planethunters.org "Guest Scientist" program as well as our survey to measure stellar diameters and temperatures with long baseline optical interferometry.

  17. The Gemini Planet Imager Exoplanet Survey

    NASA Astrophysics Data System (ADS)

    Macintosh, Bruce

    The Gemini Planet Imager (GPI) is a next-generation coronagraph constructed for the Gemini Observatory. GPI will see first light this fall. It will be the most advanced planet-imaging system in operation - an order of magnitude more sensitive than any current instrument, capable of detecting and spectroscopically characterizing young Jovian planets 107 times fainter than their parent star at separations of 0.2 arcseconds. GPI was built from the beginning as a facility-class survey instrument, and the observatory will employ it that way. Our team has been selected by Gemini Observatory to carry out an 890-hour program - the GPI Exoplanet Survey (GPIES) campaign from 2014-2017. We will observe 600 stars spanning spectral types A-M. We will use published young association catalogs and a proprietary list in preparation that adds several hundred new young (<100 Myr, <75 pc) and adolescent (<300 Myr, <35 pc) stars. The range of separations studied by GPI is completely inaccessible to Doppler and transit techniques (even with Kepler or TESS)— GPI offers a new window into planet formation. We will use GPI to produce the first-ever robust census of giant planet populations in the 5-50 AU range, allowing us to: 1) illuminate the formation pathways of Jovian planets; 2) reconstruct the early dynamical evolution of systems, including migration mechanisms and the interaction with disks and belts of debris; and 3) bridge the gap between Jupiter and the brown dwarfs with the first examples of cool low- gravity planetary atmospheres. Simulations predict this survey will discover approximately 50 exoplanets, increasing the number of exoplanet images by an order of magnitude, enough for statistical investigation. This Origins of Solar Systems proposal will support the execution of the GPI Exoplanet Survey campaign. We will develop tools needed to execute the survey efficiently. We will refine the existing GPI data pipeline to a final version that robustly removes residual speckle

  18. Exoplanets

    NASA Astrophysics Data System (ADS)

    Seager, S.

    2010-12-01

    This is a unique time in human history - for the first time, we are on the technological brink of being able to answer questions that have been around for thousands of years: Are there other planets like Earth? Are they common? Do any have signs of life? The field of exoplanets is rapidly moving toward answering these questions with the discovery of hundreds of exoplanets now pushing toward lower and lower masses; the Kepler Space Telescope with its yield of small planets; plans to use the James Webb Space Telescope (launch date 2014) to study atmospheres of a subset of super Earths; and ongoing development for technology to directly image true Earth analogs. Theoretical studies in dynamics, planet formation, and physical characteristics provide the needed framework for prediction and interpretation. People working outside of exoplanets often ask if the field of exoplanets is like a dot.com bubble that will burst, deflating excitement and progress. In my opinion, exciting discoveries and theoretical advances will continue indefinitely in the years ahead, albeit at a slower pace than in the first decade. The reason is that observations uncover new kinds and new populations of exoplanets -- and these observations rely on technological development that usually takes over a decade to mature. For example, in the early 2000s all but one exoplanet was discovered by the radial velocity technique. At that time, many groups around the world were working on wide-field transit surveys. But it was not until recently, a decade into the twenty-first century, that the transit technique is responsible for almost one-quarter of known exoplanets. The planet discovery techniques astrometry (as yet to find a planet) and direct imaging have not yet matured; when they do, they will uncover planets within a new parameter space of planet mass and orbital characteristics. In addition, people are working hard to improve the precision for existing planet discovery techniques to detect lower

  19. Exoplanets

    NASA Astrophysics Data System (ADS)

    Seager, S.

    2010-12-01

    This is a unique time in human history - for the first time, we are on the technological brink of being able to answer questions that have been around for thousands of years: Are there other planets like Earth? Are they common? Do any have signs of life? The field of exoplanets is rapidly moving toward answering these questions with the discovery of hundreds of exoplanets now pushing toward lower and lower masses; the Kepler Space Telescope with its yield of small planets; plans to use the James Webb Space Telescope (launch date 2014) to study atmospheres of a subset of super Earths; and ongoing development for technology to directly image true Earth analogs. Theoretical studies in dynamics, planet formation, and physical characteristics provide the needed framework for prediction and interpretation. People working outside of exoplanets often ask if the field of exoplanets is like a dot.com bubble that will burst, deflating excitement and progress. In my opinion, exciting discoveries and theoretical advances will continue indefinitely in the years ahead, albeit at a slower pace than in the first decade. The reason is that observations uncover new kinds and new populations of exoplanets -- and these observations rely on technological development that usually takes over a decade to mature. For example, in the early 2000s all but one exoplanet was discovered by the radial velocity technique. At that time, many groups around the world were working on wide-field transit surveys. But it was not until recently, a decade into the twenty-first century, that the transit technique is responsible for almost one-quarter of known exoplanets. The planet discovery techniques astrometry (as yet to find a planet) and direct imaging have not yet matured; when they do, they will uncover planets within a new parameter space of planet mass and orbital characteristics. In addition, people are working hard to improve the precision for existing planet discovery techniques to detect lower

  20. Subaru SEEDS Survey of Exoplanets and Disks

    NASA Technical Reports Server (NTRS)

    McElwain, Michael W.

    2012-01-01

    The Strategic Exploration of Exoplanets and Disks at Subaru (SEEDS) is the first strategic observing program (SSOPs) awarded by the National Astronomical Observatory of Japan (NAOJ). SEEDS targets a broad sample of stars that span a wide range of masses and ages to explore the formation and evolution of planetary systems. This survey has been awarded 120 nights over five years time to observe nearly 500 stars. Currently in the second year, SEEDS has already produced exciting new results for the protoplanetary disk AB Aur, transitional disk LkCa15, and nearby companion to GJ 758. We present the survey architecture, performance, recent results, and the projected sample. Finally, we will discuss planned upgrades to the high contrast instrumentation at the Subaru Telescope

  1. COMPLETENESS OF IMAGING SURVEYS FOR ECCENTRIC EXOPLANETS

    SciTech Connect

    Kane, Stephen R.

    2013-03-20

    The detection of exoplanets through direct imaging has produced numerous new positive identifications in recent years. The technique is biased toward planets at wide separations due to the difficulty in removing the stellar signature at small angular separations. Planets in eccentric orbits will thus move in and out of the detectable region around a star as a function of time. Here we use the known diversity of orbital eccentricities to determine the range of orbits that may lie beneath the detection threshold of current surveys. We quantify the percentage of the orbit that yields a detectable signature as a function of semimajor axis, eccentricity, and orbital inclination and estimate the fraction of planets which likely remain hidden by the flux of the host star.

  2. MASSIVE SATELLITES OF CLOSE-IN GAS GIANT EXOPLANETS

    SciTech Connect

    Cassidy, Timothy A.; Johnson, Robert E.; Mendez, Rolando; Arras, Phil; Skrutskie, Michael F. E-mail: rem5d@cms.mail.virginia.ed E-mail: rej@virginia.ed

    2009-10-20

    We study the orbits, tidal heating and mass loss from satellites around close-in gas giant exoplanets. The focus is on large satellites which are potentially observable by their transit signature. We argue that even Earth-size satellites around hot Jupiters can be immune to destruction by orbital decay; detection of such a massive satellite would strongly constrain theories of tidal dissipation in gas giants, in a manner complementary to orbital circularization. The star's gravity induces significant periodic eccentricity in the satellite's orbit. The resulting tidal heating rates, per unit mass, are far in excess of Io's and dominate radioactive heating out to planet orbital periods of months for reasonable satellite tidal Q. Inside planet orbital periods of about a week, tidal heating can completely melt the satellite. Lastly, we compute an upper limit to the satellite mass loss rate due to thermal evaporation from the surface, valid if the satellite's atmosphere is thin and vapor pressure is negligible. Using this upper limit, we find that although rocky satellites around hot Jupiters with orbital periods less than a few days can be significantly evaporated in their lifetimes, detectable satellites suffer negligible mass loss at longer orbital periods.

  3. Astrometric exoplanet surveys in practice: challenges, opportunities, and results

    NASA Astrophysics Data System (ADS)

    Sahlmann, Johannes

    2015-08-01

    Conversely to the transit photometry and radial velocity methods, the astrometric discovery of exoplanets is still limited by the sensitivity of available instruments. Furthermore, the signature of a planet (described by 7 free parameters) is orders of magnitude smaller than the standard motion of a star (5 free parameters), which has to be solved for first. This has important implications in the design and implementation of astrometric planet search surveys and the large parameter space to be explored calls for efficient fitting algorithms. I will present results of the so-far most precise astrometric planet search from the ground, targeting 20 very low-mass stars and brown dwarfs with an accuracy of 100 micro-arcseconds, which include the discovery of binaries with components in the planetary mass regime and several planet candidates with Neptune-to-Jupiter masses. The employed genetic and MCMC algorithms were shown to be efficient in constraining all astrometric parameters, which makes them important tools for the exploitation of the data currently collected by the Gaia satellite. Gaia is expected to astrometrically discover thousands of giant exoplanets and I will report on several ongoing projects in preparation of this unique harvest, including the expected yield of circumbinary planets.

  4. The Orbital Design of Alpha Centauri Exoplanet Satellite (ACESat)

    NASA Technical Reports Server (NTRS)

    Weston, Sasha; Belikov, Rus; Bendek, Eduardo

    2015-01-01

    Exoplanet candidates discovered by Kepler are too distant for biomarkers to be detected with foreseeable technology. Alpha Centauri has high separation from other stars and is of close proximity to Earth, which makes the binary star system 'low hanging fruit' for scientists. Alpha Centauri Exoplanet Satellite (ACESat) is a mission proposed to Small Explorer Program (SMEX) that will use a coronagraph to search for an orbiting planet around one of the stars of Alpha Centauri. The trajectory design for this mission is presented here where three different trajectories are considered: Low Earth Orbit (LEO), Geosynchronous Orbit (GEO) and a Heliocentric Orbit. Uninterrupted stare time to Alpha Centauri is desirable for meeting science requirements, or an orbit that provides 90% stare time to the science target. The instrument thermal stability also has stringent requirements for proper function, influencing trajectory design.

  5. Follow The Water: The Ultimate WFC3 Exoplanet Atmosphere Survey

    NASA Astrophysics Data System (ADS)

    Bean, Jacob

    2013-10-01

    Recent surveys have revealed an amazing, and yet unexplained, diversity of planets orbiting other stars. Studying the atmospheres of representative exoplanets is the key next step in leveraging these detections to further transform our understanding of planet formation and planetary physics. This is because a planet's atmosphere is a fossil record of its primordial origins and controls its size and appearance.We propose an intensive and comprehensive exoplanet atmosphere Large Treasury survey using the unrivaled capabilities of the WFC3 IR instrument to measure high-precision transmission, dayside emission, and phase-resolved emission spectra over a broad wavelength range for eight planetary Rosetta Stones. These data will yield unprecedented constraints on the abundances of water, elemental abundance ratios, thermal profiles, chemistries, presence of clouds and hazes, and dynamics of exoplanet atmospheres. Just detecting the atmospheres of these planets is not enough anymore. Revealing the fundamental properties of exoplanet atmospheres to investigate their nature and origins requires high-precision spectroscopy that is sensitive to spectral features from multiple chemical species and altitudes, and such data can only be obtained with an intensive HST program. A survey is mandatory to put the individual objects in a broader context, and to get at the underlying physics that results in a diverse array of emergent properties. This Treasury program will have no proprietary period in order to accelerate the progress of the field. This program is urgently needed to prepare for the future characterization of habitable exoplanets using JWST.

  6. Statistical Signatures of Panspermia in Exoplanet Surveys

    NASA Astrophysics Data System (ADS)

    Lin, Henry W.; Loeb, Abraham

    2015-09-01

    A fundamental astrobiological question is whether life can be transported between extrasolar systems. We propose a new strategy to answer this question based on the principle that life which arose via spreading will exhibit more clustering than life which arose spontaneously. We develop simple statistical models of panspermia to illustrate observable consequences of these excess correlations. Future searches for biosignatures in the atmospheres of exoplanets could test these predictions: a smoking gun signature of panspermia would be the detection of large regions in the Milky Way where life saturates its environment interspersed with voids where life is very uncommon. In a favorable scenario, detection of as few as ∼25 biologically active exoplanets could yield a 5σ detection of panspermia. Detectability of position-space correlations is possible unless the timescale for life to become observable once seeded is longer than the timescale for stars to redistribute in the Milky Way.

  7. The exoplanet microlensing survey by the proposed WFIRST Observatory

    NASA Astrophysics Data System (ADS)

    Barry, Richard; Kruk, Jeffery; Anderson, Jay; Beaulieu, Jean-Philippe; Bennett, David P.; Catanzarite, Joseph; Cheng, Ed; Gaudi, Scott; Gehrels, Neil; Kane, Stephen; Lunine, Jonathan; Sumi, Takahiro; Tanner, Angelle; Traub, Wesley

    2011-10-01

    The New Worlds, New Horizons report released by the Astronomy and Astrophysics Decadal Survey Board in 2010 listed the Wide Field Infrared Survey Telescope (WFIRST) as the highest-priority large space mission for the coming decade. This observatory will provide wide-field imaging and slitless spectroscopy at near infrared wavelengths. The scientific goals are to obtain a statistical census of exoplanets using gravitational microlensing, measure the expansion history of and the growth of structure in the Universe by multiple methods, and perform other astronomical surveys to be selected through a guest observer program. A Science Definition Team has been established to assist NASA in the development of a Design Reference Mission that accomplishes this diverse array of science programs with a single observatory. In this paper we present the current WFIRST payload concept and the expected capabilities for planet detection. The observatory, with science goals that are complimentary to the Kepler exoplanet transit mission, is designed to complete the statistical census of planetary systems in the Galaxy, from habitable Earth-mass planets to free floating planets, including analogs to all of the planets in our Solar System except Mercury. The exoplanet microlensing survey will observe for 500 days spanning 5 years. This long temporal baseline will enable the determination of the masses for most detected exoplanets down to 0.1 Earth masses.

  8. The Exoplanet Microlensing Survey by the Proposed WFIRST Observatory

    NASA Technical Reports Server (NTRS)

    Barry, Richard; Kruk, Jeffrey; Anderson, Jay; Beaulieu, Jean-Philippe; Bennett, David P.; Catanzarite, Joseph; Cheng, Ed; Gaudi, Scott; Gehrels, Neil; Kane, Stephen; Lunine, Jonathan; Sumi, Takahiro; Tanner, Angelle; Traub, Wesley

    2012-01-01

    The New Worlds, New Horizons report released by the Astronomy and Astrophysics Decadal Survey Board in 2010 listed the Wide Field Infrared Survey Telescope (WFIRST) as the highest-priority large space mission for the . coming decade. This observatory will provide wide-field imaging and slitless spectroscopy at near infrared wavelengths. The scientific goals are to obtain a statistical census of exoplanets using gravitational microlensing. measure the expansion history of and the growth of structure in the Universe by multiple methods, and perform other astronomical surveys to be selected through a guest observer program. A Science Definition Team has been established to assist NASA in the development of a Design Reference Mission that accomplishes this diverse array of science programs with a single observatory. In this paper we present the current WFIRST payload concept and the expected capabilities for planet detection. The observatory. with science goals that are complimentary to the Kepler exoplanet transit mission, is designed to complete the statistical census of planetary systems in the Galaxy, from habitable Earth-mass planets to free floating planets, including analogs to all of the planets in our Solar System except Mercury. The exoplanet microlensing survey will observe for 500 days spanning 5 years. This long temporal baseline will enable the determination of the masses for most detected exoplanets down to 0.1 Earth masses.

  9. Scheduling the EChO survey with known exoplanets

    NASA Astrophysics Data System (ADS)

    Morales, J. C.; Beaulieu, J.-P.; Coudé du Foresto, V.; Ollivier, M.; Castello, I. Ortega; Clédassou, R.; Jaubert, J.; Van-Troostenberghe, P.; Varley, R.; Waldmann, I. P.; Pascale, E.; Tessenyi, M.

    2015-12-01

    The Exoplanet Characterization Observatory ( EChO) is a concept of a dedicated space telescope optimized for low-resolution transit and occultation spectroscopy to study the exoplanet diversity through the composition of their atmospheres. The scope of this paper is to answer the following question: Can we schedule a nominal EChO mission, with targets known today (in mid 2013), given the science requirements, realistic performances and operational constraints? We examine this issue from the point of view of duration of the mission and the scheduling restrictions with a sample of exoplanet systems known nowadays. We choose different scheduling algorithms taking into account the science and operational constraints and we verified that it is fairly straightforward to schedule a mission scenario over the lifetime of EChO compliant with the science requirements. We identified agility as a critical constraint that reduces significantly the efficiency of the survey. We conclude that even with known targets today the EChO science objectives can be reached in the 4.5 years duration of the mission. We also show that it is possible to use gaps between exoplanet observations, to fit the required calibration observations, data downlinks and station keeping operations or even to observe more exoplanet targets to be discovered in the coming years.

  10. ACCESS: The Arizona-CfA-Catolica Exoplanet Spectroscopy Survey

    NASA Astrophysics Data System (ADS)

    Lopez-Morales, Mercedes; Apai, Daniel; Jordan, Andres; Espinoza, Nestor; Rackham, Benjamin; Fraine, Jonathan D.; Rodler, Florian; Lewis, Nikole; Fortney, Jonathan J.; Osip, David J.

    2014-06-01

    The Arizona-CfA-Catolica Exoplanet Spectroscopy Survey (ACCESS) is an international, multi-institutional consortium with members from the Harvard-Smithsonian CfA, the University of Arizona, Pontificia Universidad Catolica in Chile, MIT and UC Santa Cruz and the Carnegie Institution. ACCESS' goal is to observe about two dozen planets covering a wide range of mass, radius, atmospheric temperatures and energy irradiation levels, with two main scientific goals: 1) to obtain, for the first time, a uniform sample of visible transmission spectra of exoplanets, allowing the study of their atmospheric characteristics as a statistically significant sample, and 2) to mature the technique of ground-based observations of exoplanetary atmospheres for future observations of small planets. Here we describe ACCESS and its first science results.

  11. Faint detection of exoplanets in microlensing surveys

    SciTech Connect

    Brown, Robert A.

    2014-06-20

    We propose a new approach to discovering faint microlensing signals below traditional thresholds, and for estimating the binary-lens mass ratio and the apparent separation from such signals. The events found will be helpful in accurately estimating the true distribution of planetary semimajor axes, which is an important goal of space microlensing surveys.

  12. Design Considerations: Falcon M Dwarf Habitable Exoplanet Survey

    NASA Astrophysics Data System (ADS)

    Polsgrove, Daniel; Novotny, Steven; Della-Rose, Devin J.; Chun, Francis; Tippets, Roger; O'Shea, Patrick; Miller, Matthew

    2016-01-01

    The Falcon Telescope Network (FTN) is an assemblage of twelve automated 20-inch telescopes positioned around the globe, controlled from the Cadet Space Operations Center (CSOC) at the US Air Force Academy (USAFA) in Colorado Springs, Colorado. Five of the 12 sites are currently installed, with full operational capability expected by the end of 2016. Though optimized for studying near-earth objects to accomplish its primary mission of Space Situational Awareness (SSA), the Falcon telescopes are in many ways similar to those used by ongoing and planned exoplanet transit surveys targeting individual M dwarf stars (e.g., MEarth, APACHE, SPECULOOS). The network's worldwide geographic distribution provides additional potential advantages. We have performed analytical and empirical studies exploring the viability of employing the FTN for a future survey of nearby late-type M dwarfs tailored to detect transits of 1-2REarth exoplanets in habitable-zone orbits . We present empirical results on photometric precision derived from data collected with multiple Falcon telescopes on a set of nearby (< 25 pc) M dwarfs using infrared filters and a range of exposure times, as well as sample light curves created from images gathered during known transits of varying transit depths. An investigation of survey design parameters is also described, including an analysis of site-specific weather data, anticipated telescope time allocation and the percentage of nearby M dwarfs with sufficient check stars within the Falcons' 11' x 11' field-of-view required to perform effective differential photometry. The results of this ongoing effort will inform the likelihood of discovering one (or more) habitable-zone exoplanets given current occurrence rate estimates over a nominal five-year campaign, and will dictate specific survey design features in preparation for initiating project execution when the FTN begins full-scale automated operations.

  13. CELESTA: A Catalog of Earth-Like Exoplanet Survey Targets

    NASA Astrophysics Data System (ADS)

    Chandler, Colin Orion; McDonald, Iain; Kane, Stephen R.

    2016-01-01

    Locating planets in circumstellar Habitable Zones is a priority for many exoplanet surveys. Space-based and ground-based surveys alike require robust toolsets to aid in target selection and mission planning. We present the Catalog of Earth-Like Exoplanet Survey Targets (CELESTA), a database of Habitable Zones around 36,000 nearby stars. We calculated stellar parameters, including effective temperatures, masses, and radii, and we quantified the orbital distances and periods corresponding to the circumstellar Habitable Zones. We gauged the accuracy of our predictions by contrasting CELESTA's computed parameters to observational data. We ascertain a potential return on investment by computing the number of Habitable Zones probed for a given survey duration. A versatile framework for extending the functionality of CELESTA into the future enables ongoing comparisons to new observations, and recalculations when updates to Habitable Zone models, stellar temperatures, or parallax data become available. We expect to upgrade and expand CELESTA using data from the Gaia mission as the data becomes available.

  14. A 100-Night Exoplanet Imaging Survey at the LBT

    NASA Astrophysics Data System (ADS)

    Zimmerman, Neil; Skemer, Andrew; Apai, Daniel; Bailey, Vanessa; Biller, Beth; Bonnefoy, Mickael; Brandner, Wolfgang; Buenzli, Esther; Close, Laird; Crepp, Justin; Defrere, Denis; Desidera, Silvano; Eisner, Josh; Esposito, Simone; Fortney, Jonathan; Henning, Thomas; Hinz, Phil; Hofmann, Karl-Heinz; Leisenring, Jarron; Males, Jared; Millan-Gabet, Rafael; Morzinski, Katie; Pascucci, Ilaria; Patience, Jenny; Rieke, George; Schertl, Dieter; Schlieder, Joshua; Skrutskie, Michael; Su, Kate; Woodward, Chick; Weigelt, Gerd

    2013-07-01

    In February 2013, the LEECH (LBTI Exozodi Exoplanet Common Hunt) survey began its 100-night campaign from the Large Binocular Telescope atop Mount Graham in Arizona. LEECH neatly complements other high-contrast planet imaging efforts by observing stars in L' band (3.8 microns) as opposed to the shorter wavelength near-infrared bands (1-2.3 microns). This part of the spectrum offers deeper mass sensitivity for intermediate age (several hundred Myr-old) systems, since their Jovian-mass planets radiate predominantly in the mid-infrared. We present the science goals for LEECH and a preliminary contrast curve from some early data.

  15. LEECH: A 100 Night Exoplanet Imaging Survey at the LBT

    NASA Astrophysics Data System (ADS)

    Skemer, Andrew; Apai, Daniel; Bailey, Vanessa; Biller, Beth; Bonnefoy, Mickael; Brandner, Wolfgang; Buenzli, Esther; Close, Laird; Crepp, Justin; Defrere, Denis; Desidera, Silvano; Eisner, Josh; Esposito, Simone; Fortney, Jonathan; Henning, Thomas; Hinz, Phil; Hofmann, Karl-Heinz; Leisenring, Jarron; Males, Jared; Millan-Gabet, Rafael; Morzinski, Katie; Oza, Apurva; Pascucci, Ilaria; Patience, Jenny; Rieke, George; Schertl, Dieter; Schlieder, Joshua; Skrutskie, Mike; Su, Kate; Weigelt, Gerd; Woodward, Charles E.; Zimmerman, Neil

    2014-01-01

    In February 2013, the LEECH (LBTI Exozodi Exoplanet Common Hunt) survey began its 100-night campaign from the Large Binocular Telescope atop Mount Graham in Arizona. LEECH neatly complements other high-contrast planet imaging efforts by observing stars in L' band (3.8 microns) as opposed to the shorter wavelength near-infrared bands (1-2.3 microns). This part of the spectrum offers deeper mass sensitivity for intermediate age (several hundred Myr-old) systems, since their Jovian-mass planets radiate predominantly in the mid-infrared. In this proceedings, we present the science goals for LEECH and a preliminary contrast curve from some early data.

  16. Exploring the diversity of exoplanet atmospheres from the ground with the ACCESS Survey

    NASA Astrophysics Data System (ADS)

    Espinoza, Nestor; Jordan, Andres; Apai, Daniel; Lopez-Morales, Mercedes; Rackham, Benjamin; Lewis, Nikole K.; Fraine, Jonathan; Diaz-Pérez, Ryan; Rodler, Florian; Wells, Robert; Osip, David

    2015-12-01

    One of the most exciting possibilities enabled by transiting exoplanets is to measure their atmospheric properties through the technique of transmission spectroscopy: the variation of the transit depth as a function of wavelength due to starlight interacting with the atmosphere of the exoplanet. Motivated by the need of optical transmission spectra of exoplanets, we recently launched the Arizona-CfA-Católica Exoplanet Spectroscopy Survey (ACCESS), which aims at studying the atmospheres of ~20 exoplanets ranging from super-Earths to hot-Jupiters in the entire optical atmospheric window using ground-based facilities from both northern and southern hemispheres. In this talk, I will present the survey and its first results using Magellan/IMACS data, focusing on the lessons learned and future prospects of the survey.

  17. The Gemini Planet Imager Exoplanet Survey (GPIES) Campaign Initial Results

    NASA Astrophysics Data System (ADS)

    Patience, Jennifer; Macintosh, Bruce; Graham, James R.; Barman, Travis; De Rosa, Robert; Konopacky, Quinn; Marley, Mark; Marois, Christian; Nielsen, Eric Ludwig; Pueyo, Laurent; Rajan, Abhijith; Rameau, Julien; Saumon, Didier; Wang, Jason

    2015-12-01

    The Gemini Planet Imager (GPI) is a next-generation coronagraphic integral field unit with the sensitivity and resolution to detect planetary companions with separations of 0”.2 to 1”.0 around a large set of stars. An 890-hour GPI survey of 600 young, nearby stars commenced in late-2014, and approximately 100 stars have been observed thus far. The central aims of the program are: (1) the discovery of a population of giant planets with orbital radii of 5-50 AU comparable to Solar System gas giant orbits, (2) the characterization of the atmospheric properties of young planetary companions, and (3) the exploration of planet-disk interactions. Initial results from GPI exoplanet observations include the discovery of a new planetary companion to a young F-star; the planet spectrum shows a strong signature of methane absorption, indicating a cooler temperature than previously imaged young planets. An overview of the survey scope, current detection limits, and initial results will be presented.

  18. HST hot-Jupiter transmission spectral survey: from clear to cloudy exoplanets

    NASA Astrophysics Data System (ADS)

    Sing, David K.; Fortney, Jonathan J.; Nikolov, Nikolay; Wakeford, Hannah; Kataria, Tiffany; Evans, Tom M.; Aigrain, Suzanne; Ballester, Gilda E.; Burrows, Adam Seth; Deming, Drake; Desert, Jean-Michel; Gibson, Neale; Henry, Gregory W.; Huitson, Catherine; Knutson, Heather; Lecavelier des Etangs, Alain; Pont, Frederic; Showman, Adam P.; Vidal-Madjar, Alfred; Williamson, Michael W.; Wilson, Paul A.

    2016-01-01

    The large number of transiting exoplanets has prompted a new era of atmospheric studies, with comparative exoplanetology now possible. Here we present the comprehensive results from a Large program with the Hubble Space Telecope, which has recently obtained optical and near-IR transmission spectra for eight hot-Jupiter exoplanets in conjunction with warm Spitzer transit photometry. The spectra show a wide range of spectral behavior, which indicates diverse cloud and haze properties in their atmospheres. We will discuss the overall findings from the survey, comment on common trends observed in the exoplanet spectra, and remark on their theoretical implications.

  19. 20 Years of Exoplanets: From Surveys Towards Characterization

    NASA Astrophysics Data System (ADS)

    Rauscher, Emily

    2015-11-01

    Twenty years ago the discovery of the first planet outside of our solar system ushered in a new subfield of exoplanet study. In the years since, the number of known planets has skyrocketed into the thousands, due to an ever-expanding pool of detection methods, projects and missions, and substantial improvements in technique. These remarkable discoveries have revealed an exoplanet population that is highly diverse, in many cases breaking expectations set by the single example of our own solar system, and providing us with the opportunity to study planets under a wide range of physical conditions. Equally as exciting as the increasing number of known exoplanets, within the last dozen years we have seen the move from exoplanet discovery to characterization we are currently able to measure atmospheric properties of many of the brightest exoplanets. We are now in an era where we can study the diversity of atmospheric conditions for dozens of exoplanets, including measurements of their temperatures, albedos, compositions, and in some cases even more detailed information about their two- or three-dimensional atmospheric structures and circulation patterns. In this talk I will review the current state of theory and observations, the lessons we have learned, and the questions and techniques that direct future work.

  20. Tidal synchronization of close-in satellites and exoplanets: II. Spin dynamics and extension to Mercury and exoplanet host stars

    NASA Astrophysics Data System (ADS)

    Ferraz-Mello, Sylvio

    2015-08-01

    This paper deals with the application of the creep tide theory (Ferraz-Mello, Celest Mech Dyn Astron 116:109, 2013a) to the rotation of close-in satellites, Mercury, close-in exoplanets, and their host stars. The solutions show different behaviors with two extreme cases: close-in giant gaseous planets with fast relaxation (low viscosity) and satellites and Earth-like planets with slow relaxation (high viscosity). The rotation of close-in gaseous planets follows the classical Darwinian pattern: it is tidally driven toward a stationary solution that is synchronized with the orbital motion when the orbit is circular, but if the orbit is elliptical, it has a frequency larger than the orbital mean motion. The rotation of rocky bodies, however, may be driven to several attractors whose frequencies are times the mean motion. The number of attractors increases with the viscosity of the body and with the orbital eccentricity. The final stationary state depends on the initial conditions. The classical example is Mercury, whose rotational period is 2/3 of the orbital period (3/2 attractor). The planet behaves as a molten body with a relaxation that allowed it to cross the 2/1 attractor without being trapped but not to escape being trapped in the 3/2 one. In that case, the relaxation is estimated to lie in the interval (equivalent to a quality factor roughly constrained to the interval ). The stars have a relaxation similar to the hot Jupiters, and their rotation is also driven to the only stationary solution existing in these cases. However, solar-type stars may lose angular momentum due to stellar wind, braking the rotation and displacing the attractor toward larger periods. Old, active host stars with big close-in companions generally have rotational periods larger than the orbital periods of the companions. The paper also includes a study of energy dissipation and the evolution of orbital eccentricity.

  1. The LEECH Exoplanet Imaging Survey: Characterization of the Coldest Directly Imaged Exoplanet, GJ 504 b, and Evidence for Superstellar Metallicity

    NASA Astrophysics Data System (ADS)

    Skemer, Andrew J.; Morley, Caroline V.; Zimmerman, Neil T.; Skrutskie, Michael F.; Leisenring, Jarron; Buenzli, Esther; Bonnefoy, Mickael; Bailey, Vanessa; Hinz, Philip; Defrére, Denis; Esposito, Simone; Apai, Dániel; Biller, Beth; Brandner, Wolfgang; Close, Laird; Crepp, Justin R.; De Rosa, Robert J.; Desidera, Silvano; Eisner, Josh; Fortney, Jonathan; Freedman, Richard; Henning, Thomas; Hofmann, Karl-Heinz; Kopytova, Taisiya; Lupu, Roxana; Maire, Anne-Lise; Males, Jared R.; Marley, Mark; Morzinski, Katie; Oza, Apurva; Patience, Jenny; Rajan, Abhijith; Rieke, George; Schertl, Dieter; Schlieder, Joshua; Stone, Jordan; Su, Kate; Vaz, Amali; Visscher, Channon; Ward-Duong, Kimberly; Weigelt, Gerd; Woodward, Charles E.

    2016-02-01

    As gas giant planets and brown dwarfs radiate away the residual heat from their formation, they cool through a spectral type transition from L to T, which encompasses the dissipation of cloud opacity and the appearance of strong methane absorption. While there are hundreds of known T-type brown dwarfs, the first generation of directly imaged exoplanets were all L type. Recently, Kuzuhara et al. announced the discovery of GJ 504 b, the first T dwarf exoplanet. GJ 504 b provides a unique opportunity to study the atmosphere of a new type of exoplanet with a ˜500 K temperature that bridges the gap between the first directly imaged planets (˜1000 K) and our own solar system's Jupiter (˜130 K). We observed GJ 504 b in three narrow L-band filters (3.71, 3.88, and 4.00 μm), spanning the red end of the broad methane fundamental absorption feature (3.3 μm) as part of the LBTI Exozodi Exoplanet Common Hunt (LEECH) exoplanet imaging survey. By comparing our new photometry and literature photometry with a grid of custom model atmospheres, we were able to fit GJ 504 b's unusual spectral energy distribution for the first time. We find that GJ 504 b is well fit by models with the following parameters: Teff = 544 ± 10 K, g < 600 m s-2, [M/H] = 0.60 ± 0.12, cloud opacity parameter of fsed = 2-5, R = 0.96 ± 0.07 RJup, and log(L) = -6.13 ± 0.03 L⊙, implying a hot start mass of 3-30 Mjup for a conservative age range of 0.1-6.5 Gyr. Of particular interest, our model fits suggest that GJ 504 b has a superstellar metallicity. Since planet formation can create objects with nonstellar metallicities, while binary star formation cannot, this result suggests that GJ 504 b formed like a planet, not like a binary companion. The LBT is an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrophisica, Italy; LBT

  2. ARIEL: Atmospheric Remote-Sensing Infrared Exoplanet Large-survey

    NASA Astrophysics Data System (ADS)

    Tinetti, Giovanna

    2015-11-01

    More than 1,000 extrasolar systems have been discovered, hosting nearly 2,000 exoplanets. Ongoing and planned ESA and NASA missions from space such as GAIA, Cheops, PLATO, K2 and TESS will increase the number of known systems to tens of thousands.Of all these exoplanets we know very little, i.e. their orbital data and, for some of these, their physical parameters such as their size and mass. In the past decade, pioneering results have been obtained using transit spectroscopy with Hubble, Spitzer and ground-based facilities, enabling the detection of a few of the most abundant ionic, atomic and molecular species and to constrain the planet’s thermal structure. Future general purpose facilities with large collecting areas will allow the acquisition of better exoplanet spectra, compared to the currently available, especially from fainter targets. A few tens of planets will be observed with JWST and E-ELT in great detail.A breakthrough in our understanding of planet formation and evolution mechanisms will only happen through the observation of the planetary bulk and atmospheric composition of a statistically large sample of planets. This requires conducting spectroscopic observations covering simultaneously a broad spectral region from the visible to the mid-IR. It also requires a dedicated space mission with the necessary photometric stability to perform these challenging measurements and sufficient agility to observe multiple times ~500 exoplanets over mission life-time.The ESA-M4 mission candidate ARIEL is designed to accomplish this goal and will provide a complete, statistically significant sample of gas-giants, Neptunes and super-Earths with temperatures hotter than 600K, as these types of planets will allow direct observation of their bulk properties, enabling us to constrain models of planet formation and evolution.The ARIEL consortium currently includes academic institutes and industry from eleven countries in Europe; the consortium is open and invites new

  3. Survey: National Environmental Satellite Service

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The national Environmental Satellite Service (NESS) receives data at periodic intervals from satellites of the Synchronous Meteorological Satellite/Geostationary Operational Environmental Satellite series and from the Improved TIROS (Television Infrared Observational Satellite) Operational Satellite. Within the conterminous United States, direct readout and processed products are distributed to users over facsimile networks from a central processing and data distribution facility. In addition, the NESS Satellite Field Stations analyze, interpret, and distribute processed geostationary satellite products to regional weather service activities.

  4. Synthesizing exoplanet demographics from radial velocity and microlensing surveys. I. Methodology

    SciTech Connect

    Clanton, Christian; Gaudi, B. Scott

    2014-08-20

    Motivated by the order of magnitude difference in the frequency of giant planets orbiting M dwarfs inferred by microlensing and radial velocity (RV) surveys, we present a method for comparing the statistical constraints on exoplanet demographics inferred from these methods. We first derive the mapping from the observable parameters of a microlensing-detected planet to those of an analogous planet orbiting an RV-monitored star. Using this mapping, we predict the distribution of RV observables for the planet population inferred from microlensing surveys, taking care to adopt reasonable priors for, and properly marginalize over, the unknown physical parameters of microlensing-detected systems. Finally, we use simple estimates of the detection limits for a fiducial RV survey to predict the number and properties of analogs of the microlensing planet population such an RV survey should detect. We find that RV and microlensing surveys have some overlap, specifically for super-Jupiter mass planets (m{sub p} ≳ 1 M {sub Jup}) with periods between ∼3-10 yr. However, the steeply falling planetary mass function inferred from microlensing implies that, in this region of overlap, RV surveys should infer a much smaller frequency than the overall giant planet frequency (m{sub p} ≳ 0.1 M {sub Jup}) inferred by microlensing. Our analysis demonstrates that it is possible to statistically compare and synthesize data sets from multiple exoplanet detection techniques in order to infer exoplanet demographics over wider regions of parameter space than are accessible to individual methods. In a companion paper, we apply our methodology to several representative microlensing and RV surveys to derive the frequency of planets around M dwarfs with orbits of ≲ 30 yr.

  5. Exoplanets -New Results from Space and Ground-based Surveys

    NASA Astrophysics Data System (ADS)

    Udry, Stephane

    The exploration of the outer solar system and in particular of the giant planets and their environments is an on-going process with the Cassini spacecraft currently around Saturn, the Juno mission to Jupiter preparing to depart and two large future space missions planned to launch in the 2020-2025 time frame for the Jupiter system and its satellites (Europa and Ganymede) on the one hand, and the Saturnian system and Titan on the other hand [1,2]. Titan, Saturn's largest satellite, is the only other object in our Solar system to possess an extensive nitrogen atmosphere, host to an active organic chemistry, based on the interaction of N2 with methane (CH4). Following the Voyager flyby in 1980, Titan has been intensely studied from the ground-based large telescopes (such as the Keck or the VLT) and by artificial satellites (such as the Infrared Space Observatory and the Hubble Space Telescope) for the past three decades. Prior to Cassini-Huygens, Titan's atmospheric composition was thus known to us from the Voyager missions and also through the explorations by the ISO. Our perception of Titan had thus greatly been enhanced accordingly, but many questions remained as to the nature of the haze surrounding the satellite and the composition of the surface. The recent revelations by the Cassini-Huygens mission have managed to surprise us with many discoveries [3-8] and have yet to reveal more of the interesting aspects of the satellite. The Cassini-Huygens mission to the Saturnian system has been an extraordinary success for the planetary community since the Saturn-Orbit-Insertion (SOI) in July 2004 and again the very successful probe descent and landing of Huygens on January 14, 2005. One of its main targets was Titan. Titan was revealed to be a complex world more like the Earth than any other: it has a dense mostly nitrogen atmosphere and active climate and meteorological cycles where the working fluid, methane, behaves under Titan conditions the way that water does on

  6. IMAGES: An IMage Archive Generated for Exoplanet Surveys

    NASA Astrophysics Data System (ADS)

    Tanner, A.

    2014-03-01

    Over the past few years the advent of adaptive optics and central star suppression has resulted in multiple low-mass companion surveys of both main sequence and young star systems. The goal of these surveys is to directly detect sub-stellar companions such as brown dwarfs (<75 MJ), very low mass brown dwarfs (20-10 MJ) and massive giant planets (<13 MJ) at separations of >10 AU from their host stars. To date, direct imaging studies have produced a sample of directly imaged, very low mass objects (3-22 MJ, Schneider 2013). This small sample of very low-mass companions results from observations of over one thousand mature and young stars. Since many AO observing programs are quick to publish interesting common proper motion companions but slow to publish the results of the entire survey, there is a surplus of unpublished images that can be utilized for both future high contrast imaging programs and, when combined into a ~3000 star survey, provide further constraints on the companion fraction as a function of age, spectral type, and planet formation environment. Therefore, it is the goal of the IMAGES program to complete a high contrast imaging archive. Our database will help scientists use their telescope time more efficiently and would increase the discovery rate. This archive will also serve as a testbed for the development of a user-friendly, user contributor archive in which astronomers can upload new archival high contrast images in addition to downloading.

