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Sample records for jupiter flyby mission

  1. The New Horizons Mission to Pluto and Flyby of Jupiter

    Science.gov (United States)

    Stern, Alan; Weaver, Hal; Young, Leslie; Bagenal, Fran; Binzel, Richard; Buratti, Bonnie; Cheng, andy; Cruikshank, Dale; Gladstone, Randy; Grundy, Will; Hinson, David; Horanyi, Mihaly; Jennings, Don; Linscott, Ivan; McComas, Dave; McKinnon, William; McNutt, Ralph; Moore, Jeffrey; Murchie, Scott; Olkin, Cathy; Porco, Carolyn; Reitsema, Harold; Reuter, Dennis; Slater, Dave; Spencer, John

    2008-01-01

    New Horizons (NH) is NASA's mission to provide the first in situ reconnaissance of Pluto and its moons Charon, Nix, and Hydra. The NH spacecraft will reach Pluto in July 2015 and will then, if approved for an extended mission phase, continue on to a flyby encounter with one or more Kuiper belt objects (KBOs). NH was launched on 19 January 2006 and received a gravity assist during a flyby encounter with Jupiter (with closest approach at -32 RJ on 28 February 2007) that reduced its flight time to Pluto by 3 years. During the Jupiter flyby, NH collected a trove of multi-wavelength imaging and fields-and-particles measurements. Among the many science results at Jupiter were a detection of planet-wide mesoscale waves, eruptions of atmospheric ammonia clouds, unprecedented views of Io's volcanic plumes and Jupiter's tenuous ring system, a first close-up of the Little Red Spot (LRS), first sightings of polar lightning, and a trip down the tail of the magnetosphere. In 2015, NH will conduct a seven-month investigation of the Pluto system culminating in a closest approach some 12,500 km from Pluto's surface. Planning is presently underway for the Pluto encounter with special emphasis on longidentified science goals of studying the terrain, geology, and composition of the surfaces of Pluto and Charon, examining the composition and structure of Pluto's atmosphere, searching for an atmosphere on Charon, and characterizing Pluto's ionosphere and solar wind interaction. Detailed inspections will also be performed of the newly discovered satellites Nix and Hydra. Additionally, NH will characterize energetic particles in Pluto's environment, refine the bulk properties of Pluto and Charon, and search for additional satellites and rings.

  2. Science of the Europa Multiple Flyby Mission

    Science.gov (United States)

    Pappalardo, Robert T.; Senske, David A.; Prockter, Louise; Hand, Kevin P.; Goldstein, Barry; Europa Science Team

    2016-10-01

    The Europa Multiple Flyby Mission, in formulation for launch in the 2020s, would investigate the habitability of Jupiter's moon Europa. The mission would send a solar-powered, radiation-tolerant spacecraft into an elliptical orbit about Jupiter to conduct more than 40 close flybys of Europa, most in the range 25 km-100 km. The payload comprises a suite of nine science instruments that together would support three key objectives: detailed investigation of Europa's interior, both its internal ocean (including its salinity and depth) and its ice shell (including thickness and potential water pockets within); composition of the icy surface, notably dark reddish areas that may evince linkages between the ocean and the surface; and geology at the regional and local scales, especially areas that may show signs of recent or current activity. The science objectives and project status will be summarized.

  3. Navigational Challenges for a Europa Flyby Mission

    Science.gov (United States)

    Martin-Mur, Tomas J.; Ionasescu, Rodica; Valerino, Powtawche; Criddle, Kevin; Roncoli, Ralph

    2014-01-01

    Jupiter's moon Europa is a prime candidate in the search for present-day habitable environments outside of the Earth. A number of missions have provided increasingly detailed images of the complex surface of Europa, including the Galileo mission, which also carried instruments that allowed for a limited investigation of the environment of Europa. A new mission to Europa is needed to pursue these exciting discoveries using close-up observations with modern instrumentation designed to address the habitability of Europa. In all likelihood the most cost effective way of doing this would be with a spacecraft carrying a comprehensive suite of instruments and performing multiple flybys of Europa. A number of notional trajectory designs have been investigated, utilizing gravity assists from other Galilean moons to decrease the period of the orbit and shape it in order to provide a globally distributed coverage of different regions of Europa. Navigation analyses are being performed on these candidate trajectories to assess the total Delta V that would be needed to complete the mission, to study how accurately the flybys could be executed, and to determine which assumptions most significantly affect the performance of the navigation system.

  4. Tether-mission design for multiple flybys of moon Europa

    Science.gov (United States)

    Sanmartin, J. R. S.; Charro, M. C.; Sanchez-Arriaga, G. S. A.; Sanchez-Torres, A. S. T.

    2015-10-01

    A tether mission to carry out multiple flybys of Jovian moon Europa is here presented. There is general agreement on elliptic-orbit flybys of Europa resulting in cost to attain given scientific goals lower than if actually orbiting the moon, tethers being naturally fit to fly-by rather than orbit moons1. The present mission is similar in this respect to the Clipper mission considered by NASA, the basic difference lying in location of periapsis, due to different emphasis on mission-challenge metrics. Clipper minimizes damaging radiation-dose by avoiding the Jupiter neighborhood and its very harsh environment; periapsis would be at Europa, apoapsis as far as moon Callisto. As in all past outer-planet missions, Clipper faces, however, critical power and propulsion needs. On the other hand, tethers can provide both propulsion and power, but must reach near the planet to find high plasma density and magnetic field values, leading to high induced tether current, and Lorentz drag and power. The bottom line is a strong radiation dose under the very intense Radiation Belts of Jupiter. Mission design focuses on limiting dose. Perijove would be near Jupiter, at about 1.2-1.3 Jovian radius, apojove about moon Ganymede, corresponding to 1:1 resonance with Europa, so as to keep dose down: setting apojove at Europa, for convenient parallel flybys, would require two perijove passes per flyby (the Ganymede apojove, resulting in high eccentricity, about 0.86, is also less requiring on tether operations). Mission is designed to attain reductions in eccentricity per perijove pass as high as Δe ≈ - 0.04. Due the low gravity-gradient, tether spinning is necessary to keep it straight, plasma contactors placed at both ends taking active turns at being cathodic. Efficiency of capture of the incoming S/C by the tether is gauged by the ratio of S/C mass to tether mass; efficiency is higher for higher tape-tether length and lower thickness and perijove. Low tether bowing due to the Lorentz

  5. Orbiter, Flyby and Lander Mission Concepts for Investigating Europa's Habitability

    Science.gov (United States)

    Prockter, L. M.