  7. ARIEL - The Atmospheric Remote-sensing Infrared Exoplanet Large-survey

    NASA Astrophysics Data System (ADS)

    Eccleston, P.; Tinetti, G.

    2015-10-01

    More than 1,000 extrasolar systems have been discovered, hosting nearly 2,000 exoplanets. Ongoing and planned ESA and NASA missions from space such as GAIA, Cheops, PLATO, K2 and TESS, plus ground based surveys, will increase the number of known systems to tens of thousands. Of all these exoplanets we know very little; i.e. their orbital data and, for some of these, their physical parameters such as their size and mass. In the past decade, pioneering results have been obtained using transit spectroscopy with Hubble, Spitzer and ground-based facilities, enabling the detection of a few of the most abundant ionic, atomic and molecular species and to constrain the planet's thermal structure. Future general purpose facilities with large collecting areas will allow the acquisition of better exoplanet spectra, compared to the currently available, especially from fainter targets. A few tens of planets will be observed with JWST and E-ELT in great detail. A breakthrough in our understanding of planet formation and evolution mechanisms will only happen through the observation of the planetary bulk and atmospheric composition of a statistically large sample of planets. This requires conducting spectroscopic observations covering simultaneously a broad spectral region from the visible to the mid-IR. It also requires a dedicated space mission with the necessary photometric stability to perform these challenging measurements and sufficient agility to observe multiple times ~500 exoplanets over 3.5 years. The ESA Cosmic Vision M4 mission candidate ARIEL is designed to accomplish this goal and will provide a complete, statistically significant sample of gas-giants, Neptunes and super-Earths with temperatures hotter than 600K, as these types of planets will allow direct observation of their bulk properties, enabling us to constrain models of planet formation and evolution. The ARIEL consortium currently includes academic institutes and industry from eleven countries in Europe; the

  8. Teaching practical leadership in MIT satellite development class: CASTOR and Exoplanet projects

    NASA Astrophysics Data System (ADS)

    Babuscia, Alessandra; Craig, Jennifer L.; Connor, Jane A.

    2012-08-01

    For more than a decade, the Aeronautics and Astronautics Department at MIT has offered undergraduate students the opportunity of conceiving, developing, implementing and operating new spacecraft's missions. During a three term class, junior and senior students experience all the challenges of a true engineering team project: design, analysis, testing, technical documentation development, team management, and leadership. Leadership instruction is an important part of the curricula; through the development of leadership skills, students learn to manage themselves and each other in a more effective way, increasing the overall productivity of the team. Also, a strong leadership education is a key factor in improving the abilities of future engineers to be effective team members and leaders in the companies and agencies in which they will work. However, too often leadership instruction is presented in an abstract way, which does not provide students with suggestions for immediate applicability. As a consequence, students underestimate the potential that leadership education can have on the development of their projects. To counteract that effect, a new approach for teaching "practical" leadership has been developed. This approach is composed of a set of activities developed to improve students' leadership skills in the context of a project. Specifically, this approach has been implemented in the MIT satellite development class. In that class, students experienced the challenges of building two satellites: CASTOR and Exoplanet. These two missions are real space projects which will be launched in the next two years, and which involve cooperation with different entities (MIT, NASA, and Draper). Hence, the MIT faculty was interested in developing leadership activities to improve the productivity of the teams in a short time. In fact, one of the key aspects of the approach proposed is that it can be quickly implemented in a single semester, requiring no more than 4 h of

  9. Subaru Direct Imaging Survey of Wide-Orbit Exoplanets and Solar-System-Scale Disks

    NASA Astrophysics Data System (ADS)

    Tamura, Motohide

    2015-08-01

    SEEDS (Strategic Explorations of Exoplanets and Disks with Subaru) is the first Subaru Strategic Program, whose aim is to conduct a direct imaging survey for giant planets as well as protoplanetary/debris disks at a few to a few tens of AU region around 500 nearby solar-type or more massive young stars devoting 120 Subaru nights for 5 years from 2009. The targets are composed of five categories spanning the ages of ~1 Myr to ~1 Gyr. Some RV-planet targets with older ages are also observed. We describe this survey and present its main results. The topics include (1) statistic of wide-orbit planets, (2) detection and characterization of one of the most lowest-mass planet via direct imaging. (3) detection of a super-Jupiter around the most massive star ever imaged, (4) detection of companions around retrograde exoplanet, (5) the discovery of unprecedentedly detailed structures of more than a dozen of protoplanetary disks and some debris disks. The detected structures such as wide gaps and spirals arms of a Solar-system scale could be signpost of planet.

  10. BASS-Ultracool : A Survey for Isolated Analogs of Methane Exoplanets

    NASA Astrophysics Data System (ADS)

    Gagné, Jonathan; Faherty, Jacqueline K.; Malo, Lison; Filippazzo, Joseph C.; Burgasser, Adam J.; Artigau, Etienne; Lafrenière, David; Doyon, Rene; Bowsher, Emily; Nicholls, Christine P.

    2015-12-01

    I will present BASS-Ultracool, a new survey to identify isolated cold, late L and T-type members of young moving groups. These objects have masses below 10 MJup and physical properties similar to those of exoplanets identified with the direct-imaging method. The discovery of such isolated planetary-mass objects will allow us to characterize their atmospheres with unprecedented signal-to-noise and spectroscopic resolution due to the absence of a host star. They will serve as benchmarks to understand cold exoplanets such as the recently discovered 51 Eri b.I will also present how the prototype version of the BASS-Ultracool survey has already identified the first isolated T-type member of a nearby moving group SDSS J1110+0116, which is a young 10-12 MJup T5.5 member of the ~150 Myr-old AB Doradus moving group. This object is an isolated and slightly cooler version of the previously identified T3.5 AB Doradus member GU Psc b.

  11. EXOPLANETS FROM THE ARCTIC: THE FIRST WIDE-FIELD SURVEY AT 80 Degree-Sign N

    SciTech Connect

    Law, Nicholas M.; Sivanandam, Suresh; Carlberg, Raymond; Salbi, Pegah; Ngan, Wai-Hin Wayne; Kerzendorf, Wolfgang; Ahmadi, Aida; Steinbring, Eric; Murowinski, Richard

    2013-03-15

    Located within 10 Degree-Sign of the North Pole, northern Ellesmere Island offers continuous darkness in the winter months. This capability can greatly enhance the detection efficiency of planetary transit surveys and other time domain astronomy programs. We deployed two wide-field cameras at 80 Degree-Sign N, near Eureka, Nunavut, for a 152 hr observing campaign in 2012 February. The 16 megapixel camera systems were based on commercial f/1.2 lenses with 70 mm and 42 mm apertures, and they continuously imaged 504 and 1295 deg{sup 2}, respectively. In total, the cameras took over 44,000 images and produced better than 1% precision light curves for approximately 10,000 stars. We describe a new high-speed astrometric and photometric data reduction pipeline designed for the systems, test several methods for the precision flat fielding of images from very-wide-angle cameras, and evaluate the cameras' image qualities. We achieved a scintillation-limited photometric precision of 1%-2% in each 10 s exposure. Binning the short exposures into 10 minute chunks provided a photometric stability of 2-3 mmag, sufficient for the detection of transiting exoplanets around the bright stars targeted by our survey. We estimate that the cameras, when operated over the full Arctic winter, will be capable of discovering several transiting exoplanets around bright (m{sub V} < 9.5) stars.

  12. A Large Hubble Space Telescope Survey of Low-Mass Exoplanets

    NASA Astrophysics Data System (ADS)

    Benneke, Björn; Crossfield, Ian; Knutson, Heather; Lothringer, Joshua; Dragomir, Diana; Fortney, Jonathan J.; Howard, Andrew; McCullough, Peter R.; Kempton, Eliza; Morley, Caroline

    2016-06-01

    The discovery of short-period planets with masses and radii between Earth and Neptune was one of the biggest surprises in the brief history of exoplanet science. From the Kepler mission, we now know that these “super-Earths” or "sub-Neptunes" orbit at least 40% of stars, likely representing the most common outcome of planet formation. Despite this ubiquity, we know little about their typical compositions and formation histories. Spectroscopic transit observations combined with powerful atmospheric retrieval tools can shed new light on these mysterious worlds. In this talk, we will present the main results from our 124-orbit Hubble Space Telescope survey to reveal the chemical diversity and formation histories of super-Earths. This unprecedented HST survey provides the first comprehensive look at this intriguing new class of planets ranging from 1 Neptune mass and temperatures close to 2000K to a 1 Earth mass planet near the habitable zone of its host star.

  13. RR Lyrae Stars in the GCVS Observed by the Qatar Exoplanet Survey

    NASA Astrophysics Data System (ADS)

    Bramich, D. M.; Alsubai, K. A.; Arellano Ferro, A.; Parley, N. R.; Collier Cameron, A.; Horne, K.; Pollacco, D.; West, R. G.

    2014-05-01

    We used the light curve archive of the Qatar Exoplanet Survey to investigate the RR Lyrae variable stars listed in the GCVS. Of 588 variables studied, we reclassified 14 as eclipsing binaries, one as an RS CVn type variable, one as an irregular variable, four as classical Cepheids, and one as a type II Cepheid, while also improving their periods. We also report new RR Lyrae sub-type classifications for 65 variables and improve on the GCVS period estimates for 135 RR Lyrae variables. There are seven double-mode RR Lyrae stars in the sample for which we measured their fundamental and first overtone periods. Finally, we detected the Blazhko effect in 38 of the RR Lyrae stars for the first time and we successfully measured the Blazhko period for 26 of them.

  14. Use of APT satellite infrared data in oceanographic survey operations

    NASA Technical Reports Server (NTRS)

    Laviolette, P. E.; Stuart, L., Jr.; Vermillion, C.

    1975-01-01

    Experiments are described which were conducted to explore and develop the application of satellite infrared data to oceanographic post survey data analysis. The use of satellite infrared and visible radiation data in oceanographic surveys is examined.

  15. High contrast imaging at the LBT: the LEECH exoplanet imaging survey

    NASA Astrophysics Data System (ADS)

    Skemer, Andrew J.; Hinz, Philip; Esposito, Simone; Skrutskie, Michael F.; Defrère, Denis; Bailey, Vanessa; Leisenring, Jarron; Apai, Daniel; Biller, Beth; Bonnefoy, Mickaël.; Brandner, Wolfgang; Buenzli, Esther; Close, Laird; Crepp, Justin; De Rosa, Robert J.; Desidera, Silvano; Eisner, Josh; Fortney, Jonathan; Henning, Thomas; Hofmann, Karl-Heinz; Kopytova, Taisiya; Maire, Anne-Lise; Males, Jared R.; Millan-Gabet, Rafael; Morzinski, Katie; Oza, Apurva; Patience, Jenny; Rajan, Abhijith; Rieke, George; Schertl, Dieter; Schlieder, Joshua; Su, Kate; Vaz, Amali; Ward-Duong, Kimberly; Weigelt, Gerd; Woodward, Charles E.; Zimmerman, Neil

    2014-07-01

    In Spring 2013, the LEECH (LBTI Exozodi Exoplanet Common Hunt) survey began its ~130-night campaign from the Large Binocular Telescope (LBT) atop Mt Graham, Arizona. This survey benefits from the many technological achievements of the LBT, including two 8.4-meter mirrors on a single fixed mount, dual adaptive secondary mirrors for high Strehl performance, and a cold beam combiner to dramatically reduce the telescope's overall background emissivity. LEECH neatly complements other high-contrast planet imaging efforts by observing stars at L' (3.8 μm), as opposed to the shorter wavelength near-infrared bands (1-2.4 μm) of other surveys. This portion of the spectrum offers deep mass sensitivity, especially around nearby adolescent (~0.1-1 Gyr) stars. LEECH's contrast is competitive with other extreme adaptive optics systems, while providing an alternative survey strategy. Additionally, LEECH is characterizing known exoplanetary systems with observations from 3-5μm in preparation for JWST.

  16. The LEECH Exoplanet Imaging Survey. Further constraints on the planet architecture of the HR 8799 system

    NASA Astrophysics Data System (ADS)

    Maire, A.-L.; Skemer, A. J.; Hinz, P. M.; Desidera, S.; Esposito, S.; Gratton, R.; Marzari, F.; Skrutskie, M. F.; Biller, B. A.; Defrère, D.; Bailey, V. P.; Leisenring, J. M.; Apai, D.; Bonnefoy, M.; Brandner, W.; Buenzli, E.; Claudi, R. U.; Close, L. M.; Crepp, J. R.; De Rosa, R. J.; Eisner, J. A.; Fortney, J. J.; Henning, T.; Hofmann, K.-H.; Kopytova, T. G.; Males, J. R.; Mesa, D.; Morzinski, K. M.; Oza, A.; Patience, J.; Pinna, E.; Rajan, A.; Schertl, D.; Schlieder, J. E.; Su, K. Y. L.; Vaz, A.; Ward-Duong, K.; Weigelt, G.; Woodward, C. E.

    2015-04-01

    Context. Astrometric monitoring of directly imaged exoplanets allows the study of their orbital parameters and system architectures. Because most directly imaged planets have long orbital periods (>20 AU), accurate astrometry is challenging when based on data acquired on timescales of a few years and usually with different instruments. The LMIRCam camera on the Large Binocular Telescope is being used for the LBT Exozodi Exoplanet Common Hunt (LEECH) survey to search for and characterize young and adolescent exoplanets in L' band (3.8 μm), including their system architectures. Aims: We first aim to provide a good astrometric calibration of LMIRCam. Then, we derive new astrometry, test the predictions of the orbital model of 8:4:2:1 mean motion resonance proposed for the system, and perform new orbital fitting of the HR 8799 bcde planets. We also present deep limits on a putative fifth planet inside the known planets. Methods: We use observations of HR 8799 and the Θ1 Ori C field obtained during the same run in October 2013. Results: We first characterize the distortion of LMIRCam. We determine a platescale and a true north orientation for the images of 10.707 ± 0.012 mas/pix and -0.430 ± 0.076°, respectively. The errors on the platescale and true north orientation translate into astrometric accuracies at a separation of 1'' of 1.1 mas and 1.3 mas, respectively. The measurements for all planets agree within 3σ with a predicted ephemeris. The orbital fitting based on the new astrometric measurements favors an architecture for the planetary system based on 8:4:2:1 mean motion resonance. The detection limits allow us to exclude a fifth planet slightly brighter or more massive than HR 8799 b at the location of the 2:1 resonance with HR 8799 e (~9.5 AU) and about twice as bright as HR 8799 cde at the location of the 3:1 resonance with HR 8799 e (~7.5 AU). The LBT is an international collaboration among institutions in the United States, Italy, and Germany. LBT

  17. Surveying Nearby M dwarfs with Gaia: A Treasure Trove for Exoplanet Astrophysics

    NASA Astrophysics Data System (ADS)

    Sozzetti, A.; Tinetti, G.; Lattanzi, M. G.; Micela, G.; Morbidelli, R.; Giacobbe, P.

    2011-10-01

    Cool, nearby M dwarfs within a few tens of parsecs from the Sun are today becoming the focus of dedicated experiments in the realm of exoplanets astrophysics. This is due to the shift in theoretical paradigms in light of new observations, and thanks to the improved understanding of the observational opportunities for planet detection and characterization provided by this sample. Gaia, in its all-sky survey, will deliver precision astrometry for a magnitude-limited (V=20) sample of M dwarfs in the vicinity of the Sun, providing an inventory of cool nearby stars with a much higher degree of completeness (particularly for late sub-types) with respect to currently available catalogs. We gauge the Gaia potential for precision astrometry of exoplanets orbiting a sample of actual M stars within 30 pc from the Sun. The stellar reservoir is carefully selected based on cross-correlation among catalogs in the literature (e.g., Lepine, PMSU).We express Gaia sensitivity thresholds as a function of system parameters and in view of the latest mission profile, including the most up-to-date astrometric error model. The simulations also provide insight on the capability of high-precision astrometry to reconstruct the underlying orbital elements and mass distributions of the generated companions. We investigate the synergy between the Gaia data on nearby M dwarfs and other ground-based and spaceborne programs for planet detection and characterization, with a particular focus on: a) the improvements in the determination of transiting planet parameters thanks to the exquisitely precise stellar distances determined by Gaia; b) the betterment in orbit modeling when Gaia astrometry and precision radial-velocities are available for the same targets; and c) the ability of Gaia to carefully predict the ephemerides of detected (transiting and non-transiting) planets aroundM stars, for the purpose of spectroscopic characterization of their atmospheres with dedicated observatories in space

  18. The Gaia Astrometric Survey of Nearby M Dwarfs: A Treasure Trove for Exoplanet Astrophysics

    NASA Astrophysics Data System (ADS)

    Sozzetti, Alessandro; Giacobbe, P.; Lattanzi, M. G.; Micela, G.; Tinetti, G.

    2011-09-01

    Cool, nearby M dwarfs within a few tens of parsecs from the Sun are becoming the focus of dedicated experiments in the realm of exoplanets astrophysics. This is due to the shift in theoretical paradigms in light of new observations, and to the improved understanding of the observational opportunities for planet detection and characterization provided by this sample. Gaia, in its all-sky survey, will deliver precision astrometry for a magnitude-limited (V=20) sample of M dwarfs, providing an inventory of cool nearby stars with a much higher degree of completeness (particularly for late sub-types) with respect to currently available catalogs. We gauge the Gaia potential for precision astrometry of exoplanets orbiting a sample of already known dM stars within 30 pc from the Sun, carefully selected based on cross-correlation among catalogs in the literature (e.g., Lepine, PMSU). We express Gaia sensitivity thresholds as a function of system parameters and in view of the latest mission profile, including the most up-to-date astrometric error model. The simulations also provide insight on the capability of high-precision astrometry to reconstruct the underlying orbital elements and mass distributions of the generated companions. These results will help in evaluating the complete expected Gaia planet population around late-type stars. We investigate the synergy between the Gaia data on nearby M dwarfs and other ground-based and space-borne programs for planet detection and characterization, with a particular focus on: a) the improvements in the determination of transiting planet parameters thanks to the exquisitely precise stellar distances determined by Gaia; b) the betterment in orbit modeling when Gaia astrometry and precision radial-velocities are available for the same targets; and c) the ability of Gaia to carefully predict the ephemerides of (transiting and non-transiting) planets around M stars, for spectroscopic characterization of their atmospheres with

  19. Thermodynamic Equations of State for Aqueous Solutions Applied to Deep Icy Satellite and Exoplanet Oceans

    NASA Astrophysics Data System (ADS)

    Vance, S.; Brown, J. M.; Bollengier, O.; Journaux, B.; Sotin, C.; Choukroun, M.; Barnes, R.

    2014-12-01

    Supporting life in icy world or exoplanet oceans may require global seafloor chemical reactions between water and rock. Such interactions have been regarded as limited in larger icy worlds such as Ganymede and Titan, where ocean depths approach 800 km and GPa pressures (>10katm). If the oceans are composed of pure water, such conditions are consistent with the presence of dense ice phases V and VI that cover the rocky seafloor. Exoplanets with oceans can obtain pressures sufficient to generate ices VII and VIII. We have previously demonstrated temperature gradients in such oceans on the order of 20 K or more, resulting from fluid compressibility in a deep adiabatic ocean based on our experimental work. Accounting for increases in density for highly saline oceans leads to the possibility of oceans perched under and between high pressure ices. Ammonia has the opposite effect, instead decreasing ocean density, as reported by others and confirmed by our laboratory measurements in the ammonia water system. Here we report on the completed equation of state for aqueous ammonia derived from our prior measurements and optimized global b-spline fitting methods We use recent diamond anvil cell measurements for water and ammonia to extend the equation of state to 400°C and beyond 2 GPa, temperatures and pressures applicable to icy worlds and exoplanets. Densities show much less temperature dependence but comparabe high-pressure derivatives to previously published ammonia-water properties derived for application to Titan (Croft et al. 1988). Thermal expansion is in better agreement with the more self-consistent equation of state of Tillner-Roth and Friend (1998). We also describe development of a planetary NaCl equation of state using recent measurements of phase boundaries and sound speeds. We examine implications of realistic ocean-ice thermodynamics for Titan and exoplanet interiors using the methodology recently applied to Ganymede for oceans dominated by MgSO4. High

  20. SERIES - Satellite Emission Range Inferred Earth Surveying

    NASA Technical Reports Server (NTRS)

    Macdoran, P. F.; Spitzmesser, D. J.; Buennagel, L. A.

    1983-01-01

    The Satellite Emission Range Inferred Earth Surveying (SERIES) concept is based on the utilization of NAVSTAR Global Positioning System (GPS) radio transmissions without any satellite modifications and in a totally passive mode. The SERIES stations are equipped with lightweight 1.5 m diameter dish antennas mounted on trailers. A series baseline measurement accuracy demonstration is considered, taking into account a 100 meter baseline estimation from approximately one hour of differential Doppler data. It is planned to conduct the next phase of experiments on a 150 m baseline. Attention is given to details regarding future baseline measurement accuracy demonstrations, aspects of ionospheric calibration in connection with subdecimeter baseline accuracy requirements of geodesy, and advantages related to the use of the differential Doppler or pseudoranging mode.

  1. VizieR Online Data Catalog: Catalog of Earth-Like Exoplanet Survey Targets (Chandler+, 2016)

    NASA Astrophysics Data System (ADS)

    Chandler, C. O.; McDonald, I.; Kane, S. R.

    2016-07-01

    We present the Catalog of Earth-Like Exoplanet Survey Targets (CELESTA), a database of habitable zones around 37000 nearby stars. The first step in creating CELESTA was assembling the input data. The Revised Hipparcos Catalog (van Leeuwen 2007, Cat. I/311) is a stellar catalog based on the original Hipparcos mission (Perryman et al. 1997, Cat. I/239) data set. Hipparcos, launched in 1989, recorded with great precision the parallax of nearby stars, ultimately leading to a database of 118218 stars. McDonald et al. 2012 (cat. J/MNRAS/427/343) calculated effective temperatures and luminosities for the Hipparcos stars. The next step was selecting appropriate stars for the construction of CELESTA. The Stellar Parameter Catalog of 103663 stars included many stars that were not suitable for our purposes, especially stars off the Main-Sequence (MS) branch, e.g., giants. Please refer to Section 3.2 in the paper for additional details about the star selection. The final CELESTA catalog contains 37354 stars (see Table2), each with a set of associated attributes, e.g., estimated mass, measured distance. The complete database can also be found online at a dedicated host (http://www.celesta.info/). (2 data files).

  2. The MUSCLES Treasury Survey: Temporally- and Spectrally-Resolved Irradiance from Low-mass Exoplanet Host Stars

    NASA Astrophysics Data System (ADS)

    France, Kevin; Parke Loyd, R. O.; Youngblood, Allison; Linsky, Jeffrey; MUSCLES Treasury Survey Team

    2016-01-01

    The spectral and temporal behavior of exoplanet host stars is a critical input to models of the chemistry and evolution of planetary atmospheres. High-energy photons (X-ray to near-UV; 5 - 3200 Ang) from these stars regulate the atmospheric temperature profiles and photochemistry on orbiting planets, influencing the production of potential "biomarker" gases. It has been shown that the atmospheric signatures of potentially habitable planets around low-mass stars may be significantly different from planets orbiting Sun-like stars owing to the different UV spectral energy distribution. I will present results from a panchromatic survey (Hubble/Chandra/XMM/optical) of M and K dwarf exoplanet hosts, the MUSCLES Treasury Survey (Measurements of the Ultraviolet Spectral Characteristics of Low-mass Exoplanetary Systems). We reconstruct the Lyman-alpha and extreme-UV (100-900 Ang) radiation lost to interstellar attenuation and create 5 Angstrom to 5 micron stellar irradiance spectra; these data will be publically available as a High-Level Science Product on MAST. We find that all low-mass exoplanet host stars exhibit significant chromospheric/transition region/coronal emission -- no "UV inactive" M dwarfs are observed. The F(far-UV)/F(near-UV) flux ratio, a driver for possible abiotic production of the suggested biomarkers O2 and O3, increases by ~3 orders of magnitude as the habitable zone moves inward from 1 to 0.1 AU, while the incident far-UV (912 - 1700 Ang) and XUV (5 - 900 Ang) radiation field strengths decrease by factors of a few across this range. Far-UV flare activity is common in 'optically inactive' M dwarfs; statistics from the entire sample indicate that large UV flares (E(300 - 1700 Ang) >= 10^31 erg) occur several times per day on typical M dwarf exoplanet hosts.

  3. Synthesizing Exoplanet Demographics

    NASA Astrophysics Data System (ADS)

    Clanton, Christian

    2016-01-01

    The discovery of thousands of exoplanets has revealed a large diversity of systems, the majority of which look nothing like our own. On the theoretical side, we are able to make ab initio calculations that make predictions about the properties of exoplanets. However, in order to link these predictions with observations, we must construct a statistical census of exoplanet demographics over as broad a range of parameters as possible. Current constraints on exoplanet demographics are typically constructed using the results of individual surveys using a single detection technique, and thus are incomplete. The only way to derive a statistically-complete census that samples a wide region of exoplanet parameter space is to synthesize the results from surveys employing all of the different discovery methods at our disposal. I present the first studies to demonstrate that this is actually possible, and describe a (mostly) de-biased exoplanet census that is constructed from the synthesis of results from microlensing, radial velocity, and direct imaging surveys. I will also discuss future work that will include the results of transit surveys (in particular, Kepler discoveries) to complete the census of exoplanets in our Galaxy, and describe the application of this census to develop the most comprehensive, observationally-constrained models of planet formation and evolution that have been derived to date.

  4. The MEarth project: an all-sky survey for transiting Earth-like exoplanets orbiting nearby M-dwarfs

    NASA Astrophysics Data System (ADS)

    Irwin, Jonathan; Berta-Thompson, Zachory K.; Charbonneau, David; Dittmann, Jason; Newton, Elisabeth R.

    2015-01-01

    The MEarth project is an operational all-sky survey searching for transiting Earth-like exoplanets around 3,000 of the closest mid-to-late M-dwarfs. These will be among the best planets in their size class for atmospheric characterization using present day and near-future instruments such as HST, JWST and ground-based Extremely Large Telescopes (ELTs), by virtue of the large observational signal sizes afforded by their small and bright host stars. We present an update on the status and recent scientific results of the survey from our two observing stations: MEarth-North at Fred Lawrence Whipple Observatory, Mount Hopkins, Arizona, and MEarth-South at Cerro Tololo Inter-American Observatory, Chile. MEarth-North discovered the transiting mini-Neptune exoplanet GJ 1214b, which currently has the best-studied atmosphere of any exoplanet in its size class. In addition to searching for planets, we actively pursue stellar astrophysics topics and characterization of the target star sample using MEarth data and supplementary spectroscopic follow-up. This has included measuring astrometric parallaxes for more than 1500 nearby stars, the discovery of 6 new low-mass eclipsing binaries amenable to direct measurement of the masses and radii of their components, and rotation periods, spectral classifications, metallicities and activity indices for hundreds of stars. The MEarth light curves themselves also provide a detailed record of the photometric behavior of the target stars, which include the most favorable and interesting targets to search for small and potentially habitable planets. This will be a valuable resource for all future surveys searching for planets around these stars. All light curves gathered during the survey are made publicly available after one year.The MEarth project gratefully acknowledges funding from the David and Lucile Packard Fellowship for Science and Engineering, the National Science Foundation under grants AST-0807690, AST-1109468, and AST-1004488

  5. Robo-AO Kepler Planetary Candidate Survey. II. Adaptive Optics Imaging of 969 Kepler Exoplanet Candidate Host Stars

    NASA Astrophysics Data System (ADS)

    Baranec, Christoph; Ziegler, Carl; Law, Nicholas M.; Morton, Tim; Riddle, Reed; Atkinson, Dani; Schonhut, Jessica; Crepp, Justin

    2016-07-01

    We initiated the Robo-AO Kepler Planetary Candidate Survey in 2012 to observe each Kepler exoplanet candidate host star with high angular resolution, visible light, laser adaptive optics (AOs) imaging. Our goal is to find nearby stars lying in Kepler's photometric apertures that are responsible for the relatively high probability of false-positive exoplanet detections and that cause underestimates of the size of transit radii. Our comprehensive survey will also shed light on the effects of stellar multiplicity on exoplanet properties and will identify rare exoplanetary architectures. In this second part of our ongoing survey, we observed an additional 969 Kepler planet candidate hosts and we report blended stellar companions up to {{Δ }}m≈ 6 that contribute to Kepler's measured light curves. We found 203 companions within ˜4″ of 181 of the Kepler stars, of which 141 are new discoveries. We measure the nearby star probability for this sample of Kepler planet candidate host stars to be 10.6% ± 1.1% at angular separations up to 2.″5, significantly higher than the 7.4% ± 1.0% probability discovered in our initial sample of 715 stars; we find the probability increases to 17.6% ± 1.5% out to a separation of 4.″0. The median position of Kepler Objects of Interest (KOIs) observed in this survey are 1.°1 closer to the galactic plane, which may account for some of the nearby star probability enhancement. We additionally detail 50 Keck AO images of Robo-AO observed KOIs in order to confirm 37 companions detected at a <5σ significance level and to obtain additional infrared photometry on higher significance detected companions.

  6. Use of satellite data in agricultural surveys

    NASA Technical Reports Server (NTRS)

    Hall, F. G.; Houston, A. G.

    1984-01-01

    The state-of-the-art of crop surveying by satellite is reviewed with an emphasis on the signature extension problem. Registration and preprocessing procedures are discussed with refereence to: normalization of the radiometric values of each scene for scene-to-scene differences; registration techniques, implemented at the NASA Johnson Space Center, capable of 0.5 pixel root-mean-square error; and current research in this direction. Data transformation and modeling techniques applied to the Landsat MSS images and a solution for the field-to-field variations of the greenness and brightness temporal trajectories are included. Finally, a review of the mixture decomposition method of labeling and estimating the areal proportions is given.

  7. Lessons learnt and results from the first survey of transiting exoplanet atmospheres using a multi-object spectrograph

    NASA Astrophysics Data System (ADS)

    Desert, Jean-Michel

    2015-12-01

    We present results from the first comprehensive survey program dedicated to probing transiting exoplanet atmospheres using transmission spectroscopy with a multi-object spectrograph (MOS). Our three-year survey focused on nine close-in giant planets for which the wavelength dependent transit depths in the visible were measured with Gemini/GMOS. In total, about 40 transits (200 hours) have been secured, with each exoplanet observed on average during four transits. This approach allows for a high spectrophotometric precision (200-500 ppm / 10 nm) and for a unique and reliable estimate of systematic uncertainties. We present the main results from this survey, the challenges faced by such an experiment, and the lessons learnt for future MOS observations and instrument designs. We show that the precision achieved by this survey permits us to distinguish hazy atmospheres from cloud-free scenarios. We lay out the challenges that are in front of us whilst preparing future atmospheric reconnaissance of habitable worlds with multi-object spectrographs.

  8. The Catalog of Earth-Like Exoplanet Survey Targets (CELESTA): A Database of Habitable Zones Around Nearby Stars

    NASA Astrophysics Data System (ADS)

    Chandler, Colin Orion; McDonald, Iain; Kane, Stephen R.

    2016-03-01

    Locating planets in circumstellar habitable zones (HZs) is a priority for many exoplanet surveys. Space-based and ground-based surveys alike require robust toolsets to aid in target selection and mission planning. We present the Catalog of Earth-Like Exoplanet Survey Targets (CELESTA), a database of HZs around 37,000 nearby stars. We calculated stellar parameters, including effective temperatures, masses, and radii, and we quantified the orbital distances and periods corresponding to the circumstellar HZs. We gauged the accuracy of our predictions by contrasting CELESTA’s computed parameters to observational data. We ascertain a potential return on investment by computing the number of HZs probed for a given survey duration. A versatile framework for extending the functionality of CELESTA into the future enables ongoing comparisons to new observations, and recalculations when updates to HZ models, stellar temperatures, or parallax data become available. We expect to upgrade and expand CELESTA using data from the Gaia mission as the data become available.

  9. Brouwer Award Lecture: Anelastic tides of close-in satellites and exoplanets

    NASA Astrophysics Data System (ADS)

    Ferraz-Mello, Sylvio

    2016-05-01

    This lecture reviews a new theory of the anelastic tides of celestial bodies in which the deformation of the body is the result of a Newtonian creep inversely proportional to the viscosity of the body and, along each radius, directly proportional to the distance from the actual surface of the body to the equilibrium. The first version of the theory (AAS/DDA 2012; CeMDA 2013), was restricted to homogeneous bodies. It was applied to many different bodies as the Moon, Mercury, super-Earths and hot Jupiters. An improved version (AAS/DDA 2014) included also the loss of angular momentum due to stellar winds and was applied to the study of the rotational evolution of active stars hosting massive companions. One more recent version (Folonier et al. AAS/DDA 2013; DPS 2015) allowed for the consideration of layered structures and was applied to Titan and Mercury. The resulting anelastic tides depend on the nature of the considered body. In the case of low-viscosity bodies (high relaxation factor), as gaseous planets and stars, the results are nearly the same of Darwin's theory. For instance, in these cases the dissipation grows proportionally to the tidal frequency. In the case of high-viscosity rocky satellites and planets (low relaxation factor), the results are structurally different: the dissipation varies with the tidal frequency following an inverse power law and the rotation may be driven to several attractors whose frequencies are 1/2, 1, 3/2, 2, 5/2,… times the orbital mean-motion, even when no permanent triaxiality exists.

  10. Satellite surveying for a Loran-C nonprecision approach

    NASA Technical Reports Server (NTRS)

    Mccall, Daryl L.

    1987-01-01

    Work has continued to site-in a Loran-C nonprecision approach at the Ohio University Gordon K. Bush Airport located in Albany, Ohio. A survey was performed using the Motorola Mini-Ranger Satellite Surveying System, which uses the Navy's TRANSIT satellites. This position was obtained using the point-position method only, that is the position was calculated from sequential Doppler measurements as the TRANSIT satellite's passed within view of the receiver's antenna. Another method, called translocation, can use differential techniques which provide better results. The accuracies obtained, however, are sufficient to site-in a Loran-C nonprecision approach.

  11. The Exoplanet Orbit Database

    NASA Astrophysics Data System (ADS)

    Wright, J. T.; Fakhouri, O.; Marcy, G. W.; Han, E.; Feng, Y.; Johnson, John Asher; Howard, A. W.; Fischer, D. A.; Valenti, J. A.; Anderson, J.; Piskunov, N.

    2011-04-01

    We present a database of well-determined orbital parameters of exoplanets, and their host stars' properties. This database comprises spectroscopic orbital elements measured for 427 planets orbiting 363 stars from radial velocity and transit measurements as reported in the literature. We have also compiled fundamental transit parameters, stellar parameters, and the method used for the planets discovery. This Exoplanet Orbit Database includes all planets with robust, well measured orbital parameters reported in peer-reviewed articles. The database is available in a searchable, filterable, and sortable form online through the Exoplanets Data Explorer table, and the data can be plotted and explored through the Exoplanet Data Explorer plotter. We use the Data Explorer to generate publication-ready plots, giving three examples of the signatures of exoplanet migration and dynamical evolution: We illustrate the character of the apparent correlation between mass and period in exoplanet orbits, the different selection biases between radial velocity and transit surveys, and that the multiplanet systems show a distinct semimajor-axis distribution from apparently singleton systems.

  12. High-cadence, High-contrast Imaging for Exoplanet Mapping: Observations of the HR 8799 Planets with VLT/SPHERE Satellite-spot-corrected Relative Photometry

    NASA Astrophysics Data System (ADS)

    Apai, Dániel; Kasper, Markus; Skemer, Andrew; Hanson, Jake R.; Lagrange, Anne-Marie; Biller, Beth A.; Bonnefoy, Mickaël; Buenzli, Esther; Vigan, Arthur

    2016-03-01

    Time-resolved photometry is an important new probe of the physics of condensate clouds in extrasolar planets and brown dwarfs. Extreme adaptive optics systems can directly image planets, but precise brightness measurements are challenging. We present VLT/SPHERE high-contrast, time-resolved broad H-band near-infrared photometry for four exoplanets in the HR 8799 system, sampling changes from night to night over five nights with relatively short integrations. The photospheres of these four planets are often modeled by patchy clouds and may show large-amplitude rotational brightness modulations. Our observations provide high-quality images of the system. We present a detailed performance analysis of different data analysis approaches to accurately measure the relative brightnesses of the four exoplanets. We explore the information in satellite spots and demonstrate their use as a proxy for image quality. While the brightness variations of the satellite spots are strongly correlated, we also identify a second-order anti-correlation pattern between the different spots. Our study finds that KLIP reduction based on principal components analysis with satellite-spot-modulated artificial-planet-injection-based photometry leads to a significant (˜3×) gain in photometric accuracy over standard aperture-based photometry and reaches 0.1 mag per point accuracy for our data set, the signal-to-noise ratio of which is limited by small field rotation. Relative planet-to-planet photometry can be compared between nights, enabling observations spanning multiple nights to probe variability. Recent high-quality relative H-band photometry of the b-c planet pair agrees to about 1%.

  13. The LEECH Exoplanet Imaging Survey: Orbit and Component Masses of the Intermediate-age, Late-type Binary NO UMa

    NASA Astrophysics Data System (ADS)

    Schlieder, Joshua E.; Skemer, Andrew J.; Maire, Anne-Lise; Desidera, Silvano; Hinz, Philip; Skrutskie, Michael F.; Leisenring, Jarron; Bailey, Vanessa; Defrère, Denis; Esposito, Simone; Strassmeier, Klaus G.; Weber, Michael; Biller, Beth A.; Bonnefoy, Mickaël; Buenzli, Esther; Close, Laird M.; Crepp, Justin R.; Eisner, Josh A.; Hofmann, Karl-Heinz; Henning, Thomas; Morzinski, Katie M.; Schertl, Dieter; Weigelt, Gerd; Woodward, Charles E.

    2016-02-01

    We present high-resolution Large Binocular Telescope LBTI/LMIRcam images of the spectroscopic and astrometric binary NO UMa obtained as part of the LBT Interferometer Exozodi Exoplanet Common Hunt exoplanet imaging survey. Our H-, Ks-, and L‧-band observations resolve the system at angular separations <0.″09. The components exhibit significant orbital motion over a span of ∼7 months. We combine our imaging data with archival images, published speckle interferometry measurements, and existing spectroscopic velocity data to solve the full orbital solution and estimate component masses. The masses of the K2.0 ± 0.5 primary and K6.5 ± 0.5 secondary are 0.83 ± 0.02 M⊙ and 0.64 ± 0.02 M⊙, respectively. We also derive a system distance of d = 25.87 ± 0.02 pc and revise the Galactic kinematics of NO UMa. Our revised Galactic kinematics confirm NO UMa as a nuclear member of the ∼500 Myr old Ursa Major moving group, and it is thus a mass and age benchmark. We compare the masses of the NO UMa binary components to those predicted by five sets of stellar evolution models at the age of the Ursa Major group. We find excellent agreement between our measured masses and model predictions with little systematic scatter between the models. NO UMa joins the short list of nearby, bright, late-type binaries having known ages and fully characterized orbits. Based on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP and IAC.

  14. A survey of satellite galaxies around NGC 4258

    SciTech Connect

    Spencer, Meghin; Loebman, Sarah; Yoachim, Peter

    2014-06-20

    We conduct a survey of satellite galaxies around the nearby spiral NGC 4258 by combining spectroscopic observations from the Apache Point Observatory 3.5 m telescope with Sloan Digital Sky Survey (SDSS) spectra. New spectroscopy is obtained for 15 galaxies. Of the 47 observed objects, we categorize 8 of them as probable satellites, 8 as possible satellites, and 17 as unlikely to be satellites. We do not speculate on the membership of the remaining 14 galaxies due to a lack of velocity and distance information. Radially integrating our best-fit NFW profile for NGC 4258 yields a total mass of 1.8 × 10{sup 12} M {sub ☉} within 200 kpc. We find that the angular distribution of the satellites appears to be random, and not preferentially aligned with the disk of NGC 4258. In addition, many of the probable satellite galaxies have blue u–r colors and appear to be star-forming irregulars in SDSS images; this stands in contrast to the low number of blue satellites in the Milky Way and M31 systems at comparable distances.

  15. Photometric survey of the irregular satellites

    NASA Astrophysics Data System (ADS)

    Grav, Tommy; Holman, Matthew J.; Gladman, Brett J.; Aksnes, Kaare

    2003-11-01

    We present BVRI colors of 13 jovian and 8 saturnian irregular satellites obtained with the 2.56 m Nordic Optical Telescope on La Palma, the 6.5 m Magellan Baade Telescope on La Campanas, and the 6.5 m MMT on Mt. Hopkins. The observations were performed from December 2001 to March 2002. The colors of the irregular satellites vary from grey to light red. We have arbitrarily divided the known irregular satellites into two classes based on their colors. One, the grey color class, has similar colors to the C-type asteroids, and the other, the light red color class, has colors similar to P/D-type asteroids. We also find at least one object, the jovian irregular J XXIII Kalyke, that has colors similar to the red colored Centaurs/TNOs, although its classification is insecure. We find that there is a correlation between the physical properties and dynamical properties of the irregular satellites. Most of the dynamical clusters have homogeneous colors, which points to single homogeneous progenitors being cratered or fragmented as the source of each individual cluster. The heterogeneously colored clusters are most easily explained by assuming that there are several dynamical clusters in the area, rather than just one, or that the parent body was a differentiated, heterogeneous body. By analyzing simple cratering/fragmentation scenarios, we show that the heterogeneous colored S IX Phoebe cluster, is most likely two different clusters, a grey colored cluster centered on S IX Phoebe and a light red colored cluster centered on S/2000 S 1. To which of these two clusters the remaining saturnian irregulars with inclinations close to 174° belong is not clear from our analysis, but determination of their colors should help constrain this. We also show through analysis of possible fragmentation and dispersion of the six known uranian irregulars that they most likely make up two clusters, one centered on U XVI Caliban and another centered on U XVII Sycorax. We further show that

  16. Exoplanets Galore!

    NASA Astrophysics Data System (ADS)

    2000-05-01

    -dwarf companions to HD 162020 and HD 202206 While about 40 giant exoplanet-candidates have so far been detected with masses in the range from 0.22 to 8.13 times that of Jupiter, only one companion object (in orbit around the star HD 114762) was known until now with a minimum mass between 10 and 15 times that of Jupiter. Such objects, referred to as "brown dwarfs" , are easier to detect than giant planets with similar periods because their greater mass induces larger velocity changes of the central star; they must therefore be very rare. This strongly points towards different formation/evolution processes for giant planets and stellar companions in the brown-dwarf domain. The brown-dwarf candidate around HD 162020 orbits this star (in constellation Scorpius - the Scorpion; visual magnitude 9.1; stellar type K2V) in 8.43 days on a moderately eccentric orbit. The inferred minimum mass of the companion is 13.7 times that of Jupiter. The second brown-dwarf candidate has a comparable minimum mass of 14.7 Jupiter masses. It orbits HD 202206 (in constellation Capricornus; visual magnitude 8.1; stellar type G6V) in 259 days and the orbit is fairly eccentric. The search for exoplanets: current status Most of the stars around which giant planets have been found so far show a significant excess of heavy elements in their atmosphere when compared to the majority of stars of the solar vicinity. This is also the case for most of the central stars of the eight new objects described here. This additional indication of an abnormal chemical composition of stars with giant gaseous planets provides a promising line for a better understanding of the mechanism(s) that ultimately lead to the formation of planetary systems. The high-precision radial-velocity survey with CORALIE in the southern hemisphere has the ambitious goal to make a complete inventory of giant exoplanets orbiting about 1600 stars in our galactic neighbourhood, all of which are relatively similar to our Sun. To date, 11 such exoplanets

  17. The MUSCLES Treasury Survey. II. Intrinsic LYα and Extreme Ultraviolet Spectra of K and M Dwarfs with Exoplanets*

    NASA Astrophysics Data System (ADS)

    Youngblood, Allison; France, Kevin; Parke Loyd, R. O.; Linsky, Jeffrey L.; Redfield, Seth; Schneider, P. Christian; Wood, Brian E.; Brown, Alexander; Froning, Cynthia; Miguel, Yamila; Rugheimer, Sarah; Walkowicz, Lucianne

    2016-06-01

    The ultraviolet (UV) spectral energy distributions (SEDs) of low-mass (K- and M-type) stars play a critical role in the heating and chemistry of exoplanet atmospheres, but are not observationally well-constrained. Direct observations of the intrinsic flux of the Lyα line (the dominant source of UV photons from low-mass stars) are challenging, as interstellar H i absorbs the entire line core for even the closest stars. To address the existing gap in empirical constraints on the UV flux of K and M dwarfs, the MUSCLES Hubble Space Telescope Treasury Survey has obtained UV observations of 11 nearby M and K dwarfs hosting exoplanets. This paper presents the Lyα and extreme-UV spectral reconstructions for the MUSCLES targets. Most targets are optically inactive, but all exhibit significant UV activity. We use a Markov Chain Monte Carlo technique to correct the observed Lyα profiles for interstellar absorption, and we employ empirical relations to compute the extreme-UV SED from the intrinsic Lyα flux in ˜100 Å bins from 100–1170 Å. The reconstructed Lyα profiles have 300 km s‑1 broad cores, while >1% of the total intrinsic Lyα flux is measured in extended wings between 300 and 1200 km s‑1. The Lyα surface flux positively correlates with the Mg ii surface flux and negatively correlates with the stellar rotation period. Stars with larger Lyα surface flux also tend to have larger surface flux in ions formed at higher temperatures, but these correlations remain statistically insignificant in our sample of 11 stars. We also present H i column density measurements for 10 new sightlines through the local interstellar medium. 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.

  18. The MUSCLES Treasury Survey. II. Intrinsic LYα and Extreme Ultraviolet Spectra of K and M Dwarfs with Exoplanets*

    NASA Astrophysics Data System (ADS)

    Youngblood, Allison; France, Kevin; Parke Loyd, R. O.; Linsky, Jeffrey L.; Redfield, Seth; Schneider, P. Christian; Wood, Brian E.; Brown, Alexander; Froning, Cynthia; Miguel, Yamila; Rugheimer, Sarah; Walkowicz, Lucianne

    2016-06-01

    The ultraviolet (UV) spectral energy distributions (SEDs) of low-mass (K- and M-type) stars play a critical role in the heating and chemistry of exoplanet atmospheres, but are not observationally well-constrained. Direct observations of the intrinsic flux of the Lyα line (the dominant source of UV photons from low-mass stars) are challenging, as interstellar H i absorbs the entire line core for even the closest stars. To address the existing gap in empirical constraints on the UV flux of K and M dwarfs, the MUSCLES Hubble Space Telescope Treasury Survey has obtained UV observations of 11 nearby M and K dwarfs hosting exoplanets. This paper presents the Lyα and extreme-UV spectral reconstructions for the MUSCLES targets. Most targets are optically inactive, but all exhibit significant UV activity. We use a Markov Chain Monte Carlo technique to correct the observed Lyα profiles for interstellar absorption, and we employ empirical relations to compute the extreme-UV SED from the intrinsic Lyα flux in ∼100 Å bins from 100–1170 Å. The reconstructed Lyα profiles have 300 km s‑1 broad cores, while >1% of the total intrinsic Lyα flux is measured in extended wings between 300 and 1200 km s‑1. The Lyα surface flux positively correlates with the Mg ii surface flux and negatively correlates with the stellar rotation period. Stars with larger Lyα surface flux also tend to have larger surface flux in ions formed at higher temperatures, but these correlations remain statistically insignificant in our sample of 11 stars. We also present H i column density measurements for 10 new sightlines through the local interstellar medium. 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.

  19. Satellite emission radio interferometric earth surveying series - GPS geodetic system

    NASA Technical Reports Server (NTRS)

    Macdoran, P. F.

    1979-01-01

    A concept called SERIES (satellite emissions radio interferometric earth surveying) which makes use of GPS (global positioning system) radio transmissions without any satellite modifications, is described. Through the use of very long baseline interferometry (VLBI) and its calibration methods, 0.5 to 3 cm three dimensional baseline accuracy can be achieved over distances of 2 to 200 km respectively, with only 2 hours of on-site data acquisition. Attention is given to such areas as: the radio flux equivalent of GPS transmissions, synthesized delay precision, transmission and frequency subsystem requirements, tropospheric and ionospheric errors. Applications covered include geodesy and seismic tectonics.

  20. Uncovering Exoplanets using Polarimetry

    NASA Astrophysics Data System (ADS)

    Stam, D. M.

    2012-12-01

    appears to be a strong tool both for the detection and the characterization of such cool exoplanets. Polarimetry helps their detection, because direct starlight is usually unpolarized, while starlight that has been reflected by a planet is usually polarized, especially at the phase angles favorable for observing exoplanets. Polarimetry thus improves the contrast between stars and their planets, and confirms that the detected object is indeed a planet. In my presentation, I will focus on the power of polarimetry for the characterization of exoplanets. This application is known from the derivation of the Venus cloud properties from the planet's polarized phase function by Hansen & Hovenier in 1974. Using numerically simulated flux and polarization phase functions and spectra for both gaseous and solid exoplanets, I will discuss the added value of polarimetry for exoplanet characterization as compared to flux observations, in particular for the retrieval of properties of clouds and hazes. Special attention will be given to the features in polarized phase functions that reveal the existence of liquid water clouds in the atmosphere (rainbows), even in the presence of ice clouds, or liquid water on the surface (glint) of an exoplanet. Using satellite data of the cloud and surface coverage of the Earth, calculated flux and polarization phase functions that should be observable from afar will be presented.

  1. NASA's Exoplanet Exploration Program

    NASA Astrophysics Data System (ADS)

    Devirian, Michael

    2009-01-01

    September 24, 2008 NASA has established the Exoplanet Exploration Program (ExEP) to conduct scientific investigations in one of the most exciting new fields of astronomy, the exploration and characterization of planets around other stars in search of those that might show signs of harboring life. In this paper, we will describe that program and how it is expected to work. Key to success in this field is the advancement of optical capabilities to unprecedented levels of precision and stability. The technology program conducted by ExEP will strive to achieve these advancements to enable near-term moderate scale missions and eventually lead to large flagship-class missions that will deeply probe the most promising earth-like planets for signs of biogenic activity. Significant opportunities for community participation in technology development will be available through NASA research solicitations that will call for technology advancements in specific areas. These developments will focus on challenges posed by a strategy for the progression of scientific investigations developed by the science community through bodies such as the Exoplanet Task Force, the Exoplanet Science Forum and ultimately the NRC Decadal Survey. ExEP will be advised in its tactical implementation of this strategy by Exoplanet Program Analysis Group (ExoPAG), which will engage a broad segment of the community in deliberation and then focus its reports through a core group appointed by NASA HQ. The coming decade offers opportunities for continued exoplanet investigations through ground observations, sub-orbital platforms and moderate scale space missions, and the anticipated process and timing of these opportunities will be described. The Exoplanet Exploration Program is managed for NASA at the Jet Propulsion Laboratory, California Institute of Technology.

  2. Optical design of the camera for Transiting Exoplanet Survey Satellite (TESS)

    NASA Astrophysics Data System (ADS)

    Chrisp, Michael; Clark, Kristin; Primeau, Brian; Dalpiaz, Michael; Lennon, Joseph

    2015-09-01

    The optical design of the wide field of view refractive camera with a 34 degree diagonal field for the TESS payload is described. This fast f/1.4 cryogenic camera, operating at -75°C, has no vignetting for maximum light gathering within the size and weight constraints. Four of these cameras capture full frames of star images for photometric searches of planet crossings. The optical design evolution, from the initial Petzval design, takes advantage of Forbes aspheres to develop a hybrid design form. This maximizes the correction from the two aspherics resulting in a reduction of average spot size by sixty percent in the final design. An external long wavelength pass filter has been replaced by an internal filter coating on a lens to save weight, and has been fabricated to meet the specifications. The stray light requirements are met by an extended lens hood baffle design, giving the necessary off-axis attenuation.

  3. Optical Design of the Camera for Transiting Exoplanet Survey Satellite (TESS)

    NASA Technical Reports Server (NTRS)

    Chrisp, Michael; Clark, Kristin; Primeau, Brian; Dalpiaz, Michael; Lennon, Joseph

    2015-01-01

    The optical design of the wide field of view refractive camera, 34 degrees diagonal field, for the TESS payload is described. This fast f/1.4 cryogenic camera, operating at -75 C, has no vignetting for maximum light gathering within the size and weight constraints. Four of these cameras capture full frames of star images for photometric searches of planet crossings. The optical design evolution, from the initial Petzval design, took advantage of Forbes aspheres to develop a hybrid design form. This maximized the correction from the two aspherics resulting in a reduction of average spot size by sixty percent in the final design. An external long wavelength pass filter was replaced by an internal filter coating on a lens to save weight, and has been fabricated to meet the specifications. The stray light requirements were met by an extended lens hood baffle design, giving the necessary off-axis attenuation.

  4. NASA's Missions for Exoplanet Exploration

    NASA Astrophysics Data System (ADS)

    Unwin, Stephen

    2014-05-01

    Exoplanets are detected and characterized using a range of observational techniques - including direct imaging, astrometry, transits, microlensing, and radial velocities. Each technique illuminates a different aspect of exoplanet properties and statistics. This diversity of approach has contributed to the rapid growth of the field into a major research area in only two decades. In parallel with exoplanet observations, major efforts are now underway to interpret the physical and atmospheric properties of exoplanets for which spectroscopy is now possible. In addition, comparative planetology probes questions of interest to both exoplanets and solar system studies. In this talk I describe NASA's activities in exoplanet research, and discuss plans for near-future missions that have reflected-light spectroscopy as a key goal. The WFIRST-AFTA concept currently under active study includes a major microlensing survey, and now includes a visible light coronagraph for exoplanet spectroscopy and debris disk imaging. Two NASA-selected community-led teams are studying probe-scale (< 1B) mission concepts for imaging and spectroscopy. These concepts complement existing NASA missions that do exoplanet science (such as transit spectroscopy and debris disk imaging with HST and Spitzer) or are under development (survey of nearby transiting exoplanets with TESS, and followup of the most important targets with transit spectroscopy on JWST), and build on the work of ground-based instruments such as LBTI and observing with HIRES on Keck. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Copyright 2014. California Institute of Technology. Government sponsorship acknowledged.

  5. The MUSCLES Treasury Survey: Intrinsic Lyα Profile Reconstructions and UV, X-ray, and Optical Correlations of Low-mass Exoplanet Host Stars

    NASA Astrophysics Data System (ADS)

    Youngblood, Allison; France, Kevin; Parke Loyd, R. O.

    2016-01-01

    UV stellar radiation can significantly impact planetary atmospheres through heating and photochemistry, even regulating production of potential biomarkers. Cool stars emit the majority of their UV radiation in the form of emission lines, and the incident UV radiation on close-in habitable-zone planets is significant. Lyα (1215.67 Å) dominates the 912 - 3200 Å spectrum of cool stars, but strong absorption from the interstellar medium (ISM) makes direct observations of the intrinsic Lyα emission of even nearby stars challenging. The MUSCLES Hubble Space Telescope Treasury Survey (Measurements of the Ultraviolet Spectral Characteristics of Low-mass Exoplanetary Systems) has completed observations of 7 M and 4 K stars hosting exoplanets (d < 22 pc) with simultaneous X-ray and ground-based optical spectroscopy for many of the targets. We have reconstructed the intrinsic Lyα profiles using an MCMC technique and used the results to estimate the extreme ultraviolet (100 - 911 Å) spectrum. We also present empirical relations between chromospheric UV and optical lines, e.g., Lyα, Mg II, Ca II H & K, and Hα, for use when direct UV observations of low-mass exoplanet host stars are not possible. The spectra presented here will be made publicly available through MAST to support exoplanet atmosphere modeling.

  6. The moving group targets of the seeds high-contrast imaging survey of exoplanets and disks: Results and observations from the first three years

    SciTech Connect

    Brandt, Timothy D.; Turner, Edwin L.; Janson, M.; Knapp, G. R.; Kuzuhara, Masayuki; McElwain, Michael W.; Schlieder, Joshua E.; Carson, J.; Biller, B.; Bonnefoy, M.; Brandner, W.; Wisniewski, John P.; Hashimoto, J.; Matsuo, T.; Dressing, C.; Moro-Martín, A.; Kudo, T.; Kusakabe, N.; Abe, L.; and others

    2014-05-01

    We present results from the first three years of observations of moving group (MG) targets in the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) high-contrast imaging survey of exoplanets and disks using the Subaru telescope. We achieve typical contrasts of ∼10{sup 5} at 1'' and ∼10{sup 6} beyond 2'' around 63 proposed members of nearby kinematic MGs. We review each of the kinematic associations to which our targets belong, concluding that five, β Pictoris (∼20 Myr), AB Doradus (∼100 Myr), Columba (∼30 Myr), Tucana-Horogium (∼30 Myr), and TW Hydrae (∼10 Myr), are sufficiently well-defined to constrain the ages of individual targets. Somewhat less than half of our targets are high-probability members of one of these MGs. For all of our targets, we combine proposed MG membership with other age indicators where available, including Ca II HK emission, X-ray activity, and rotation period, to produce a posterior probability distribution of age. SEEDS observations discovered a substellar companion to one of our targets, κ And, a late B star. We do not detect any other substellar companions, but do find seven new close binary systems, of which one still needs to be confirmed. A detailed analysis of the statistics of this sample, and of the companion mass constraints given our age probability distributions and exoplanet cooling models, will be presented in a forthcoming paper.

  7. The Moving Group Targets of the SEEDS High-contrast Imaging Survey of Exoplanets and Disks: Results and Observations from the First Three Years

    NASA Astrophysics Data System (ADS)

    Brandt, Timothy D.; Kuzuhara, Masayuki; McElwain, Michael W.; Schlieder, Joshua E.; Wisniewski, John P.; Turner, Edwin L.; Carson, J.; Matsuo, T.; Biller, B.; Bonnefoy, M.; Dressing, C.; Janson, M.; Knapp, G. R.; Moro-Martín, A.; Thalmann, C.; Kudo, T.; Kusakabe, N.; Hashimoto, J.; Abe, L.; Brandner, W.; Currie, T.; Egner, S.; Feldt, M.; Golota, T.; Goto, M.; Grady, C. A.; Guyon, O.; Hayano, Y.; Hayashi, M.; Hayashi, S.; Henning, T.; Hodapp, K. W.; Ishii, M.; Iye, M.; Kandori, R.; Kwon, J.; Mede, K.; Miyama, S.; Morino, J.-I.; Nishimura, T.; Pyo, T.-S.; Serabyn, E.; Suenaga, T.; Suto, H.; Suzuki, R.; Takami, M.; Takahashi, Y.; Takato, N.; Terada, H.; Tomono, D.; Watanabe, M.; Yamada, T.; Takami, H.; Usuda, T.; Tamura, M.

    2014-05-01

    We present results from the first three years of observations of moving group (MG) targets in the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) high-contrast imaging survey of exoplanets and disks using the Subaru telescope. We achieve typical contrasts of ~105 at 1'' and ~106 beyond 2'' around 63 proposed members of nearby kinematic MGs. We review each of the kinematic associations to which our targets belong, concluding that five, β Pictoris (~20 Myr), AB Doradus (~100 Myr), Columba (~30 Myr), Tucana-Horogium (~30 Myr), and TW Hydrae (~10 Myr), are sufficiently well-defined to constrain the ages of individual targets. Somewhat less than half of our targets are high-probability members of one of these MGs. For all of our targets, we combine proposed MG membership with other age indicators where available, including Ca II HK emission, X-ray activity, and rotation period, to produce a posterior probability distribution of age. SEEDS observations discovered a substellar companion to one of our targets, κ And, a late B star. We do not detect any other substellar companions, but do find seven new close binary systems, of which one still needs to be confirmed. A detailed analysis of the statistics of this sample, and of the companion mass constraints given our age probability distributions and exoplanet cooling models, will be presented in a forthcoming paper.

  8. The Moving Group Targets of the Seeds High-Contrast Imaging Survey of Exoplanets and Disks: Results and Observations from the First Three Years

    NASA Technical Reports Server (NTRS)

    Brandt, Timothy D.; Kuzuhara, Masayuki; McElwain, Michael W.; Schlieder, Joshua E.; Wisniewski, John P.; Turner, Edwin L.; Carson, J.; Matsuo, T.; Biller, B.; Bonnefoy, M.; Dressing, C.; Janson, M.; Knapp, G. R.; Moro-Martin, A.; Thalmann, C.; Kudo, T.; Kusakabe, N.; Hashimoto, J.; Abe, L.; Brandner, W.; Currie, T.; Egner, S.; Feldt, M.; Golota, T.; Goto, M.; Brady, C. A.; Guyon, O.; Hayano, Y.; Hyashi, M.; Hayashi, S.; Henning, T.; Hodapp, W.; Ishi, M.; Iye, M.; Kandori, R.

    2014-01-01

    We present results from the first three years of observations of moving group (MG) targets in the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) high-contrast imaging survey of exoplanets and disks using the Subaru telescope. We achieve typical contrasts of (is) approximately10(exp 5) at 1" and (is) approximately 10(exp 6) beyond 2" around 63 proposed members of nearby kinematic MGs. We review each of the kinematic associations to which our targets belong, concluding that five, beta Pictoris ((is) approximately 20 Myr), AB Doradus ((is) approximately 100 Myr), Columba ((is) approximately 30 Myr), Tucana-Horogium ((is) approximately 30 Myr), and TW Hydrae ((is) approximately 10 Myr), are sufficiently well-defined to constrain the ages of individual targets. Somewhat less than half of our targets are high-probability members of one of these MGs. For all of our targets, we combine proposed MG membership with other age indicators where available, including Ca ii HK emission, X-ray activity, and rotation period, to produce a posterior probability distribution of age. SEEDS observations discovered a substellar companion to one of our targets, kappa And, a late B star. We do not detect any other substellar companions, but do find seven new close binary systems, of which one still needs to be confirmed. A detailed analysis of the statistics of this sample, and of the companion mass constraints given our age probability distributions and exoplanet cooling models, will be presented in a forthcoming paper.

  9. First Temperate Exoplanet Sized Up

    NASA Astrophysics Data System (ADS)

    2010-03-01

    Combining observations from the CoRoT satellite and the ESO HARPS instrument, astronomers have discovered the first "normal" exoplanet that can be studied in great detail. Designated Corot-9b, the planet regularly passes in front of a star similar to the Sun located 1500 light-years away from Earth towards the constellation of Serpens (the Snake). "This is a normal, temperate exoplanet just like dozens we already know, but this is the first whose properties we can study in depth," says Claire Moutou, who is part of the international team of 60 astronomers that made the discovery. "It is bound to become a Rosetta stone in exoplanet research." "Corot-9b is the first exoplanet that really does resemble planets in our solar system," adds lead author Hans Deeg. "It has the size of Jupiter and an orbit similar to that of Mercury." "Like our own giant planets, Jupiter and Saturn, the planet is mostly made of hydrogen and helium," says team member Tristan Guillot, "and it may contain up to 20 Earth masses of other elements, including water and rock at high temperatures and pressures." Corot-9b passes in front of its host star every 95 days, as seen from Earth [1]. This "transit" lasts for about 8 hours, and provides astronomers with much additional information on the planet. This is fortunate as the gas giant shares many features with the majority of exoplanets discovered so far [2]. "Our analysis has provided more information on Corot-9b than for other exoplanets of the same type," says co-author Didier Queloz. "It may open up a new field of research to understand the atmospheres of moderate- and low-temperature planets, and in particular a completely new window in our understanding of low-temperature chemistry." More than 400 exoplanets have been discovered so far, 70 of them through the transit method. Corot-9b is special in that its distance from its host star is about ten times larger than that of any planet previously discovered by this method. And unlike all such

  10. ARIEL: Atmospheric Remote Sensing Infrared Exoplanet Large Survey. A proposal for the ESA Cosmic Vision M4

    NASA Astrophysics Data System (ADS)

    Pace, E.; Micela, G.; Ariel Team

    The Atmospheric Remote sensing Infrared Exoplanet Large survey (ARIEL) is a proposal in response to the call for a Medium-size mission opportunity in ESA’s Cosmic Vision 2015-2025 Science Programme for a launch in 2025 (M4). This mission will be devoted to observe spectroscopically in the IR a large population (hundreds to one thousand) of known planets in our Galaxy, opening a new discovery space in the field of extrasolar planet exploration and enabling a quantum leap in the understanding of the physics and chemistry of these far away worlds. The population of planets will include warm and hot gas‑giants, Neptunes and large terrestrial planets. The main ARIEL goal is the determination of the composition, formation and history of these planetary systems In order to fulfill the scientific goals of ARIEL, we propose the development of a 1‑meter class aperture space telescope, passively cooled to 70‑80K, to observe the combined light of stars and their planets, building on the current experience of transit and combined light observations with Hubble, Spitzer, and ground-based telescopes. While JWST and EELT will initiate a detailed mid- to high-resolution IR spectroscopic observation of a few tens of planets, this mission will extend the study to a much larger (an order of magnitude difference) representative population of extrasolar planets discovered by ESA GAIA, Cheops, PLATO, NASA Kepler II, TESS and from the ground. The statistical perspective provided by this mission, will allow us to address some of the fundamental questions of the Cosmic Vision programme: What are the conditions for planet formation and the emergence of life? ls our Solar System unique, rare or very common? How does the Solar System work?

  11. Exoplanet habitability.

    PubMed

    Seager, Sara

    2013-05-01

    The search for exoplanets includes the promise to eventually find and identify habitable worlds. The thousands of known exoplanets and planet candidates are extremely diverse in terms of their masses or sizes, orbits, and host star type. The diversity extends to new kinds of planets, which are very common yet have no solar system counterparts. Even with the requirement that a planet's surface temperature must be compatible with liquid water (because all life on Earth requires liquid water), a new emerging view is that planets very different from Earth may have the right conditions for life. The broadened possibilities will increase the future chances of discovering an inhabited world. PMID:23641111

  12. Satellite Emission Range Inferred Earth Survey (SERIES) project

    NASA Technical Reports Server (NTRS)

    Buennagel, L. A.; Macdoran, P. F.; Neilan, R. E.; Spitzmesser, D. J.; Young, L. E.

    1984-01-01

    The Global Positioning System (GPS) was developed by the Department of Defense primarily for navigation use by the United States Armed Forces. The system will consist of a constellation of 18 operational Navigation Satellite Timing and Ranging (NAVSTAR) satellites by the late 1980's. During the last four years, the Satellite Emission Range Inferred Earth Surveying (SERIES) team at the Jet Propulsion Laboratory (JPL) has developed a novel receiver which is the heart of the SERIES geodetic system designed to use signals broadcast from the GPS. This receiver does not require knowledge of the exact code sequence being transmitted. In addition, when two SERIES receivers are used differentially to determine a baseline, few cm accuracies can be obtained. The initial engineering test phase has been completed for the SERIES Project. Baseline lengths, ranging from 150 meters to 171 kilometers, have been measured with 0.3 cm to 7 cm accuracies. This technology, which is sponsored by the NASA Geodynamics Program, has been developed at JPL to meet the challenge for high precision, cost-effective geodesy, and to complement the mobile Very Long Baseline Interferometry (VLBI) system for Earth surveying.

  13. The Robo-AO KOI Survey: Laser Adaptive Optics Imaging of Every Kepler Exoplanet Candidate

    NASA Astrophysics Data System (ADS)

    Ziegler, Carl; Law, Nicholas M.; Baranec, Christoph; Morton, Tim; Riddle, Reed L.

    2016-01-01

    The Robo-AO Kepler Planetary Candidate Survey is observing every Kepler planet candidate host star (KOI) with laser adaptive optics imaging to hunt for blended nearby stars which may be physically associated companions. With the unparalleled efficiency provided by the first fully robotic adaptive optics system, we perform the critical search for nearby stars (0.15" to 4.0" separation with contrasts up to 6 magnitudes) that pollute the observed planetary transit signal, contributing to inaccurate planetary characteristics or astrophysical false positives. We present approximately 3300 high resolution observations of Kepler planetary hosts from 2012-2015, with ~500 observed nearby stars. We measure an overall nearby star probability rate of 16.2±0.8%. With this large dataset, we are uniquely able to explore broad correlations between multiple star systems and the properties of the planets which they host. We then use these clues for insight into the formation and evolution of these exotic systems. Several KOIs of particular interest will be discussed, including possible quadruple star systems hosting planets and updated properties for possible rocky planets orbiting in the habitable zone.

  14. Improved characterisation of exoplanets discovered in wide-field surveys: HAT-P-29b and HAT-P-31b

    NASA Astrophysics Data System (ADS)

    Rocchetto, M.; Fossey, S.

    2013-09-01

    In recent years a large population of exoplanets has been discovered thanks to ground-based surveys such as WASP and HATnet. These are typically relatively big planets in close orbits to their parent star that produce transit light curves with depths of up to a few percent which can be well observed using relatively smal-aperture ground-based telescopes. Due to the large number of planets discovered, systematic followup of most of these targets is often lacking. Moreover, in some discovery papers the characterisation of the planet is made with partial-transit follow-up light curves or relies entirely on the wide-field survey photometry, leading to relatively large uncertainties in the derived planetary parameters. We present followup photometry for two such cases, HAT-P-29b and HAT-P-31b, obtained with a 35-cm telescope based at UCL's University of London Observatory between 2011 and 2012. We find that our light curves are able to provide more accurate and/or precise parameters than those published. Follow-up observations are also important to monitor effects such as transit timing variations (TTVs), which can provide evidence for the presence of other planets in the system, and we explore the current limits on TTV detections for the two planets discussed here. The use of small-aperture telescopes provides an efficient and cost-effective way to improve the characterisation of known exoplanets, leading to an improvement in the statistical properties of these samples; and might also lead to the discovery of new exoplanets through TTV monitoring.

  15. EMI survey for maritime satellite, L-band, shipboard terminal

    NASA Technical Reports Server (NTRS)

    Taylor, R. E.; Hill, J. S.; Brandel, D. L.

    1974-01-01

    The United States Lines 15,690-ton commercial-container ship, American Alliance, was selected as lead ship for an onboard EMI survey prior to installation of L-Band shipboard terminals for operation with two, geostationary, maritime satellites. In general, the EMI survey revealed tolerable interference levels onboard ship: radiometer measurements indicate antenna-noise temperatures less than 70 K, at elevation angles of 5 deg and greater, at 1559 MHz, at the output terminals of the 1.2-m-diameter, parabolic-dish antenna for the L-Band shipboard terminal. Other EMI measurements include field intensity from 3 cm- and 10 cm-wavelength pulse radars, and conducted-emission tests of primary power lines to both onboard radars.

  16. Magsat - A new satellite to survey the earth's magnetic field

    NASA Technical Reports Server (NTRS)

    Mobley, F. F.; Eckard, L. D.; Fountain, G. H.; Ousley, G. W.

    1980-01-01

    The Magsat satellite was launched on Oct. 30, 1979 into a sun-synchronous dawn-dusk orbit, of 97 deg inclination, 350 km perigee, and 550 km apogee. It contains a precision vector magnetometer and a cesium-vapor scalar magnetometer at the end of a 6-m long graphite epoxy scissors boom. The magnetometers are accurate to 2 nanotesla. A pair of star cameras are used to define the body orientation to 10 arc sec rms. An 'attitude transfer system' measures the orientation of the magnetometer sensors relative to the star cameras to approximately 5 arc sec rms. The satellite position is determined to 70 meters rms by Doppler tracking. The overall objective is to determine each component of the earth's vector magnetic field to an accuracy of 6 nanotesla rms. The Magsat satellite gathers a complete picture of the earth's magnetic field every 12 hours. The vector components are sampled 16 times per second with a resolution of 0.5 nanotesla. The data will be used by the U.S. Geological Survey to prepare 1980 world magnetic field charts and to detect large-scale magnetic anomalies in the earth's crust for use in planning resource exploration strategy.

  17. The NASA Exoplanet Exploration Program

    NASA Astrophysics Data System (ADS)

    Hudgins, Douglas M.; Blackwood, Gary H.; Gagosian, John S.

    2015-12-01

    The NASA Exoplanet Exploration Program (ExEP) is chartered to implement the NASA space science goals of detecting and characterizing exoplanets and to search for signs of life. The ExEP manages space missions, future studies, technology investments, and ground-based science that either enables future missions or completes mission science. The exoplanet science community is engaged by the Program through Science Definition Teams and through the Exoplanet Program Analysis Group (ExoPAG). The ExEP includes the space science missions of Kepler, K2 , and the proposed WFIRST-AFTA that includes dark energy science, a widefield infrared survey, a microlensing survey for outer-exoplanet demographics, and a coronagraph for direct imaging of cool outer gas- and ice-giants around nearby stars. Studies of probe-scale (medium class) missions for a coronagraph (internal occulter) and starshade (external occulter) explore the trades of cost and science and provide motivation for a technology investment program to enable consideration of missions at the next decadal survey for NASA Astrophysics. Program elements include follow-up observations using the Keck Observatory, which contribute to the science yield of Kepler and K2, and include mid-infrared observations of exo-zodiacal dust by the Large Binocular Telescope Interferometer which provide parameters critical to the design and predicted science yield of the next generation of direct imaging missions. ExEP includes the NASA Exoplanet Science Institute which provides archives, tools, and professional education for the exoplanet community. Each of these program elements contribute to the goal of detecting and characterizing earth-like planets orbiting other stars, and seeks to respond to rapid evolution in this discovery-driven field and to ongoing programmatic challenges through engagement of the scientific and technical communities.

  18. The NASA Exoplanet Exploration Program

    NASA Astrophysics Data System (ADS)

    Hudgins, Douglas M.; Blackwood, Gary; Gagosian, John

    2014-11-01

    The NASA Exoplanet Exploration Program (ExEP) is chartered to implement the NASA space science goals of detecting and characterizing exoplanets and to search for signs of life. The ExEP manages space missions, future studies, technology investments, and ground-based science that either enables future missions or completes mission science. The exoplanet science community is engaged by the Program through Science Definition Teams and through the Exoplanet Program Analysis Group. The ExEP includes the space science missions of Kepler, K2, and the proposed WFIRST-AFTA that includes dark energy science, a widefield infrared survey, a microlensing survey for outer-exoplanet demographics, and a coronagraph for direct imaging of cool outer gas- and ice-giants around nearby stars. Studies of probe-scale (medium class) missions for a coronagraph (internal occulter) and starshade (external occulter) explore the trades of cost and science and provide motivation for a technology investment program to enable consideration of missions at the next decadal survey for NASA Astrophysics. Program elements include follow-up observations using the Keck Observatory which contribute to the science yield of Kepler and K2, and include mid-infrared observations of exo-zodiacal dust by the Large Binocular Telescope Interferometer which provide parameters critical to the design and predicted science yield of the next generation of direct imaging missions. ExEP includes the NASA Exoplanet Science Institute which provides archives, tools, and professional education for the exoplanet community. Each of these program elements contribute to the goal of detecting and characterizing earth-like planets orbiting other stars, and seeks to respond to rapid evolution in this discovery-driven field and to ongoing programmatic challenges through engagement of the scientific and technical communities.

  19. Exoplanets, extremophiles and habitability

    NASA Astrophysics Data System (ADS)

    Janot Pacheco, E.; Bernardes, L.

    2012-09-01

    Estimates of the average surface temperature and CO2 partial atmospheric pressure of already discovered exoplanets supposed to be in their Habitable Zone of their stars were surveyed from the Exoplanet Encyclopedia database. Moreover, since planetary surface temperature strongly depends on its albedo and geodynamic conditions, we have been feeding exoplanetary data into a comprehensive model of Earth's atmosphere to get better estimations. We also investigated the possible presence of "exomoons" belonging to giant planets capable of harbour dynamic stability and to retain atmospheric layers and keep geodynamic activity for long time spans. Collected information on biological data of micro-organisms classified as "extremophiles" indicate that such kind of microbial species could dwell in many of them. We thus propose an extension of the more astronomically defined "Habitable Zone" concept into the more astrobiologically "Extremophile Zone", taking into account other refined parameters allowing survival of more robust life forms.

  20. The SEEDS High-Contrast Imaging Survey: Exoplanet and Brown Dwarf Survey for Nearby Young Stars Dated with Gyrochronology and Activity Age Indicators

    NASA Astrophysics Data System (ADS)

    Kuzuhara, Masayuki; Tamura, Motohide; Helminiak, Kris; Mede, Kyle; Brandt, Timothy; Janson, Markus; Kandori, Ryo; Kudo, Tomoyuki; Kusakabe, Nobuhiko; Hashimoto, Jun

    2015-12-01

    The SEEDS campaign has successfully discovered and characterized exoplanets, brown dwarfs, and circumstellar disks since it began in 2009, via the direct imaging technique. The survey has targeted nearby young stars, as well as stars associated to star-forming regions, the Pleiades open cluster, moving groups, and debris disks. We selected the nearby young stars that have been dated with age indicators based on stellar rotation periods (i.e., gyrochronology) and chromoshperic/coronal activities. Of these, nearly 40 were observed, with ages mainly between 100 and 1000 Myr and distances less than 40 pc. Our observations typically attain the contrast of ~6 x 10-6 at 1'' and better than ~1 x 10-6 beyond 2'', enabling us to detect a planetary-mass companion even around such old stars. Indeed, the SEEDS team reported the discovery that the nearby Sun-like star GJ 504 hosts a Jovian companion GJ 504b, which has a mass of 3-8.5 Jupiter masses that is inferred according to the hot-start cooling models and our estimated system age of 100-510 Myr. The remaining observations out of the selected ~40 stars have resulted in no detection of additional planets or brown dwarf companions. Meanwhile, we have newly imaged a low-mass stellar companion orbiting the G-type star HIP 10321, for which the presence of companion was previously announced via radial velocity technique. The astrometry and radial velocity measurements are simultaneously analyzed to determine the orbit, providing constraints on the dynamical mass of both objects and stellar evolution models. Here we summarize our direct imaging observations for the nearby young stars dated with gyrochrolorogy and activity age indicators. Furthermore, we report the analysis for the HIP 10321 system with the imaged low-mass companion.

  1. Exoplanet's Atmospheres Characteristics vs. Exoplanet's Orbital Elements

    NASA Astrophysics Data System (ADS)

    Molaverdikhani, Karan

    2009-10-01

    400 years after Galileo Galilei was detected Jovian system, we know about 400 exoplanets in other stellar systems. But we identify just about their major properties like some of orbital elements, planet's radii or density. Also, there are many scientists who interested in searching for life or habitability on these planets. They are working in different ways such as planetary formation, planetary orbital stability or immigration, HabStars, composition of atmospheres, most probable zone in sky for exoplanets detection, etc. In this research we distinct and defined some main characteristics of terrestrial planet's atmospheres with surveying on solar system's planets and matching with current theorems on atmosphere formation. On the other hand, we were modeled Mars, Venus, Titan, single Hadley Earth and virtual Venus with different tilt angel (applying Global Circulation Modeling) to finding a critical limit on Polar Vortex formation in our last research. With extension this method on hypothetical terrestrial planets in constraint mass between 0.7 to 2.5 Earth's mass on Green Belt and applying host stars from 0.5 to 1.5 Sun's mass, we found some limitations on planet's atmosphere formation and estimation values of atmosphere's main characteristics.

  2. Small satellite survey mission to the second Earth moon

    NASA Astrophysics Data System (ADS)

    Pergola, P.

    2013-11-01

    This paper presents an innovative space mission devoted to the survey of the small Earth companion asteroid by means of nano platforms. Also known as the second Earth moon, Cruithne, is the target identified for the mission. Both the trajectory to reach the target and a preliminary spacecraft budget are here detailed. The idea is to exploit high efficient ion thrusters to reduce the propellant mass fraction in such a high total impulse mission (of the order of 1e6 Ns). This approach allows for a 100 kg class spacecraft with a very small Earth escape energy (5 km2/s2) to reach the destination in about 320 days. The 31% propellant mass fraction allows for a payload mass fraction of the order of 8% and this is sufficient to embark on such a small spacecraft a couple of nano-satellites deployed once at the target to carry out a complete survey of the asteroid. Two 2U Cubesats are here considered as representative payload, but also other scientific payloads or different platforms might be considered according with the specific mission needs. The small spacecraft used to transfer these to the target guarantees the manoeuvre capabilities during the interplanetary journey, the protection against radiations along the path and the telecommunication relay functions for the data transmission with Earth stations. The approach outlined in the paper offers reliable solutions to the main issues associated with a deep space nano-satellite mission thus allowing the exploitation of distant targets by means of these tiny spacecraft. The study presents an innovative general strategy for the NEO observation and Cruithne is chosen as test bench. This target, however, mainly for its relevant inclination, requires a relatively large propellant mass fraction that can be reduced if low inclination asteroids are of interest. This might increase the payload mass fraction (e.g. additional Cubesats and/or additional scientific payloads on the main bus) for the same 100 kg class mission.