    2012-04-01

    Coauthors: R. T. Pappalardo (1), F. Bagenal (2), A. C. Barr (3), B. G. Bills (1), D. L. Blaney (1), D. D. Blankenship (4), W. Brinckerhoff (5), J. E. P. Connerney (5), K. Hand (1), T. Hoehler (6), W. Kurth (7), M. McGrath (8), M. Mellon (9), J. M. Moore (6), D. A. Senske (1), E. Shock (10), D. E. Smith (11), T. Gavin (1), G. Garner (1), T. Magner (12), B. C. Cooke (1), R. Crum (1), V. Mallder (12), L. Adams (12), K. Klaasen (1), G. W. Patterson (12), and S. D. Vance (1); 1: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA; 2: University of Colorado, Boulder, CO, USA; 3: Brown University, Providence, RI, USA; 4: University of Texas Institute for Geophysics, Austin, TX, USA; 5: NASA Goddard Space Flight Center, Greenbelt, MD, USA; 6: NASA Ames Research Center, Mountain View, CA, USA; 7: University of Iowa, Iowa City, IA, USA; 8: NASA Marshall Space Flight Center, Huntsville, AL, USA; 9: Southwest Research Institute, Boulder, CO, USA; 10: Arizona State University, Tempe, AZ, USA; 11: Massachusetts Institute of Technology, Cambridge, MA, USA; 12: Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA. Introduction: Assessment of Europa's habitability requires understanding whether the satellite possesses the three "ingredients" for life: water, chemistry, and energy. The National Research Council's Planetary Decadal Survey [1] placed an extremely high priority on Europa science but noted that the budget profile for the Jupiter Europa Orbiter (JEO) mission concept [2] is incompatible with NASA's projected planetary science budget. Thus, in April 2011, NASA enlisted a small Europa Science Definition Team (ESDT) to consider Europa mission options that might be more feasible over the next decade from a programmatic perspective. The ESDT has studied three Europa mission concepts: a Europa orbiter, a Europa multiple-flyby mission, and a Europa lander. These share an overarching goal: Explore Europa to investigate its habitability

  6. RTGs Options for Pluto Fast Flyby Mission

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1993-10-01

    A small spacecraft design for the Pluto Fast Flyby (PFF) Mission is under study by the Jet Propulsion Laboratory (JPL) for the National Aeronautics and Space Administration (NASA), for a possible launch as early as 1998. JPL's 1992 baseline design calls for a power source able to furnish an energy output of 3963 kWh and a power output of 69 watts(e) at the end of the 9.2-year mission. Satisfying those demands is made difficult because NASA management has set a goal of reducing the spacecraft mass from a baseline value of 166 kg to ~110 kg, which implies a mass goal of less than 10 kg for the power source. To support the ongoing NASA/JPL studies, the Department of Energy's Office of Special Applications (DOE/OSA) commissioned Fairchild Space to prepare and analyze conceptual designs of radioisotope power systems for the PFF mission. Thus far, a total of eight options employing essentially the same radioisotope heat source modules were designed and subjected to thermal, electrical, structural, and mass analyses by Fairchild. Five of these - employing thermoelectric converters - are described in the present paper, and three - employing free-piston Stirling converters - are described in the companion paper presented next. The system masses of the thermoelectric options ranged from 19.3 kg to 10.2 kg. In general, the options requiring least development are the heaviest, and the lighter options require more development with greater programmatic risk. There are four duplicate copies

  7. The Europa Jupiter System Mission

    Science.gov (United States)

    Hendrix, A. R.; Clark, K.; Erd, C.; Pappalardo, R.; Greeley, R. R.; Blanc, M.; Lebreton, J.; van Houten, T.

    2009-05-01

    Europa Jupiter System Mission (EJSM) will be an international mission that will achieve Decadal Survey and Cosmic Vision goals. NASA and ESA have concluded a joint study of a mission to Europa, Ganymede and the Jupiter system with orbiters developed by NASA and ESA; contributions by JAXA are also possible. The baseline EJSM architecture consists of two primary elements operating in the Jovian system: the NASA-led Jupiter Europa Orbiter (JEO), and the ESA-led Jupiter Ganymede Orbiter (JGO). The JEO mission has been selected by NASA as the next Flagship mission to the out solar system. JEO and JGO would execute an intricately choreographed exploration of the Jupiter System before settling into orbit around Europa and Ganymede, respectively. JEO and JGO would carry eleven and ten complementary instruments, respectively, to monitor dynamic phenomena (such as Io's volcanoes and Jupiter's atmosphere), map the Jovian magnetosphere and its interactions with the Galilean satellites, and characterize water oceans beneath the ice shells of Europa and Ganymede. EJSM will fully addresses high priority science objectives identified by the National Research Council's (NRC's) Decadal Survey and ESA's Cosmic Vision for exploration of the outer solar system. The Decadal Survey recommended a Europa Orbiter as the highest priority outer planet flagship mission and also identified Ganymede as a highly desirable mission target. EJSM would uniquely address several of the central themes of ESA's Cosmic Vision Programme, through its in-depth exploration of the Jupiter system and its evolution from origin to habitability. EJSM will investigate the potential habitability of the active ocean-bearing moons Europa and Ganymede, detailing the geophysical, compositional, geological and external processes that affect these icy worlds. EJSM would also explore Io and Callisto, Jupiter's atmosphere, and the Jovian magnetosphere. By understanding the Jupiter system and unraveling its history, the

  8. The Jupiter Ganymede Orbiter : An ESA Contribution to the Europa-Jupiter System Mission

    Science.gov (United States)

    Drossart, Pierre; Blanc, M.; Lebreton, J. P.; Pappalardo, R. T.; Greeley, R.; Fujimoto, M.; EJSM/Jupiter Science Definition Team

    2008-09-01

    In the framework of an outer planets mission, under study after the NASA-Juno mission, the Europa-Jupiter System Mission (EJSM) would combine a fleet of up to three satellites in order to investigate in depth many questions related to the Jupiter System. These investigations are essential for our understanding of the emergence and evolution of habitable worlds, not only within the Solar System, but also for extrasolar planets investigations. Scientific targets of EJSM will focus on Europa and Ganymede as a key pair of Galilean satellites, to address the questions on their habitability, formation, and internal structure, as well as the coupling with the whole Jovian system : Jupiter's atmosphere and interior, magnetosphere and magnetodisk. .In combination with a Jupiter Europa Orbiter (JEO likely provided by NASA) and a Jupiter Magnetospheric Orbiter (JMO likely provided by JAXA), ESA is studying a Jupiter Ganymede Orbiter (JGO). The mission scenario includes a direct launch in 2020 with a transfer time to Jupiter of 6 years. After the orbit insertion around Jupiter, a first phase ( 2 years) will be devoted to Jupiter system and Callisto studies, with multiple flybys of Callisto planned at low altitude ( 200 km), followed by a Ganymede orbit insertion and extensive study of Ganymede ( 1 year). In-depth comparative study of inner (Io and Europa) and outer (Ganymede and Callisto) satellites with combined payload of JEO and JGO will address the question of the relative geological evolution of the satellites. On JGO, the transport phenomena in the magnetosphere of Jupiter will be studied in combination with JMO, and the Ganymede magnetosphere will be observed in situ. Jupiter atmosphere investigations on JGO will focus on coupling phenomena between troposphere, stratosphere and mesosphere, the stratospheric composition and the question of thermospheric heating.

  9. PFERD Mission: Pluto Flyby Exploration/Research Design

    Science.gov (United States)

    Lemke, Gary; Zayed, Husni; Herring, Jason; Fuehne, Doug; Sutton, Kevin; Sharkey, Mike

    1990-01-01

    The Pluto Flyby Exploration/Research Design (PFERD) mission will consist of a flyby spacecraft to Pluto and its satellite, Charon. The mission lifetime is expected to be 18 years. The Titan 4 with a Centaur upper stage will be utilized to launch the craft into the transfer orbit. The proposal was divided into six main subsystems: (1) scientific instrumentation; (2) command, communications, and control: (3) altitude and articulation control; (4) power and propulsion; (5) structures and thermal control; and (6) mission management and costing. Tradeoff studies were performed to optimize all factors of design, including survivability, performance, cost, and weight. Problems encountered in the design are also presented.

  10. Jupiter's Phase Variations from Cassini: a testbed for future direct-imaging missions

    Science.gov (United States)

    Mayorga, Laura; Jackiewicz, Jason; Rages, Kathy; West, Robert A.; Knowles, Ben; Lewis, Nikole K.; Marley, Mark S.