  3. Exoplanets: The Hunt Continues!

    NASA Astrophysics Data System (ADS)

    2001-04-01

    Swiss Telescope at La Silla Very Successful Summary The intensive and exciting hunt for planets around other stars ( "exoplanets" ) is continuing with great success in both hemispheres. Today, an international team of astronomers from the Geneva Observatory and other research institutes [1] is announcing the discovery of no less than eleven new, planetary companions to solar-type stars, HD 8574, HD 28185, HD 50554, HD 74156, HD 80606, HD 82943, HD 106252, HD 141937, HD 178911B, HD 141937, among which two new multi-planet systems . The masses of these new objects range from slightly less than to about 10 times the mass of the planet Jupiter [2]. The new detections are based on measured velocity changes of the stars [3], performed with the CORALIE spectrometer on the Swiss 1.2-m Leonard Euler telescope at the ESO La Silla Observatory , as well as with instruments on telescopes at the Haute-Provence Observatory and on the Keck telescopes on Mauna Kea (Hawaii, USA). Some of the new planets are unusual: * a two-planet system (around the star HD 82943) in which one orbital period is nearly exactly twice as long as the other - cases like this (refered to as "orbital resonance") are well known in our own solar system; * another two-planet system (HD 74156), with a Jupiter-like planet and a more massive planet further out; * a planet with the most elongated orbit detected so far (HD 80606), moving between 5 and 127 million kilometers from the central star; * a giant planet moving in an orbit around its Sun-like central star that is very similar to the one of the Earth and whose potential satellites (in theory, at least) might be "habitable". At this moment, there are 63 know exoplanet candidates with minimum masses below 10 Jupiter masses, and 67 known objects with minimum masses below 17 Jupiter masses. The present team of astronomers has detected about half of these. PR Photo 13a/01 : Radial-velocity measurements of HD 82943, a two-planet system . PR Photo 13b/01 : Radial

  4. The alignment of SDSS satellites with the VPOS: effects of the survey footprint shape

    NASA Astrophysics Data System (ADS)

    Pawlowski, Marcel S.

    2016-02-01

    It is sometimes argued that the uneven sky coverage of the Sloan Digital Sky Survey (SDSS) biases the distribution of satellite galaxies discovered by it to align with the polar plane defined by the 11 brighter, classical Milky Way (MW) satellites. This might prevent the SDSS satellites from adding significance to the MW's vast polar structure (VPOS). We investigate whether this argument is valid by comparing the observed situation with model satellite distributions confined to the exact SDSS footprint area. We find that the SDSS satellites indeed add to the significance of the VPOS and that the survey footprint rather biases away from a close alignment between the plane fitted to the SDSS satellites and the plane fitted to the 11 classical satellites. Finding the observed satellite phase-space alignments of both the classical and SDSS satellites is an ˜5σ event with respect to an isotropic distribution. This constitutes a robust discovery of the VPOS and makes it more significant than the Great Plane of Andromeda (GPoA). Motivated by the GPoA, which consists of only about half of M31's satellites, we also estimate which fraction of the MW satellites is consistent with being part of an isotropic distribution. Depending on the underlying satellite plane width, only 2 to 6 out of the 27 considered MW satellites are expected to be drawn from isotropy, and an isotropic component of ≳50 per cent of the MW satellite population is excluded at 95 per cent confidence.

  5. Eccentricity of small exoplanets

    NASA Astrophysics Data System (ADS)

    Van Eylen, Vincent; Albrecht, Simon

    2015-12-01

    Solar system planets move on almost circular orbits. In strong contrast, many massive gas giant exoplanets travel on highly elliptical orbits, whereas the shape of the orbits of smaller, more terrestrial, exoplanets remained largely elusive. This is because the stellar radial velocity caused by these small planets is extremely challenging to measure. Knowing the eccentricity distribution in systems of small planets would be important as it holds information about the planet's formation and evolution. Furthermore the location of the habitable zone depends on eccentricity, and eccentricity also influences occurrence rates inferred for these planets because planets on circular orbits are less likely to transit. We make these eccentricity measurements of small planets using photometry from the Kepler satellite and utilizing a method relying on Kepler's second law, which relates the duration of a planetary transit to its orbital eccentricity, if the stellar density is known.I present a sample of 28 multi-planet systems with precise asteroseismic density measurements, which host 74 planets with an average radius of 2.6 R_earth. We find that the eccentricity of planets in these systems is low and can be described by a Rayleigh distribution with sigma = 0.049 +- 0.013. This is in full agreement with solar system eccentricities, but in contrast to the eccentricity distributions previously derived for exoplanets from radial velocity studies. I further report the first results on the eccentricities of over 50 Kepler single-planet systems, and compare them with the multi-planet systems. I close the talk by showing how transit durations help distinguish between false positives and true planets, and present six new planets.

  6. Exoplanets Galore!

    NASA Astrophysics Data System (ADS)

    2000-05-01

    Eight New Very Low-Mass Companions to Solar-Type Stars Discovered at La Silla The intensive and exciting hunt for planets around other stars ("exoplanets") is continuing with great success in both hemispheres. Today, a team of astronomers of the Geneva Observatory [1] are announcing the discovery of no less than eight new, very-low mass companions to solar-type stars. The masses of these objects range from less than that of planet Saturn to about 15 times that of Jupiter. The new results were obtained by means of high-precision radial-velocity measurements with the CORALIE spectrometer at the Swiss 1.2-m Leonhard Euler telescope at the ESO La Silla Observatory. An earlier account of this research programme is available as ESO Press Release 18/98. Recent views of this telescope and its dome are available below as PR Photos 13a-c/00. This observational method is based on the detection of changes in the velocity of the central star , due to the changing direction of the gravitational pull from an (unseen) exoplanet as it orbits the star. The evaluation of the measured velocity variations allows to deduce the planet's orbit , in particular the period and the distance from the star, as well as a minimum mass [2]. The characteristics of the new objects are quite diverse. While six of them are most likely bona-fide exoplanets , two are apparently very low-mass brown-dwarfs (objects of sub-stellar mass without a nuclear energy source in their interior). From the first discovery of an exoplanet around the star 51 Pegasi in 1995 (by Michel Mayor and Didier Queloz of the present team), the exoplanet count is now already above 40. "The present discoveries complete and enlarge our still preliminary knowledge of extra-solar planetary systems, as well as the transition between planets and `brown dwarfs'" , say Mayor and Queloz, on behalf of the Swiss team. An overview of the new objects ESO PR Photo 12/00 ESO PR Photo 12/00 [Preview - JPEG: 400 x 242 pix - 76k] [Normal - JPEG

  7. Combining Photometry from Kepler and TESS to Improve Short-period Exoplanet Characterization

    NASA Astrophysics Data System (ADS)

    Placek, Ben; Knuth, Kevin H.; Angerhausen, Daniel

    2016-07-01

    Planets emit thermal radiation and reflect incident light that they receive from their host stars. As a planet orbits its host star the photometric variations associated with these two effects produce very similar phase curves. If observed through only a single bandpass, this leads to a degeneracy between certain planetary parameters that hinder the precise characterization of such planets. However, observing the same planet through two different bandpasses gives much more information about the planet. Here we develop a Bayesian methodology for combining photometry from both Kepler and the Transiting Exoplanet Survey Satellite. In addition, we demonstrate via simulations that one can disentangle the reflected and thermally emitted light from the atmosphere of a hot-Jupiter as well as more precisely constrain both the geometric albedo and day-side temperature of the planet. This methodology can further be employed using various combinations of photometry from the James Webb Space Telescope, the Characterizing ExOplanet Satellite, or the PLATO mission.

  8. The GTC exoplanet transit spectroscopy survey. III. No asymmetries in the transit of CoRoT-29b

    NASA Astrophysics Data System (ADS)

    Pallé, E.; Chen, G.; Alonso, R.; Nowak, G.; Deeg, H.; Cabrera, J.; Murgas, F.; Parviainen, H.; Nortmann, L.; Hoyer, S.; Prieto-Arranz, J.; Nespral, D.; Cabrera Lavers, A.; Iro, N.

    2016-05-01

    Context. The launch of the exoplanet space missions obtaining exquisite photometry from space has resulted in the discovery of thousands of planetary systems with very different physical properties and architectures. Among them, the exoplanet CoRoT-29b was identified in the light curves the mission obtained in summer 2011, and presented an asymmetric transit light curve, which was tentatively explained via the effects of gravity darkening. Aims: Transits of CoRoT-29b are measured with precision photometry, to characterize the reported asymmetry in their transit shape. Methods: Using the OSIRIS spectrograph at the 10-m GTC telescope, we perform spectro-photometric differential observations, which allow us to both calculate a high-accuracy photometric light curve, and a study of the color-dependence of the transit. Results: After careful data analysis, we find that the previously reported asymmetry is not present in either of two transits, observed in July 2014 and July 2015 with high photometric precisions of 300 ppm over 5 min. Due to the relative faintness of the star, we do not reach the precision necessary to perform transmission spectroscopy of its atmosphere, but we see no signs of color-dependency of the transit depth or duration. Conclusions: We conclude that the previously reported asymmetry may have been a time-dependent phenomenon, which did not occur in more recent epochs. Alternatively, instrumental effects in the discovery data may need to be reconsidered. Light curves are 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/589/A62

  9. The GTC exoplanet transit spectroscopy survey. III. No asymmetries in the transit of CoRoT-29b

    NASA Astrophysics Data System (ADS)

    Pallé, E.; Chen, G.; Alonso, R.; Nowak, G.; Deeg, H.; Cabrera, J.; Murgas, F.; Parviainen, H.; Nortmann, L.; Hoyer, S.; Prieto-Arranz, J.; Nespral, D.; Cabrera Lavers, A.; Iro, N.

    2016-04-01

    Context. The launch of the exoplanet space missions obtaining exquisite photometry from space has resulted in the discovery of thousands of planetary systems with very different physical properties and architectures. Among them, the exoplanet CoRoT-29b was identified in the light curves the mission obtained in summer 2011, and presented an asymmetric transit light curve, which was tentatively explained via the effects of gravity darkening. Aims: Transits of CoRoT-29b are measured with precision photometry, to characterize the reported asymmetry in their transit shape. Methods: Using the OSIRIS spectrograph at the 10-m GTC telescope, we perform spectro-photometric differential observations, which allow us to both calculate a high-accuracy photometric light curve, and a study of the color-dependence of the transit. Results: After careful data analysis, we find that the previously reported asymmetry is not present in either of two transits, observed in July 2014 and July 2015 with high photometric precisions of 300 ppm over 5 min. Due to the relative faintness of the star, we do not reach the precision necessary to perform transmission spectroscopy of its atmosphere, but we see no signs of color-dependency of the transit depth or duration. Conclusions: We conclude that the previously reported asymmetry may have been a time-dependent phenomenon, which did not occur in more recent epochs. Alternatively, instrumental effects in the discovery data may need to be reconsidered. Light curves are 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/589/A62

  10. GTC OSIRIS transiting exoplanet atmospheric survey: detection of sodium in XO-2b from differential long-slit spectroscopy

    NASA Astrophysics Data System (ADS)

    Sing, D. K.; Huitson, C. M.; Lopez-Morales, M.; Pont, F.; Désert, J.-M.; Ehrenreich, D.; Wilson, P. A.; Ballester, G. E.; Fortney, J. J.; Lecavelier des Etangs, A.; Vidal-Madjar, A.

    2012-10-01

    We present two transits of the hot-Jupiter exoplanet XO-2b using the Gran Telescopio Canarias (GTC). The time series observations were performed using long-slit spectroscopy of XO-2 and a nearby reference star with the Optical System for Imaging and low Resolution Integrated Spectroscopy (OSIRIS) instrument, enabling differential spectrophotometric transit light curves capable of measuring the exoplanet's transmission spectrum. Two optical low-resolution grisms were used to cover the optical wavelength range from 3800 to 9300 Å. We find that sub-mmag-level slit losses between the target and reference star prevent full optical transmission spectra from being constructed, limiting our analysis to differential absorption depths over ˜1000 Å regions. Wider long slits or multi-object grism spectroscopy with wide masks will likely prove effective in minimizing the observed slit-loss trends. During both transits, we detect significant absorption in the planetary atmosphere of XO-2b using a 50-Å bandpass centred on the Na I doublet, with absorption depths of Δ(Rpl/R★)2 = 0.049 ± 0.017 per cent using the R500R grism and 0.047 ± 0.011 per cent using the R500B grism (combined 5.2σ significance from both transits). The sodium feature is unresolved in our low-resolution spectra, with detailed modelling also likely ruling out significant line-wing absorption over an ˜800 Å region surrounding the doublet. Combined with narrow-band photometric measurements, XO-2b is the first hot Jupiter with evidence for both sodium and potassium present in the planet's atmosphere. Based on observations made with the Gran Telescopio Canarias (GTC), installed in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias, in the island of La Palma, and part of the large European Southern Observatory (ESO) programme 182.C-2018.

  11. Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy

    NASA Astrophysics Data System (ADS)

    Wyttenbach, Aurélien; Ehrenreich, David

    2015-12-01

    The field of exoplanet atmospheres is booming thanks to (low-resolution) space-borne spectrographs and high-resolution (narrow-ranged) NIR spectrographs on ground-based 8m-class telescopes. Atmospheres are important because they are our observing window on the physical, chemical, and evolutionary processes occurring on exoplanets. Transiting exoplanets are the best suitable targets for atmospheric studies. Observing a transit in different filters or with a spectrograph reveals the transmission spectrum of the planet atmosphere. More than one decade of such observations allowed the exploration of these remote words by detecting some constituents of their atmospheres, but revealing also the presence of scattering hazes and clouds in several exoplanets preventing the detection of major chemical constituents at low to medium resolution even from space.Transit observations from the ground with stabilised high-resolution spectrograph, such HARPS, have key roles to play in this context. Observation of the hot-jupiter HD 189733b with HARPS allow the detection of sodium in the planet atmosphere. The high-resolution transmission spectra allowed to probe a new region high in the atmosphere and revealed rapid winds and a heating thermosphere. This new use of the famous planet hunter turned HARPS into a powerful exoplanet characterisation machine. It has the precision level of the Hubble Space Telescope, albeit at 20 higher resolution.A survey of a large set of known hot transiting exoplanets with HARPS and later with ESPRESSO will allow the detection of key tracers of atmospheric physics, chemistry, and evolution, above the scattering haze layers known to dominate low-resolution visible spectra of exoplanets.Such observation, in total sinergy with other technics, will rmly establish stabilised, high-resolution spectrographs on 4m telescopes as corner-stones for the characterisation of exoplanets. This is instrumental considering the upcoming surveys (NGTS,K2, CHEOPS, TESS

  12. SPLAT: Using Spectral Indices to Identify and Characterize Ultracool Stars, Brown Dwarfs and Exoplanets in Deep Surveys and as Companions to Nearby Stars

    NASA Astrophysics Data System (ADS)

    Aganze, Christian; Burgasser, Adam J.; Martin, Eduardo; Konopacky, Quinn; Masters, Daniel C.

    2016-06-01

    The majority of ultracool dwarf stars and brown dwarfs currently known were identified in wide-field red optical and infrared surveys, enabling measures of the local, typically isolated, population in a relatively shallow (<100 pc radius) volume. Constraining the properties of the wider Galactic population (scale height, radial distribution, Population II sources), and close brown dwarf and exoplanet companions to nearby stars, requires specialized instrumentation, such as high-contrast, coronagraphic spectrometers (e.g., Gemini/GPI, VLT/Sphere, Project 1640); and deep spectral surveys (e.g., HST/WFC3 parallel fields, Euclid). We present a set of quantitative methodologies to identify and robustly characterize sources for these specific populations, based on templates and tools developed as part of the SpeX Prism Library Analysis Toolkit. In particular, we define and characterize specifically-tuned sets spectral indices that optimize selection of cool dwarfs and distinguish rare populations (subdwarfs, young planetary-mass objects) based on low-resolution, limited-wavelength-coverage spectral data; and present a template-matching classification method for these instruments. We apply these techniques to HST/WFC3 parallel fields data in the WISPS and HST-3D programs, where our spectral index set allows high completeness and low contamination for searches of late M, L and T dwarfs to distances out to ~3 kpc.The material presented here is based on work supported by the National Aeronautics and Space Administration under Grant No. NNX15AI75G.

  13. Synthesizing Exoplanet Demographics: A Single Population of Long-period Planetary Companions to M Dwarfs Consistent with Microlensing, Radial Velocity, and Direct Imaging Surveys

    NASA Astrophysics Data System (ADS)

    Clanton, Christian; Gaudi, B. Scott

    2016-03-01

    We present the first study to synthesize results from five different exoplanet surveys using three independent detection methods: microlensing, radial velocity, and direct imaging. The constraints derived herein represent the most comprehensive picture of the demographics of large-separation (≳2 AU) planets orbiting the most common stars in our Galaxy that has been constructed to date. We assume a simple, joint power-law planet distribution function of the form {d}2{N}{{pl}}/(d{log} {m}p d{log} a)={ A }{({m}p/{M}{{Sat}})}α {(a/2.5{{AU}})}β with an outer cutoff radius of the separation distribution function of aout. Generating populations of planets from these models and mapping them into the relevant observables for each survey, we use actual or estimated detection sensitivities to determine the expected observations for each survey. Comparing with the reported results, we derive constraints on the parameters \\{α ,β ,{ A },{a}{{out}}\\} that describe a single population of planets that is simultaneously consistent with the results of microlensing, radial velocity, and direct imaging surveys. We find median and 68% confindence intervals of α =-{0.86}-0.19+0.21 (-{0.85}-0.19+0.21), β ={1.1}-1.4+1.9 ({1.1}-1.3+1.9), { A }={0.21}-0.15+0.20 {{dex}}-2 ({0.21}-0.15+0.20 {{dex}}-2), and {a}{{out}}={10}-4.7+26 AU ({12}-6.2+50 AU) assuming “hot-start” (“cold-start”) planet evolutionary models. These values are consistent with all current knowledge of planets on orbits beyond ∼2 AU around single M dwarfs.

  14. U. S. GEOLOGICAL SURVEY'S NATIONAL REAL-TIME HYDROLOGIC INFORMATION SYSTEM USING GOES SATELLITE TECHNOLOGY.

    USGS Publications Warehouse

    Shope, William G., Jr.

    1987-01-01

    The U. S. Geological Survey maintains the basic hydrologic data collection system for the United States. The Survey is upgrading the collection system with electronic communications technologies that acquire, telemeter, process, and disseminate hydrologic data in near real-time. These technologies include satellite communications via the Geostationary Operational Environmental Satellite, Data Collection Platforms in operation at over 1400 Survey gaging stations, Direct-Readout Ground Stations at nine Survey District Offices and a network of powerful minicomputers that allows data to be processed and disseminate quickly.

  15. Satellite Emission Radio Interferometric Earth Surveying (SERIES). [astrometry

    NASA Technical Reports Server (NTRS)

    Macdoran, P. F.

    1980-01-01

    Existing satellite radio emissions of the global positioning system were exploited as a resource for cost effective high accuracy geodetic measurements. System applications were directed toward crustal dynamics and earthquake research.

  16. PLANETESIMAL COMPOSITIONS IN EXOPLANET SYSTEMS

    SciTech Connect

    Johnson, Torrence V.; Mousis, Olivier; Lunine, Jonathan I.; Madhusudhan, Nikku

    2012-10-01

    We have used recent surveys of the composition of exoplanet host stars to investigate the expected composition of condensed material in planetesimals formed beyond the snow line in the circumstellar nebulae of these systems. Of the major solid-forming elements, C and O abundances (and particularly the C/O abundance ratio) strongly affect the amounts of volatile ices and refractory phases in icy planetesimals formed in these systems. This results from these elements' effects on the partitioning of O among gas, refractory solid and ice phases in the final condensate. The calculations use a self-consistent model for the condensation sequence of volatile ices from the nebula gas after refractory (silicate and metal) phases have condensed. The resultant mass fractions (compared to the total condensate) of refractory phases and ices were calculated for a range of nebular temperature structures and redox conditions. Planetesimals in systems with sub-solar C/O should be water ice-rich, with lower than solar mass fractions of refractory materials, while in super-solar C/O systems planetesimals should have significantly higher mass fractions of refractories, in some cases having little or no water ice. C-bearing volatile ices and clathrates also become increasingly important with increasing C/O depending on the assumed nebular temperatures. These compositional variations in early condensates in the outer portions of the nebula will be significant for the equivalent of the Kuiper Belt in these systems, icy satellites of giant planets, and the enrichment (over stellar values) of volatiles and heavy elements in giant planet atmospheres.

  17. A statistical analysis of seeds and other high-contrast exoplanet surveys: massive planets or low-mass brown dwarfs?

    SciTech Connect

    Brandt, Timothy D.; Spiegel, David S.; McElwain, Michael W.; Grady, C. A.; Turner, Edwin L.; Mede, Kyle; Kuzuhara, Masayuki; Schlieder, Joshua E.; Brandner, W.; Feldt, M.; Wisniewski, John P.; Abe, L.; Biller, B.; Carson, J.; Currie, T.; Egner, S.; Golota, T.; Guyon, O.; Goto, M.; Hashimoto, J.; and others

    2014-10-20

    We conduct a statistical analysis of a combined sample of direct imaging data, totalling nearly 250 stars. The stars cover a wide range of ages and spectral types, and include five detections (κ And b, two ∼60 M {sub J} brown dwarf companions in the Pleiades, PZ Tel B, and CD–35 2722B). For some analyses we add a currently unpublished set of SEEDS observations, including the detections GJ 504b and GJ 758B. We conduct a uniform, Bayesian analysis of all stellar ages using both membership in a kinematic moving group and activity/rotation age indicators. We then present a new statistical method for computing the likelihood of a substellar distribution function. By performing most of the integrals analytically, we achieve an enormous speedup over brute-force Monte Carlo. We use this method to place upper limits on the maximum semimajor axis of the distribution function derived from radial-velocity planets, finding model-dependent values of ∼30-100 AU. Finally, we model the entire substellar sample, from massive brown dwarfs to a theoretically motivated cutoff at ∼5 M {sub J}, with a single power-law distribution. We find that p(M, a)∝M {sup –0.65} {sup ±} {sup 0.60} a {sup –0.85} {sup ±} {sup 0.39} (1σ errors) provides an adequate fit to our data, with 1.0%-3.1% (68% confidence) of stars hosting 5-70 M {sub J} companions between 10 and 100 AU. This suggests that many of the directly imaged exoplanets known, including most (if not all) of the low-mass companions in our sample, formed by fragmentation in a cloud or disk, and represent the low-mass tail of the brown dwarfs.

  18. A Statistical Analysis of SEEDS and Other High-contrast Exoplanet Surveys: Massive Planets or Low-mass Brown Dwarfs?

    NASA Astrophysics Data System (ADS)

    Brandt, Timothy D.; McElwain, Michael W.; Turner, Edwin L.; Mede, Kyle; Spiegel, David S.; Kuzuhara, Masayuki; Schlieder, Joshua E.; Wisniewski, John P.; Abe, L.; Biller, B.; Brandner, W.; Carson, J.; Currie, T.; Egner, S.; Feldt, M.; Golota, T.; Goto, M.; Grady, C. A.; Guyon, O.; Hashimoto, J.; Hayano, Y.; Hayashi, M.; Hayashi, S.; Henning, T.; Hodapp, K. W.; Inutsuka, S.; Ishii, M.; Iye, M.; Janson, M.; Kandori, R.; Knapp, G. R.; Kudo, T.; Kusakabe, N.; Kwon, J.; Matsuo, T.; Miyama, S.; Morino, J.-I.; Moro-Martín, A.; Nishimura, T.; Pyo, T.-S.; Serabyn, E.; Suto, H.; Suzuki, R.; Takami, M.; Takato, N.; Terada, H.; Thalmann, C.; Tomono, D.; Watanabe, M.; Yamada, T.; Takami, H.; Usuda, T.; Tamura, M.

    2014-10-01

    We conduct a statistical analysis of a combined sample of direct imaging data, totalling nearly 250 stars. The stars cover a wide range of ages and spectral types, and include five detections (κ And b, two ~60 M J brown dwarf companions in the Pleiades, PZ Tel B, and CD-35 2722B). For some analyses we add a currently unpublished set of SEEDS observations, including the detections GJ 504b and GJ 758B. We conduct a uniform, Bayesian analysis of all stellar ages using both membership in a kinematic moving group and activity/rotation age indicators. We then present a new statistical method for computing the likelihood of a substellar distribution function. By performing most of the integrals analytically, we achieve an enormous speedup over brute-force Monte Carlo. We use this method to place upper limits on the maximum semimajor axis of the distribution function derived from radial-velocity planets, finding model-dependent values of ~30-100 AU. Finally, we model the entire substellar sample, from massive brown dwarfs to a theoretically motivated cutoff at ~5 M J, with a single power-law distribution. We find that p(M, a)vpropM -0.65 ± 0.60 a -0.85 ± 0.39 (1σ errors) provides an adequate fit to our data, with 1.0%-3.1% (68% confidence) of stars hosting 5-70 M J companions between 10 and 100 AU. This suggests that many of the directly imaged exoplanets known, including most (if not all) of the low-mass companions in our sample, formed by fragmentation in a cloud or disk, and represent the low-mass tail of the brown dwarfs. Based on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.

  19. Discovery and Spectroscopic Follow-up of Milky Way Satellites in the Dark Energy Survey

    NASA Astrophysics Data System (ADS)

    Li, Ting

    2016-01-01

    A complete census of Milky Way satellite galaxies provides crucial tests of both galaxy formation models and the Lambda-Cold Dark Matter theoretical paradigm. Wide-field imaging survey data from the first two year of the Dark Energy Survey (DES) have recently been used to discover many new Milky Way satellites, nearly doubling the number of known satellites. In this talk, I will describe the new dwarf galaxy candidates found in DES. I will also discuss the latest results from spectroscopic follow-up observations on some of the candidates using the Magellan, VLT, and AAT telescopes.

  20. Exoplanet environments to harbour extremophile life

    NASA Astrophysics Data System (ADS)

    Janot-Pacheco, Eduardo; Lage, Claudia A. S.; Lima, Ivan G. P.

    2010-02-01

    In this contribution, we estimate the temperature at the surface of known exoplanets and of their putative satellites for two albedo extreme cases (Venus and Mars) and present a selection of extremophiles living on Earth that can live under those conditions. We examine also the possibility of survival of microorganisms in planetary systems of variable stars.

  1. Polarimetry for rocky exoplanet characterization

    NASA Astrophysics Data System (ADS)

    Stam, Daphne; Karalidi, Theodora

    2013-04-01

    polarized, especially at planetary phase angles around 90 degrees, that are favorable for observing exoplanets. Polarimetry thus improves the contrast between stars and their planets, and confirms that the detected object is indeed a planet. Polarimetry is also invaluable for the characterization of exoplanets. This application is known from the derivation of the Venus cloud properties from the planet's polarized phase function by Hansen & Hovenier in 1974. Using numerically simulated flux and polarization phase functions and spectra for rocky exoplanets, I will discuss the added value of polarimetry for exoplanet characterization as compared to flux observations, in particular for the retrieval of properties of clouds and hazes. Special attention will be given to the features in polarized phase functions that reveal the existence of liquid water clouds in an exoplanet's atmosphere (rainbows), even in the presence of ice clouds. Using satellite data of the cloud and surface coverage of the Earth, calculated flux and polarization phase functions that should be observable from afar will be presented.

  2. A Survey of the Utility of Satellite Magnetometer Data for Application to Solid-earth Geophysical and Geological Studies

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A survey of potential users of low altitude satellite magnetic measurements for solid-earth and geological studies was conducted. The principal objectives of this survey were to: document the utility and application of the data and resultant products obtained from such a satellite mission, and establish a users committee for the proposed low altitude vector magnetometer satellite.

  3. Satellites

    SciTech Connect

    Burns, J.A.; Matthews, M.S.

    1986-01-01

    The present work is based on a conference: Natural Satellites, Colloquium 77 of the IAU, held at Cornell University from July 5 to 9, 1983. Attention is given to the background and origins of satellites, protosatellite swarms, the tectonics of icy satellites, the physical characteristics of satellite surfaces, and the interactions of planetary magnetospheres with icy satellite surfaces. Other topics include the surface composition of natural satellites, the cratering of planetary satellites, the moon, Io, and Europa. Consideration is also given to Ganymede and Callisto, the satellites of Saturn, small satellites, satellites of Uranus and Neptune, and the Pluto-Charon system.

  4. The Architecture of Exoplanets

    NASA Astrophysics Data System (ADS)

    Hatzes, Artie P.

    2016-05-01

    Prior to the discovery of exoplanets our expectations of their architecture were largely driven by the properties of our solar system. We expected giant planets to lie in the outer regions and rocky planets in the inner regions. Planets should probably only occupy orbital distances 0.3-30 AU from the star. Planetary orbits should be circular, prograde and in the same plane. The reality of exoplanets have shattered these expectations. Jupiter-mass, Neptune-mass, Superearths, and even Earth-mass planets can orbit within 0.05 AU of the stars, sometimes with orbital periods of less than one day. Exoplanetary orbits can be eccentric, misaligned, and even in retrograde orbits. Radial velocity surveys gave the first hints that the occurrence rate increases with decreasing mass. This was put on a firm statistical basis with the Kepler mission that clearly demonstrated that there were more Neptune- and Superearth-sized planets than Jupiter-sized planets. These are often in multiple, densely packed systems where the planets all orbit within 0.3 AU of the star, a result also suggested by radial velocity surveys. Exoplanets also exhibit diversity along the main sequence. Massive stars tend to have a higher frequency of planets ( ≈ 20-25 %) that tend to be more massive ( M≈ 5-10 M_{Jup}). Giant planets around low mass stars are rare, but these stars show an abundance of small (Neptune and Superearth) planets in multiple systems. Planet formation is also not restricted to single stars as the Kepler mission has discovered several circumbinary planets. Although we have learned much about the architecture of planets over the past 20 years, we know little about the census of small planets at relatively large ( a>1 AU) orbital distances. We have yet to find a planetary system that is analogous to our own solar system. The question of how unique are the properties of our own solar system remains unanswered. Advancements in the detection methods of small planets over a wide range

  5. Optical Survey of the Tumble Rates of Retired GEO Satellites

    NASA Astrophysics Data System (ADS)

    Binz, C.; Davis, M.; Kelm, B.; Moore, C.

    2014-09-01

    The Naval Research Lab (NRL) and the Defense Advanced Research Projects Agency (DARPA) have made significant progress toward robotic rendezvous and docking between spacecraft, however the long-term attitude motion evolution of uncontrolled resident space objects has never been well-characterized. This effort set out to identify the motion exhibited in retired satellites at or near geosynchronous orbit (GEO). Through analysis of the periodic structure of observed reflected light curves, estimated tumble rates were determined for several retired satellites, typically in a super-GEO disposal orbit. The NRL's 1-meter telescope at Midway Research Center was used to track and observe the objects while the sun-satellite-observer geometry was most favorable; typically over a one- to two-hour period, repeated multiple times over the course of weeks. By processing each image with calibration exposures, the relative apparent magnitude of the brightness of the object over time was determined. Several tools, including software developed internally, were used for frequency analysis of the brightness curves. Results show that observed satellites generally exhibit a tumble rate well below the notional bounding case of one degree per second. When harmonics are found to exist in the data, modeling and simulation of the optical characteristics of the satellite can help to resolve ambiguities. This process was validated on spacecraft for which an attitude history is known, and agreement was found.

  6. The VLT/NaCo large program to probe the occurrence of exoplanets and brown dwarfs at wide orbits. II. Survey description, results, and performances

    NASA Astrophysics Data System (ADS)

    Chauvin, G.; Vigan, A.; Bonnefoy, M.; Desidera, S.; Bonavita, M.; Mesa, D.; Boccaletti, A.; Buenzli, E.; Carson, J.; Delorme, P.; Hagelberg, J.; Montagnier, G.; Mordasini, C.; Quanz, S. P.; Segransan, D.; Thalmann, C.; Beuzit, J.-L.; Biller, B.; Covino, E.; Feldt, M.; Girard, J.; Gratton, R.; Henning, T.; Kasper, M.; Lagrange, A.-M.; Messina, S.; Meyer, M.; Mouillet, D.; Moutou, C.; Reggiani, M.; Schlieder, J. E.; Zurlo, A.

    2015-01-01

    Context. Young, nearby stars are ideal targets for direct imaging searches for giant planets and brown dwarf companions. After the first-imaged planet discoveries, vast efforts have been devoted to the statistical analysis of the occurence and orbital distributions of giant planets and brown dwarf companions at wide (≥5-6 AU) orbits. Aims: In anticipation of the VLT/SPHERE planet-imager, guaranteed-time programs, we have conducted a preparatory survey of 86 stars between 2009 and 2013 to identify new faint comoving companions to ultimately analyze the occurence of giant planets and brown dwarf companions at wide (10-2000 AU) orbits around young, solar-type stars. Methods: We used NaCo at VLT to explore the occurrence rate of giant planets and brown dwarfs between typically 0.1 and 8''. Diffraction-limited observations in H-band combined with angular differential imaging enabled us to reach primary star-companion brightness ratios as small as 10-6 at 1.5''. Repeated observations at several epochs enabled us to discriminate comoving companions from background objects. Results: During our survey, twelve systems were resolved as new binaries, including the discovery of a new white dwarf companion to the star HD 8049. Around 34 stars, at least one companion candidate was detected in the observed field of view. More than 400 faint sources were detected; 90% of them were in four crowded fields. With the exception of HD 8049 B, we did not identify any new comoving companions. The survey also led to spatially resolved images of the thin debris disk around HD 61005 that have been published earlier. Finally, considering the survey detection limits, we derive a preliminary upper limit on the frequency of giant planets for the semi-major axes of [10, 2000] AU: typically less than 15% between 100 and 500 AU and less than 10% between 50 and 500 AU for exoplanets that are more massive than 5 MJup and 10 MJup respectively, if we consider a uniform input distribution and a

  7. ECLIPSING BINARY SCIENCE VIA THE MERGING OF TRANSIT AND DOPPLER EXOPLANET SURVEY DATA-A CASE STUDY WITH THE MARVELS PILOT PROJECT AND SuperWASP

    SciTech Connect

    Fleming, Scott W.; Ge Jian; De Lee, Nathan M.; Zhao Bo; Wan Xiaoke; Guo Pengcheng; Maxted, Pierre F. L.; Anderson, David R.; Hellier, Coel; Hebb, Leslie; Stassun, Keivan G.; Cargile, Phillip A.; Gary, Bruce; Ghezzi, Luan; Wisniewski, John; Porto de Mello, G. F.; Ferreira, Leticia; West, Richard G.; Mahadevan, Suvrath; Pollacco, Don

    2011-08-15

    Exoplanet transit and Doppler surveys discover many binary stars during their operation that can be used to conduct a variety of ancillary science. Specifically, eclipsing binary stars can be used to study the stellar mass-radius relationship and to test predictions of theoretical stellar evolution models. By cross-referencing 24 binary stars found in the MARVELS Pilot Project with SuperWASP photometry, we find two new eclipsing binaries, TYC 0272-00458-1 and TYC 1422-01328-1, which we use as case studies to develop a general approach to eclipsing binaries in survey data. TYC 0272-00458-1 is a single-lined spectroscopic binary for which we calculate a mass of the secondary and radii for both components using reasonable constraints on the primary mass through several different techniques. For a primary mass of M{sub 1} = 0.92 {+-} 0.1 M{sub sun}, we find M{sub 2} = 0.610 {+-} 0.036 M{sub sun}, R{sub 1} = 0.932 {+-} 0.076 R{sub sun}, and R{sub 2} = 0.559 {+-} 0.102 R{sub sun}, and find that both stars have masses and radii consistent with model predictions. TYC 1422-01328-1 is a triple-component system for which we can directly measure the masses and radii of the eclipsing pair. We find that the eclipsing pair consists of an evolved primary star (M{sub 1} = 1.163 {+-} 0.034 M{sub sun}, R{sub 1} = 2.063 {+-} 0.058 R{sub sun}) and a G-type dwarf secondary (M{sub 2} = 0.905 {+-} 0.067 M{sub sun}, R{sub 2} = 0.887 {+-} 0.037 R{sub sun}). We provide the framework necessary to apply this analysis to much larger data sets.

  8. Astrometric exoplanet detection with Gaia

    SciTech Connect

    Perryman, Michael; Hartman, Joel; Bakos, Gáspár Á.; Lindegren, Lennart

    2014-12-10

    We provide a revised assessment of the number of exoplanets that should be discovered by Gaia astrometry, extending previous studies to a broader range of spectral types, distances, and magnitudes. Our assessment is based on a large representative sample of host stars from the TRILEGAL Galaxy population synthesis model, recent estimates of the exoplanet frequency distributions as a function of stellar type, and detailed simulation of the Gaia observations using the updated instrument performance and scanning law. We use two approaches to estimate detectable planetary systems: one based on the signal-to-noise ratio of the astrometric signature per field crossing, easily reproducible and allowing comparisons with previous estimates, and a new and more robust metric based on orbit fitting to the simulated satellite data. With some plausible assumptions on planet occurrences, we find that some 21,000 (±6000) high-mass (∼1-15M {sub J}) long-period planets should be discovered out to distances of ∼500 pc for the nominal 5 yr mission (including at least 1000-1500 around M dwarfs out to 100 pc), rising to some 70,000 (±20, 000) for a 10 yr mission. We indicate some of the expected features of this exoplanet population, amongst them ∼25-50 intermediate-period (P ∼ 2-3 yr) transiting systems.

  9. Use of the transect method in satellite survey missions with application to the infrared astronomical satellite /IRAS/

    NASA Technical Reports Server (NTRS)

    Mclaughlin, W. I.; Lundy, S. A.; Ling, H. Y.; Stroberg, M. W.

    1980-01-01

    The coverage of the celestial sphere or the surface of the earth with a narrow-field instrument onboard a satellite can be described by a set of swaths on the sphere. A transect is a curve on this sphere constructed to sample the coverage. At each point on the transect the number of times that the field-of-view of the instrument has passed over the point is recorded. This information is conveniently displayed as an integer-valued histogram over the length of the transect. The effectiveness of the transect method for a particular observing plan and the best placement of the transects depends upon the structure of the set of observations. Survey missions are usually characterized by a somewhat parallel alignment of the instrument swaths. Using autocorrelation and cross-correlation functions among the histograms the structure of a survey has been analyzed into two components, and each is illustrated by a simple mathematical model. The complex, all-sky survey to be performed by the Infrared Astronomical Satellite (IRAS) is synthesized in some detail utilizing the objectives and constraints of that mission. It is seen that this survey possesses the components predicted by the simple models and this information is useful in characterizing the properties of the IRAS survey and the placement of the transects as a function of celestial latitude and certain structural properties of the coverage.

  10. Contributions of the Pulkovo and Kharkiv Scientific Schools to the search for exoplanets and low-mass dark satellites of stars

    NASA Astrophysics Data System (ADS)

    Zakhozhay, V. A.; Gnedin, Yu. N.; Shakht, N. A.

    2010-12-01

    This article is devoted to the Pulkovo astronomer, Prof. Aleksandr Nikolaevich Deich (Deutsch) (1899-1986), on the 110-th anniversary of his birth. Deich is known as the founder of the Pulkovo program for observing stars with invisible companions, as well as for his research on the star 61 Cyg, which was suspected, in his time, of having invisible companions with the masses of planets. Astrometric observations on the long focus astrograph and searches for exoplanets of nearby stars are reviewed. Modern methods of searching for exoplanets are summarized briefly. Instrument designs proposed by astronomers at Kharkiv (Scientific Research Institute of Astronomy at Kharkiv National University, NIIA KhNU) and Kazan (Institute of Astronomy, Kazan State University, AO KGU) for use in the search for low-mass dark components of stars are discussed. Examples are given of confirmations of invisible companions of stars which were first discovered by observation. A number of theoretical results on this topic from Kharkiv National University (Scientific Research Institute of Astronomy at Kharkiv and the Dept. of Astronomy) are noted.