    2017-01-01

    Phase curves are important for our understanding of the energy balance and scattering behavior of an exoplanet's atmosphere. In preparation for future direct-imaging missions of Jupiter-like planets, in particular WFIRST, we present phase curves of Jupiter from 0--150 degrees as measured in multiple optical bandpasses by Cassini/ISS during the Millennium flyby of Jupiter in late 2000 to early 2001. We demonstrate and confirm that Jupiter is not well represented by a Lambertian phase function and that its color is more variable with phase angle than predicted by Jupiter-like models. This indicates that a Jupiter-twin observed near quadrature may not be as straightforward to classify as a Jupiter-like planet and comment on the implications for future missions.

  11. Jupiter's Phase Variations from Cassini: a testbed for future direct-imaging missions

    Science.gov (United States)

    Mayorga, Laura; Jackiewicz, Jason; Rages, Kathy; West, Robert; Knowles, Ben; Marley, Mark; Lewis, Nikole

    2016-10-01

    Phase curves are important for our understanding of the energy balance and scattering behavior of an exoplanet's atmosphere. In preparation for future direct-imaging missions of Jupiter-like planets, we present phase curves of Jupiter from 0--150 degrees as measured in multiple optical bandpasses by Cassini/ISS during the Millennium flyby of Jupiter in late 2000 to early 2001. We demonstrate and confirm that Jupiter is not well represented by a Lambertian phase function and that its color is more variable with phase angle than predicted by Jupiter-like models. This indicates that a Jupiter-twin observed near quadrature may not be as straightforward to classify as a Jupiter-like planet.

  12. FIRE - Flyby of Io with Repeat Encounters: A conceptual design for a New Frontiers mission to Io

    Science.gov (United States)

    Suer, Terry-Ann; Padovan, Sebastiano; Whitten, Jennifer L.; Potter, Ross W. K.; Shkolyar, Svetlana; Cable, Morgan; Walker, Catherine; Szalay, Jamey; Parker, Charles; Cumbers, John; Gentry, Diana; Harrison, Tanya; Naidu, Shantanu; Trammell, Harold J.; Reimuller, Jason; Budney, Charles J.; Lowes, Leslie L.

    2017-09-01

    A conceptual design is presented for a low complexity, heritage-based flyby mission to Io, Jupiter's innermost Galilean satellite and the most volcanically active body in the Solar System. The design addresses the 2011 Decadal Survey's recommendation for a New Frontiers class mission to Io and is based upon the result of the June 2012 NASA-JPL Planetary Science Summer School. A science payload is proposed to investigate the link between the structure of Io's interior, its volcanic activity, its surface composition, and its tectonics. A study of Io's atmospheric processes and Io's role in the Jovian magnetosphere is also planned. The instrument suite includes a visible/near-IR imager, a magnetic field and plasma suite, a dust analyzer, and a gimbaled high gain antenna to perform radio science. Payload activity and spacecraft operations would be powered by three Advanced Stirling Radioisotope Generators (ASRG). The primary mission includes 10 flybys with close-encounter altitudes as low as 100 km. The mission risks are mitigated by ensuring that relevant components are radiation tolerant and by using redundancy and flight-proven parts in the design. The spacecraft would be launched on an Atlas V rocket with a delta-v of 1.3 km/s. Three gravity assists (Venus, Earth, Earth) would be used to reach the Jupiter system in a 6-year cruise. The resulting concept demonstrates the rich scientific return of a flyby mission to Io.

  13. Juno at Jupiter: Mission and Science

    Science.gov (United States)

    Bolton, Scott

    2016-07-01

    The Juno mission is the second mission in NASA's New Frontiers program. Launched in August 2011, Juno arrives at Jupiter in July 2016. Juno science goals include the study of Jupiter's origin, interior structure, deep atmosphere, aurora and magnetosphere. Jupiter's formation is fundamental to the evolution of our solar system and to the distribution of volatiles early in the solar system's history. Juno's measurements of the abundance of Oxygen and Nitrogen in Jupiter's atmosphere, and the detailed maps of Jupiter's gravity and magnetic field structure will constrain theories of early planetary development. Juno's orbit around Jupiter is a polar elliptical orbit with perijove approximately 5000 km above the visible cloud tops. The payload consists of a set of microwave antennas for deep sounding, magnetometers, gravity radio science, low and high energy charged particle detectors, electric and magnetic field radio and plasma wave experiment, ultraviolet imaging spectrograph, infrared imager and a visible camera. The Juno design enables the first detailed investigation of Jupiter's interior structure, and deep atmosphere as well as the first in depth exploration of Jupiter's polar magnetosphere. The Juno mission design, science goals, and measurements related to the atmosphere of Jupiter will be presented.

  14. THE JOINT ESA-NASA EUROPA JUPITER SYSTEM MISSION (EJSM)

    Science.gov (United States)

    Lebreton, J.; Pappalardo, R. T.; Blanc, M.; Bunce, E. J.; Dougherty, M. K.; Erd, C.; Grasset, O.; Greeley, R.; Johnson, T. V.; Clark, K. B.; Prockter, L. M.; Senske, D. A.

    2009-12-01

    ) trajectory to reach Jupiter in 2026. After orbit insertion, each would perform a multi-year tour of the Jovian system. The tours would include i) multiple flybys of Io, Europa, Ganymede, and Callisto, ii) continuous magnetospheric monitoring, and iii) regular monitoring of Io and Jupiter’s atmosphere and Jupiter’s ring system. JEO’s Europa orbital phase would start on a circular 200 km altitude around Europa at 90°-100° inclination for about one month before transferring to a 100 km orbit. JGO’s Ganymede orbital phase would start on an elliptical orbit 200 x 10000 km at 86° inclination for about 2-3 months and later transfer to a 200 km circular orbit. JEO would eventually impact Europa and JGO Ganymede, bringing the joint mission to a close.

  15. Radioisotope Thermoelectric Generator Options for Pluto Fast Flyby Mission

    Science.gov (United States)

    Schock, Alfred

    1994-07-01

    A small spacecraft design for the Pluto Fast Flyby (PFF) mission is under study by the Jet Propulsion Laboratory (PL) for the National Aeronautics and Space Administration (NASA), for a possible launch as early as 1998. JPL's 1992 baseline design calls for a power source able to furnish an energy output of 3963 kWh and a power output of 69 Watts(e) at the end of the 9.2-year mission. Satisfying those demands is made difficult because NASA management has set a goal of reducing the spacecraft mass from a baseline value of 166 kg to ~110 kg, which implies a mass goal of less than 10 kg for the power source. To support the ongoing NASA/JPL studies, the Department of Energy's Office of Special Applications (DOE/OSA) commissioned Fairchild Space to prepare and analyze conceptual designs of radioisotope power systems for the PFF mission. Thus far, a total of eight options employing essentially the same radioisotope heat source modules were designed and subjected to thermal, electrical, structural, and mass analyses by Fairchild. Five of these - employing thermoelectric converters - are described in the present paper, and three - employing free-piston Stirling converters - are described in the companion paper presented next. The system masses of the thermoelectric options ranged from 19.3 kg to 10.2 kg. In general, the options requiring least development are the heaviest, and the lighter options require more development with greater programmatic risk.

  16. Radioisotope Stirling Generator Options for Pluto Fast Flyby Mission

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    2012-01-19

    The preceding paper described conceptual designs and analytical results for five Radioisotope Thermoelectric Generator (RTG) options for the Pluto Fast Flyby (PFF) mission, and the present paper describes three Radioisotope Stirling Generator (RSG) options for the same mission. The RSG options are based on essentially the same radioisotope heat source modules used in previously flown RTGs and on designs and analyses of a 75-watt free-piston Stirling engine produced by Mechanical Technology Incorporated (MTI) for NASA's Lewis Research Center. The integrated system design options presented were generated in a Fairchild Space study sponsored by the Department of Energy's Office of Special Applications, in support of ongoing PFF mission and spacecraft studies that the Jet Propulsion Laboratory (JPL) is conducting for the National Aeronautics and Space Administration (NASA). That study's NASA-directed goal is to reduce the spacecraft mass from its baseline value of 166 kg to ~110 kg, which implies a mass goal of less than 10 kg for a power source able to deliver 69 watts(e) at the end of the 9.2-year mission. In general, the Stirling options were found to be lighter than the thermoelectric options described in the preceding paper. But they are less mature, requiring more development, and entailing greater programmatic risk. The Stirling power system mass ranged from 7.3 kg (well below the 10-kg goal) for a non-redundant system to 11.3 kg for a redundant system able to maintain full power if one of its engines fails. In fact, the latter system could deliver as much as 115 watts(e) if desired by the mission planners. There are 2 copies in the file.

  17. Radioisotope Stirling Generator Options for Pluto Fast Flyby Mission

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1993-10-01

    The preceding paper described conceptual designs and analytical results for five Radioisotope Thermoelectric Generator (RTG) options for the Pluto Fast Flyby (PFF) mission, and the present paper describes three Radioisotope Stirling Generator (RSG) options for the same mission. The RSG options are based on essentially the same radioisotope heat source modules used in previously flown RTGs and on designs and analyses of a 75-watt free-piston Stirling engine produced by Mechanical Technology Incorporated (MTI) for NASA's Lewis Research Center. The integrated system design options presented were generated in a Fairchild Space study sponsored by the Department of Energy's Office of Special Applications, in support of ongoing PFF mission and spacecraft studies that the Jet Propulsion Laboratory (JPL) is conducting for the National Aeronautics and Space Administration (NASA). That study's NASA-directed goal is to reduce the spacecraft mass from its baseline value of 166 kg to ~110 kg, which implies a mass goal of less than 10 kg for a power source able to deliver 69 watts(e) at the end of the 9.2-year mission. In general, the Stirling options were found to be lighter than the thermoelectric options described in the preceding paper. But they are less mature, requiring more development, and entailing greater programmatic risk. The Stirling power system mass ranged from 7.3 kg (well below the 10-kg goal) for a non-redundant system to 11.3 kg for a redundant system able to maintain full power if one of its engines fails. In fact, the latter system could deliver as much as 115 watts(e) if desired by the mission planners. There are 5 copies in the file.

  18. The Europa Jupiter System Mission: Synergistic Science Enabled by JEO and JGO

    Science.gov (United States)

    Senske, D. A.; Pappalardo, R. T.; Prockter, L. M.; Lebreton, J.; Greeley, R.; Bunce, E. J.; Dougherty, M. K.; Grasset, O.; Titov, D.

    2010-12-01

    The Europa Jupiter System Mission (EJSM), a joint mission under study by NASA and ESA, has the overarching theme: The emergence of habitable worlds around gas giants. This mission would consist of two major flight elements, the NASA-led Jupiter Europa Orbiter (JEO) and the ESA-led Jupiter Ganymede Orbiter (JGO). The science which could be achieved by EJSM centers around three goals: (1) Explore Europa to investigate its habitability (JEO-focus); (2) Characterize Ganymede as a planetary object including its potential habitability (JGO-focus) and (3) Explore the Jupiter system as an archetype for gas giants (JEO + JGO). The last goal would be addressed primarily during the tour phase of the mission, lasting upwards of 2.5-years, whereby each spacecraft would perform multiple, Galilean satellite fly-bys and make measurements of Jupiter and the Jupiter system. The EJSM Jupiter baseline tour would provide abundant opportunities to perform coordinated Jupiter system science, including fields and particles/magnetometer observations; Jupiter atmosphere monitoring; Io monitoring; spacecraft-to-spacecraft radio occultations of various targets; Galilean satellite flybys; and distant observations of the Galilean moons, small moons, and rings. In realm of understanding the Jovian environment, fields and particles/magnetometer measurements could be carried out nearly continuously, providing unique multipoint measurements of the time-dependent three-dimensional structure of the magnetosphere. In terms of understanding the structure and dynamics of the Jupiter atmosphere, it would be possible to perform coordinated, long-duration (20+ hours), observations over regular periods to monitor weather and understand the behavior of individual storm systems. In a similar manner, regular monitoring of volcanic activity at Io would make it possible to assess the variability in levels of volcanic activity, characterize plume structure, and aid in determining heat flow and transport. Unique

  19. Japanese mission plan for Jupiter system: The Jupiter magnetospheric orbiter and the Trojan asteroid explorer

    Science.gov (United States)

    Sasaki, S.; Fujimoto, M.; Yano, H.; Takashima, T.; Kasaba, Y.; Takahashi, Y.; Kimura, J.; Funase, R.; Mori, O.; Tsuda, Y.; Campagnola, S.; Kawakatsu, Y.

    2011-10-01

    In the future Jupiter system study, Coordinated observation of Jovian magnetosphere is one of the important targets of the mission in addition to icy satellites, atmosphere, and interior of Jupiter. JAXA will take a role on the magnetosphere spinner JMO (Jupiter Magnetospheric Orbiter), in addition to JGO (Jupiter Ganymede Orbiter) by ESA and JEO (Jupiter Europa Orbiter) by NASA. We will combine JMO with a proposed solar sail mission of JAXA for Jupiter and one of Trojan asteroids. Since Trojan asteroids could be representing raw solid materials of Jupiter or at least outer solar system bodies, involvement of Trojan observation should enhance the quality of Jupiter system exploration.

  20. Jupiter's Phase Variations from Cassini: a testbed for future direct-imaging missions

    CERN Document Server

    Mayorga, L C; Rages, K; West, R A; Knowles, B; Lewis, N; Marley, M S

    2016-01-01

    We present phase curves of Jupiter from 0-140 degrees as measured in multiple optical bandpasses by Cassini/ISS during the Millennium flyby of Jupiter in late 2000 to early 2001. Phase curves are of interest for studying the energy balance of Jupiter and understanding the scattering behavior of Jupiter as an exoplanet analog. We find that Jupiter is significantly darker at partial phases than an idealized Lambertian planet by roughly 25% and is not well fit by Jupiter-like exoplanet atmospheric models across all wavelengths. We provide analytic fits to Jupiter's phase function in several Cassini/ISS imaging filter bandpasses. In addition, these observations show that Jupiter's color is more variable with phase angle than predicted by models. Therefore, the color of even a near Jupiter-twin planet observed at a partial phase cannot be assumed to be comparable to that of Jupiter at full phase. We discuss how WFIRST and other future direct-imaging missions can enhance the study of cool giants.