  11. CONSTRAINTS ON OH MEGAMASER EXCITATION FROM A SURVEY OF OH SATELLITE LINES

    SciTech Connect

    McBride, James; Heiles, Carl; Elitzur, Moshe

    2013-09-01

    We report the results of a full-Stokes survey of all four 18 cm OH lines in 77 OH megamasers (OHMs) using the Arecibo Observatory. This is the first survey of OHMs that included observations of the OH satellite lines; only four of the 77 OHMs have existing satellite line observations in the literature. Satellite line emission is detected in five sources, three of which are redetections of previously published sources. The two sources with new detections of satellite line emission are IRAS F10173+0829, which was detected at 1720 MHz, and IRAS F15107+0724, for which both the 1612 MHz and 1720 MHz lines were detected. In IRAS F15107+0724, the satellite lines are partially conjugate, as 1720 MHz absorption and 1612 MHz emission have the same structure at some velocities within the source, along with additional broader 1612 MHz emission. This is the first observed example of conjugate satellite lines in an OHM. In the remaining sources, no satellite line emission is observed. The detections and upper limits are generally consistent with models of OHM emission in which all of the 18 cm OH lines have the same excitation temperature. There is no evidence for a significant population of strong satellite line emitters among OHMs.

  12. Molecular opacities for exoplanets

    PubMed Central

    Bernath, Peter F.

    2014-01-01

    Spectroscopic observations of exoplanets are now possible by transit methods and direct emission. Spectroscopic requirements for exoplanets are reviewed based on existing measurements and model predictions for hot Jupiters and super-Earths. Molecular opacities needed to simulate astronomical observations can be obtained from laboratory measurements, ab initio calculations or a combination of the two approaches. This discussion article focuses mainly on laboratory measurements of hot molecules as needed for exoplanet spectroscopy. PMID:24664921

  13. Molecular opacities for exoplanets.

    PubMed

    Bernath, Peter F

    2014-04-28

    Spectroscopic observations of exoplanets are now possible by transit methods and direct emission. Spectroscopic requirements for exoplanets are reviewed based on existing measurements and model predictions for hot Jupiters and super-Earths. Molecular opacities needed to simulate astronomical observations can be obtained from laboratory measurements, ab initio calculations or a combination of the two approaches. This discussion article focuses mainly on laboratory measurements of hot molecules as needed for exoplanet spectroscopy. PMID:24664921

  14. Spectroscopically Unlocking Exoplanet Characteristics

    NASA Astrophysics Data System (ADS)

    Lewis, Nikole

    2016-05-01

    Spectroscopy plays a critical role in a number of areas of exoplanet research. The first exoplanets were detected by precisely measuring Doppler shifts in high resolution (R ~ 100,000) stellar spectra, a technique that has become known as the Radial Velocity (RV) method. The RV method provides critical constraints on exoplanet masses, but is currently limited to some degree by robust line shape predictions. Beyond the RV method, spectroscopy plays a critical role in the characterization of exoplanets beyond their mass and radius. The Hubble Space Telescope has spectroscopically observed the atmospheres of exoplanets that transit their host stars as seen from Earth giving us key insights into atmospheric abundances of key atomic and molecular species as well as cloud optical properties. Similar spectroscopic characterization of exoplanet atmospheres will be carried out at higher resolution (R ~ 100-3000) and with broader wavelength coverage with the James Webb Space Telescope. Future missions such as WFIRST that seek to the pave the way toward the detection and characterization of potentially habitable planets will have the capability of directly measuring the spectra of exoplanet atmospheres and potentially surfaces. Our ability to plan for and interpret spectra from exoplanets relies heavily on the fidelity of the spectroscopic databases available and would greatly benefit from further laboratory and theoretical work aimed at optical properties of atomic, molecular, and cloud/haze species in the pressure and temperature regimes relevant to exoplanet atmospheres.

  15. Spectroscopy of Kepler Candidate Exoplanet Host Stars

    NASA Astrophysics Data System (ADS)

    Everett, Mark E.; Howell, Steve B.; Silva, David R.; Szkody, Paula

    2014-02-01

    Currently the NASA Kepler Mission has identified 3449 exoplanet candidates, one third with estimated radii R_p<2.5R_oplus and orbiting faint (m_Kep>14.5) host stars. The NASA sponsored Kepler Follow-up Program is focusing on small exoplanet candidates (R_p<2.5R_oplus) and those in habitable zone orbits. Planet radii estimates depend on estimates of host star radii. Based on spectra previously obtained at the KPNO Mayall 4-m for 220 stars with candidate exoplanets, Everett et al. (2013) have shown that many host stars are larger than originally assumed (up to factor of 2). Therefore, the exoplanet candidates they host must be larger than originally assumed, which conversely reduces the number of known Earth- sized exoplanet candidates. Determination of the frequency of such Earth-sized planets is a cornerstone Kepler mission objective and of keen general interest. These Mayall spectra were also used to confirm the Buchhave et al. (2012) result that exoplanet candidates larger than 4R_oplus in short-period orbits are preferentially associated with host stars with solar or higher metallicity, using a fainter and larger sample of stars than Buchhave et al. In short, followup Mayall optical spectroscopy is critical to confirming the detection of Earth-sized exoplanets, a Kepler cornerstone goal, as well as characterizing the relationship between host star properties and planetary system properties. Here, we propose to continue our reconnaissance survey with a focus on the smallest (most rare) exoplanet candidates orbiting the faintest Kepler host stars.

  16. Estimating optimal sampling unit sizes for satellite surveys

    NASA Technical Reports Server (NTRS)

    Hallum, C. R.; Perry, C. R., Jr.

    1984-01-01

    This paper reports on an approach for minimizing data loads associated with satellite-acquired data, while improving the efficiency of global crop area estimates using remotely sensed, satellite-based data. Results of a sampling unit size investigation are given that include closed-form models for both nonsampling and sampling error variances. These models provide estimates of the sampling unit sizes that effect minimal costs. Earlier findings from foundational sampling unit size studies conducted by Mahalanobis, Jessen, Cochran, and others are utilized in modeling the sampling error variance as a function of sampling unit size. A conservative nonsampling error variance model is proposed that is realistic in the remote sensing environment where one is faced with numerous unknown nonsampling errors. This approach permits the sampling unit size selection in the global crop inventorying environment to be put on a more quantitative basis while conservatively guarding against expected component error variances.

  17. Assessing Usefulness of High-Resolution Satellite Imagery (HRSI) for Re-Survey of Cadastral Maps

    NASA Astrophysics Data System (ADS)

    Rao, S. S.; Sharma, J. R.; Rajashekar, S. S.; Rao, D. S. P.; Arepalli, A.; Arora, V.; Kuldeep; Singh, R. P.; Kanaparthi, M.

    2014-11-01

    The Government of India has initiated "National Land Records Modernization Programme (NLRMP)" with emphasis to modernize management of land records, minimize scope of land/property disputes, enhance transparency in the land records maintenance system, and facilitate moving eventually towards guaranteed conclusive titles to immovable properties in the country. One of the major components of the programme is survey/re-survey and updating of all survey and settlement records including creation of original cadastral records wherever necessary. The use of ETS/GPS, Aerial or High Resolution Satellite Images (HRSI) and hybrid method of images are suggested for re-survey in the guidelines. The emerging new satellite technologies enabling earth observation at a spatial resolution of 1.0m or 0.5m or even 0.41m have brought revolutionary changes in the field of cadastral survey. The highresolution satellite imagery (HRSI) is showing its usefulness for cadastral surveys in terms of clear identification of parcel boundaries and other cultural features due to which traditional cadastre and land registration systems have been undergoing major changes worldwide. In the present research study, cadastral maps are derived from ETS/GPS, HRSI of 1.0m and 0.5m and used for comparison. The differences in areas, perimeter and position of parcels derived from HRSI are compared vis-a-vis ETS/GPS boundaries. An assessment has been made on the usefulness of HRSI for re-survey of cadastral maps vis-a-vis conventional ground survey.

  18. The APACHE survey hardware and software design: Tools for an automatic search of small-size transiting exoplanets

    NASA Astrophysics Data System (ADS)

    Christille, Jean-Marc; Bernagozzi, A.; Bertolini, E.; Calcidese, P.; Carbognani, A.; Cenadelli, D.; Damasso, M.; Giacobbe, P.; Lanteri, L.; Lattanzi, M. G.; Sozzetti, A.; Smart, R.

    2013-04-01

    Small-size ground-based telescopes can effectively be used to look for transiting rocky planets around nearby low-mass M stars using the photometric transit method, as recently demonstrated for example by the MEarth project. Since 2008 at the Astronomical Observatory of the Autonomous Region of Aosta Valley (OAVdA), we have been preparing for the long-term photometric survey APACHE, aimed at finding transiting small-size planets around thousands of nearby early and mid-M dwarfs. APACHE (A PAthway toward the Characterization of Habitable Earths) is designed to use an array of five dedicated and identical 40-cm Ritchey-Chretien telescopes and its observations started at the beginning of summer 2012. The main characteristics of the survey final set up and the preliminary results from the first weeks of observations will be discussed.

  19. The Lick-Carnegie Exoplanet Survey: HD 32963—A New Jupiter Analog Orbiting a Sun-like Star

    NASA Astrophysics Data System (ADS)

    Rowan, Dominick; Meschiari, Stefano; Laughlin, Gregory; Vogt, Steven S.; Butler, R. Paul; Burt, Jennifer; Wang, Songhu; Holden, Brad; Hanson, Russell; Arriagada, Pamela; Keiser, Sandy; Teske, Johanna; Diaz, Matias

    2016-02-01

    We present a set of 109 new, high-precision Keck/HIRES radial velocity (RV) observations for the solar-type star HD 32963. Our data set reveals a candidate planetary signal with a period of 6.49 ± 0.07 years and a corresponding minimum mass of 0.7 ± 0.03 Jupiter masses. Given Jupiter's crucial role in shaping the evolution of the early Solar System, we emphasize the importance of long-term RV surveys. Finally, using our complete set of Keck radial velocities and correcting for the relative detectability of synthetic planetary candidates orbiting each of the 1122 stars in our sample, we estimate the frequency of Jupiter analogs across our survey at approximately 3%.

  20. Synthesizing exoplanet demographics from radial velocity and microlensing surveys. II. The frequency of planets orbiting M dwarfs

    SciTech Connect

    Clanton, Christian; Gaudi, B. Scott

    2014-08-20

    In contrast to radial velocity (RV) surveys, results from microlensing surveys indicate that giant planets with masses greater than the critical mass for core accretion (∼0.1 M {sub Jup}) are relatively common around low-mass stars. Using the methodology developed in the first paper, we predict the sensitivity of M-dwarf RV surveys to analogs of the population of planets inferred by microlensing. We find that RV surveys should detect a handful of super-Jovian (>M {sub Jup}) planets at the longest periods being probed. These planets are indeed found by RV surveys, implying that the demographic constraints inferred from these two methods are consistent. Finally, we combine the results from both methods to estimate planet frequencies spanning wide regions of parameter space. We find that the frequency of Jupiters and super-Jupiters (1 ≲ m{sub p} sin i/M {sub Jup} ≲ 13) with periods 1 ≤ P/days ≤ 10{sup 4} is f{sub J}=0.029{sub −0.015}{sup +0.013}, a median factor of 4.3 (1.5-14 at 95% confidence) smaller than the inferred frequency of such planets around FGK stars of 0.11 ± 0.02. However, we find the frequency of all giant planets with 30 ≲ m{sub p} sin i/M {sub ⊕} ≲ 10{sup 4} and 1 ≤ P/days ≤ 10{sup 4} to be f{sub G}=0.15{sub −0.07}{sup +0.06}, only a median factor of 2.2 (0.73-5.9 at 95% confidence) smaller than the inferred frequency of such planets orbiting FGK stars of 0.31 ± 0.07. For a more conservative definition of giant planets (50 ≲ m{sub p} sin i/M {sub ⊕} ≲ 10{sup 4}), we find f{sub G{sup ′}}=0.11±0.05, a median factor of 2.2 (0.73-6.7 at 95% confidence) smaller than that inferred for FGK stars of 0.25 ± 0.05. Finally, we find the frequency of all planets with 1 ≤ m{sub p} sin i/M {sub ⊕} ≤ 10{sup 4} and 1 ≤ P/days ≤ 10{sup 4} to be f{sub p} = 1.9 ± 0.5.

  1. Synthesizing Exoplanet Demographics from Radial Velocity and Microlensing Surveys. II. The Frequency of Planets Orbiting M Dwarfs

    NASA Astrophysics Data System (ADS)

    Clanton, Christian; Gaudi, B. Scott

    2014-08-01

    In contrast to radial velocity (RV) surveys, results from microlensing surveys indicate that giant planets with masses greater than the critical mass for core accretion (~0.1 M Jup) are relatively common around low-mass stars. Using the methodology developed in the first paper, we predict the sensitivity of M-dwarf RV surveys to analogs of the population of planets inferred by microlensing. We find that RV surveys should detect a handful of super-Jovian (>M Jup) planets at the longest periods being probed. These planets are indeed found by RV surveys, implying that the demographic constraints inferred from these two methods are consistent. Finally, we combine the results from both methods to estimate planet frequencies spanning wide regions of parameter space. We find that the frequency of Jupiters and super-Jupiters (1 <~ mp sin i/M Jup <~ 13) with periods 1 <= P/days <= 104 is f_J=0.029^{+0.013}_{-0.015}, a median factor of 4.3 (1.5-14 at 95% confidence) smaller than the inferred frequency of such planets around FGK stars of 0.11 ± 0.02. However, we find the frequency of all giant planets with 30 <~ mp sin i/M ⊕ <~ 104 and 1 <= P/days <= 104 to be f_G=0.15^{+0.06}_{-0.07}, only a median factor of 2.2 (0.73-5.9 at 95% confidence) smaller than the inferred frequency of such planets orbiting FGK stars of 0.31 ± 0.07. For a more conservative definition of giant planets (50 <~ mp sin i/M ⊕ <~ 104), we find f_G^{\\prime }=0.11+/- 0.05, a median factor of 2.2 (0.73-6.7 at 95% confidence) smaller than that inferred for FGK stars of 0.25 ± 0.05. Finally, we find the frequency of all planets with 1 <= mp sin i/M ⊕ <= 104 and 1 <= P/days <= 104 to be fp = 1.9 ± 0.5.

  2. First Temperate Exoplanet Sized Up

    NASA Astrophysics Data System (ADS)

    2010-03-01

    Combining observations from the CoRoT satellite and the ESO HARPS instrument, astronomers have discovered the first "normal" exoplanet that can be studied in great detail. Designated Corot-9b, the planet regularly passes in front of a star similar to the Sun located 1500 light-years away from Earth towards the constellation of Serpens (the Snake). "This is a normal, temperate exoplanet just like dozens we already know, but this is the first whose properties we can study in depth," says Claire Moutou, who is part of the international team of 60 astronomers that made the discovery. "It is bound to become a Rosetta stone in exoplanet research." "Corot-9b is the first exoplanet that really does resemble planets in our solar system," adds lead author Hans Deeg. "It has the size of Jupiter and an orbit similar to that of Mercury." "Like our own giant planets, Jupiter and Saturn, the planet is mostly made of hydrogen and helium," says team member Tristan Guillot, "and it may contain up to 20 Earth masses of other elements, including water and rock at high temperatures and pressures." Corot-9b passes in front of its host star every 95 days, as seen from Earth [1]. This "transit" lasts for about 8 hours, and provides astronomers with much additional information on the planet. This is fortunate as the gas giant shares many features with the majority of exoplanets discovered so far [2]. "Our analysis has provided more information on Corot-9b than for other exoplanets of the same type," says co-author Didier Queloz. "It may open up a new field of research to understand the atmospheres of moderate- and low-temperature planets, and in particular a completely new window in our understanding of low-temperature chemistry." More than 400 exoplanets have been discovered so far, 70 of them through the transit method. Corot-9b is special in that its distance from its host star is about ten times larger than that of any planet previously discovered by this method. And unlike all such

  3. The Near Earth Object Surveillance Satellite (NEOSSat), a Survey Telescope on a Micro-Satellite Platform

    NASA Astrophysics Data System (ADS)

    Laurin, Denis; Hildebrand, A.; Cardinal, R.; Harvey, W.; Tafazoli, S.; Doherty, J.

    2009-01-01

    Although ground-based telescopes have made significant progress in finding near-Earth asteroids (NEA's), marked advantage exist in performing the search from space. The ability to search the ecliptic plane at closer elongations to the Sun, use parallax to discriminate NEA's from those of the Main Belt through distance determinations, and being able to observe continuously are the most significant advantages of a space platform. The Canadian Space Agency (CSA) together with Defense Research and Development Canada (DRDC) are building a micro-satellite platform with a 15 cm telescope dedicated for near space surveillance. The NEOSSat (Near Earth Object Surveillance) spacecraft is expected to be able to detect 20 V magnitude objects with a 100 sec exposure, with a 0.86 deg FOV, on a 1024x1024 CCD, and sub-arcsecond pointing stability. For discovery of NEA's, it will search an area from 45 to 55 degrees solar elongation along the ecliptic plane and ± 40 degrees ecliptic latitude. The observation strategy will be optimized, based upon recent models of the NEA population. Ground-based telescopes will also be used to do follow-ups for orbit determination when possible. The micro-satellite bus and instrument are based on the successful CSA MOST micro-satellite, operating on orbit since 2003. NEOSSat is a shared project with DRDC who will demonstrate the capability of an inexpensive space platform to detect high earth-orbiting satellites and debris (High Earth Orbit Space Surveillance - HEOSS). NEOSSat is base lined for launch in 2010.

  4. QUENCHING OF STAR FORMATION IN SLOAN DIGITAL SKY SURVEY GROUPS: CENTRALS, SATELLITES, AND GALACTIC CONFORMITY

    SciTech Connect

    Knobel, Christian; Lilly, Simon J.; Woo, Joanna; Kovač, Katarina

    2015-02-10

    We re-examine the fraction of low-redshift Sloan Digital Sky Survey satellites and centrals in which star formation has been quenched, using the environment quenching efficiency formalism that separates out the dependence of stellar mass. We show that the centrals of the groups containing the satellites are responding to the environment in the same way as their satellites (at least for stellar masses above 10{sup 10.3} M {sub ☉}), and that the well-known differences between satellites and the general set of centrals arise because the latter are overwhelmingly dominated by isolated galaxies. The widespread concept of ''satellite quenching'' as the cause of environmental effects in the galaxy population can therefore be generalized to ''group quenching''. We then explore the dependence of the quenching efficiency of satellites on overdensity, group-centric distance, halo mass, the stellar mass of the satellite, and the stellar mass and specific star formation rate (sSFR) of its central, trying to isolate the effect of these often interdependent variables. We emphasize the importance of the central sSFR in the quenching efficiency of the associated satellites, and develop the meaning of this ''galactic conformity'' effect in a probabilistic description of the quenching of galaxies. We show that conformity is strong, and that it varies strongly across parameter space. Several arguments then suggest that environmental quenching and mass quenching may be different manifestations of the same underlying process. The marked difference in the apparent mass dependencies of environment quenching and mass quenching which produces distinctive signatures in the mass functions of centrals and satellites will arise naturally, since, for satellites at least, the distributions of the environmental variables that we investigate in this work are essentially independent of the stellar mass of the satellite.

  5. The Lick-Carnegie exoplanet survey: Gliese 687 b—A Neptune-mass planet orbiting a nearby red dwarf

    SciTech Connect

    Burt, Jennifer; Vogt, Steven S.; Hanson, Russell; Rivera, Eugenio J.; Laughlin, Gregory; Meschiari, Stefano; Henry, Gregory W.

    2014-07-10

    Precision radial velocities from the Automated Planet Finder (APF) and Keck/HIRES reveal an Msin (i) = 18 ± 2 M{sub ⊕} planet orbiting the nearby M3V star GJ 687. This planet has an orbital period P = 38.14 days and a low orbital eccentricity. Our Strömgren b and y photometry of the host star suggests a stellar rotation signature with a period of P = 60 days. The star is somewhat chromospherically active, with a spot filling factor estimated to be several percent. The rotationally induced 60 day signal, however, is well separated from the period of the radial velocity variations, instilling confidence in the interpretation of a Keplerian origin for the observed velocity variations. Although GJ 687 b produces relatively little specific interest in connection with its individual properties, a compelling case can be argued that it is worthy of remark as an eminently typical, yet at a distance of 4.52 pc, a very nearby representative of the galactic planetary census. The detection of GJ 687 b indicates that the APF telescope is well suited to the discovery of low-mass planets orbiting low-mass stars in the as yet relatively un-surveyed region of the sky near the north celestial pole.

  6. Satellite Detection in AdvancedCamera for Surveys/Wide Field Channel Images

    NASA Astrophysics Data System (ADS)

    Borncamp, D.; Lim, Pey-Lian

    2016-01-01

    This document explains the process by which satellite trails can be found within individual chips of an Advanced Camera for Surveys (ACS) Wide Field Channel (WFC) image. Since satellites are transient and sporadic events, we used the Hubble Frontier Fields (HFF) dataset which is manually checked for satellite trails has been used as a truth set to verify that the method in this document does a complete job without a high false positive rate. This document also details the process of producing a mask that will update data quality information to inform users where the trail traverses the image and properly account for the affected pixels. Along with this document, the Python source code used to detect and mask satellite trails will be released to users with as a stand-alone product within the STSDAS acstools package.

  7. Hubble Exoplanet Pro/Am Collaboration (Abstract)

    NASA Astrophysics Data System (ADS)

    Conti, D. M.

    2016-06-01

    (Abstract only) A collaborative effort is being organized between a world-wide network of amateur astronomers and a Hubble Space Telescope (HST) science team. The purpose of this collaboration is to supplement an HST near-infrared spectroscopy survey of some 15 exoplanets with ground-based observations in the visible range.

  8. THE LICK-CARNEGIE EXOPLANET SURVEY: A URANUS-MASS FOURTH PLANET FOR GJ 876 IN AN EXTRASOLAR LAPLACE CONFIGURATION

    SciTech Connect

    Rivera, Eugenio J.; Laughlin, Gregory; Vogt, Steven S.; Meschiari, Stefano; Haghighipour, Nader

    2010-08-10

    billion years (at least for the coplanar cases). This resonant configuration of three giant planets orbiting an M dwarf primary differs from the well-known Laplace configuration of the three inner Galilean satellites of Jupiter, which are executing very small librations about {psi}{sub Laplace} = 180{sup 0} and which never experience triple conjunctions. The GJ 876 system, by contrast, comes close to a triple conjunction between the outer three planets once per every orbit of the outer planet, 'e'.

  9. A multifaceted approach to understanding dynamic urban processes: satellites, surveys, and censuses.

    NASA Astrophysics Data System (ADS)

    Jones, B.; Balk, D.; Montgomery, M.; Liu, Z.

    2014-12-01

    Urbanization will arguably be the most significant demographic trend of the 21st century, particularly in fast-growing regions of the developing world. Characterizing urbanization in a spatial context, however, is a difficult task given only the moderate resolution data provided by traditional sources of demographic data (i.e., censuses and surveys). Using a sample of five world "mega-cities" we demonstrate how new satellite data products and new analysis of existing satellite data, when combined with new applications of census and survey microdata, can reveal more about cities and urbanization in combination than either data type can by itself. In addition to the partially modelled Global Urban-Rural Mapping Project (GRUMP) urban extents we consider four sources of remotely sensed data that can be used to estimate urban extents; the NOAA Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) intercallibrated nighttime lights time series data, the newer NOAA Visible Infrared Imager Radiometer Suite (VIIRS) nighttime lights data, the German Aerospace Center (DLR) radar satellite data, and Dense Sampling Method (DSM) analysis of the NASA scatterometer data. Demographic data come from national censuses and/or georeferenced survey data from the Demographic & Health Survey (DHS) program. We overlay demographic and remotely sensed data (e.g., Figs 1, 2) to address two questions; (1) how well do satellite derived measures of urban intensity correlate with demographic measures, and (2) how well are temporal changes in the data correlated. Using spatial regression techniques, we then estimate statistical relationships (controlling for influences such as elevation, coastal proximity, and economic development) between the remotely sensed and demographic data and test the ability of each to predict the other. Satellite derived imagery help us to better understand the evolution of the built environment and urban form, while the underlying demographic

  10. Surveys of the earth's resources and environment by satellites

    NASA Technical Reports Server (NTRS)

    Nordberg, W.; Tiedemann, H.; Bohn, C.

    1975-01-01

    The potential and promise of observing the earth from the vantage point of space is discussed. The systematic surveying of processes and phenomena occurring on the surface of the earth by Landsat 1 and Nimbus 5 is considered to be useful in the following areas: assessment of water resources; mineral and petroleum exploration; land use planning; crop, forest, and rangeland inventory; assessment of flood, earthquake, and other environmental hazards; monitoring coastal processes; environmental effects of industrial effluents and of air pollution; mapping the distribution and types of ice covering the earth's polar caps and global soil moisture distributions.

  11. A satellite geodetic survey of spatiotemporal deformation of Iranian volcanos

    NASA Astrophysics Data System (ADS)

    Shirzaei, M.

    2012-04-01

    Surface deformation in volcanic areas is usually due to movement of magma, hydrothermal activity at depth, weight of volcano, landside, etc. Iran, located at the convergence of the Eurasian and Arabian tectonic plates, is the host of five apparently inactive volcanoes, named 'Damavand', 'Taftan', 'Bazman', 'Sabalan' and 'Sahand'. Through investigation of the long term surface deformation rate at Damavand volcano, the highest point in the middle east, Shirzaei et al. (2011) demonstrated that a slow gravity-driven deformation in the form of spreading is going on at this volcano. Extending the earlier work, in this study, I explore large sets of SAR data obtained by Envisat radar satellite from 2003 through 2010 at all Iranian volcanoes. Multitemporal interferometric analysis of the SAR data sets allows retrieving sub-millimeter surface deformation at these volcanic systems. As a result, I detect a transient flank failure in the form of landslide at Damavand that is followed by elevated fumarolic activity. This suggests that landslide might have triggered volcanic unrest. Moreover, I measure significant surface deformation at Taftan and Bazman volcanos associated with different episodes of uplift and subsidence. The inverse model simulations suggest that the time-dependent inflations and deflations of extended and spherical pressurized magma chambers are responsible for the surface displacements at these volcanoes. I also detect time-dependent surface displacements at Sabalan and Sahand volcanoes, where the investigation of the type and the sources of the observed deformation is subject of ongoing research. This study is a best example that shows the absent of recent eruption can not be used as a reliable factor in volcanic hazard assessment and a continuous monitoring system is of vital importance. Reference Shirzaei, M., Walter, T.R., Nankali, H.R. and Holohan, E.P., 2011. Gravity-driven deformation of Damavand volcano, Iran, detected through InSAR time series

  12. The NASA Exoplanet Archive: Data Inventory Service

    NASA Astrophysics Data System (ADS)

    Ramirez, Solange; Akeson, Rachel L.; Ciardi, David R.; Chen, Xi; Christiansen, Jessie; Plavchan, Peter

    2014-06-01

    We present here the latest addition to the NASA Exoplanet Archive - the Data Inventory Service, a tool aimed to provide the user with all the data available within the archive (exoplanet and stellar parameters, time series from ground-based transit surveys (such as Super WASP, XO, HAT-P, KELT), Kepler Pipeline products, CoRoT light curves, etc.) at or near the location of an astronomical object. The NASA Exoplanet Archive is an online service dedicated to compile and to serve public astronomical data sets involved in the search for and characterization of extrasolar planets and their host stars. The data in the archive include stellar parameters (e.g., positions, magnitudes, temperatures, etc.), exoplanet parameters (such as masses and orbital parameters) and discovery/characterization data (e.g., published radial velocity curves, photometric light curves, spectra, etc.). In support of the Kepler Extended Mission, the NASA Exoplanet Archive also hosts data related to Kepler Objects of Interest (KOI), Kepler Pipeline products such as Threshold Crossing Events (TCE) and Data Validation Reports, and Kepler Stellar parameters as used by the Kepler Pipeline. The archive provides tools to work with these data, including interative tables (with plotting capabilities), interactive light curve viewer, periodogram service, transit and ephemeris calculator, and application program interface. To access this information visit us at: http://exoplanetarchive.ipac.caltech.edu

  13. Direct imaging of exoplanets.

    PubMed

    Lagrange, Anne-Marie

    2014-04-28

    Most of the exoplanets known today have been discovered by indirect techniques, based on the study of the host star radial velocity or photometric temporal variations. These detections allowed the study of the planet populations in the first 5-8 AU from the central stars and have provided precious information on the way planets form and evolve at such separations. Direct imaging on 8-10 m class telescopes allows the detection of giant planets at larger separations (currently typically more than 5-10 AU) complementing the indirect techniques. So far, only a few planets have been imaged around young stars, but each of them provides an opportunity for unique dedicated studies of their orbital, physical and atmospheric properties and sometimes also on the interaction with the 'second-generation', debris discs. These few detections already challenge formation theories. In this paper, I present the results of direct imaging surveys obtained so far, and what they already tell us about giant planet (GP) formation and evolution. Individual and emblematic cases are detailed; they illustrate what future instruments will routinely deliver for a much larger number of stars. I also point out the limitations of this approach, as well as the needs for further work in terms of planet formation modelling. I finally present the progress expected in direct imaging in the near future, thanks in particular to forthcoming planet imagers on 8-10 m class telescopes. PMID:24664924

  14. Statistical properties of exoplanets

    NASA Astrophysics Data System (ADS)

    Udry, Stéphane

    Since the detection a decade ago of the planetary companion of 51 Peg, more than 165 extrasolar planets have been unveiled by radial-velocity measurements. They present a wide variety of characteristics such as large masses with small orbital separations, high eccentricities, period resonances in multi-planet systems, etc. Meaningful features of the statistical distributions of the orbital parameters or parent stellar properties have emerged. We discuss them in the context of the constraints they provide for planet-formation models and in comparison to Neptune-mass planets in short-period orbits recently detected by radial-velocity surveys, thanks to new instrumental developments and adequate observing strategy. We expect continued improvement in velocity precision and anticipate the detection of Neptune-mass planets in longer-period orbits and even lower-mass planets in short-period orbits, giving us new information on the mass distribution function of exoplanets. Finally, the role of radial-velocity follow-up measurements of transit candidates is emphasized.

  15. LEECH: LBTI Exozodi Exoplanet Common Hunt

    NASA Astrophysics Data System (ADS)

    Skemer, A.

    2014-03-01

    In Spring 2013, the LEECH (LBTI Exozodi Exoplanet Common Hunt) survey began its 100-night campaign from the Large Binocular Telescope (LBT) atop Mt Graham, Arizona. This survey benefits from the many technological achievements of the LBT, including two 8.4- meter mirrors on a single fixed mount, dual adaptive secondary mirrors for high Strehl performance, and a cold beam combiner to dramatically reducing the telescope's overall background emissivity. LEECH neatly complements other high-contrast planet imaging efforts by observing stars at L' (3.8 microns) with LMIRcam, as opposed to the shorter wavelength near-infrared bands (1-2.4 microns) of other similar surveys. This portion of the spectrum offers deeper mass sensitivity for intermediate age (several hundred Myr-old) systems, since their Jovian-mass planets radiate predominantly in the mid-infrared. The goals of LEECH are to (1) discover new exoplanets, (2) characterize the atmospheres of newly discovered exoplanets, (3) characterize the architectures of nearby planetary systems, and (4) establish meaningful constraints on the prevalence of wideseparation exoplanets.

  16. PROPERTIES OF SATELLITE GALAXIES IN THE SDSS PHOTOMETRIC SURVEY: LUMINOSITIES, COLORS, AND PROJECTED NUMBER DENSITY PROFILES

    SciTech Connect

    Lares, M.; Lambas, D. G.; Dominguez, M. J.

    2011-07-15

    We analyze photometric data in the Sloan Digital Sky Survey Data Release 7 (SDSS-DR7) to infer statistical properties of faint satellites associated with isolated bright galaxies (M{sub r} < -20.5) in the redshift range 0.03 < z < 0.1. The mean projected radial number density profile shows an excess of companions in the photometric sample around the primaries, with approximately a power-law shape that extends up to {approx_equal} 700 kpc. Given this overdensity signal, a suitable background subtraction method is used to study the statistical properties of the population of bound satellites, down to magnitude M{sub r} = -14.5, in the projected radial distance range 100 < r{sub p} /kpc < 3(R{sub vir}). The maximum projected distance corresponds to the range 470-660 kpc for the different samples. We have also considered a color cut consistent with the observed colors of spectroscopic satellites in nearby galaxies so that distant redshifted galaxies do not dominate the statistics. We have tested the implementation of this background subtraction procedure using a mock catalog derived from the Millennium simulation semianalytic galaxy catalog based on a {Lambda} cold dark matter model. We find that the method is effective in reproducing the true projected radial satellite number density profile and luminosity distributions, providing confidence in the results derived from SDSS data. We find that the spatial extent of satellite systems is larger for bright, red primaries. Also, we find a larger spatial distribution of blue satellites. For the different samples analyzed, we derive the average number of satellites and their luminosity distributions down to M{sub r} = -14.5. The mean number of satellites depends very strongly on host luminosity. Bright primaries (M{sub r} < -21.5) host on average {approx}6 satellites with M{sub r} < -14.5. This number is reduced for primaries with lower luminosities (-21.5 < M{sub r} < -20.5) which have less than one satellite per host. We

  17. The NASA Exoplanet Archive

    NASA Astrophysics Data System (ADS)

    Ramirez, Solange; Akeson, R. L.; Ciardi, D.; Kane, S. R.; Plavchan, P.; von Braun, K.; NASA Exoplanet Archive Team

    2013-01-01

    The NASA Exoplanet Archive is an online service that compiles and correlates astronomical information on extra solar planets and their host stars. The data in the archive include exoplanet parameters (such as orbits, masses, and radii), associated data (such as published radial velocity curves, photometric light curves, images, and spectra), and stellar parameters (such as magnitudes, positions, and temperatures). All the archived data are linked to the original literature reference.The archive provides tools to work with these data, including interactive tables (with plotting capabilities), interactive light curve viewer, periodogram service, transit and ephemeris calculator, and application program interface.The NASA Exoplanet Archive is the U.S. portal to the public CoRoT mission data for both the Exoplanet and Asteroseismology data sets. The NASA Exoplanet Archive also serves data related to Kepler Objects of Interest (Planet Candidates and the Kepler False Positives, KOI) in an integrated and interactive table containing stellar and transit parameters. In support of the Kepler Extended Mission, the NASA Exoplanet Archive will host transit modeling parameters, centroid results, several statistical values, and summary and detailed reports for all transit-like events identified by the Kepler Pipeline. To access this information visit us at: http://exoplanetarchive.ipac.caltech.edu

  18. Exoplanet Community Report on Direct Infrared Imaging of Exoplanets

    NASA Technical Reports Server (NTRS)

    Danchi, William C.; Lawson, Peter R.

    2009-01-01

    Direct infrared imaging and spectroscopy of exoplanets will allow for detailed characterization of the atmospheric constituents of more than 200 nearby Earth-like planets, more than is possible with any other method under consideration. A flagship mission based on larger passively cooled infrared telescopes and formation flying technologies would have the highest angular resolution of any concept under consideration. The 2008 Exoplanet Forum committee on Direct Infrared Imaging of Exoplanets recommends: (1) a vigorous technology program including component development, integrated testbeds, and end-to-end modeling in the areas of formation flying and mid-infrared nulling; (2) a probe-scale mission based on a passively cooled structurally connected interferometer to be started within the next two to five years, for exoplanetary system characterization that is not accessible from the ground, and which would provide transformative science and lay the engineering groundwork for the flagship mission with formation flying elements. Such a mission would enable a complete exozodiacal dust survey (<1 solar system zodi) in the habitable zone of all nearby stars. This information will allow for a more efficient strategy of spectral characterization of Earth-sized planets for the flagship missions, and also will allow for optimization of the search strategy of an astrometric mission if such a mission were delayed due to cost or technology reasons. (3) Both the flagship and probe missions should be pursued with international partners if possible. Fruitful collaboration with international partners on mission concepts and relevant technology should be continued. (4) Research and Analysis (R&A) should be supported for the development of preliminary science and mission designs. Ongoing efforts to characterize the the typical level of exozodiacal light around Sun-like stars with ground-based nulling technology should be continued.

  19. THE DISTRIBUTION OF FAINT SATELLITES AROUND CENTRAL GALAXIES IN THE CANADA-FRANCE-HAWAII TELESCOPE LEGACY SURVEY

    SciTech Connect

    Jiang, C. Y.; Jing, Y. P.; Li, Cheng

    2012-11-20

    We investigate the radial number density profile and the abundance distribution of faint satellites around central galaxies in the low-redshift universe using the Canada-France-Hawaii Telescope (CFHT) Legacy Survey. We consider three samples of central galaxies with magnitudes of M {sub r} = -21, -22, and -23 selected from the Sloan Digital Sky Survey group catalog of Yang et al. The satellite distribution around these central galaxies is obtained by cross-correlating these galaxies with the photometric catalog of the CFHT Legacy Survey. The projected radial number density of the satellites obeys a power-law form with the best-fit logarithmic slope of -1.05, independent of both the central galaxy luminosity and the satellite luminosity. The projected cross-correlation function between central and satellite galaxies exhibits a non-monotonic trend with satellite luminosity. It is most pronounced for central galaxies with M {sub r} = -21, where the decreasing trend of clustering amplitude with satellite luminosity is reversed when satellites are fainter than central galaxies by more than 2 mag. A comparison with the satellite luminosity functions in the Milky Way (MW) and M31 shows that the MW/M31 system has about twice as many satellites as around a typical central galaxy of similar luminosity. The implications for theoretical models are briefly discussed.

  20. Continuing evolution of satellite-based geodetic positioning and survey navigation capabilities

    SciTech Connect

    Stansell, T.A. Jr.

    1981-01-01

    The paper reviews progress in the TRANSIT Navigation Satellite System for Offshore oil exploration and land geodetic survey, and examines trends affecting future developments. This report covers three major areas. The first is the field of land geodetic survey. The second area focuses on the evolution of integrated navigation systems for offshore oil exploration. The objective is to show how these systems have matured. Trends affecting the direction of future developments are discussed. Finally, this paper evaluates the coming impact of NAVSTAR, the Global Positioning System. 14 refs.

  1. Survey of Verification and Validation Techniques for Small Satellite Software Development

    NASA Technical Reports Server (NTRS)

    Jacklin, Stephen A.

    2015-01-01

    The purpose of this paper is to provide an overview of the current trends and practices in small-satellite software verification and validation. This document is not intended to promote a specific software assurance method. Rather, it seeks to present an unbiased survey of software assurance methods used to verify and validate small satellite software and to make mention of the benefits and value of each approach. These methods include simulation and testing, verification and validation with model-based design, formal methods, and fault-tolerant software design with run-time monitoring. Although the literature reveals that simulation and testing has by far the longest legacy, model-based design methods are proving to be useful for software verification and validation. Some work in formal methods, though not widely used for any satellites, may offer new ways to improve small satellite software verification and validation. These methods need to be further advanced to deal with the state explosion problem and to make them more usable by small-satellite software engineers to be regularly applied to software verification. Last, it is explained how run-time monitoring, combined with fault-tolerant software design methods, provides an important means to detect and correct software errors that escape the verification process or those errors that are produced after launch through the effects of ionizing radiation.