  1. Jupiter Icy Moons Explorer: mission status after the Definition Phase

    Science.gov (United States)

    Titov, Dmitri; Barabash, Stas; Bruzzone, Lorenzo; Dougherty, Michele; Erd, Christian; Fletcher, Leigh; Gare, Philippe; Gladstone, Randall; Grasset, Olivier; Gurvits, Leonid; Hartogh, Paul; Hussmann, Hauke; Iess, Luciano; Jaumann, Ralf; Langevin, Yves; Palumbo, Pasquale; Piccioni, Giuseppe; Sarri, Giuseppe; Wahlund, Jan-Erik; Witasse, Olivier

    2015-04-01

    ultraviolet to the sub-millimetre wavelengths (MAJIS, UVS, SWI). A geophysical package consists of a laser altimeter (GALA) and a radar sounder (RIME) for exploring the surface and subsurface of the moons, and a radio science experiment (3GM) to probe the atmospheres of Jupiter and its satellites and to perform measurements of the gravity fields. An in situ package comprises a powerful particle environment package (PEP), a magnetometer (J-MAG) and a radio and plasma wave instrument (RPWI), including electric fields sensors and a Langmuir probe. An experiment (PRIDE) using ground-based Very-Long-Baseline Interferometry (VLBI) will provide precise determination of the moons ephemerides. The mission scenario will include a Jovian tour with multiple flybys of Callisto and Ganymede, the phase with more than 20 degrees inclination orbits, and two Europa flybys. The Ganymede tour will include high (5000 km) and low (500 km) almost polar orbits around the moon. The mission scenario has evolved slightly during the definition phase, reassuring that the mission will still be able to fulfil all major science objectives. The talk will give an overview of the mission status at the end of the definition phase, focusing on the evolution of science performance and payload synergies in achieving the mission goals.

  2. The EJSM Jupiter-Europa Orbiter: Mission Overview

    Science.gov (United States)

    Pappalardo, R. T.; Clark, K.; Greeley, R.; Hendrix, A. R.; Tan-Wang, G.; Lock, R.; van Houten, T.; Ludwinski, J.; Petropoulis, A.; Jun, I.; Boldt, J.; Kinnison, J.

    2008-09-01

    Missions to explore Europa have been imagined ever since the Voyager mission first suggested that Europa was geologically very young. Subsequently, Galileo supplied fascinating new insights into that satellite's secrets. The Jupiter Europa Orbiter (JEO) would be the NASA-led portion of the Europa Jupiter System Mission (EJSM), an international mission with orbiters developed by NASA, ESA and possibly JAXA. JEO would address key components of the complete EJSM science objectives and would be designed to function alone or in conjunction with the ESA-led Jupiter Ganymede Orbiter and JAXA-led Jupiter Magnetospheric Orbiter. The JEO mission concept uses a single orbiter flight system which would travel to Jupiter to perform a multi-year study of the Jupiter system and Europa, including 2.5-3 years of Jupiter system science and a comprehensive Europa orbit phase of upt ot a year. This abstract describes the design concept of this mission.

  3. Study of Power Options for Jupiter and Outer Planet Missions

    Science.gov (United States)

    Landis, Geoffrey A.; Fincannon, James

    2015-01-01

    Power for missions to Jupiter and beyond presents a challenging goal for photovoltaic power systems, but NASA missions including Juno and the upcoming Europa Clipper mission have shown that it is possible to operate solar arrays at Jupiter. This work analyzes photovoltaic technologies for use in Jupiter and outer planet missions, including both conventional arrays, as well as analyzing the advantages of advanced solar cells, concentrator arrays, and thin film technologies. Index Terms - space exploration, spacecraft solar arrays, solar electric propulsion, photovoltaic cells, concentrator, Fresnel lens, Jupiter missions, outer planets.

  4. Recovery of Europa's geophysical attributes with the radio science component of a Europa Multiple-Flyby Mission

    Science.gov (United States)

    Verma, Ashok Kumar; Margot, Jean-Luc

    2016-10-01

    NASA has approved the development of a multiple-flyby mission to Jupiter's satellite Europa. Important science questions about Europa's interior structure and sub-surface ocean can be addressed by measuring Europa's gravity field, tidal Love number, and spin state. The mission's radio science investigation will rely on tracking the Doppler shift between the spacecraft and Deep Space Network (DSN) antennas. Here, we simulate the X-band two-way coherent Doppler link between the spacecraft and DSN antennas to evaluate the precision with which geophysical parameters can be recovered. We use the project's 15F10 reference trajectory and simulate Doppler measurements within ±2 h of the spacecraft's closest approach to Europa for each one of 42 flybys. After adding noise to the simulated observables, we solve for Europa's GM, degree and order 2 gravity coefficients (J2 and C22), tidal love number k2, pole position (right ascension and declination), and spin rate. The results of our simulations show that the precision in the recovery of geophysical parameters is sufficient to answer questions related to the presence of a global ocean in some tracking scenarios but not in others. We compare our results to an independent analysis by the Europa Mission Gravity Science Working Group (GSWG, 2016).

  5. Ground-based characterization of Eurybates and Orus, two fly-by targets of the Lucy Discovery mission

    Science.gov (United States)

    Mottola, Stefano; Marchi, Simone; Buie, Marc W.; Hellmich, Stephan; Di Martino, Mario; Proffe, Gerrit; Levison, Harold F.; Zangari, Amanda Marie

    2016-10-01

    Lucy is a proposed NASA Discovery mission designed to perform close fly-bys with six Jupiter Trojan asteroids. The mission, which is currently in the Phase A development phase, is planned to launch in 2021 and arrive at the Trojan L4 cloud in 2027.We report on ground-based light curve observations of two of Lucy's fly-by target candidates: (3548) Eurybates and (21900) Orus. The goal is to characterize their shape, spin state and photometric properties both to aid in the planning of the mission, and to complement the space-borne data.Each object has been observed over 5 apparitions in a wide range of geocentric ecliptic longitudes. Shape and spin state modeling was performed by using the convex shape inversion method (Kaasalainen, Mottola & Fulchignoni, 2002). Eurybates is a retrograde rotator with a sidereal rotation Psid=8.702724±0.000009 h. It has a moderately elongated shape with equivalent axial ratios a/b=1.08, b/c=1.16. No obvious signs of global non-convexities and/or albedo variegation are detected in its light curves. Orus is also a retrograde rotator with a period Psid=13.48617±0.00007 h. Its approximate axial ratios are a/b=1.14, b/c=1.12. The presence of a large, planar facet in the proximity of the model's North Pole suggests the presence of a large polar crater.

  6. Design of human missions to Mars and robotic missions to Jupiter

    Science.gov (United States)

    Okutsu, Masataka

    We consider human missions to Mars and robotic missions to Jupiter for launch dates in the near- and far-future. For the near-future, we design trajectories for currently proposed space missions that have well-defined spacecraft and mission requirements. For example, for early human missions to Mars we assume that the constraints used in NASA's design reference missions are indicative of current and near-future technologies, which of course limit our capabilities to explore Mars--and these limits make the problem challenging. Similarly, in the case of robotic exploration of Jupiter, we consider that the technology levels assumed for the proposed Europa Orbiter mission represent reasonable limits. For the far-future (two to three decades from now), we take the best estimates from current literature about the capabilities that may be available in nuclear-powered electric propulsion. We consider hardware capabilities (in terms of specific mass, specific impulse, thrust, power, etc.) for low-thrust trajectories, which range froth near-term to far-future technologies. In designing such missions, several techniques are found useful. For example, the Tisserand Graph, which tracks the changes in orbital shapes and energies, provides insight in designing Jovian tours for the Europa Orbiter mission. The graph is also useful in analyzing abort trajectories for human missions to Mars. Furthermore, a patched-conic propagator, which can generate thousands of potential trajectories, plays a vital role in three of four chapters of this thesis. For launches in the next three decades, we discovered a class of Earth- Mars-Venus-Earth free returns (which appear only four times in the 100-year period), Jovian tours involving ten to twenty flybys of the Galilean satellites, and low-thrust trajectories to Jupiter via gravity assists from Venus, Earth, and Mars. In addition, our continuation method, in which a solution for a conic trajectory is gradually converted into that for a low

  7. A Look Inside the Juno Mission to Jupiter

    Science.gov (United States)

    Grammier, Richard S.

    2008-01-01

    Juno, the second mission within the New Frontiers Program, is a Jupiter polar orbiter mission designed to return high-priority science data that spans across multiple divisions within NASA's Science Mission Directorate. Juno's science objectives, coupled with the natural constraints of a cost-capped, PI-led mission and the harsh environment of Jupiter, have led to a very unique mission and spacecraft design.

  8. Return to Europa: Overview of the Jupiter Europa Orbiter Mission

    Science.gov (United States)

    Clark, K.; Tan-Wang, G.; Boldt, J.; Greeley, R.; Jun, I.; Lock, R.; Ludwinski, J.; Pappalardo, R.; Van Houten, T.; Yan, T.

    2009-01-01

    Missions to explore Europa have been imagined ever since the Voyager mission first suggested that Europa was geologically very young. Subsequently, Galileo supplied fascinating new insights into that satellite's secrets. The Jupiter Europa Orbiter (JEO) would be the NASA-led portion of the Europa Jupiter System Mission (EJSM), an international mission with orbiters developed by NASA, ESA and possibly JAXA. JEO would address a very important subset of the complete EJSM science objectives and is designed to function alone or in conjunction with ESA's Jupiter Ganymede Orbiter (JGO).

  9. MAJIS (Moons and Jupiter Imaging Spectrometer): the VIS-NIR imaging spectrometer of the JUICE mission

    Science.gov (United States)

    Langevin, Yves; Piccioni, Giuseppe; Dumesnil, Cydalise; Filacchione, Gianrico; Poulet, Francois; MAJIS Team

    2016-10-01

    MAJIS is the VIS-NIR imaging spectrometer of JUICE. This ambitious mission of ESA's « cosmic vision » program will investigate Jupiter and its system with a specific focus on Ganymede. After a tour of more than 3 years including 2 fly-bys of Europa and up to 20 flybys of Ganymede and Callisto, the end of the nominal mission will be dedicated to an orbital phase around Ganymede with 120 days in a near-circular, near-polar orbit at an altitude of 5000 km and 130 days in a circular near-polar orbit at an altitude of 500 km. MAJIS will adress 17 of the 19 primary science objectives of JUICE, investigating the surface and exosphere of the Galilean satellites (Ganymede during the orbital phase, Europa and Callisto during close flybys, Io from a minimum distance of 570,000 km), the atmosphere / exosphere of Jupiter, small satellites and rings, and their role as sources and sinks of particles in the Jupiter magnetosphere.The main technical characteristics are the following:Spectral range : 0.5 - 5.7 µm with two overlapping channels (VIS-NIR : 0.5 - 2.35 µm ; IR : 2.25 - 5.7 µm)Spatial resolution : 0.125 to 0.15 mradSpectral sampling (VIS-NIR channel) : 2.9 to 3.45 nmSpectral sampling (IR channel) : 5.4 to 6.45 nmThe spectral and spatial resolution will be finalized in october 2016 after the selection of the MAJIS detectors.Passive cooling will provide operating temperatures noise model will be larger than 100 over most of the spectral range except for high resolution observations of icy moons at low altitude due to limitations on the integration time even with motion compensation provided by a scanner and for exospheric observations due to intrinsic low signal levels.

  10. Multi-Objective Hybrid Optimal Control for Multiple-Flyby Low-Thrust Mission Design

    Science.gov (United States)

    Englander, Jacob A.; Vavrina, Matthew A.; Ghosh, Alexander R.

    2015-01-01

    Preliminary design of low-thrust interplanetary missions is a highly complex process. The mission designer must choose discrete parameters such as the number of flybys, the bodies at which those flybys are performed, and in some cases the final destination. In addition, a time-history of control variables must be chosen that defines the trajectory. There are often many thousands, if not millions, of possible trajectories to be evaluated. The customer who commissions a trajectory design is not usually interested in a point solution, but rather the exploration of the trade space of trajectories between several different objective functions. This can be a very expensive process in terms of the number of human analyst hours required. An automated approach is therefore very desirable. This work presents such an approach by posing the mission design problem as a multi-objective hybrid optimal control problem. The method is demonstrated on a hypothetical mission to the main asteroid belt.

  11. Ground-based characterization of Leucus and Polymele, two fly-by targets of the Lucy Discovery mission

    Science.gov (United States)

    Buie, Marc W.; Zangari, Amanda Marie; Marchi, Simone; Mottola, Stefano; Levison, Harold F.

    2016-10-01

    Lucy is a proposed NASA Discovery mission designed to perform close fly-bys with six Jupiter Trojan asteroids. The mission, which is currently in the Phase A development phase, is planned to launch in 2021 and arrive at the L4 Trojan cloud in 2027. We report on the results of an observational campaign of (11351) Leucus and (15094) Polymele conducted this year. The goal is to characterize their shape, spin state and photometric properties to aid in mission planning and to complement the mission data. Leucus was previously observed by French et al (2013) where they reported a 514 hour rotation period with a lightcurve amplitude as high as 1 magnitude. Our data confirm a long-period and high-amplitude lightcurve but with a period closer to 440 hours. The lightcurve shape has a symmetric double-peaked shape with a ~0.7mag peak-to-peak amplitude. Initial results for Polymele indicate a low-amplitude lightcurve at or below 0.1 mag with a period near 4 hours. Thus, the Lucy target sample includes bodies with among the slowest and fastest rotation rates. Additional observations will be required to further refine the period and pole orientation for both bodies. This year's data are especially challenging due to observing at low galactic latitude. We will report on final results of this year's campaign along with our methods for removing field confusion using optimal image subtraction and photometric calibration based on the new APASS catalog (Henden et al, 2012).

  12. Pioneer Jupiter orbiter probe mission 1980, probe description

    Science.gov (United States)

    Defrees, R. E.

    1974-01-01

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

  13. Science of the Joint ESA-NASA Europa Jupiter System Mission (EJSM)

    Science.gov (United States)

    Blanc, Michel; Greeley, Ron

    2010-05-01

    Jovian satellite system, especially as context for Europa and Ganymede; ii) evaluate the structure and dynamics of the Jovian atmosphere; iii) characterize processes of the Jovian magnetodisk/magnetosphere; iv) determine the interactions occurring in the Jovian system; and v) constrain models for the origin of the Jupiter system. 

 Both spacecraft launch separately in 2020 and use a Venus-Earth-Earth Gravity Assist (VEEGA) trajectory to reach Jupiter in 2026. After orbit insertion, each would perform a multi-year tour of the Jovian system. The tours would include i) multiple flybys of Io, Europa, Ganymede, and Callisto, ii) continuous magnetospheric monitoring, and iii) regular monitoring of Io and Jupiter's atmosphere and Jupiter's ring system. JEO's Europa orbital phase would start on a circular 200 km altitude around Europa at 90°-100° inclination for about one month before transferring to a 100 km orbit. JGO's Ganymede orbital phase would start on an elliptical orbit 200 x 10000 km at 86° inclination for about 2-3 months and later transfer to a 200 km circular orbit. JEO would eventually impact Europa and JGO Ganymede, bringing the joint mission to a close. Operation of two spacecraft in the Jupiter system provides the unparalleled opportunity to address the high-priority questions posed by the NASA Decadal Survey and ESA Cosmic Vision for exploration of the outer solar system. The EJSM mission concept represents a conservative and robust design approach to successfully answering these high-priority questions and making a major step forward in understanding the emergence of habitable worlds around gas giants.