  2. The history of exoplanet detection.

    PubMed

    Perryman, Michael

    2012-10-01

    I summarize the early developments of the more quantitative aspects of exoplanet detection. After a brief overview of the observational methods currently applied to exoplanet searches and a summary of the first true exoplanet detections resulting from these various techniques, the more relevant historical background is organized according to the observational techniques that are currently most relevant. PMID:23013272

  3. Asteroseismology of Exoplanet-Host Stars in the TESS Era

    NASA Astrophysics Data System (ADS)

    Campante, Tiago L.; Schofield, Mathew; Chaplin, William J.; Huber, Daniel; Christensen-Dalsgaard, Jørgen; Kjeldsen, Hans; Latham, David W.; Ricker, George R.; Winn, Joshua

    2015-12-01

    New insights on stellar evolution and stellar interiors physics are being made possible by asteroseismology, the study of stars by the observation of their natural, resonant oscillations. Throughout the duration of the Kepler mission, asteroseismology has also played an important role in the characterization of host stars and their planetary systems. Examples include the precise estimation of the fundamental properties of stellar hosts, the obliquity determination of planetary systems, or the orbital eccentricity determination via asterodensity profiling. The Transiting Exoplanet Survey Satellite (TESS) will perform a wide-field survey for planets that transit bright host stars. Its excellent photometric precision and long intervals of uninterrupted observations will enable asteroseismology of solar-type stars and their evolved counterparts. Based on existing all-sky simulations of the stellar and planetary populations, we investigate the asteroseismic yield of the mission, placing particular emphasis on the yield of exoplanet-host stars for which we expect to detect solar-like oscillations. This is done both for the cohort of target stars (observed at a 2-min cadence), which will mainly involve low-mass main-sequence hosts, as well as for the cohort of “full-frame image” stars (observed at a 30-min cadence). The latter cohort offers the exciting prospect of conducting asteroseismology on a significant number of evolved hosts. Also, the brightest solar-type hosts with asteroseismology will become some of the best characterized planetary systems known to date. Finally, we discuss the impact of the detected oscillations on the accuracy/precision of the derived properties of the host stars and their planetary systems.

  4. Selection of Nearby Star Targets for the Subaru Strategic Exploration of Exoplanets and Disks

    NASA Astrophysics Data System (ADS)

    Kandori, R.; Tamura, M.; Morino, J.; Ishii, M.; Suzuki, R.; Hashimoto, J.; Kusakabe, N.; Narita, N.; Sato, B.; Yamada, T.; Enya, K.; Goto, M.; Carson, J.; Thalmann, C.; McElwain, M.; Moro-Martin, A.; Knapp, J.; Turner, E. L.

    2009-08-01

    SEEDS (the Subaru Strategic Exploration of Exoplanets and Disks with Hi-CIAO/AO188) is a strategic five-year campaign of direct imaging surveys of exoplanets/disks using the Subaru telescope equipped with the new adaptive optics system AO188 and our new high-contrast instrument, HiCIAO. The goals of the survey are to address the following key issues in exoplanet/disk sciences: (1) the detection and census of exoplanets; (2) the evolution of protoplanetary and debris disks; and (3) the link between exoplanets and disks. Targets prepared for the SEEDS exoplanet searches are in four categories, including nearby stars. We present our scientific motivations and current status of the SEEDS target selection in the nearby stars category.

  5. Asteroseismology and Exoplanet Hosts

    NASA Astrophysics Data System (ADS)

    Huber, Daniel

    2015-08-01

    Asteroseismology is among the most powerful observational tools to determine fundamental properties of stars. Space-based photometry has recently enabled the systematic detection of oscillations in exoplanet host stars, allowing a combination of asteroseismology with transit and radial-velocity measurements to precisely characterize planetary systems. In this talk I will review the latest asteroseismic detections in exoplanet host stars spanning from the main sequence to the red-giant branch, focusing in particular on radii and ages of stars hosting small (sub-Neptune sized) planets discovered by the Kepler mission. I will furthermore discuss applications of asteroseismology to measure spin-orbit inclinations in multiplanet systems, and their implications for formation theories of hot Jupiters. Finally I will give an outlook on asteroseismic studies of exoplanet hosts with current and future space- and ground-based facilities such as K2, SONG, TESS, and PLATO.

  6. KELT-10b: The First Transiting Exoplanet from the KELT-South Survey - A Hot Sub-Jupiter Transiting a V=10.7 Early G-Star

    NASA Astrophysics Data System (ADS)

    Kuhn, Rudolf B.; Rodriguez, Joseph E.; Collins, Karen A.; Lund, Michael B.; Siverd, Robert J.; Colón, Knicole D.; Pepper, Joshua; Stassun, Keivan G.; Cargile, Phillip A.; James, David J.; Penev, Kaloyan; Zhou, George; Bayliss, Daniel; Tan, T. G.; Curtis, Ivan A.; Udry, Stephane; Segransan, Damien; Mawet, Dimitri; Dhital, Saurav; Soutter, Jack; Hart, Rhodes; Carter, Brad; Gaudi, B. Scott; Myers, Gordon; Beatty, Thomas G.; Eastman, Jason D.; Reichart, Daniel E.; Haislip, Joshua B.; Kielkopf, John; Bieryla, Allyson; Latham, David W.; Jensen, Eric L. N.; Oberst, Thomas E.; Stevens, Daniel J.

    2016-04-01

    We report the discovery of KELT-10b, the first transiting exoplanet discovered using the KELT-South telescope. KELT-10b is a highly inflated sub-Jupiter mass planet transiting a relatively bright V = 10.7 star (TYC 8378-64-1), with Teff = 5948 ± 74 K, log g = 4.319_{-0.030}^{+0.020} and [Fe/H] = 0.09_{-0.10}^{+0.11}, an inferred mass M★ = 1.112_{-0.061}^{+0.055} M⊙ and radius R★ = 1.209_{-0.035}^{+0.047} R⊙. The planet has a radius Rp = 1.399_{-0.049}^{+0.069} RJ and mass Mp = 0.679_{-0.038}^{+0.039} MJ. The planet has an eccentricity consistent with zero and a semi-major axis a = 0.05250_{-0.00097}^{+0.00086} AU. The best fitting linear ephemeris is T0 = 2457066.72045±0.00027 BJDTDB and P = 4.1662739±0.0000063 days. This planet joins a group of highly inflated transiting exoplanets with a radius larger and a mass less than that of Jupiter. The planet, which boasts deep transits of 1.4%, has a relatively high equilibrium temperature of Teq = 1377_{-23}^{+28} K, assuming zero albedo and perfect heat redistribution. KELT-10b receives an estimated insolation of 0.817_{-0.054}^{+0.068} × 109 erg s-1 cm-2, which places it far above the insolation threshold above which hot Jupiters exhibit increasing amounts of radius inflation. Evolutionary analysis of the host star suggests that KELT-10b may not survive beyond the current subgiant phase, depending on the rate of in-spiral of the planet over the next few Gyr. The planet transits a relatively bright star and exhibits the third largest transit depth of all transiting exoplanets with V < 11 in the southern hemisphere, making it a promising candidate for future atmospheric characterization studies.

  7. Further evidence for historical decline of Antarctic sea ice prior to satellite survey era?

    NASA Astrophysics Data System (ADS)

    Gersonde, Rainer; Esper, Oliver; Lohmann, Gerrit; Knorr, Gregor

    2013-04-01

    The decline in Arctic summer sea ice which accelerated during the present century to reach a yet unequaled minimum extent in 2012 as monitored by the satellite-based sea ice survey since the late 1970s is thought to represent one of the most striking examples of current climate change related to the anthropogenic global warming. In contrast, Antarctic sea ice extent has remained nearly unchanged during the past 40 years, according to the satellite survey. The statistical analysis of microfossil (diatom) signals indicative of sea ice occurrence retrieved from a large set of surface samples covering the Pacific, Atlantic and the eastern Indian sectors of the Southern Ocean suggests that Antarctic winter sea ice extent was more extended than the sea ice field documented by satellite surveys. The surface samples generally integrate signals deposited over 100-200 years. Most substantial offsets between the sedimentary proxy and satellite derived data on sea ice extent were encountered on latitudinal transects across the Pacific sector. Independent support for a 20th century decline of Antarctic sea ice fields by up to 25% prior to satellite survey comes from the analysis of whaling positions [1, 2], ice core proxies [3] and combinations of observations with numerical modeling [4]. Proxy records from Holocene sediment cores allow for further extension of sea ice records beyond the short instrumental record. These records indicate that the more extended Antarctic winter sea ice derived from the surface sediment record is a common feature in the present interglacial (Holocene) period, except for the earliest Holocene when the sea ice field was even smaller than present. The proxy results are suitable for validation of reanalysis and numerical model data and will allow for a better understanding of Antarctic sea ice sensitivity in response to natural and anthropogenic processes. [1] de la Mare, W. K. 2009. Clim. Change 92,461-493; [2] Cotté, C., Guinet, C. 2007. Deep

  8. ExELS: an exoplanet legacy science proposal for the ESA Euclid mission - I. Cold exoplanets

    NASA Astrophysics Data System (ADS)

    Penny, M. T.; Kerins, E.; Rattenbury, N.; Beaulieu, J.-P.; Robin, A. C.; Mao, S.; Batista, V.; Calchi Novati, S.; Cassan, A.; Fouqué, P.; McDonald, I.; Marquette, J. B.; Tisserand, P.; Zapatero Osorio, M. R.

    2013-09-01

    The Euclid mission is the second M-class mission of the ESA Cosmic Vision programme, with the principal science goal of studying dark energy through observations of weak lensing and baryon acoustic oscillations. Euclid is also expected to undertake additional Legacy Science programmes. One such proposal is the Exoplanet Euclid Legacy Survey (ExELS) which will be the first survey able to measure the abundance of exoplanets down to Earth mass for host separations from ˜1 au out to the free-floating (unbound) regime. The cold and free-floating exoplanet regimes represent a crucial discovery space for testing planet formation theories. ExELS will use the gravitational microlensing technique and will detect 1000 microlensing events per month over 1.6 deg2 of the Galactic bulge. We assess how many of these events will have detectable planetary signatures using a detailed multiwavelength microlensing simulator - the Manchester-Besançon microLensing Simulator (MABμLS) - which incorporates the Besançon Galactic model with 3D extinction. MABμLS is the first theoretical simulation of microlensing to treat the effects of point spread function (PSF) blending self-consistently with the underlying Galactic model. We use MABμLS, together with current numerical models for the Euclid PSFs, to explore a number of designs and de-scope options for ExELS, including the exoplanet yield as a function of filter choice and slewing time, and the effect of systematic photometry errors. Using conservative extrapolations of current empirical exoplanet mass functions determined from ground-based microlensing and radial velocity surveys, ExELS can expect to detect a few hundred cold exoplanets around mainly G-, K- and M-type stellar hosts, including ˜45 Earth-mass planets and ˜6 Mars-mass planets for an observing programme totalling 10 months. ExELS will be capable of measuring the cold exoplanet mass function down to Earth mass or below, with orbital separations ranging from ˜1 au out

  9. The gas-phase metallicity of central and satellite galaxies in the Sloan Digital Sky Survey

    NASA Astrophysics Data System (ADS)

    Pasquali, Anna; Gallazzi, Anna; van den Bosch, Frank C.

    2012-09-01

    We exploit the galaxy groups catalogue of Yang et al. and the galaxy properties measured in the Sloan Digital Sky Survey Data Releases 4 and 7 to study how the gas-phase metallicities of star-forming galaxies depend on environment. We find that satellite and central galaxies follow a qualitatively similar stellar mass (M★)-gas-phase metallicity relation, whereby their gas-phase metallicity increases with M★. Satellites, though, have higher gas-phase metallicities than equally massive centrals, and this difference increases with decreasing stellar mass. We find a maximum offset of 0.06 dex at log(M★/h-2 M⊙) ≃ 8.25. At fixed halo mass, centrals are more metal rich than satellites by ˜0.5 dex on average. This is simply due to the fact that, by definition, centrals are the most massive galaxies in their groups, and the fact that gas-phase metallicity increases with stellar mass. More interestingly, we also find that the gas-phase metallicity of satellites increases with halo mass (Mh) at fixed stellar mass. This increment is more pronounced for less massive galaxies, and, at M★ ≃ 109 h-2 M⊙, corresponds to ˜0.15 dex across the range 11 < log (Mh/h-1 M⊙) < 14. We also show that low-mass satellite galaxies have higher gas-phase metallicities than central galaxies of the same stellar metallicity. This difference becomes negligible for more massive galaxies of roughly solar metallicity. We demonstrate that the observed differences in gas-phase metallicity between centrals and satellites at fixed M★ are not a consequence of stellar mass stripping (advocated by Pasquali et al. in order to explain similar differences but in stellar metallicity), nor to the past star formation history of these galaxies as quantified by their surface mass density or gas mass fraction. Rather, we argue that these trends probably originate from a combination of three environmental effects: (i) strangulation, which prevents satellite galaxies from accreting new, low

  10. The Phase Curve Survey of the Irregular Saturnian Satellites: A Possible Method of Physical Classification

    NASA Technical Reports Server (NTRS)

    Bauer, James M.; Grav, Tommy; Buratti, Bonnie J.; Hicks, Michael D.

    2006-01-01

    During its 2005 January opposition, the saturnian system could be viewed at an unusually low phase angle. We surveyed a subset of Saturn's irregular satellites to obtain their true opposition magnitudes, or nearly so, down to phase angle values of 0.01 deg. Combining our data taken at the Palomar 200-inch and Cerro Tololo Inter-American Observatory's 4-m Blanco telescope with those in the literature, we present the first phase curves for nearly half the irregular satellites originally reported by Gladman et al. [2001. Nature 412, 163-166], including Paaliaq (SXX), Siarnaq (SXXIX), Tarvos (SXXI), Ijiraq (SXXII), Albiorix (SXVI), and additionally Phoebe's narrowest angle brightness measured to date. We find centaur-like steepness in the phase curves or opposition surges in most cases with the notable exception of three, Albiorix and Tarvos, which are suspected to be of similar origin based on dynamical arguments, and Siarnaq.During its 2005 January opposition, the saturnian system could be viewed at an unusually low phase angle. We surveyed a subset of Saturn's irregular satellites to obtain their true opposition magnitudes, or nearly so, down to phase angle values of 0.01 deg. Combining our data taken at the Palomar 200-inch and Cerro Tololo Inter-American Observatory's 4-m Blanco telescope with those in the literature, we present the first phase curves for nearly half the irregular satellites originally reported by Gladman et al. [2001. Nature 412, 163-166], including Paaliaq (SXX), Siarnaq (SXXIX), Tarvos (SXXI), Ijiraq (SXXII), Albiorix (SXVI), and additionally Phoebe's narrowest angle brightness measured to date. We find centaur-like steepness in the phase curves or opposition surges in most cases with the notable exception of three, Albiorix and Tarvos, which are suspected to be of similar origin based on dynamical arguments, and Siarnaq.

  11. Begomovirus-Associated Satellite DNA Diversity Captured Through Vector-Enabled Metagenomic (VEM) Surveys Using Whiteflies (Aleyrodidae).

    PubMed

    Rosario, Karyna; Marr, Christian; Varsani, Arvind; Kraberger, Simona; Stainton, Daisy; Moriones, Enrique; Polston, Jane E; Breitbart, Mya

    2016-02-01

    Monopartite begomoviruses (Geminiviridae), which are whitefly-transmitted single-stranded DNA viruses known for causing devastating crop diseases, are often associated with satellite DNAs. Since begomovirus acquisition or exchange of satellite DNAs may lead to adaptation to new plant hosts and emergence of new disease complexes, it is important to investigate the diversity and distribution of these molecules. This study reports begomovirus-associated satellite DNAs identified during a vector-enabled metagenomic (VEM) survey of begomoviruses using whiteflies collected in various locations (California (USA), Guatemala, Israel, Puerto Rico, and Spain). Protein-encoding satellite DNAs, including alphasatellites and betasatellites, were identified in Israel, Puerto Rico, and Guatemala. Novel alphasatellites were detected in samples from Guatemala and Puerto Rico, resulting in the description of a phylogenetic clade (DNA-3-type alphasatellites) dominated by New World sequences. In addition, a diversity of small (~640-750 nucleotides) satellite DNAs similar to satellites associated with begomoviruses infecting Ipomoea spp. were detected in Puerto Rico and Spain. A third class of satellite molecules, named gammasatellites, is proposed to encompass the increasing number of reported small (<1 kilobase), non-coding begomovirus-associated satellite DNAs. This VEM-based survey indicates that, although recently recovered begomovirus genomes are variations of known genetic themes, satellite DNAs hold unexplored genetic diversity. PMID:26848679

  12. Begomovirus-Associated Satellite DNA Diversity Captured Through Vector-Enabled Metagenomic (VEM) Surveys Using Whiteflies (Aleyrodidae)

    PubMed Central

    Rosario, Karyna; Marr, Christian; Varsani, Arvind; Kraberger, Simona; Stainton, Daisy; Moriones, Enrique; Polston, Jane E.; Breitbart, Mya

    2016-01-01

    Monopartite begomoviruses (Geminiviridae), which are whitefly-transmitted single-stranded DNA viruses known for causing devastating crop diseases, are often associated with satellite DNAs. Since begomovirus acquisition or exchange of satellite DNAs may lead to adaptation to new plant hosts and emergence of new disease complexes, it is important to investigate the diversity and distribution of these molecules. This study reports begomovirus-associated satellite DNAs identified during a vector-enabled metagenomic (VEM) survey of begomoviruses using whiteflies collected in various locations (California (USA), Guatemala, Israel, Puerto Rico, and Spain). Protein-encoding satellite DNAs, including alphasatellites and betasatellites, were identified in Israel, Puerto Rico, and Guatemala. Novel alphasatellites were detected in samples from Guatemala and Puerto Rico, resulting in the description of a phylogenetic clade (DNA-3-type alphasatellites) dominated by New World sequences. In addition, a diversity of small (~640–750 nucleotides) satellite DNAs similar to satellites associated with begomoviruses infecting Ipomoea spp. were detected in Puerto Rico and Spain. A third class of satellite molecules, named gammasatellites, is proposed to encompass the increasing number of reported small (<1 kilobase), non-coding begomovirus-associated satellite DNAs. This VEM-based survey indicates that, although recently recovered begomovirus genomes are variations of known genetic themes, satellite DNAs hold unexplored genetic diversity. PMID:26848679

  13. Spectroscopy of Exoplanet Atmospheres with the FINESSE Explorer

    NASA Technical Reports Server (NTRS)

    Deroo, Pieter; Swain, Mark R.; Green, Robert O.

    2012-01-01

    FINESSE (Fast INfrared Exoplanet Spectroscopic Survey Explorer) will provide uniquely detailed information on the growing number of newly discovered planets by characterizing their atmospheric composition and temperature structure. This NASA Explorer mission, selected for a competitive Phase A study, is unique in its breath and scope thanks to broad instantaneous spectroscopy from the optical to the mid-IR (0.7 - 5 micron), with a survey of exoplanets measured in a consistent, uniform way. For 200 transiting exoplanets ranging from Terrestrial to Jovians, FINESSE will measure the chemical composition and temperature structure of their atmospheres and trace changes over time with exoplanet longitude. The mission will do so by measuring the spectroscopic time series for a primary and secondary eclipse over the exoplanet orbital phase curve. With spectrophotometric precision being a key enabling aspect for combined light exoplanet characterization, FINESSE is designed to produce spectrophotometric precision of better than 100 parts-per-million per spectral channel without the need for decorrelation. The exceptional stability of FINESSE will even allow the mission to characterize non-transiting planets, potentially as part of FINESSE's Participating Scientist Program. In this paper, we discuss the flow down from the target availability to observations and scheduling to the analysis and calibration of the data and how it enables FINESSE to be the mission that will truly expand the new field of comparative exoplanetology.

  14. A contribution towards simplifying area-wide tsetse surveys using medium resolution meteorological satellite data.

    PubMed

    Hendrickx, G; Napala, A; Slingenbergh, J H; De Deken, R; Rogers, D J

    2001-10-01

    A raster or grid-based Geographic Information System with data on tsetse, trypanosomiasis, animal production, agriculture and land use has recently been developed in Togo. The area-wide sampling of tsetse fly, aided by satellite imagery, is the subject of two separate papers. This paper follows on a first paper, published in this journal, describing the generation of digital tsetse distribution and abundance maps and how these accord with the local climatic and agro-ecological setting. Such maps when combined with data on the disease, the hosts and their owners, should contribute to the knowledge of the spatial epidemiology of trypanosomiasis and assist planning of integrated control operations. Here we address the problem of generating tsetse distribution and abundance maps from remotely sensed data, using a restricted amount of field data. Different discriminant analysis models have been applied using contemporary tsetse data and remotely sensed, low resolution data acquired from the National Oceanographic and Atmospheric Administration (NOAA) and Meteosat platforms. The results confirm the potential of satellite data application and multivariate analysis for the prediction of the tsetse distribution and abundance. This opens up new avenues because satellite predictions and field data may be combined to strengthen and/or substitute one another. The analysis shows how the strategic incorporation of satellite imagery may minimize field collection of data. Field surveys may be modified and conducted in two stages, first concentrating on the expected fly distribution limits and thereafter on fly abundance. The study also shows that when applying satellite data, care should be taken in selecting the optimal number of predictor variables because this number varies with the amount of training data for predicting abundance and on the homogeneity of the distribution limits for predicting fly presence. Finally, it is suggested that in addition to the use of contemporary

  15. KELT-10b: the first transiting exoplanet from the KELT-South survey - a hot sub-Jupiter transiting a V = 10.7 early G-star

    NASA Astrophysics Data System (ADS)

    Kuhn, Rudolf B.; Rodriguez, Joseph E.; Collins, Karen A.; Lund, Michael B.; Siverd, Robert J.; Colón, Knicole D.; Pepper, Joshua; Stassun, Keivan G.; Cargile, Phillip A.; James, David J.; Penev, Kaloyan; Zhou, George; Bayliss, Daniel; Tan, T. G.; Curtis, Ivan A.; Udry, Stephane; Segransan, Damien; Mawet, Dimitri; Dhital, Saurav; Soutter, Jack; Hart, Rhodes; Carter, Brad; Gaudi, B. Scott; Myers, Gordon; Beatty, Thomas G.; Eastman, Jason D.; Reichart, Daniel E.; Haislip, Joshua B.; Kielkopf, John; Bieryla, Allyson; Latham, David W.; Jensen, Eric L. N.; Oberst, Thomas E.; Stevens, Daniel J.

    2016-07-01

    We report the discovery of KELT-10b, the first transiting exoplanet discovered using the KELT-South telescope. KELT-10b is a highly inflated sub-Jupiter mass planet transiting a relatively bright V = 10.7 star (TYC 8378-64-1), with Teff = 5948 ± 74 K, log g = 4.319_{-0.030}^{+0.020} and [Fe/H] = 0.09_{-0.10}^{+0.11}, an inferred mass M* = 1.112_{-0.061}^{+0.055} M⊙ and radius R* = 1.209_{-0.035}^{+0.047} R⊙. The planet has a radius Rp = 1.399_{-0.049}^{+0.069} RJ and mass Mp = 0.679_{-0.038}^{+0.039} MJ. The planet has an eccentricity consistent with zero and a semimajor axis a = 0.052 50_{-0.000 97}^{+0.000 86} au. The best-fitting linear ephemeris is T0 = 2457 066.720 45 ± 0.000 27 BJDTDB and P = 4.166 2739 ± 0.000 0063 d. This planet joins a group of highly inflated transiting exoplanets with a larger radius and smaller mass than that of Jupiter. The planet, which boasts deep transits of 1.4 per cent, has a relatively high equilibrium temperature of Teq = 1377_{-23}^{+28} K, assuming zero albedo and perfect heat redistribution. KELT-10b receives an estimated insolation of 0.817_{-0.054}^{+0.068} × 109 erg s-1 cm-2, which places it far above the insolation threshold above which hot Jupiters exhibit increasing amounts of radius inflation. Evolutionary analysis of the host star suggests that KELT-10b may not survive beyond the current subgiant phase, depending on the rate of in-spiral of the planet over the next few Gyr. The planet transits a relatively bright star and exhibits the third largest transit depth of all transiting exoplanets with V < 11 in the Southern hemisphere, making it a promising candidate for future atmospheric characterization studies.

  16. A New Faint Milky Way Satellite Discovered in the Pan-STARRS1 3π Survey

    NASA Astrophysics Data System (ADS)

    Laevens, Benjamin P. M.; Martin, Nicolas F.; Ibata, Rodrigo A.; Rix, Hans-Walter; Bernard, Edouard J.; Bell, Eric F.; Sesar, Branimir; Ferguson, Annette M. N.; Schlafly, Edward F.; Slater, Colin T.; Burgett, William S.; Chambers, Kenneth C.; Flewelling, Heather; Hodapp, Klaus A.; Kaiser, Nicholas; Kudritzki, Rolf-Peter; Lupton, Robert H.; Magnier, Eugene A.; Metcalfe, Nigel; Morgan, Jeffrey S.; Price, Paul A.; Tonry, John L.; Wainscoat, Richard J.; Waters, Christopher

    2015-04-01

    We present the discovery of a faint Milky Way satellite, Laevens 2/Triangulum II, found in the Panoramic Survey Telescope And Rapid Response System 3π imaging data and confirmed with follow-up wide-field photometry from the Large Binocular Cameras. The stellar system, with an absolute magnitude of MV = -1.8 ± 0.5, a heliocentric distance of 30-2+2 kpc, and a half-mass-radius of 34-8+9 pc, shows remarkable similarity to faint, nearby, small satellites such as Willman 1, Segue 1, Segue 2, and Boötes II. The discovery of Laevens 2/Triangulum II further populates the region of parameter space for which the boundary between dwarf galaxies and globular clusters becomes tenuous. Follow-up spectroscopy will ultimately determine the nature of this new satellite, whose spatial location hints at a possible connection with the complex Triangulum-Andromeda stellar structures. The LBT is an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are The University of Arizona on behalf of the Arizona university system; Instituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota, and University of Virginia.

  17. Sampling design for an integrated socioeconomic and ecological survey by using satellite remote sensing and ordination.

    PubMed

    Binford, Michael W; Lee, Tae Jeong; Townsend, Robert M

    2004-08-01

    Environmental variability is an important risk factor in rural agricultural communities. Testing models requires empirical sampling that generates data that are representative in both economic and ecological domains. Detrended correspondence analysis of satellite remote sensing data were used to design an effective low-cost sampling protocol for a field study to create an integrated socioeconomic and ecological database when no prior information on ecology of the survey area existed. We stratified the sample for the selection of tambons from various preselected provinces in Thailand based on factor analysis of spectral land-cover classes derived from satellite data. We conducted the survey for the sampled villages in the chosen tambons. The resulting data capture interesting variations in soil productivity and in the timing of good and bad years, which a purely random sample would likely have missed. Thus, this database will allow tests of hypotheses concerning the effect of credit on productivity, the sharing of idiosyncratic risks, and the economic influence of environmental variability. PMID:15254298

  18. Geology and photometric variation of solar system bodies with minor atmospheres: implications for solid exoplanets.

    PubMed

    Fujii, Yuka; Kimura, Jun; Dohm, James; Ohtake, Makiko

    2014-09-01

    A reasonable basis for future astronomical investigations of exoplanets lies in our best knowledge of the planets and satellites in the Solar System. Solar System bodies exhibit a wide variety of surface environments, even including potential habitable conditions beyond Earth, and it is essential to know how they can be characterized from outside the Solar System. In this study, we provide an overview of geological features of major Solar System solid bodies with minor atmospheres (i.e., the terrestrial Moon, Mercury, the Galilean moons, and Mars) that affect surface albedo at local to global scale, and we survey how they influence point-source photometry in the UV/visible/near IR (i.e., the reflection-dominant range). We simulate them based on recent mapping products and also compile observed light curves where available. We show a 5-50% peak-to-trough variation amplitude in one spin rotation associated with various geological processes including heterogeneous surface compositions due to igneous activities, interaction with surrounding energetic particles, and distribution of grained materials. Some indications of these processes are provided by the amplitude and wavelength dependence of variation in combinations of the time-averaged spectra. We also estimate the photometric precision needed to detect their spin rotation rates through periodogram analysis. Our survey illustrates realistic possibilities for inferring the detailed properties of solid exoplanets with future direct imaging observations. Key Words: Planetary environments-Planetary geology-Solar System-Extrasolar terrestrial planets. PMID:25238324

  19. Geology and Photometric Variation of Solar System Bodies with Minor Atmospheres: Implications for Solid Exoplanets

    PubMed Central

    Kimura, Jun; Dohm, James; Ohtake, Makiko

    2014-01-01

    Abstract A reasonable basis for future astronomical investigations of exoplanets lies in our best knowledge of the planets and satellites in the Solar System. Solar System bodies exhibit a wide variety of surface environments, even including potential habitable conditions beyond Earth, and it is essential to know how they can be characterized from outside the Solar System. In this study, we provide an overview of geological features of major Solar System solid bodies with minor atmospheres (i.e., the terrestrial Moon, Mercury, the Galilean moons, and Mars) that affect surface albedo at local to global scale, and we survey how they influence point-source photometry in the UV/visible/near IR (i.e., the reflection-dominant range). We simulate them based on recent mapping products and also compile observed light curves where available. We show a 5–50% peak-to-trough variation amplitude in one spin rotation associated with various geological processes including heterogeneous surface compositions due to igneous activities, interaction with surrounding energetic particles, and distribution of grained materials. Some indications of these processes are provided by the amplitude and wavelength dependence of variation in combinations of the time-averaged spectra. We also estimate the photometric precision needed to detect their spin rotation rates through periodogram analysis. Our survey illustrates realistic possibilities for inferring the detailed properties of solid exoplanets with future direct imaging observations. Key Words: Planetary environments—Planetary geology—Solar System—Extrasolar terrestrial planets. Astrobiology 14, 753–768. PMID:25238324

  20. BRIGHTEST SATELLITE GALAXY ALIGNMENT OF SLOAN DIGITAL SKY SURVEY GALAXY GROUPS

    SciTech Connect

    Li Zhigang; Wang Yougang; Chen Xuelei; Yang Xiaohu; Xie Lizhi; Wang Xin E-mail: wangygcluster@gmail.com E-mail: lzxie@bao.ac.cn E-mail: wangxin@pha.jhu.edu

    2013-05-01

    We study the alignment signal between the distribution of the brightest satellite galaxies (BSGs) and the major axes of their host groups using the Sloan Digital Sky Survey group catalog constructed by Yang et al. After correcting for the effect of group ellipticity, a statistically significant ({approx}5{sigma}) major-axis alignment is detected and the alignment angle is found to be 43. Degree-Sign 0 {+-} 0. Degree-Sign 4. More massive and richer groups show a stronger BSG alignment. The BSG alignment around blue brightest central galaxies (BCGs) is slightly stronger than that around red BCGs. Red BSGs have a much stronger major-axis alignment than blue BSGs. Unlike BSGs, other satellites do not show very significant alignment with their group's major axis. We further explore BSG alignment using the semi-analytic model (SAM) constructed by Guo et al. In general, we found good agreement of the model with observations: BSGs in the SAM show a strong major-axis alignment that depends on group mass and richness in the same way as in observations and none of the other satellites exhibit prominent alignment. However, a discrepancy also exists in that the SAM shows a BSG color dependence opposite of that in observations, which is most probably induced by a missing large-scale environment ingredient in the SAM. The combination of two popular scenarios can explain the BSG alignment we detected. First, satellites merged into the group along the surrounding filaments, which are strongly aligned with the major axis of the group. Second, BSGs entered their host group more recently than other satellites, so they have preserved more information about their assembling history and major-axis alignment. In the SAM, we found positive evidence for the second scenario in the fact that BSGs merged into groups statistically more recently than other satellites. We also found that most of the BSGs (80%) were BCGs before they merged into groups and earlier merging BSGs tend to be closer to

  1. Foodstuff Survey Around a Major Nuclear Facility with Test of Satellite Image Application

    SciTech Connect

    Fledderman, P.D.

    1999-07-16

    'A foodstuff survey was performed around the Savannah River Site, Aiken SC. It included a census of buildings and fields within 5 km of the boundary and determination of the locations and amounts of crops grown within 80 km of SRS center. Recent information for this region was collected on the amounts of meat, poultry, milk, and eggs produced, of deer hunted, and of sports fish caught. The locations and areas devoted to growing each crop were determined in two ways: by the usual process of assuming uniform crop distribution in each county on the basis of agricultural statistics reported by state agencies, and by analysis of two LANDSAT TM images obtained in May and September. For use with environmental radionuclide transfer and radiation dose calculation codes, locations within 80 km were defined for 64 sections by 16 sectors centered on the Site and by 16-km distance intervals from 16 km to 80 km. Most locally-raised foodstuff was distributed regionally and not retained locally for consumption. For four food crops, the amounts per section based on county agricultural statistics prorated by area were compared with the amounts per section based on satellite image analysis. The median ratios of the former to the latter were 0.6 - 0.7, suggesting that the two approaches are comparable but that satellite image analysis gave consistently higher amounts. Use of satellite image analysis is recommended on the basis of these findings to obtain site-specific, as compared to area-averaged, information on crop locations in conjunction with radionuclide pathway modelling. Some improvements in technique are suggested for satellite image application to characterize additional crops.'

  2. Surveys of elliptical crater populations on the saturnian satellites, Mercury, and Mars

    NASA Astrophysics Data System (ADS)

    Herrick, Robert R.; Schenk, Paul M.; Robbins, Stuart J.

    2012-08-01

    Near-horizontal planetary impacts result in elliptical craters. The percentage of elliptical craters on a planet can be used to infer the impact angle at which craters become elliptical. Previous surveys of the Moon, Mars, and Venus indicated that planetary craters become elliptical at more vertical angles than experimental impacts into a strengthless medium, and this was attributed to a higher ratio of crater diameter to projectile diameter. Here we determined the percentage of elliptical craters on the mid-sized saturnian satellites and Mercury, bodies that represent Solar-System extremes of impactor velocity, target density, and target strength. On the saturnian satellites, 7.6% of the craters have ellipticities e (ratio of major to minor axis) greater than 1.2, but only 0.4% have e > 1.5, and no craters have e > 1.75. On Mercury, 3% of the craters have e > 1.2 and 0.5% have e > 1.5. The mercurian percentages are slightly lower than the other terrestrial planets, attributable to a higher crater diameter to projectile diameter caused by the higher impact velocities at Mercury. We attribute the high percentage of moderately elliptical craters on the saturnian satellites to the rugged target terrain on those bodies. We interpret enhanced crater collapse on the icy surfaces of the saturnian satellites as preventing craters with extremely high ellipticities like the lunar crater Schiller. Finally, a reexamination of the martian crater population shows its elliptical crater population to be consistent with the other planets, and we see little evidence for a large population of craters formed by inward-spiraling moonlets.

  3. THE SPLASH SURVEY: SPECTROSCOPY OF 15 M31 DWARF SPHEROIDAL SATELLITE GALAXIES

    SciTech Connect

    Tollerud, Erik J.; Bullock, James S.; Yniguez, Basilio; Cooper, Michael C. E-mail: bullock@uci.edu E-mail: m.cooper@uci.edu; and others

    2012-06-10

    We present a resolved star spectroscopic survey of 15 dwarf spheroidal (dSph) satellites of the Andromeda galaxy (M31). We filter foreground contamination from Milky Way (MW) stars, noting that MW substructure is evident in this contaminant sample. We also filter M31 halo field giant stars and identify the remainder as probable dSph members. We then use these members to determine the kinematical properties of the dSphs. For the first time, we confirm that And XVIII, XXI, and XXII show kinematics consistent with bound, dark-matter-dominated galaxies. From the velocity dispersions for the full sample of dSphs we determine masses, which we combine with the size and luminosity of the galaxies to produce mass-size-luminosity scaling relations. With these scalings we determine that the M31 dSphs are fully consistent with the MW dSphs, suggesting that the well-studied MW satellite population provides a fair sample for broader conclusions. We also estimate dark matter halo masses of the satellites and find that there is no sign that the luminosity of these galaxies depends on their dark halo mass, a result consistent with what is seen for MW dwarfs. Two of the M31 dSphs (And XV, XVI) have estimated maximum circular velocities smaller than 12 km s{sup -1} (to 1{sigma}), which likely places them within the lowest-mass dark matter halos known to host stars (along with Booetes I of the MW). Finally, we use the systemic velocities of the M31 satellites to estimate the mass of the M31 halo, obtaining a virial mass consistent with previous results.

  4. Preliminary Results of Detailed Chemical Abundance Analysis of Milky Way Satellite Galaxy Reticulum II Discovered in the Dark Energy Survey

    NASA Astrophysics Data System (ADS)

    Nagasawa, Daniel; Marshall, Jennifer L.; Li, Ting; Dark Energy Survey Milky Way Science Group

    2016-01-01

    We present preliminary results from abundance analysis of stars in Milky Way satellite galaxies found in the Dark Energy Survey (DES). DES has discovered 16 candidate satellite galaxies of the Milky Way in its first two years of operation. Since January 2015, three candidates have subsequently been revealed to be dark matter-dominated by spectroscopic follow-up studies of their kinematics, confirming their status as satellite galaxies. Spectroscopic follow-up of the remaining 13 candidates is underway. We have analyzed high resolution VLT/GIRAFFE spectra of member stars in one of these satellite galaxies, Reticulum II. Using equivalent width measurement and spectral synthesis methods, we measure the abundances of Iron and other species in order to begin to understand the chemical content of these Milky Way satellites.

  5. Exoplanet observations with GTC

    NASA Astrophysics Data System (ADS)

    Pallé, Enric

    2015-12-01

    Our group is presently conducting an observational campaign, using the 10-meter Gran Telescopio Canarias (GTC), to obtain the transmission spectrum of several exoplanets during a transit event. The GTC instrument OSIRIS is used in its long-slit spectroscopic mode, covering the spectral range of 520-1040 nm, and observations are taken using a set of custom-built slits of various, broad, widths. We integrate the stellar flux of both stars in different wavelength regions producing several light curves and fit transit models in order to obtain the star-to-planet radius ratio Rp/Rs across wavelength. A Markov Chain Monte Carlo (MCMC) Bayesian approach is used for the transit fitting. We will show that with our instrumental setup, OSIRIS has been able to reach precisions down to 250 ppm (WASP-48b, V=11.06 mag) for each color light curve 10 nm wide, in a single transit. And accuracies of the order of 500ppm can be obtained for objects with V=16. Central transit timing accuracies have been measured down to 6 seconds.Here, we will present refined planet parameters, the detection of planet color signatures, and the transmission spectra of a set of know and unpublished transiting exoplanets. We will also discuss the capabilities and limitations of GTC with current and future instrumentation, and the role of GTC as tool for the follow up of faint exoplanet targets.

  6. 32 New Exoplanets Found

    NASA Astrophysics Data System (ADS)

    2009-10-01

    oday, at an international ESO/CAUP exoplanet conference in Porto, the team who built the High Accuracy Radial Velocity Planet Searcher, better known as HARPS, the spectrograph for ESO's 3.6-metre telescope, reports on the incredible discovery of some 32 new exoplanets, cementing HARPS's position as the world's foremost exoplanet hunter. This result also increases the number of known low-mass planets by an impressive 30%. Over the past five years HARPS has spotted more than 75 of the roughly 400 or so exoplanets now known. "HARPS is a unique, extremely high precision instrument that is ideal for discovering alien worlds," says Stéphane Udry, who made the announcement. "We have now completed our initial five-year programme, which has succeeded well beyond our expectations." The latest batch of exoplanets announced today comprises no less than 32 new discoveries. Including these new results, data from HARPS have led to the discovery of more than 75 exoplanets in 30 different planetary systems. In particular, thanks to its amazing precision, the search for small planets, those with a mass of a few times that of the Earth - known as super-Earths and Neptune-like planets - has been given a dramatic boost. HARPS has facilitated the discovery of 24 of the 28 planets known with masses below 20 Earth masses. As with the previously detected super-Earths, most of the new low-mass candidates reside in multi-planet systems, with up to five planets per system. In 1999, ESO launched a call for opportunities to build a high resolution, extremely precise spectrograph for the ESO 3.6-metre telescope at La Silla, Chile. Michel Mayor, from the Geneva Observatory, led a consortium to build HARPS, which was installed in 2003 and was soon able to measure the back-and-forward motions of stars by detecting small changes in a star's radial velocity - as small as 3.5 km/hour, a steady walking pace. Such a precision is crucial for the discovery of exoplanets and the radial velocity method

  7. A Forest Biomass Survey by Bitterlich Method With an Electronic Relascope for Satellite Data Validation

    NASA Astrophysics Data System (ADS)

    Suzuki, R.; Ishii, R.; Takao, G.; Nakano, T.; Yasuda, T.

    2006-12-01

    For the better understanding of the carbon cycle in the global ecosystem, an investigation on the spatio- temporal variation of the carbon stock which is stored as vegetation biomass should be important. "PALSAR (Phased Array type L-band Synthetic Aperture Radar)", an onboard sensor of the polar orbiting satellite "ALOS (Advanced Land Observing Satellite)" launched in January 2006, provides the information which can be used for the above-ground biomass estimation. It is expected that ALOS/PALSAR provides us a great opportunity to analyze the biomass dynamics over extensive regions. To derive the biomass from the ALOS/PALSAR measurement, it is inevitable to acquire in situ biomass measurement by ground-based forest surveys. Moreover, it is required to obtain such ground-based information at as possible many sites, because the region targeted by satellite remote sensing is extensive and the forest structure in that region is various. Therefore, a quick forest survey will be required to measure the biomass at as possible many sites. For the quick measurement of the forest above-ground biomass, we propose a way that is a combination of Bitterlich angle count sampling method and sampled-tree measuring method. First, a tree which has wider trunk than the basal area factor (BAF) angle is identified by the relascope from a representative point in the target forest. Next, the tree height and the breast height diameter (DBH) of the sampled tree are measured. The biomass of the tree is estimate by the allometric equation with the tree height and DBH measurements. Through these processes, the biomass density of the sampled tree per the forest area defined by the BAF is estimated. By sampling and measuring all trees (usually around 20 trees), the biomass of the forest can be estimate. A brand-new electronic relascope (Criterion RD 1000, Laser Technology Inc.) and laser range finder (TruPulse 200, Laser Technology Inc.) are used for the tree height and DBH measurements to

  8. SEEDS - Strategic explorations of exoplanets and disks with the Subaru Telescope -

    NASA Astrophysics Data System (ADS)

    Tamura, M.

    2016-02-01

    The first convincing detection of planets orbiting stars other than the Sun, or exoplanets, was made in 1995. In only 20 years, the number of the exoplanets including promising candidates has already accumulated to more than 5000. Most of the exoplanets discovered so far are detected by indirect methods because the direct imaging of exoplanets needs to overcome the extreme contrast between the bright central star and the faint planets. Using the large Subaru 8.2-m Telescope, a new high-contrast imager, HiCIAO, and second-generation adaptive optics (AO188), the most ambitious high-contrast direct imaging survey to date for giant planets and planet-forming disks has been conducted, the SEEDS project. In this review, we describe the aims and results of the SEEDS project for exoplanet/disk science. The completeness and uniformity of this systematic survey mean that the resulting data set will dominate this field of research for many years.

  9. Infrared Spectroscopic Imaging Survey (emph{IRSIS}) payload for an Indian satellite

    NASA Astrophysics Data System (ADS)

    Ghosh, S. K.

    The Infrared Spectroscopic Imaging Survey (IRSIS) experiment, targeted for the Small Satellite Mission of the Indian Space Research Organization (ISRO), will carry out spectroscopic measurements in the wavelength range 1.7 to 6.4 μm seamlessly for the first time, covering a large fraction (˜ 50%) of the sky (including the Galactic Plane), with a reasonable sensitivity (completeness at 2.2 μm, K = 14 mag.). The planned Spectral Resolution is ˜ 100. Primary science goals include : (i) Discovery & classification of Brown Dwarfs, M-L-T Dwarfs (faint end of Initial Mass Function); (ii) Large scale mapping in emission features; e.g. Polycyclic Aromatic Hydrocarbon (PAH) at 3.3 μm, 6.2 μm, etc. (Galactic Plane survey); (iii) Minor bodies of Solar System : Asteroids, Comets, Inter- Planetary Dust; Origin, evolution & types of Organics; History of Solar System; and (iv) Asymptotic Giant Branch (AGB), Red-Super-Giant (RSG), Carbon-rich stars; (Galactic Bulge survey). In addition, it will support studies of time critical phenomena like novae, comets etc, under Targets of Opportunity (ToO) observations. The IRSIS database is expected to provide better understanding of energetics and composition of the ISM, infrared characterisation of stars, and various types of Solar system bodies.

  10. Multi-sensor satellite survey of surface oil pollution in the Caspian Sea

    NASA Astrophysics Data System (ADS)

    Mityagina, Marina I.; Lavrova, Olga Y.

    2015-10-01

    The results of long-term satellite survey of the aquatic area of the Caspian Sea are presented. The patterns of surface oil pollution of the Caspian Sea are described and analysed. It is demonstrated that surface oil pollution is often caused by natural causes, namely by natural hydrocarbon seepages and mud volcanoes activity on the sea bottom. A combined analysis of oil film signatures in satellite radar and optical imagery data is performed. Mapping of the main types of surface pollution of the Caspian Sea is performed and areas of the heaviest pollution are outlined and analysed. Dependence of radar signatures of sea surface oil patches on the wind/wave conditions is investigated. The large amount of the data available allowed us to make some generalizations and obtain statistically significant results on a spatial and temporal variability of various sea surface film manifestations in SAR images. The impact of dynamic and circulation processes and natural factors (current meandering, vortical activity, temperature and wind patterns) on spatial and temporal distributions and intensity of oil films is studied. The connection between manifestations of natural seepages and mud volcanoes and earthquake activity in South Caspian and adjacent areas is established.

  11. VLBA Surveys of OH Masers in Star-forming Regions. I. Satellite Lines

    NASA Astrophysics Data System (ADS)

    Ruiz-Velasco, A. E.; Felli, D.; Migenes, V.; Wiggins, B. K.

    2016-05-01

    Using the Very Long Baseline Array we performed a high-resolution OH maser survey in Galactic star-forming regions (SFRs). We observed all the ground state spectral lines: the main lines at 1665 and 1667 MHz and the satellite lines at 1612 and 1720 MHz. Due to the exceptionality of finding satellite lines in SFRs, we will focus our discussion on those lines. In our sample of 41 OH maser sources, five (12%) showed the 1612 MHz line and ten (24%) showed the 1720 MHz line, with only one source showing both lines. We find that 1720 MHz emission is correlated with the presence of H ii regions, suggesting that this emission could be used to diagnose or trace high-mass star formation. We include an analysis of the possible mechanisms that could be causing this correlation as well as assessing the possible relationships between lines in our sample. In particular, the presence of magnetic fields seems to play an important role as we found Zeeman splitting in four of our sources (W75 N, W3(OH), W51 and NGC 7538). Our results have implications for current understanding of the formation of high-mass stars as well as on the masing processes present in SFRs.

  12. Field survey report and satellite image interpretation of the 2013 Super Typhoon Haiyan in the Philippines

    NASA Astrophysics Data System (ADS)

    Mas, E.; Bricker, J.; Kure, S.; Adriano, B.; Yi, C.; Suppasri, A.; Koshimura, S.

    2015-04-01

    Three weeks after the deadly Bohol earthquake of Mw 7.2, which claimed at least 222 victims, another disaster struck the Philippines. This time, Super Typhoon Haiyan, also known as Typhoon Yolanda in the Philippines, devastated the Eastern Visayas islands on 8 November 2013. Its classification as a super typhoon was based on its maximum sustained 1 min surface wind speed of 315 km h-1, which is equivalent to a strong Category 5 hurricane on the Saffir-Simpson scale. This was one of the deadliest typhoon events in the Philippines' history, after the 1897 and 1912 tropical cyclones. At least 6268 individuals have been reported dead and 1061 people are missing. In addition, a wide area of destruction was observed in the Eastern Visayas, on Samar and Leyte islands. The International Research Institute of Disaster Science (IRIDeS) at Tohoku University in Sendai, Japan, has deployed several teams for damage recognition, relief support and collaboration with regard to this disaster event. One of the teams, the hazard and damage evaluation team, visited the affected areas in the Eastern Visayas in mid-January 2014. In this paper, we summarize the rapid damage assessment from satellite imagery conducted days after the event and report on the inundation measurements and the damage surveyed in the field. Damage interpretation results by satellite images were qualitatively confirmed for the Tacloban city area on Leyte Island, the most populated city in the Eastern Visayas. During the survey, significant damage was observed from wind and storm surges on poorly designed housing on the east coast of Leyte Island. Damage, mainly from surface waves and winds, was observed on the east coast of Samar Island.

  13. Renewed uplift at the Yellowstone caldera measured by leveling surveys and satellite radar interferometry

    USGS Publications Warehouse

    Dzurisin, D.; Wicks, C.; Thatcher, W.

    1999-01-01

    A first-order leveling survey across the northeast part of the Yellowstone caldera in September 1998 showed that the central caldera floor near Le Hardy Rapids rose 24 ?? 5 mm relative to the caldera rim at Lake Butte since the previous survey in September 1995. Annual surveys along the same traverse from 1985 to 1995 tracked progressive subsidence near Le Hardy Rapids at an average rate of -19 ?? 1 mm/year. Earlier, less frequent surveys measured net uplift in the same area during 1923-1976 (14 ?? 1 mm/year) and 1976-1984 (22 ?? 1 mm/year). The resumption of uplift following a decade of subsidence was first detected by satellite synthetic aperture radar interferometry, which revealed approximately 15 mm of uplift in the vicinity of Le Hardy Rapids from July 1995 to June 1997. Radar interferograms show that the center of subsidence shifted from the Sour Creek resurgent dome in the northeast part of the caldera during August 1992 to June 1993 to the Mallard Lake resurgent dome in the southwest part during June 1993 to August 1995. Uplift began at the Sour Creek dome during August 1995 to September 1996 and spread to the Mallard Lake dome by June 1997. The rapidity of these changes and the spatial pattern of surface deformation suggest that ground movements are caused at least in part by accumulation and migration of fluids in two sill-like bodies at 5-10 km depth, near the interface between Yellowstone's magmatic and deep hydrothermal systems.

  14. Exoplanet Orbit Database. II. Updates to Exoplanets.org

    NASA Astrophysics Data System (ADS)

    Han, Eunkyu; Wang, Sharon X.; Wright, Jason T.; Feng, Y. Katherina; Zhao, Ming; Fakhouri, Onsi; Brown, Jacob I.; Hancock, Colin

    2014-09-01

    The Exoplanet Orbit Database (EOD) compiles orbital, transit, host star, and other parameters of robustly-detected exoplanets reported in the peer-reviewed literature. The EOD can be navigated through the Exoplanet Data Explorer (EDE) plotter and table, available on the World Wide Web at exoplanets.org. The EOD contains data for 1492 confirmed exoplanets as of 2014 July. The EOD descends from a table provided by Butler and coworkers in 2002 and the Catalog of Nearby Exoplanets (Butler and coworkers in 2006), and the first complete documentation for the EOD and the EDE was presented by Wright and coworkers in 2011. In this work, we describe our work since then. We have expanded the scope of the EOD to include secondary eclipse parameters and asymmetric uncertainties and expanded the EDE to include the sample of over 3000 Kepler Objects of Interest (KOIs) and other real planets without good orbital parameters (such as many of those detected by microlensing and imaging). Users can download the latest version of the entire EOD as a single comma separated value file from the front page of exoplanets.org.

  15. Remote Sensing by Satellite for Environmental Education: A Survey and a Proposal for Teaching at Upper Secondary and University Level.

    ERIC Educational Resources Information Center

    Bosler, Ulrich

    Knowledge of the environment has grown to such an extent that information technology (IT) is essential to make sense of the available data. An example of this is remote sensing by satellite. In recent years this field has grown in importance and remote sensing is used for a range of uses including the automatic survey of wheat yields in North…

  16. A satellite geodetic survey of large-scale deformation of volcanic centres in the central Andes.

    PubMed

    Pritchard, Matthew E; Simons, Mark

    2002-07-11

    Surface deformation in volcanic areas usually indicates movement of magma or hydrothermal fluids at depth. Stratovolcanoes tend to exhibit a complex relationship between deformation and eruptive behaviour. The characteristically long time spans between such eruptions requires a long time series of observations to determine whether deformation without an eruption is common at a given edifice. Such studies, however, are logistically difficult to carry out in most volcanic arcs, as these tend to be remote regions with large numbers of volcanoes (hundreds to even thousands). Here we present a satellite-based interferometric synthetic aperture radar (InSAR) survey of the remote central Andes volcanic arc, a region formed by subduction of the Nazca oceanic plate beneath continental South America. Spanning the years 1992 to 2000, our survey reveals the background level of activity of about 900 volcanoes, 50 of which have been classified as potentially active. We find four centres of broad (tens of kilometres wide), roughly axisymmetric surface deformation. None of these centres are at volcanoes currently classified as potentially active, although two lie within about 10 km of volcanoes with known activity. Source depths inferred from the patterns of deformation lie between 5 and 17 km. In contrast to the four new sources found, we do not observe any deformation associated with recent eruptions of Lascar, Chile. PMID:12110886

  17. A satellite geodetic survey of large-scale deformation of volcanic centres in the central Andes

    NASA Astrophysics Data System (ADS)

    Pritchard, Matthew E.; Simons, Mark

    2002-07-01

    Surface deformation in volcanic areas usually indicates movement of magma or hydrothermal fluids at depth. Stratovolcanoes tend to exhibit a complex relationship between deformation and eruptive behaviour. The characteristically long time spans between such eruptions requires a long time series of observations to determine whether deformation without an eruption is common at a given edifice. Such studies, however, are logistically difficult to carry out in most volcanic arcs, as these tend to be remote regions with large numbers of volcanoes (hundreds to even thousands). Here we present a satellite-based interferometric synthetic aperture radar (InSAR) survey of the remote central Andes volcanic arc, a region formed by subduction of the Nazca oceanic plate beneath continental South America. Spanning the years 1992 to 2000, our survey reveals the background level of activity of about 900 volcanoes, 50 of which have been classified as potentially active. We find four centres of broad (tens of kilometres wide), roughly axisymmetric surface deformation. None of these centres are at volcanoes currently classified as potentially active, although two lie within about 10km of volcanoes with known activity. Source depths inferred from the patterns of deformation lie between 5 and 17km. In contrast to the four new sources found, we do not observe any deformation associated with recent eruptions of Lascar, Chile.

  18. ExoplanetSat: detecting transiting exoplanets using a low-cost CubeSat platform

    NASA Astrophysics Data System (ADS)

    Smith, Matthew W.; Seager, Sara; Pong, Christopher M.; Villaseñor, Jesus S.; Ricker, George R.; Miller, David W.; Knapp, Mary E.; Farmer, Grant T.; Jensen-Clem, Rebecca

    2010-07-01

    Nanosatellites, i.e. spacecraft that weigh between 1 and 10 kg, are drawing increasing interest as platforms for conducting on-orbit science. This trend is primarily driven by the ability to piggyback nanosatellites on the launch of large spacecraft and hence achieve orbit at greatly reduced cost. The CubeSat platform is a standardized nanosatellite configuration, consisting of one, two, or three 10 cm x 10 cm x 10 cm units (1, 2, or 3 "U"s) arranged in a row. We present a CubeSat-based concept for the discovery of transiting exoplanets around the nearest and brightest Sun-like stars. The spacecraft prototype - termed ExoplanetSat - is a 3U space telescope capable of monitoring a single target star from low Earth orbit. Given the volume limitations of the CubeSat form factor, designing a capable spacecraft requires overcoming significant challenges. This work presents the initial satellite configuration along with several subsystem-specific solutions to the aforementioned constraints. An optical design based on a modified commercial off-the-shelf camera lens is given. We also describe a novel two-stage attitude control architecture that combines 3-axis reaction wheels for coarse pointing with a piezoelectric translation stage at the focal plane for fine pointing. Modeling and simulation results are used to demonstrate feasibility by quantifying ExoplanetSat pointing precision, signal-to-noise ratio, guide star magnitude, and additional design parameters which determine system performance.

  19. Understanding Young Exoplanet Analogs with WISE

    NASA Astrophysics Data System (ADS)

    Rice, Emily

    We propose to tackle outstanding questions about the fundamental properties of young brown dwarfs, which are atmospheric analogs to massive gas giant exoplanets, using public archive data from the Wide-field Infrared Survey Explorer (WISE) combined with our extensive dataset of optical and near-infrared observations, including spectra, proper motions, and parallaxes. Using WISE data we will construct color-color diagrams, color- magnitude diagrams, and spectral energy distributions for our sample of candidate young brown dwarfs. We will fully characterize the spectral properties of the candidates and evaluate their membership in nearby young moving groups in order to obtain independent age estimates. The practical outcomes of this project will allow the research community to use observed colors and spectra to reliably constrain the properties - including effective temperature, gravity, and dust/cloud properties - of both brown dwarfs and gas giant exoplanets. We will also search for new young brown dwarfs in the WISE archive using colors and proper motions. The expanded sample of young brown dwarfs will be used to create a self-contained feedback loop to identify and address the shortcomings of cool atmosphere models and low-mass evolutionary tracks, both of which are already being used to infer the properties of massive exoplanets. Disentangling the effects of physical parameters on the observed properties of young brown dwarfs is directly relevant to studies of exoplanets. Direct observations of exoplanets are currently very limited, and young brown dwarfs are the laboratories in which we can solve existing problems before the onslaught of new observations from instruments capable of directly imaging exoplanets, including the Gemini Planet Imager, Project 1640 at the Palomar Observatory, SPHERE on the VLT, and the James Webb Space Telescope. This project addresses the goal of the NASA Science Mission Directorate to discover how the universe works; in particular

  20. Lightest exoplanet yet discovered

    NASA Astrophysics Data System (ADS)

    2009-04-01

    Well-known exoplanet researcher Michel Mayor today announced the discovery of the lightest exoplanet found so far. The planet, "e", in the famous system Gliese 581, is only about twice the mass of our Earth. The team also refined the orbit of the planet Gliese 581 d, first discovered in 2007, placing it well within the habitable zone, where liquid water oceans could exist. These amazing discoveries are the outcome of more than four years of observations using the most successful low-mass-exoplanet hunter in the world, the HARPS spectrograph attached to the 3.6-metre ESO telescope at La Silla, Chile. ESO PR Photo 15a/09 Artist's impression of Gliese 581 e ESO PR Photo 15b/09 A planet in the habitable zone ESO PR Video 15a/09 ESOcast 6 ESO PR Video 15b/09 VNR A-roll ESO PR Video 15c/09 Zoom-in on Gliese 581 e ESO PR Video 15d/09 Artist's impression of Gliese 581 e ESO PR Video 15e/09 Artist's impression of Gliese 581 d ESO PR Video 15f/09 Artist's impression of Gliese 581 system ESO PR Video 15g/09 The radial velocity method ESO PR Video 15h/09 Statement in English ESO PR Video 15i/09 Statement in French ESO PR Video 15j/09 La Silla Observatory "The holy grail of current exoplanet research is the detection of a rocky, Earth-like planet in the ‘habitable zone' -- a region around the host star with the right conditions for water to be liquid on a planet's surface", says Michel Mayor from the Geneva Observatory, who led the European team to this stunning breakthrough. Planet Gliese 581 e orbits its host star - located only 20.5 light-years away in the constellation Libra ("the Scales") -- in just 3.15 days. "With only 1.9 Earth-masses, it is the least massive exoplanet ever detected and is, very likely, a rocky planet", says co-author Xavier Bonfils from Grenoble Observatory. Being so close to its host star, the planet is not in the habitable zone. But another planet in this system appears to be. From previous observations -- also obtained with the HARPS spectrograph

  1. Chemical modeling of exoplanet atmospheres

    NASA Astrophysics Data System (ADS)

    Venot, O.; Agúndez, M.

    2015-12-01

    The past twenty years have revealed the diversity of planets that exist in the Universe. It turned out that most of exoplanets are different from the planets of our Solar System and thus, everything about them needs to be explored. Thanks to current observational technologies, we are able to determine some information about the atmospheric composition the thermal structure and the dynamics of these exoplanets, but many questions remain still unanswered. To improve our knowledge about exoplanetary systems, more accurate observations are needed and that is why the Exoplanet Characterisation Observatory (EChO) is an essential space mission. Thanks to its large spectral coverage and high spectral resolution, EChO will provide exoplanetary spectra with an unprecedented accuracy, allowing to improve our understanding of exoplanets. In this work, we review what has been done to date concerning the chemical modeling of exoplanet atmospheres and what are the main characteristics of warm exoplanet atmospheres, which are one of the main targets of EChO. Finally we will present the ongoing developments that are necessary for the chemical modeling of exoplanet atmospheres.

  2. Saturn as a Transiting Exoplanet

    NASA Astrophysics Data System (ADS)

    Dalba, Paul A.; Muirhead, Philip S.; Fortney, Jonathan J.; Hedman, Matthew M.; Nicholson, Philip D.; Veyette, Mark J.

    2015-11-01

    Previous investigations of exoplanet atmospheres have not targeted those resembling the gas giant planets in our solar system. These types of exoplanets are too cold to be directly imaged or observed in emission, and their low transit probabilities and frequencies make characterization via transmission spectroscopy a challenging endeavor. However, studies of cold giant exoplanets would be highly valuable to our understanding of planet formation and migration and could place the gas giant members of our own solar system in a greater context. Here, we use solar occultations observed by the Visual and Infrared Mapping Spectrometer aboard the Cassini Spacecraft to extract the 1 to 5 μm transmission spectrum of Saturn, as if it were a transiting exoplanet. We detect absorption features from several molecules despite the presence of ammonia clouds. Self-consistent exoplanet atmosphere models show good agreement with Saturn's transmission spectrum but fail to reproduce the largest feature in the spectrum. We also find that atmospheric refraction determines the minimum altitude that could be probed during mid-transit of a Saturn-twin exoplanet around a Sun-like star. These results suggest that transmission spectroscopy of cold, long-period gaseous exoplanets should be possible with current and future observatories.

  3. Characterizing Transiting Exoplanet Atmospheres with Gemini/GMOS: First Results

    NASA Astrophysics Data System (ADS)

    Huitson, Catherine; Desert, Jean-Michel; Bean, Jacob; Fortney, Jonathan J.; Stevenson, Kevin B.; Bergmann, Marcel

    2015-01-01

    We present the first results from a 4-year ground-based survey of nine transiting exoplanet atmospheres. The program uses the Multi-Object Spectrograph (GMOS) on both Gemini north and south to repetitively measure transit lightcurves of individual exoplanets at high spectrophotometric precision. I will present the first results from this program. We attain photometric precisions per spectral bin of 200-600 ppm. Such precision enables us to construct transmission spectra of hot Jupiters. These transmission spectra reveal the dominant upper-atmosphere absorbers in the optical bandpass. Our overarching goal is to understand the prevalence and formation of high altitude clouds and hazes, and other important atmospheric constituents.

  4. Relativity and Exoplanets: Gravitational Microlensing, Doppler Beaming, and More

    NASA Astrophysics Data System (ADS)

    Gaudi, Scott

    2016-03-01

    Perhaps surprisingly, the theories of both special and general relativity play important roles in several areas of exoplanet research. I will review the most important and intriguing of these applications. The most obvious case is gravitational microlensing, which has become a fairly routine method of finding planets, and is poised to become even more important in the next decade. I will also briefly survey the numerous other areas where relativity plays a role in exoplanet theory and observations, including photometric Doppler beaming, general relativistic precession, transits of compact objects, and even (potentially) gravitational wave experiments.

  5. Search of Exoplanets - Phase I

    NASA Astrophysics Data System (ADS)

    Vodniza, Alberto Q.; Pereira, M. R.; Lopez, J. P.; Reyes, K.; Chaves, L.

    2008-09-01

    From the Astronomical Observatory at the University of Nariño-COLOMBIA, we have begun a systematic search for exoplanets. Initially we made differential photometry on variable stars weaker than the tenth magnitude to get enough experience on the establishment of stellar transits, so then we could undertake the work with exoplanets. We have already confirmed the transits of two exoplanets with good photometry data: At the exoplanet HAT-P-5b, discovered by Bakos and other investigators and which turns around the GSC 02634-01087, with an orbital period of 2.788491 days according to measurements of the discoverers, and also at the exoplanet TrES-3, discovered by O'Donovan and other investigators and which turns around the GSC 03089-00929, with an orbital period of 1.30619 days, established by its discoverers. Both exoplanets are quite interesting because they have one of the smallest periods found on exoplanets. The TrES-3 also provides a big opportunity for studying the orbital decay and mass loss due to evaporation, caused by the great closeness to its star. We have captured a lot of data to elaborate the lightcurves so we can estimate physical parameters of the bodies. We are getting data on various dates. Actually we are preparing the equipment to develop observations of radial velocities through spectrometry. In a later phase, we expect to verify the presence of other exoplanets which cause less deep transits, and then we can investigate stars with possible exoplanets around them. Besides we hope to design a mathematical model of the studied systems. The equipment we employed is: 14"LX200 GPS MEADE telescope, ST-7XME SBIG camera, STL-1001 SBIG camera, LHIRES III Spectrograph, and SGS-SBIG Spectrograph. On the poster it is explained at length the methodology followed over the search, the data we obtained and the physical- mathematical analysis that was carried out.

  6. History of water loss and atmospheric O2 buildup on rocky exoplanets near M dwarfs

    NASA Astrophysics Data System (ADS)

    Tian, Feng

    2015-12-01

    It is recently proposed that early stellar luminosity evolution of M dwarfs leads to severe water loss and the buildup of massive O2 atmospheres on rocky exoplanets in the habitable zone of these stars if interactions of such O2 atmospheres with planetary surfaces are inefficient. Here we show that even without considering atmosphere-surface interactions, the existence of a massive O2 atmosphere on such exoplanets is not an unavoidable consequence around M0-M3 stars and depends on stellar XUV properties, the mass of the exoplanets, and most importantly the initial planetary water inventories. In the case of inefficient atmosphere-surface interactions, the distribution of atmospheric O2 contents on these exoplanets should be bi-modal and such a distribution could be verified by future surveys of rocky exoplanets.

  7. GhostNet marine debris survey in the Gulf of Alaska--satellite guidance and aircraft observations.

    PubMed

    Pichel, William G; Veenstra, Timothy S; Churnside, James H; Arabini, Elena; Friedman, Karen S; Foley, David G; Brainard, Russell E; Kiefer, Dale; Ogle, Simeon; Clemente-Colón, Pablo; Li, Xiaofeng

    2012-01-01

    Marine debris, particularly debris that is composed of lost or abandoned fishing gear, is recognized as a serious threat to marine life, vessels, and coral reefs. The goal of the GhostNet project is the detection of derelict nets at sea through the use of weather and ocean models, drifting buoys and satellite imagery to locate convergent areas where nets are likely to collect, followed by airborne surveys with trained observers and remote sensing instruments to spot individual derelict nets. These components of GhostNet were first tested together in the field during a 14-day marine debris survey of the Gulf of Alaska in July and August 2003. Model, buoy, and satellite data were used in flight planning. A manned aircraft survey with visible and IR cameras and a LIDAR instrument located debris in the targeted locations, including 102 individual pieces of debris of anthropogenic or terrestrial origin. PMID:22088492

  8. Spectral Signatures of WFIRST-AFTA Exoplanet Coronagraphy Targets

    NASA Astrophysics Data System (ADS)

    Lewis, Nikole K.; Marley, Mark S.; Lupu, Roxana E.; Fortney, Jonathan J.; Morley, Caroline; Greene, Thomas P.; Robinson, Tyler D.; Visscher, Channon; Freedman, Richard; Line, Michael R.; Traub, Wesley A.

    2016-01-01

    A key component of the WFIRST-AFTA mission is high contrast imaging of planets and debris disks around nearby stars. It is expected that the WFIRST-AFTA mission will be able to characterize around a dozen exoplanets, many of which are already known to exist from current radial velocity surveys. These planets will possess a broad range of atmospheric properties, including a number of possible cloud species and atmospheric compositions. In preparation for the WFIRST-AFTA mission, our team is constructing a library of relevant theoretical spectra and performing spectral retrieval analyses to assess the robustness with which WFIRST-AFTA will be able to characterize exoplanet atmospheres. Here we present our initial findings for a subset of the known exoplanet population that will likely be prime targets for the WFIRST-AFTA mission.

  9. Future of High-Dimensional Data-Driven Exoplanet Science

    NASA Astrophysics Data System (ADS)

    Ford, Eric B.

    2016-03-01

    The detection and characterization of exoplanets has come a long way since the 1990’s. For example, instruments specifically designed for Doppler planet surveys feature environmental controls to minimize instrumental effects and advanced calibration systems. Combining these instruments with powerful telescopes, astronomers have detected thousands of exoplanets. The application of Bayesian algorithms has improved the quality and reliability with which astronomers characterize the mass and orbits of exoplanets. Thanks to continued improvements in instrumentation, now the detection of extrasolar low-mass planets is limited primarily by stellar activity, rather than observational uncertainties. This presents a new set of challenges which will require cross-disciplinary research to combine improved statistical algorithms with an astrophysical understanding of stellar activity and the details of astronomical instrumentation. I describe these challenges and outline the roles of parameter estimation over high-dimensional parameter spaces, marginalizing over uncertainties in stellar astrophysics and machine learning for the next generation of Doppler planet searches.

  10. Stellar Spectroscopy during Exoplanet Transits: Revealing structures across stellar surfaces

    NASA Astrophysics Data System (ADS)

    Dravins, Dainis; Ludwig, Hans-Günter; Dahlén, Erik

    2015-08-01

    Exoplanet transits permit to study stellar surface portions that successively become hidden behind the planet. Differential spectroscopy between various transit phases reveals spectra of those stellar surface segments that were hidden. The deduced center-to-limb behavior of stellar spectral line shapes, asymmetries and wavelength shifts enables detailed tests of 3-dimensional hydrodynamic models of stellar atmospheres, such that are required for any precise determination of abundances or seismic properties. Such models can now be computed for widely different classes of stars (including metal-poor ones and white dwarfs), but have been feasible to test and verify only for the Sun with its resolved surface structure. Exoplanet transits may also occur across features such as starspots, whose magnetic signatures will be retrieved from spectra of sufficient fidelity.Knowing the precise background stellar spectra, also properties of exoplanet atmospheres are better constrained: e.g., the Rossiter-McLaughlin effect becomes resolved as not only a simple change of stellar wavelength, but as a variation of the full line profiles and their asymmetries.Such studies are challenging since exoplanets cover only a tiny fraction of the stellar disk. Current work, analyzing sequences of high-fidelity ESO UVES spectra, demonstrate that such spatially resolved stellar spectra can already be (marginally) retrieved in a few cases with the brightest host stars. Already in a near future, ongoing exoplanet surveys are likely to find further bright hosts that will enable such studies for various stellar types. http://arxiv.org/abs/1408.1402

  11. Geometric accuracy improvement and verification of remote sensing image product for the ZY-3 surveying and mapping satellite

    NASA Astrophysics Data System (ADS)

    Wang, Xia; Zhou, Ping; Guo, Li

    2015-12-01

    Based on the geometric characteristic of ZY3 surveying and mapping satellite, this paper analyses the main error sources of the geometric accuracy of ZY3 satellite image product, and proposes a key technique to improve the accuracy of geometric positioning of ZY-3 satellite image products without the Ground Control Points. Firstly, 556 ZY-3 satellite images distributed in the central western China, with an area of 350 million km2, were used for the planar positioning accuracy verification. The results show that the planar accuracy of ZY-3 image without the GCPs is about 10.8 meters (1σ), and more than 96.9% of experimental image without the GCPs have the planar accuracy higher than 25 meters. Subsequently, the Digital Surface Model (DSM) produced by the ZY-3 three linear array image in Shanxi without the GCPs and the high-precise Lidar-DEM were compared. The comparison shows that overall vertical accuracy of DSM is higher than 6 meters (1σ), and higher than 5.5 and 6.4 meters (1σ) in plane and mountainous area respectively. So the validation confirmed the overall accuracy of ZY-3 satellite images, indicating that ZY-3 satellite can achieve a higher geometric accuracy.

  12. KEPLER OBSERVATIONS OF THREE PRE-LAUNCH EXOPLANET CANDIDATES: DISCOVERY OF TWO ECLIPSING BINARIES AND A NEW EXOPLANET

    SciTech Connect

    Howell, Steve B.; Rowe, Jason F.; Bryson, Stephen T.; Sherry, William; Von Braun, Kaspar; Ciardi, David R.; Feldmeier, John J.; Horch, Elliott; Van Belle, Gerard T.

    2010-12-20

    Three transiting exoplanet candidate stars were discovered in a ground-based photometric survey prior to the launch of NASA's Kepler mission. Kepler observations of them were obtained during Quarter 1 of the Kepler mission. All three stars are faint by radial velocity follow-up standards, so we have examined these candidates with regard to eliminating false positives and providing high confidence exoplanet selection. We present a first attempt to exclude false positives for this set of faint stars without high-resolution radial velocity analysis. This method of exoplanet confirmation will form a large part of the Kepler mission follow-up for Jupiter-sized exoplanet candidates orbiting faint stars. Using the Kepler light curves and pixel data, as well as medium-resolution reconnaissance spectroscopy and speckle imaging, we find that two of our candidates are binary stars. One consists of a late-F star with an early M companion, while the other is a K0 star plus a late M-dwarf/brown dwarf in a 19 day elliptical orbit. The third candidate (BOKS-1) is an r = 15 G8V star hosting a newly discovered exoplanet with a radius of 1.12 R{sub Jupiter} in a 3.9 day orbit.

  13. Minerva: Big Exoplanet Science from Small Telescopes

    NASA Astrophysics Data System (ADS)

    McCrady, Nate

    2012-10-01

    The Kepler mission has identified over 2300 candidate planets in the past two years, adding to the over 500 confirmed exoplanets from radial velocity (RV) surveys. One of the most striking results of these surveys is that the number of planets increases rapidly with decreasing size. There may in fact be more Earth-like planets in the Galaxy than stars. There must be terrestrial planets around nearby stars, though few have yet been discovered. Finding these planets requires high precision RV observations and high cadence transit observing to densely sample the orbital phase. Minerva will surmount these obstacles with a dedicated observatory for detection of super-Earths and close-in Earth-like planets. Our array of four 0.7-m telescopes will operate in two modes: jointly with a high precision fiber-fed spectrometer capable of detecting the RV signal of an Earth orbiting a low mass star, and independently for photometric transit detection surveys.

  14. Weird Warm Spot on Exoplanet

    NASA Video Gallery

    This animation illustrates an unexpected warm spot on the surface of a gaseous exoplanet. NASA's Spitzer Space Telescope discovered that the hottest part of the planet, shown here as bright, orange...

  15. A Cloudy View of Exoplanets

    NASA Technical Reports Server (NTRS)

    Deming, Drake

    2010-01-01

    The lack of absorption features in the transmission spectrum of exoplanet GJ1214b rules out a hydrogen-rich atmosphere for the planet. It is consistent with an atmosphere rich in water vapour or abundant in clouds.

  16. Exoplanet Clouds in the Laboratory

    NASA Astrophysics Data System (ADS)

    Johnson, Alexandria; Cziczo, Daniel J.; Seager, Sara; Charbonneau, David; Bauer, Amy J. R.

    2015-12-01

    The lack of strong spectral features of some exoplanet atmospheres may suggest the presence of a cloud layer and poses great challenges for atmospheric characterization. We aim to address these observations and the challenges by leveraging lab-based terrestrial cloud particle instrumentation as a means of investigating how particles representative of those in exoplanet atmospheres interact with incoming radiation. In the end we hope to achieve two goals - First, to better understand the observable properties of cloud particles in exoplanet atmospheres. Second, to determine how these clouds might directly limit our ability to observe and characterize the atmosphere below.In this presentation I will discuss the cloud chamber used for this work, how we leverage terrestrial based cloud knowledge, our initial investigation of the light scattered by ammonium nitrate (NH4NO3) across temperature and relative humidity dependent phase changes, and future work with suspected exoplanet atmospheric condensates under various atmospheric compositions, pressures, and temperatures.

  17. Field survey report and satellite image interpretation of the 2013 Super Typhoon Haiyan in the Philippines

    NASA Astrophysics Data System (ADS)

    Mas, E.; Bricker, J.; Kure, S.; Adriano, B.; Yi, C.; Suppasri, A.; Koshimura, S.

    2014-05-01

    Three weeks after the deadly Bohol earthquake of magnitude Mw 7.2, which claimed at least 222 victims; another disaster struck the Philippines. This time, Super Typhoon Haiyan, also known as Typhoon Yolanda in the Philippines, devastated the Eastern Visayas islands on 8 November 2013. Its classification as a Super Typhoon was based on its maximum sustained 1 min surface wind speed of 315 km h-1, which is equivalent to a strong Category 5 hurricane on the Saffir-Simpson Scale. This was one of the deadliest typhoon events in the Philippines' history, after the 1897 and 1912 tropical cyclones. At least 6268 individuals have been reported dead and 1061 people are missing. In addition, a wide area of destruction was observed in the Eastern Visayas, on Samar and Leyte Islands. The International Research Institute of Disaster Science (IRIDeS) at Tohoku University in Sendai, Japan has deployed several teams for damage recognition, relief support and collaboration with regard to this disaster event. One of the teams, the hazard and damage evaluation team, visited the affected areas in the Eastern Visayas in mid-January 2014. In this paper, we summarize the rapid damage assessment conducted days after the event and report on the inundation measurements and the damage surveyed in the field. Damage interpretation results by satellite images were qualitatively confirmed for the Tacloban city area on Leyte Island, the most populated city in the Eastern Visayas. During the survey, significant damage was observed from wind and storm surges on poorly designed housing on the east coast of Leyte Island. Damage, mainly from surface waves and winds was observed on the east coast of Samar Island.

  18. Visualising Astronomy: Visualising Exoplanets

    NASA Astrophysics Data System (ADS)

    Wyatt, R.

    2012-05-01

    In my previous column1, I described some of the varied means of diagramming the data about exoplanets and exoplanetary systems. Frankly, however, those methods don't do justice to the bigger picture: we need a wider range of tools to help people grok2 (to understand intuitively) what astronomical observations have revealed. (Normally, I use the term "visualisation" to refer to the visual representation of data, but I'm going to relax that a little in this context; instead, I'll interpret the word in its more commonplace usage of creating a mental image.) How can we help people comprehend the scope, the breadth, and the impact of the spectacular observations of planets around other stars?

  19. Observations of Exoplanet Atmospheres

    NASA Astrophysics Data System (ADS)

    Crossfield, Ian J. M.

    2015-10-01

    Detailed characterization of an extrasolar planet's atmosphere provides the best hope for distinguishing the makeup of its outer layers, and the only hope for understanding the interplay between initial composition, chemistry, dynamics and circulation, and disequilibrium processes. In recent years, some areas have seen rapid progress, while developments in others have come more slowly and/or have been hotly contested. This article gives an observer's perspective on the current understanding of extrasolar planet atmospheres prior to the considerable advances expected from the next generation of observing facilities. Atmospheric processes of both transiting and directly imaged planets are discussed, including molecular and atomic abundances, cloud properties, thermal structure, and planetary energy budgets. In the future we can expect a continuing and accelerating stream of new discoveries, which will fuel the ongoing exoplanet revolution for many years to come.

  20. Structure of exoplanets.

    PubMed

    Spiegel, David S; Fortney, Jonathan J; Sotin, Christophe

    2014-09-01

    The hundreds of exoplanets that have been discovered in the past two decades offer a new perspective on planetary structure. Instead of being the archetypal examples of planets, those of our solar system are merely possible outcomes of planetary system formation and evolution, and conceivably not even especially common outcomes (although this remains an open question). Here, we review the diverse range of interior structures that are both known and speculated to exist in exoplanetary systems--from mostly degenerate objects that are more than 10× as massive as Jupiter, to intermediate-mass Neptune-like objects with large cores and moderate hydrogen/helium envelopes, to rocky objects with roughly the mass of Earth. PMID:24379369

  1. Geoengineering on exoplanets

    NASA Astrophysics Data System (ADS)

    Lockley, Andrew

    2015-04-01

    Solar radiation management (SRM) geoengineering can be used to deliberately alter the Earth's radiation budget, by reflecting sunlight to space. SRM has been suggested as a response to Anthropogenic Global Warming (AGW), to partly or fully balance radiative forcing from AGW [1]. Approximately 22% of sun-like stars have Earth-like exoplanets[2]. Advanced civilisations may exist on these, and may use geoengineering for positive or negative radiative forcing. Additionally, terraforming projects [e.g. 3], may be used to expand alien habitable territory, or for resource management or military operations on non-home planets. Potential observations of alien geoengineering and terraforming may enable detection of technologically advanced alien civilisations, and may help identify widely-used and stable geoengineering technologies. This knowledge may assist the development of safe and stable geoengineering methods for Earth. The potential risks and benefits of possible alien detection of Earth-bound geoengineering schemes must be considered before deployment of terrestrial geoengineering schemes.