  14. Multi-Objective Hybrid Optimal Control for Multiple-Flyby Interplanetary Mission Design Using Chemical Propulsion

    Science.gov (United States)

    Englander, Jacob; Vavrina, Matthew

    2015-01-01

    The customer (scientist or project manager) most often does not want just one point solution to the mission design problem Instead, an exploration of a multi-objective trade space is required. For a typical main-belt asteroid mission the customer might wish to see the trade-space of: Launch date vs. Flight time vs. Deliverable mass, while varying the destination asteroid, planetary flybys, launch year, etcetera. To address this question we use a multi-objective discrete outer-loop which defines many single objective real-valued inner-loop problems.

  15. Return to Europa: Overview of the Jupiter Europa orbiter mission

    Science.gov (United States)

    Clark, K.; Boldt, J.; Greeley, R.; Hand, K.; Jun, I.; Lock, R.; Pappalardo, R.; van Houten, T.; Yan, T.

    2011-08-01

    Missions to explore Europa have been imagined ever since the Voyager mission first suggested that Europa was geologically very young. Subsequently, the Galileo spacecraft supplied fascinating new insights into this satellite of Jupiter. Now, an international team is proposing a return to the Jupiter system and Europa with the Europa Jupiter System Mission (EJSM). Currently, NASA and ESA are designing two orbiters that would explore the Jovian system and then each would settle into orbit around one of Jupiter's icy satellites, Europa and Ganymede. In addition, the Japanese Aerospace eXploration Agency (JAXA) is considering a Jupiter magnetospheric orbiter and the Russian Space Agency is investigating a Europa lander.The Jupiter Europa Orbiter (JEO) would be the NASA-led portion of the EJSM; JEO would address a very important subset of the complete EJSM science objectives and is designed to function alone or in conjunction with ESA's Jupiter Ganymede Orbiter (JGO). The JEO mission concept uses a single orbiter flight system that would travel to Jupiter by means of a multiple-gravity-assist trajectory and then perform a multi-year study of Europa and the Jupiter system, including 30 months of Jupiter system science and a comprehensive Europa orbit phase of 9 months.The JEO mission would investigate various options for future surface landings. The JEO mission science objectives, as defined by the international EJSM Science Definition Team, include:Europa's ocean: Characterize the extent of the ocean and its relation to the deeper interior.Europa's ice shell: Characterize the ice shell and any subsurface water, including their heterogeneity, and the nature of surface-ice-ocean exchange.Europa's chemistry: Determine global surface compositions and chemistry, especially as related to habitability.Europa's geology: Understand the formation of surface features, including sites of recent or current activity, and identify and characterize candidate sites for future in situ

  16. Global Moon Coverage via Hyperbolic Flybys

    Science.gov (United States)

    Buffington, Brent; Strange, Nathan; Campagnola, Stefano

    2012-01-01

    The scientific desire for global coverage of moons such as Jupiter's Galilean moons or Saturn's Titan has invariably led to the design of orbiter missions. These orbiter missions require a large amount of propellant needed to insert into orbit around such small bodies, and for a given launch vehicle, the additional propellant mass takes away from mass that could otherwise be used for scientific instrumentation on a multiple flyby-only mission. This paper will present methods--expanding upon techniques developed for the design of the Cassini prime and extended missions--to obtain near global moon coverage through multiple flybys. Furthermore we will show with proper instrument suite selection, a flyby-only mission can provide science return similar (and in some cases greater) to that of an orbiter mission.

  17. Early Results from the Juno Mission at Jupiter

    Science.gov (United States)

    Bolton, Scott; Juno Science Team

    2016-10-01

    The Juno mission is the second mission in NASA's New Frontiers program. Launched in August 2011, Juno arrived at Jupiter July 4, 2016. Juno science goals include the study of Jupiter's origin, interior structure, deep atmosphere, aurora and magnetosphere. Juno's orbit around Jupiter is a polar elliptical orbit with perijove approximately 5000 km above the visible cloud tops. The payload consists of a set of microwave antennas for deep sounding, magnetometers, gravity radio science, low and high energy charged particle detectors, electric and magnetic field radio and plasma wave experiment, ultraviolet imaging spectrograph, infrared imager and a visible camera. Early results from the mission will be presented as well as an overview of planned observations.

  18. Radioisotope Thermophotovoltaic (RTPV) Generator and Its Application to the Pluto Fast Flyby Mission

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred; Mukunda, Meera; Or, Chuen T; Kumar, Vasanth; Summers, G.

    1994-01-16

    This paper describes the results of a DOE-sponsored design study of a radioisotope thermophotovoltaic generator. Instead of conducting a generic study, it was decided to focus the design by directing it at a specific space mission, Pluto Fast Flyby (PFF). That mission, under study by JPL, envisages a direct eight-year flight to Pluto (the only unexplored planet in the solar system), followed by comprehensive mapping, surface composition, and atmospheric structure measurements during a brief flyby of the planet and its moon Charon, and transmission of the recorded science data to Earth during a one-year post-encounter cruise. Because of Pluto's long distance from the sun (30-50 A.U.) and the mission's large energy demand, JPL has baselined the use of a radioisotope power system for the PFF spacecraft. The chief advantage of Radioisotope Thermophotovoltaic (RTPV) power systems over current Radioisotope Thermoelectric Generators (RTGs) is their much higher conversion efficiency, which greatly reduces the mass and cost of the required radioisotope heat source. Those attributes are particularly important for the PFF mission, which - like all NASA missions under current consideration - is severely mass- and cost-limited. The paper describes the design of the radioisotope heat source, the thermophotovoltaic converter, and the heat rejection system; and presents the results of the thermal, electrical, and structural analysis and the design optimization of the integrated RTPV system. It briefly summarizes the RTPV system's current technology status, and lists a number of factors that my greatly reduce the need for long-term tests to demonstrate generator lifetime. Our analytical results show very substantial performance improvements over an RTG designed for the same mission, and suggest that the RTPV generator, when developed by DOE and/or NASA, would be quite valuable not only for the PFF mission but also for other future missions requiring small, long

  19. An Alternative Humans to Mars Approach: Reducing Mission Mass with Multiple Mars Flyby Trajectories and Minimal Capability Investments

    Science.gov (United States)

    Whitley, Ryan J.; Jedrey, Richard; Landau, Damon; Ocampo, Cesar

    2015-01-01

    Mars flyby trajectories and Earth return trajectories have the potential to enable lower- cost and sustainable human exploration of Mars. Flyby and return trajectories are true minimum energy paths with low to zero post-Earth departure maneuvers. By emplacing the large crew vehicles required for human transit on these paths, the total fuel cost can be reduced. The traditional full-up repeating Earth-Mars-Earth cycler concept requires significant infrastructure, but a Mars only flyby approach minimizes mission mass and maximizes opportunities to build-up missions in a stepwise manner. In this paper multiple strategies for sending a crew of 4 to Mars orbit and back are examined. With pre-emplaced assets in Mars orbit, a transit habitat and a minimally functional Mars taxi, a complete Mars mission can be accomplished in 3 SLS launches and 2 Mars Flyby's, including Orion. While some years are better than others, ample opportunities exist within a given 15-year Earth-Mars alignment cycle. Building up a mission cadence over time, this approach can translate to Mars surface access. Risk reduction, which is always a concern for human missions, is mitigated by the use of flybys with Earth return (some of which are true free returns) capability.

  20. Telecommunications Antennas for the Juno Mission to Jupiter

    Science.gov (United States)

    Vacchione, Joseph D.; Kruid, Ronald C.; Prata, Aluizio, Jr.; Amaro, Luis R.; Mittskus, Anthony P.