  2. Structure of exoplanets

    PubMed Central

    Spiegel, David S.; Fortney, Jonathan J.; Sotin, Christophe

    2014-01-01

    The hundreds of exoplanets that have been discovered in the past two decades offer a new perspective on planetary structure. Instead of being the archetypal examples of planets, those of our solar system are merely possible outcomes of planetary system formation and evolution, and conceivably not even especially common outcomes (although this remains an open question). Here, we review the diverse range of interior structures that are both known and speculated to exist in exoplanetary systems—from mostly degenerate objects that are more than 10× as massive as Jupiter, to intermediate-mass Neptune-like objects with large cores and moderate hydrogen/helium envelopes, to rocky objects with roughly the mass of Earth. PMID:24379369

  3. Coral Reef Dynamics: Integrating Field Survey, and Satellite Image Data to Monitor and Model Biogeophysical Dynamics

    NASA Astrophysics Data System (ADS)

    Phinn, S. R.; Roelfsema, C.; Leon, J.; Borrego, R.; Canto, R.; Joyce, K.; McGowan, H. A.; Mackellar, M. C.

    2012-12-01

    Developing a complete understanding of the contemporary biogeophysical processes shaping coral reef ecosystems requires integration across multiple disciplines. This paper outlines the results obtained across multiple disciplinary projects for developing an integrated understanding of the biogeophysical processes shaping Heron Reef, on the Great Barrier Reef Australia. Heron Reef is a lagoonal platform reef on the southern Great Reef, with a small coral cay on its western edge. Over the past 10 years the nature of research undertaken On Heron reef has moved from plot-scale field surveys and lab experiments, to process-based measurements and experiments over the entire reef, its adjacent oceanic areas and atmosphere. Resultsfrom four projects are presented to act as the foundation for a conceptual model of biogeophysical processes affecting the reef. These cover: (1) benthic composition mapping; (2) biogeophysical forcing processes; (3) dynamics of benthic composition; and (4) dynamics of geomorphic zonation. (1) Benthic composition and reef structure/bathymetry/rugosity mapping to centimetre scales have been completed on an annual basis for > 10 years using standardised methods to quantify the composition of the reef substrate and benthos. Assessment of the resulting annual data sets, shows distinctive spatial variability in macro-algal and benthic micro-algal cover within and between years, while coral cover changes are longer term, unless linked to disturbance events. These data are critical for calibrating and validating satellite image mapping and models of benthic cover composition and dynamics, and determining input areas for foot-printing of eddy-correlation measurements of coral reef energy and gas fluxes. (2) Biogeophysical processes affected by surface energy and gas exchanges and hydrodynamic forcing by gravity waves and tidal currents have only been measured within past 10 years due to developments in sensor technology. For Heron Reef, several

  4. Foodstuff survey around a major nuclear facility with test of satellite images application

    SciTech Connect

    Twining, S.; Strydom, J.; Rosson, R.; Koffman, L.; Fledderman, P.; Kahn, B.

    2000-05-01

    A foodstuff survey was performed around the Savannah River Site, Aiken, South Carolina. It included a census of buildings and fields within 5 km of the boundary and determination of the locations and amounts of crops grown within 80 km of the Savannah River Site center. Recent information for this region was collected on the amounts of meat, poultry, milk, and eggs produced, of deer hunted, and of sports fish caught. The locations and areas devoted to growing each crop were determined by the usual process of applying county agricultural statistics reported by state agencies. This process was compared to crop analysis of two LANDSAT Thematic Mapper images. For use with environmental radionuclide transfer and radiation dose calculation codes, locations within 80 km were defined for 64 sections by 16 sectors centered on the site and by 16-km distance intervals from 16 km to 80 km. The median areas per section devoted to each of four food crops based on county agricultural statistics were about two-thirds of those based on satellite image analysis. Most locally-raised foodstuff was distributed regionally and not retained locally for consumption.

  5. Survey and documentation of emerging technologies for the satellite power system (SPS)

    SciTech Connect

    Glaser, P.; Chapman, P.

    1981-04-01

    The purpose of this study is to survey emerging technologies and new concepts which may offer advantages over those selected for the SPS Reference System. A brief historical overview of the genesis of the Solar Power Satellite (SPS) concept is presented leading to a discussion of the assumptions and guidelines which were originally established and which led to development of the SPS Reference System design concept. Some of these guidelines are applicable to almost any SPS design, but others could be changed, leading to new and perhaps preferable systems. Moreover, while some of the guidelines are based on solid data, some are little more than arbitrary assumptions which were adopted only to proceed with a concrete point design which then could be assessed in the DOE/NASA Concept Development and Evaluation Program. In order to stimulate new SPS concepts and to facilitate comparative assessment of emerging SPS technologies, one useful approach is to break the overall system into functional parts. The system functions which must be performed by any SPS concept and the interrelations between them are discussed and a systematic framework is presented for assessment of the wide variety of system concepts and subsystem technologies which have been proposed. About 80 alternative SPS technologies are reviewed.

  6. Exoplanet Magnetic Fields and Their Detectability

    NASA Astrophysics Data System (ADS)

    Stanley, S.; Tian, B. Y.; Vilim, R.

    2014-12-01

    The investigation of planetary magnetic fields in our solar system provides a wealth of information on planetary interior structure and dynamics. Satellite magnetic data demonstrates that planetary dynamos can produce a range of magnetic field morphologies and intensities. Numerical dynamo simulations are working towards determining relationships between planetary properties and the resulting magnetic field characteristics. However, with only a handful of planetary dynamos in our solar system, it is challenging to determine specific dependence of magnetic field properties on planetary characteristics. Extrasolar planets therefore provide a unique opportunity by significantly increasing the number of planets for study as well as offering a much larger range of planetary properties to investigate. Although detection of exoplanet magnetic fields is challenging at present, the increasing sophistication of observational tools available to astronomers implies these extrasolar planetary magnetic fields may eventually be detectable. This presentation will discuss potential observational trends for magnetic field strength and morphology for exoplanets based on numerical simulations and interior structure modeling. We will focus on the influence of planetary age, environment, composition and structure.

  7. First Solid Evidence for a Rocky Exoplanet - Mass and density of smallest exoplanet finally measured

    NASA Astrophysics Data System (ADS)

    2009-09-01

    The longest set of HARPS measurements ever made has firmly established the nature of the smallest and fastest-orbiting exoplanet known, CoRoT-7b, revealing its mass as five times that of Earth's. Combined with CoRoT-7b's known radius, which is less than twice that of our terrestrial home, this tells us that the exoplanet's density is quite similar to the Earth's, suggesting a solid, rocky world. The extensive dataset also reveals the presence of another so-called super-Earth in this alien solar system. "This is science at its thrilling and amazing best," says Didier Queloz, leader of the team that made the observations. "We did everything we could to learn what the object discovered by the CoRoT satellite looks like and we found a unique system." In February 2009, the discovery by the CoRoT satellite [1] of a small exoplanet around a rather unremarkable star named TYC 4799-1733-1 was announced one year after its detection and after several months of painstaking measurements with many telescopes on the ground, including several from ESO. The star, now known as CoRoT-7, is located towards the constellation of Monoceros (the Unicorn) at a distance of about 500 light-years. Slightly smaller and cooler than our Sun, CoRoT-7 is also thought to be younger, with an age of about 1.5 billion years. Every 20.4 hours, the planet eclipses a small fraction of the light of the star for a little over one hour by one part in 3000 [2]. This planet, designated CoRoT-7b, is only 2.5 million kilometres away from its host star, or 23 times closer than Mercury is to the Sun. It has a radius that is about 80% greater than the Earth's. The initial set of measurements, however, could not provide the mass of the exoplanet. Such a result requires extremely precise measurements of the velocity of the star, which is pulled a tiny amount by the gravitational tug of the orbiting exoplanet. The problem with CoRoT-7b is that these tiny signals are blurred by stellar activity in the form of

  8. Integration of historical aerial and satellite photos, recent satellite images and geophysical surveys for the knowledge of the ancient Dyrrachium (Durres, Albania)

    NASA Astrophysics Data System (ADS)

    Malfitana, Daniele; Shehi, Eduard; Masini, Nicola; Scardozzi, Giuseppe

    2010-05-01

    The paper presents the preliminary results of an integrated multidiscipliary research project concerning the urban area of the modern Durres (ancient Dyrrachium). Here a joint Italian and Albanian researcher are starting preliminary investigations on the place of an ancient roman villa placed in the urban centre of the modern town. In a initial phase are offering interesting results the use of a rich multitemporal remote sensing data-set, historical aerial photos of 1920s and 1930s, photos of USA spy satellites of 1960s and 1970s (Corona KH-4A and KH-4B), and very high resolution satellite imagery. The historical aerial documentation is very rich and includes aerial photogrammetrich flights of two Italian Institutions: the private company SARA - Società Anonima Rilevamenti Aerofotogrammetrici in Rome (1928) and the IGM - Istituto Geografico Militare (1936, 1937 e 1941), which flew on Durres for purposes of cartographic production and military. These photos offer an image of the city before the urban expansion after the Second World War and in recent decades, progressively documented by satellite images of the 1960s-1970s and recent years. They enable a reconstruction of the ancient topography of the urban area, even with the possibility of detailed analysis, as in the case of the the Roman villa, nowadays buried under a modern garden, but also investigated with a GPR survey, in order to rebuild its plan and contextualize the villa in relation to the urban area of the ancient Dyrrachium.

  9. Detecting Exomoons around Self-luminous Giant Exoplanets through Polarization

    NASA Astrophysics Data System (ADS)

    Sengupta, Sujan; Marley, Mark S.

    2016-06-01

    Many of the directly imaged self-luminous gas-giant exoplanets have been found to have cloudy atmospheres. Scattering of the emergent thermal radiation from these planets by the dust grains in their atmospheres should locally give rise to significant linear polarization of the emitted radiation. However, the observable disk-averaged polarization should be zero if the planet is spherically symmetric. Rotation-induced oblateness may yield a net non-zero disk-averaged polarization if the planets have sufficiently high spin rotation velocity. On the other hand, when a large natural satellite or exomoon transits a planet with a cloudy atmosphere along the line of sight, the asymmetry induced during the transit should give rise to a net non-zero, time-resolved linear polarization signal. The peak amplitude of such time-dependent polarization may be detectable even for slowly rotating exoplanets. Therefore, we suggest that large exomoons around directly imaged self-luminous exoplanets may be detectable through time-resolved imaging polarimetry. Adopting detailed atmospheric models for several values of effective temperature and surface gravity that are appropriate for self-luminous exoplanets, we present the polarization profiles of these objects in the infrared during the transit phase and estimate the peak amplitude of polarization that occurs during the inner contacts of the transit ingress/egress phase. The peak polarization is predicted to range between 0.1% and 0.3% in the infrared.

  10. The LBTI Hunt for Observable Signatures of Terrestrial Systems (HOSTS) Survey: a Key NASA Science Program on the Road to Exoplanet Imaging Missions (SPIE Proceedings 2)

    NASA Technical Reports Server (NTRS)

    Danchi, William C.; Bailey, V.; Defrere, D.; Haniff, C.; Hinz, P.; Kennedy, G.; Mennesson, B.; Millan-Gabet, R.; Rieke, G.; Roberge, Aki; Serabyn, E.; Skemer, A.; Stapelfeldt, K.; Weinberger, A.; Wyatt, M.

    2014-01-01

    Telescope Interferometer (LBTI) will survey nearby stars for faint exozodiacal dust (exozodi). This warm circumstellar dust, analogous to the interplanetary dust found in the vicinity of the Earth in our own system, is produced in comet breakups and asteroid collisions. Emission and or scattered light from the exozodi will be the major source of astrophysical noise for a future space telescope aimed at direct imaging and spectroscopy of terrestrial planets (exo- Earths) around nearby stars. About 20 of nearby field stars have cold dust coming from planetesimals at large distances from the stars (Eiroa et al. 2013, AA, 555, A11; Siercho et al. 2014, ApJ, 785, 33). Much less is known about exozodi; current detection limits for individual stars are at best 500 times our solar system's level (aka. 500 zodi). LBTI-HOSTS will be the first survey capable of measuring exozodi at the 10 zodi level (3). Detections of warm dust will also reveal new information about planetary system architectures and evolution. We will describe the motivation for the survey and progress on target selection, not only the actual stars likely to be observed by such a mission but also those whose observation will enable sensible extrapolations for stars that will not be observed with LBTI. We briefly describe the detection of the debris disk around Crv, which is the first scientific result from the LBTI coming from the commissioning of the instrument in December 2013, shortly after the first time the fringes were stabilized.

  11. A Multi-object Exoplanet Detecting Technique

    NASA Astrophysics Data System (ADS)

    Zhang, K.

    2011-05-01

    Exoplanet exploration is not only a meaningful astronomical action, but also has a close relation with the extra-terrestrial life. High resolution echelle spectrograph is the key instrument for measuring stellar radial velocity (RV). But with higher precision, better environmental stability and higher cost are required. An improved technique of RV means invented by David J. Erskine in 1997, External Dispersed Interferometry (EDI), can increase the RV measuring precision by combining the moderate resolution spectrograph with a fixed-delay Michelson interferometer. LAMOST with large aperture and large field of view is equipped with 16 multi-object low resolution fiber spectrographs. And these spectrographs are capable to work in medium resolution mode (R=5{K}˜10{K}). LAMOST will be one of the most powerful exoplanet detecting systems over the world by introducing EDI technique. The EDI technique is a new technique for developing astronomical instrumentation in China. The operating theory of EDI was generally verified by a feasibility experiment done in 2009. And then a multi-object exoplanet survey system based on LAMOST spectrograph was proposed. According to this project, three important tasks have been done as follows: Firstly, a simulation of EDI operating theory contains the stellar spectrum model, interferometer transmission model, spectrograph mediation model and RV solution model. In order to meet the practical situation, two detecting modes, temporal and spatial phase-stepping methods, are separately simulated. The interference spectrum is analyzed with Fourier transform algorithm and a higher resolution conventional spectrum is resolved. Secondly, an EDI prototype is composed of a multi-object interferometer prototype and the LAMOST spectrograph. Some ideas are used in the design to reduce the effect of central obscuration, for example, modular structure and external/internal adjusting frames. Another feasibility experiment was done at Xinglong Station in

  12. Stable regions around Exoplanets: the search for Exomoons

    NASA Astrophysics Data System (ADS)

    Fernandes Guimaraes, Ana Helena; Moretto Tusnski, Luis Ricardo; Vieira-Neto, Ernesto; Silva Valio, Adriana

    2015-08-01

    There are hundreds of exoplanets which the data are available to a dynamical investigation. We extracted from the data base (exoplanets.org) all planets and candidates which have the necessary data available for the numerical investigation of the orbital stability of a body around a exoplanet in a total of 2749 of those.There is a wealth diversity of exoplanets types and the expectation in find our Earth-living conditions in another planet motivates the search for extra-solar planets, and a satellite around a planet would, in addiction, help to keep a favorable climate.Using the planets class according to PHL@Arecibo, those planets were sorted out in groups. Analyses of density, distance from the primary body, and mass ratios were done beside the suggested classification to fit some no-classified planets into one of the groups.The aim of this work is to derive the upper stability limit (or upper critical orbit) of fictitious direct satellites around exoplanets of any density, or size, orbiting single stars. Our search is for stable regions around the planet, the called S-type orbits. This orbit type determines if there is any chance to exist (or not) bodies around the planets. The investigation is limited to single stars, excluding binaries.We derived such limit purely through numerical simulations. Our proposal involved long-term integration of the circular restricted three bodies problem . Basically, the cut off of the stability zone determined in the previous work by Domingos et al. (2006) were confirmed for any planet type. However, the limitation due the Roche limit of the own satellite showed to be lower. We used this to determined possible size and to adjust orbital range were a third body could orbit the exoplanet.Independently of densities, distance, and sizes of the objects involved, the idea was to delimit where to find celestial bodies in any given system around single stars. Furthermore, we aim to provide tracks to the search for exomoons using

  13. The LBTI hunt for observable signatures of terrestrial systems (HOSTS) survey: a key NASA science program on the road to exoplanet imaging missions

    NASA Astrophysics Data System (ADS)

    Danchi, W.; Bailey, V.; Bryden, G.; Defrere, D.; Haniff, C.; Hinz, P.; Kennedy, G.; Mennesson, G.; Millan-Gabet, R.; Rieke, G.; Roberge, A.; Serabyn, E.; Skemer, A.; Stapelfeldt, K.; Weinberger, A.; Wyatt, M.

    2014-07-01

    The Hunt for Observable Signatures of Terrestrial planetary Systems (HOSTS) program on the Large Binocular Telescope Interferometer (LBTI) will survey nearby stars for faint exozodiacal dust (exozodi). This warm circumstellar dust, analogous to the interplanetary dust found in the vicinity of the Earth in our own system, is produced in comet breakups and asteroid collisions. Emission and/or scattered light from the exozodi will be the major source of astrophysical noise for a future space telescope aimed at direct imaging and spectroscopy of terrestrial planets (exo- Earths) around nearby stars. About 20% of nearby field stars have cold dust coming from planetesimals at large distances from the stars (Eiroa et al. 2013, A&A, 555, A11; Siercho et al. 2014, ApJ, 785, 33). Much less is known about exozodi; current detection limits for individual stars are at best ~ 500 times our solar system's level (aka. 500 zodi). LBTI-HOSTS will be the first survey capable of measuring exozodi at the 10 zodi level (3σ). Detections of warm dust will also reveal new information about planetary system architectures and evolution. We will describe the motivation for the survey and progress on target selection, not only the actual stars likely to be observed by such a mission but also those whose observation will enable sensible extrapolations for stars that will not be observed with LBTI. We briefly describe the detection of the debris disk around η Crv, which is the first scientific result from the LBTI coming from the commissioning of the instrument in December 2013, shortly after the first time the fringes were stabilized.

  14. Density Estimation for Projected Exoplanet Quantities

    NASA Astrophysics Data System (ADS)

    Brown, Robert A.

    2011-05-01

    Exoplanet searches using radial velocity (RV) and microlensing (ML) produce samples of "projected" mass and orbital radius, respectively. We present a new method for estimating the probability density distribution (density) of the unprojected quantity from such samples. For a sample of n data values, the method involves solving n simultaneous linear equations to determine the weights of delta functions for the raw, unsmoothed density of the unprojected quantity that cause the associated cumulative distribution function (CDF) of the projected quantity to exactly reproduce the empirical CDF of the sample at the locations of the n data values. We smooth the raw density using nonparametric kernel density estimation with a normal kernel of bandwidth σ. We calibrate the dependence of σ on n by Monte Carlo experiments performed on samples drawn from a theoretical density, in which the integrated square error is minimized. We scale this calibration to the ranges of real RV samples using the Normal Reference Rule. The resolution and amplitude accuracy of the estimated density improve with n. For typical RV and ML samples, we expect the fractional noise at the PDF peak to be approximately 80 n -log 2. For illustrations, we apply the new method to 67 RV values given a similar treatment by Jorissen et al. in 2001, and to the 308 RV values listed at exoplanets.org on 2010 October 20. In addition to analyzing observational results, our methods can be used to develop measurement requirements—particularly on the minimum sample size n—for future programs, such as the microlensing survey of Earth-like exoplanets recommended by the Astro 2010 committee.

  15. Weighing Rocky Exoplanets with Improved Radial Velocimetry

    NASA Astrophysics Data System (ADS)

    Xuesong Wang, Sharon; Wright, Jason; California Planet Survey Consortium

    2016-01-01

    The synergy between Kepler and the ground-based radial velocity (RV) surveys have made numerous discoveries of small and rocky exoplanets, opening the age of Earth analogs. However, most (29/33) of the RV-detected exoplanets that are smaller than 3 Earth radii do not have their masses constrained to better than 20% - limited by the current RV precision (1-2 m/s). Our work improves the RV precision of the Keck telescope, which is responsible for most of the mass measurements for small Kepler exoplanets. We have discovered and verified, for the first time, two of the dominant terms in Keck's RV systematic error budget: modeling errors (mostly in deconvolution) and telluric contamination. These two terms contribute 1 m/s and 0.6 m/s, respectively, to the RV error budget (RMS in quadrature), and they create spurious signals at periods of one sidereal year and its harmonics with amplitudes of 0.2-1 m/s. Left untreated, these errors can mimic the signals of Earth-like or Super-Earth planets in the Habitable Zone. Removing these errors will bring better precision to ten-year worth of Keck data and better constraints on the masses and compositions of small Kepler planets. As more precise RV instruments coming online, we need advanced data analysis tools to overcome issues like these in order to detect the Earth twin (RV amplitude 8 cm/s). We are developing a new, open-source RV data analysis tool in Python, which uses Bayesian MCMC and Gaussian processes, to fully exploit the hardware improvements brought by new instruments like MINERVA and NASA's WIYN/EPDS.

  16. Methods of practice and guidelines for using survey-grade global navigation satellite systems (GNSS) to establish vertical datum in the United States Geological Survey

    USGS Publications Warehouse

    Rydlund, Paul H.; Densmore, Brenda K.

    2012-01-01

    Geodetic surveys have evolved through the years to the use of survey-grade (centimeter level) global positioning to perpetuate and post-process vertical datum. The U.S. Geological Survey (USGS) uses Global Navigation Satellite Systems (GNSS) technology to monitor natural hazards, ensure geospatial control for climate and land use change, and gather data necessary for investigative studies related to water, the environment, energy, and ecosystems. Vertical datum is fundamental to a variety of these integrated earth sciences. Essentially GNSS surveys provide a three-dimensional position x, y, and z as a function of the North American Datum of 1983 ellipsoid and the most current hybrid geoid model. A GNSS survey may be approached with post-processed positioning for static observations related to a single point or network, or involve real-time corrections to provide positioning "on-the-fly." Field equipment required to facilitate GNSS surveys range from a single receiver, with a power source for static positioning, to an additional receiver or network communicated by radio or cellular for real-time positioning. A real-time approach in its most common form may be described as a roving receiver augmented by a single-base station receiver, known as a single-base real-time (RT) survey. More efficient real-time methods involving a Real-Time Network (RTN) permit the use of only one roving receiver that is augmented to a network of fixed receivers commonly known as Continually Operating Reference Stations (CORS). A post-processed approach in its most common form involves static data collection at a single point. Data are most commonly post-processed through a universally accepted utility maintained by the National Geodetic Survey (NGS), known as the Online Position User Service (OPUS). More complex post-processed methods involve static observations among a network of additional receivers collecting static data at known benchmarks. Both classifications provide users

  17. Undercover Stars Among Exoplanet Candidates

    NASA Astrophysics Data System (ADS)

    2005-03-01

    Very Large Telescope Finds Planet-Sized Transiting Star Summary An international team of astronomers have accurately determined the radius and mass of the smallest core-burning star known until now. The observations were performed in March 2004 with the FLAMES multi-fibre spectrograph on the 8.2-m VLT Kueyen telescope at the ESO Paranal Observatory (Chile). They are part of a large programme aimed at measuring accurate radial velocities for sixty stars for which a temporary brightness "dip" has been detected during the OGLE survey. The astronomers find that the dip seen in the light curve of the star known as OGLE-TR-122 is caused by a very small stellar companion, eclipsing this solar-like star once every 7.3 days. This companion is 96 times heavier than planet Jupiter but only 16% larger. It is the first time that direct observations demonstrate that stars less massive than 1/10th of the solar mass are of nearly the same size as giant planets. This fact will obviously have to be taken into account during the current search for transiting exoplanets. In addition, the observations with the Very Large Telescope have led to the discovery of seven new eclipsing binaries, that harbour stars with masses below one-third the mass of the Sun, a real bonanza for the astronomers. PR Photo 06a/05: Brightness "Dip" and Velocity Variations of OGLE-TR-122. PR Photo 06b/05: Properties of Low-Mass Stars and Planets. PR Photo 06c/05: Comparison Between OGLE-TR-122b, Jupiter and the Sun. The OGLE Survey When a planet happens to pass in front of its parent star (as seen from the Earth), it blocks a small fraction of the star's light from our view [1]. These "planetary transits" are of great interest as they allow astronomers to measure in a unique way the mass and the radius of exoplanets. Several surveys are therefore underway which attempt to find these faint signatures of other worlds. One of these programmes is the OGLE survey which was originally devised to detect microlensing

  18. Outline of the survey on the development of earth observation satellites

    NASA Technical Reports Server (NTRS)

    1977-01-01

    An independent earth observation system with land and sea satellites to be developed by Japan is described. Visible and infrared radiometers, microwave radiometers, microwave scattermeters, synthetic aperture radar, and laser sensors are among the instrumentation discussed. Triaxial attitude control, basic technology common to sea and land observation satellites as well as land data analytical technology developed for U.S. LANDSAT data are reviewed.

  19. Exoplanet Equilibrium Chemistry Calculations

    NASA Astrophysics Data System (ADS)

    Blumenthal, Sarah; Harrington, J.; Bowman, M.; Blecic, J.

    2013-10-01

    Recently, Agundez et al. (2012, A&A 548, A73) used a chemical kinetics code to study a model HD 209458b (equilibrium temperature of 1450 K, assuming full redistribution and 0 albedo). They found that thermochemistry dominates most of the dayside, but that significant compositional gradients may exist across the dayside. We calculate equilibrium-chemistry molecular abundances for several model exoplanets, using NASA's open-source Chemical Equilibrium Abundances code (McBride and Gordon 1996). We vary the degree of radiation redistribution to the dark side, ranging from total redistribution to instantaneous reradiation. Atomically, both the solar abundance multiple and the carbon fraction vary. Planet substellar temperatures range from just above 1200 K, where photochemistry should no longer be important, to those of hot planets (3000 K). We present synthetic abundance images for the key spectroscopic molecules CO, CH4, and H2O for several hot-Jupiter model planets. This work was supported by the NASA Planetary Atmospheres grant NNX12AI69G.

  20. Exoplanet Science with TMT

    NASA Astrophysics Data System (ADS)

    Crossfield, Ian

    2014-07-01

    TMT will have unparalleled capabilities for characterizing the composition of extrasolar planets and their atmospheres, and for probing the complex interplay between planet formation, evolution, and migration. In this plenary talk I will summarize these science cases and discuss their synergy with other observing facilities. High-resolution imaging with IRIS and PFI/SEIT will study young, hot planets in nearby star-forming regions, complementing JWST and WFIRST/AFTA coronagraphic efforts at larger semimajor axes. The same instruments will flesh out planets detected by radial velocity (RV) by measuring the albedos and bolometric radii of old, cold Jovian planets and a few ~300 K super-Earths. Complementing JWST and HST studies of short-period transiting planets, NIRES and IRMS spectroscopy will reveal atmospheric composition, dynamics, and thermal structure for dozens of hot Jupiters and Neptunes; NIRES will also produce 2D global maps and movies of a few exoplanets and dozens of brown dwarfs. HROS high-dispersion spectroscopy will precisely measure the composition of extrasolar planetesimals in polluted white dwarfs, and RV followup will continue to exploit the legacies of Kepler, K2, TESS, and PLATO to measure the masses, orbits, and bulk compositions of Earth analogues. Most exciting of all, TMT may facilitate the next major step in the study of exobiology by allowing the detection of biosignature gases around the closest habitable transiting planets.

  1. Exoplanet Caught on the Move

    NASA Astrophysics Data System (ADS)

    2010-06-01

    For the first time, astronomers have been able to directly follow the motion of an exoplanet as it moves from one side of its host star to the other. The planet has the smallest orbit so far of all directly imaged exoplanets, lying almost as close to its parent star as Saturn is to the Sun. Scientists believe that it may have formed in a similar way to the giant planets in the Solar System. Because the star is so young, this discovery proves that gas giant planets can form within discs in only a few million years, a short time in cosmic terms. Only 12 million years old, or less than three-thousandths of the age of the Sun, Beta Pictoris is 75% more massive than our parent star. It is located about 60 light-years away towards the constellation of Pictor (the Painter) and is one of the best-known examples of a star surrounded by a dusty debris disc [1]. Earlier observations showed a warp of the disc, a secondary inclined disc and comets falling onto the star. "Those were indirect, but tell-tale signs that strongly suggested the presence of a massive planet, and our new observations now definitively prove this," says team leader Anne-Marie Lagrange. "Because the star is so young, our results prove that giant planets can form in discs in time-spans as short as a few million years." Recent observations have shown that discs around young stars disperse within a few million years, and that giant planet formation must occur faster than previously thought. Beta Pictoris is now clear proof that this is indeed possible. The team used the NAOS-CONICA instrument (or NACO [2]), mounted on one of the 8.2-metre Unit Telescopes of ESO's Very Large Telescope (VLT), to study the immediate surroundings of Beta Pictoris in 2003, 2008 and 2009. In 2003 a faint source inside the disc was seen (eso0842), but it was not possible to exclude the remote possibility that it was a background star. In new images taken in 2008 and spring 2009 the source had disappeared! The most recent

  2. THE LICK-CARNEGIE EXOPLANET SURVEY: A 3.1 M{sub +} PLANET IN THE HABITABLE ZONE OF THE NEARBY M3V STAR GLIESE 581

    SciTech Connect

    Vogt, Steven S.; Rivera, E. J.; Haghighipour, N.; Henry, Gregory W.; Williamson, Michael H.

    2010-11-01

    We present 11 years of HIRES precision radial velocities (RVs) of the nearby M3V star Gliese 581, combining our data set of 122 precision RVs with an existing published 4.3-year set of 119 HARPS precision RVs. The velocity set now indicates six companions in Keplerian motion around this star. Differential photometry indicates a likely stellar rotation period of {approx}94 days and reveals no significant periodic variability at any of the Keplerian periods, supporting planetary orbital motion as the cause of all the RV variations. The combined data set strongly confirms the 5.37-day, 12.9-day, 3.15-day, and 67-day planets previously announced by Bonfils et al., Udry et al., and Mayor et al.. The observations also indicate a fifth planet in the system, GJ 581f, a minimum-mass 7.0 M{sub +} planet orbiting in a 0.758 AU orbit of period 433 days, and a sixth planet, GJ 581g, a minimum-mass 3.1 M{sub +} planet orbiting at 0.146 AU with a period of 36.6 days. The estimated equilibrium temperature of GJ 581g is 228 K, placing it squarely in the middle of the habitable zone of the star and offering a very compelling case for a potentially habitable planet around a very nearby star. That a system harboring a potentially habitable planet has been found this nearby, and this soon in the relatively early history of precision RV surveys, indicates that {eta}{sub +}, the fraction of stars with potentially habitable planets, is likely to be substantial. This detection, coupled with statistics of the incompleteness of present-day precision RV surveys for volume-limited samples of stars in the immediate solar neighborhood, suggests that {eta}{sub +} could well be on the order of a few tens of percent. If the local stellar neighborhood is a representative sample of the galaxy as a whole, our Milky Way could be teeming with potentially habitable planets.

  3. Characterization of Kepler Exoplanet Host Stars

    NASA Astrophysics Data System (ADS)

    Howell, Steve B.; Everett, M.; Ciardi, D. R.; Silva, D.; Szkody, P.

    2014-01-01

    Using a sample of 220 Exoplanet host stars in the Kepler field for which spectroscopic properties have been determined, we examine their spatial, physical, and time variable properties. Covering effective temperatures from 4670K to 6400K (K4 to F4) and masses from 0.7 to 1.4 M-sun, this sample represents host stars covering the entire Kepler field of view. The majority of the host stars contain one or more Earth-sized exoplanet and range in log g from 4.0 to 4.7 and [Fe/H] from -02.4 to +0.3. Using Yale-Yonsei isochrone fits and photometric information form the Howell-Everett UBV survey of the Kepler field, we examine a complete set of parameters for these stars including their likely residence in the thin or thick disk of the Galaxy. the variability of this sample, in terms of time sale and amplitude, is examined as well.

  4. Asteroseismology of Exoplanet Host Stars

    NASA Astrophysics Data System (ADS)

    Kayhan, Cenk; Çelik Orhan, Zeynep; Yildiz, Mutlu

    2016-07-01

    Exoplanet studies are one of the most interesting and attractive topics in astrophysics. Besides of ground-based observations, Kepler and CoRoT space missions improved our knowledge by providing unprecedented data of exoplanets and host stars. Precise determination of basic properties of planets depends on how we accurately determine fundamental properties of host stars. Asteroseismology is a powerful tool to study stellar structure and evolution and provides us radius, mass and age of the host stars. In this study, we construct stellar interior models of these stars with the MESA evolution code and compare model frequencies with the oscillation frequencies derived from Kepler data. Then, we obtain fundamental parameters of the host stars. Finally, fundamental parameters of exoplanets are reevaluated.

  5. VizieR Online Data Catalog: Exoplanet Orbit Database (Wright+, 2011)

    NASA Astrophysics Data System (ADS)

    Wright, J. T.; Kakhouri, O.; Marcy, G. W.; Han, E.; Feng, Y.; Johnson, J. A.; Howard, A. W.; Fischer, D. A.; Valenti, J. A.; Anderson, J.; Piskunov, N.

    2013-01-01

    We present a database of well determined orbital parameters of exoplanets, and their host stars' properties. This database comprises spectroscopic orbital elements measured for 427 planets orbiting 363 stars from radial velocity and transit measurements as reported in the literature. We have also compiled fundamental transit parameters, stellar parameters, and the method used for the planets discovery. This Exoplanet Orbit Database includes all planets with robust, well measured orbital parameters reported in peer-reviewed articles. The Database is available in a searcheable, filterable, and sortable form on the Web at http://exoplanets.org through the Exoplanets Data Explorer Table, and the data can be plotted and explored through the Exoplanet Data Explorer Plotter. We use the Data Explorer to generate publication-ready plots giving three examples of the signatures of exoplanet migration and dynamical evolution: We illustrate the character of the apparent correlation between mass and period in exoplanet orbits, the different selection biases between radial velocity and transit surveys, and that the multiplanet systems show a distinct semi-major axis distribution from apparently singleton systems. (2 data files).

  6. A COMPLETE SPECTROSCOPIC SURVEY OF THE MILKY WAY SATELLITE SEGUE 1: THE DARKEST GALAXY

    SciTech Connect

    Simon, Joshua D.; Geha, Marla; Minor, Quinn E.; Martinez, Gregory D.; Bullock, James S. E-mail: marla.geha@yale.edu E-mail: gmartine@uci.edu

    2011-05-20

    We present the results of a comprehensive Keck/DEIMOS spectroscopic survey of the ultra-faint Milky Way satellite galaxy Segue 1. We have obtained velocity measurements for 98.2% of the stars within 67 pc (10', or 2.3 half-light radii) of the center of Segue 1 that have colors and magnitudes consistent with membership, down to a magnitude limit of r = 21.7. Based on photometric, kinematic, and metallicity information, we identify 71 stars as probable Segue 1 members, including some as far out as 87 pc. After correcting for the influence of binary stars using repeated velocity measurements, we determine a velocity dispersion of 3.7{sup +1.4}{sub -1.1} km s{sup -1}. The mass within the half-light radius is 5.8{sup +8.2}{sub -3.1} x 10{sup 5} M{sub sun}. The stellar kinematics of Segue 1 require very high mass-to-light ratios unless the system is far from dynamical equilibrium, even if the period distribution of unresolved binary stars is skewed toward implausibly short periods. With a total luminosity less than that of a single bright red giant and a V-band mass-to-light ratio of 3400 M{sub sun}/L{sub sun}, Segue 1 is the darkest galaxy currently known. We critically re-examine recent claims that Segue 1 is a tidally disrupting star cluster and that kinematic samples are contaminated by the Sagittarius stream. The extremely low metallicities ([Fe/H] < -3) of two Segue 1 stars and the large metallicity spread among the members demonstrate conclusively that Segue 1 is a dwarf galaxy, and we find no evidence in favor of tidal effects. We also show that contamination by the Sagittarius stream has been overestimated. Segue 1 has the highest estimated dark matter density of any known galaxy and will therefore be a prime testing ground for dark matter physics and galaxy formation on small scales.

  7. The science of EChO - Exoplanet Characterisation Obseravtory

    NASA Astrophysics Data System (ADS)

    Tinetti, G.; Drossart, P.; Hartogh, P.; Isaak, K.; Linder, M.; Lovis, C.; Micela, G.; Puig, L.; Ollivier, M.; Ribas, I.; Snellen, I.; Swinyard, B.

    2013-09-01

    It is now accepted that exoplanets are ubiquitous in our Galaxy. The planetary parameters mass, radius and temperature alone do not explain the diversity revealed by current observations. The chemical composition of these planets is needed to trace back their formation history and evolution, as was the case for the Solar System. Pioneering results were obtained through transit spectroscopy with Hubble, Spitzer and groundbased facilities, enabling the detection of a few, most abundant ionic, atomic and molecular species and to constrain the planet's thermal structure. With the arrival of EChO in the coming decade, planetary science will expand beyond the narrow boundaries of our Solar System to encompass our whole Galaxy. EChO will address the following fundamental questions: - Why are exoplanets as they are? - What are the causes for the observed diversity? - Can their formation history be traced back from their current composition and evolution? Spectroscopic observations from the visible to Mid-IR of a large, select sample of exoplanets, will allow us to use the chemical composition as a powerful diagnostic of the history, formation mechanisms and evolution of gaseous and rocky exoplanets. Our strategy is to balance statistical information, obtainable through a chemical survey of a large and diverse sample of objects - as it is traditionally done for stars - with deep, repeated observations of a more restricted, select sample of planets - a strategy that will enable the kind of science that was accomplished for Solar System planets.

  8. High Precision Photometry of Bright Transiting Exoplanet Hosts

    NASA Astrophysics Data System (ADS)

    Wilson, Maurice; Eastman, Jason; Johnson, John A.

    2016-01-01

    Within the past two decades, the successful search for exoplanets and the characterization of their physical properties have shown the immense progress that has been made towards finding planets with characteristics similar to Earth. For most exoplanets with a radius about the size of Earth, evaluating their physical properties, such as the mass, radius and equilibrium temperature, cannot be determined with satisfactory precision. The MINiature Exoplanet Radial Velocity Array (MINERVA) was recently built to obtain spectroscopic and photometric measurements to find, confirm, and characterize Earth-like exoplanets. MINERVA's spectroscopic survey targets the brightest, nearby stars which are well-suited to the array's capabilities, while its primary photometric goal is to search for transits around these bright targets. Typically, it is difficult to find satisfactory comparison stars within a telescope's field of view when the primary target is very bright. This issue is resolved by using one of MINERVA's telescopes to observe the primary bright star while the other telescopes observe a distinct field of view that contains satisfactory bright comparison stars. We describe the code used to identify nearby comparison stars, schedule the four telescopes, produce differential photometry from multiple telescopes, and show the first results from this effort.This work has been funded by the Ronald E. McNair Post-Baccalaureate Achievement Program, the ERAU Honors Program, the ERAU Undergraduate Research Spark Fund, and the Banneker Institute at the Harvard-Smithsonian Center for Astrophysics.

  9. Transiting planets with LSST. I. Potential for LSST exoplanet detection

    SciTech Connect

    Lund, Michael B.; Pepper, Joshua; Stassun, Keivan G.

    2015-01-01

    The Large Synoptic Survey Telescope (LSST) is designed to meet several scientific objectives over a 10 year synoptic sky survey. Beyond its primary goals, the large amount of LSST data can be exploited for additional scientific purposes. We show that LSST data are sufficient to detect the transits of exoplanets, including planets orbiting stars that are members of stellar populations that have so far been largely unexplored. Using simulated LSST light curves, we find that existing transit detection algorithms can identify the signatures of Hot Jupiters around solar-type stars, Hot Neptunes around K-dwarfs, and (in favorable cases) Super-Earths in habitable-zone orbits of M-dwarfs. We also find that LSST may identify Hot Jupiters orbiting stars in the Large Magellanic Cloud—a remarkable possibility that would advance exoplanet science into the extragalactic regime.

  10. Remote sensing of effects of land-use practices on water quality. [environmental surveys using Landsat satellites

    NASA Technical Reports Server (NTRS)

    Graves, D. H.

    1975-01-01

    Research efforts are presented for the use of remote sensing in environmental surveys in Kentucky. Ground truth parameters were established that represent the vegetative cover of disturbed and undisturbed watersheds in the Cumberland Plateau of eastern Kentucky. Several water quality parameters were monitored of the watersheds utilized in the establishment of ground truth data. The capabilities of multistage-multispectral aerial photography and satellite imagery were evaluated in detecting various land use practices. The use of photographic signatures of known land use areas utilizing manually-operated spot densitometers was studied. The correlation of imagery signature data to water quality data was examined. Potential water quality predictions were developed from forested and nonforested watersheds based upon the above correlations. The cost effectiveness of predicting water quality values was evaluated using multistage and satellite imagery sampling techniques.