    2012-01-01

    The Juno Mission to Jupiter requires a full sphere of coverage throughout its cruise to and mission at Jupiter. This coverage is accommodated through the use of five (5) antennas; forward facing low gain, medium gain, and high gain antennas, and an aft facing low gain antenna along with an aft mounted low gain antenna with a torus shaped antenna pattern. Three of the antennas (the forward low and medium gain antennas) are classical designs that have been employed on several prior NASA missions. Two of the antennas employ new technology developed to meet the Juno mission requirements. The new technology developed for the low gain with torus shaped radiation pattern represents a significant evolution of the bicone antenna. The high gain antenna employs a specialized surface shaping designed to broaden the antenna's main beam at Ka-band to ease the requirements on the spacecraft's attitude control system.

  1. Telecommunications Antennas for the Juno Mission to Jupiter

    Science.gov (United States)

    Vacchione, Joseph D.; Kruid, Ronald C.; Prata, Aluizio, Jr.; Amaro, Luis R.; Mittskus, Anthony P.

    2012-01-01

    The Juno Mission to Jupiter requires a full sphere of coverage throughout its cruise to and mission at Jupiter. This coverage is accommodated through the use of five (5) antennas; forward facing low gain, medium gain, and high gain antennas, and an aft facing low gain antenna along with an aft mounted low gain antenna with a torus shaped antenna pattern. Three of the antennas (the forward low and medium gain antennas) are classical designs that have been employed on several prior NASA missions. Two of the antennas employ new technology developed to meet the Juno mission requirements. The new technology developed for the low gain with torus shaped radiation pattern represents a significant evolution of the bicone antenna. The high gain antenna employs a specialized surface shaping designed to broaden the antenna's main beam at Ka-band to ease the requirements on the spacecraft's attitude control system.

  2. Jupiter Magnetospheric Orbiter and Trojan Asteroid Explorer in EJSM (Europa Jupiter System Mission)

    Science.gov (United States)

    Sasaki, Sho; Fujimoto, Masaki; Takashima, Takeshi; Yano, Hajime; Kasaba, Yasumasa; Takahashi, Yukihiro; Kimura, Jun; Tsuda, Yuichi; Funase, Ryu; Mori, Osamu

    2010-05-01

    Europa Jupiter System Mission (EJSM) is an international mission to explore and Jupiter, its satellites and magnetospheric environment in 2020s. EJSM consists of (1) The Jupiter Europa Orbiter (JEO) by NASA, (2) the Jupiter Ganymede Orbiter (JGO) by ESA, and (3) the Jupiter Magnetospheric Orbiter (JMO) studied by JAXA (Japan Aerospace Exploration Agency). In February 2009, NASA and ESA decided to continue the study of EJSM as a candidate of the outer solar system mission. JMO will have magnetometers, low-energy plasma spectrometers, medium energy particle detectors, energetic particle detectors, electric field / plasma wave instruments, an ENA imager, an EUV spectrometer, and a dust detector. Collaborating with plasma instruments on board JEO and JGO, JMO will investigate the fast and huge rotating magnetosphere to clarify the energy procurement from Jovian rotation to the magnetosphere, to clarify the interaction between the solar wind the magnetosphere. Especially when JEO and JGO are orbiting around Europa and Ganymede, respectively, JMO will measure the outside condition in the Jovian magnetosphere. JMO will clarify the characteristics of the strongest accelerator in the solar system with the investigation of the role of Io as a source of heavy ions in the magnetosphere. JAXA started a study of a solar power sail for deep space explorations. Together with a solar sail (photon propulsion), it will have very efficient ion engines where electric power is produced solar panels within the sail. JAXA has already experienced ion engine in the successful Hayabusa mission, which was launched in 2003 and is still in operation in 2010. For the purpose of testing solar power sail technology, an engineering mission IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun) will be launched in 2010 together with Venus Climate Orbiter PLANET-C. The shape of the IKAROS' membrane is square, with a diagonal distance of 20m. It is made of polyimide film only 0.0075mm

  3. 木星探测轨道分析与设计%Jupiter Exploration Mission Analysis and Trajectory Design

    Institute of Scientific and Technical Information of China (English)

    陈杨; 宝音贺西; 李俊峰

    2012-01-01

    The trajectory design for Jupiter exploration mission is investigated in this paper. The differences between Jupiter exploration trajectory and Mars or Venus exploration trajectory are mainly concerned about. Firstly, the selection of the Jupiter-centered orbit is analyzed based on the Galileo Jupiter mission. As for the Earth-Jupiter transfer orbit, the fuel consumption of the direct transfer is too large. So the energy-saving technologies such as the planetary gravity assist should be used for the trajectory to the Jupiter. The different sequences of planetary gravity assist for the trajectory from the Earth to the Jupiter are examined by applying the Particle Swarm Optimization (PSO). According to the searching results, Venus-Earth-Earth gravity assist (VEEGA) is the most effective gravity-assist sequence for the Jupiter mission. During the Jupiter mission, the spacecraft will pass though the main asteroid belt which is between the orbits of Mars and Jupiter, and may encounter several asteroids. The Jupiter mission is able to combine with the main-belt asteroid flyby missions. The design method of the intermediate asteroid flyby trajectory is also considered. At last, an entire designed trajectory for the Jupiter mission launched in 2023 is presented.%研究了与木星探测相关的轨道设计问题.重点关注木星探测轨道与火星、金星等类地行星探测轨道的不同及由此带来的轨道设计难点.首先分析了绕木星探测任务轨道的选择.建立近似模型讨论了向木星飞行需要借助多颗行星的多次引力辅助,对地木转移的多种行星引力辅助序列,使用粒子群算法搜索了2020年至2025年之间的燃料最省飞行方案并对比得到了向木星飞行较好的引力辅助方式为金星-地球-地球引力辅助.结合多任务探测,研究了航天器在飞向木星途中穿越主小行星带飞越探测小行星的轨道设计.最后,给出2023年发射完整的结合引力辅助与小行星

  4. Launch Period Development for the Juno Mission to Jupiter

    Science.gov (United States)

    Kowalkowski, Theresa D.; Johannesen, Jennie R.; Lam, Try

    2008-01-01

    The Juno mission to Jupiter is targeted to launch in 2011 and would reach the giant planet about five years later. The interplanetary trajectory is planned to include two large deep space maneuvers and an Earth gravity assist a little more than two years after launch. In this paper, we describe the development of a 21-day launch period for Juno with the objective of keeping overall launch energy and delta-V low while meeting constraints imposed on Earth departure, the deep space maneuvers' timing and geometry, and Jupiter arrival.

  5. Launch Period Development for the Juno Mission to Jupiter

    Science.gov (United States)

    Kowalkowski, Theresa D.; Johannesen, Jennie R.; Lam, Try

    2008-01-01

    The Juno mission to Jupiter is targeted to launch in 2011 and would reach the giant planet about five years later. The interplanetary trajectory is planned to include two large deep space maneuvers and an Earth gravity assist a little more than two years after launch. In this paper, we describe the development of a 21-day launch period for Juno with the objective of keeping overall launch energy and delta-V low while meeting constraints imposed on Earth departure, the deep space maneuvers' timing and geometry, and Jupiter arrival.

  6. Europa Clipper: A Multiple Flyby Mission Concept to Explore Europa's Habitability

    Science.gov (United States)

    Patterson, G. W.; Pappalardo, R. T.; Prockter, L. M.; Senske, D. A.; Vance, S. D.

    2012-09-01

    Europa is a potentially habitable world that is likely to be geologically and chemically active today. Many well-defined and focused science questions regarding past and present habitability may be addressed by exploring Europa. The National Research Council's 2011 Planetary Decadal Survey placed Europa science among its highest priorities, but noted that the budget profile for the Jupiter Europa Orbiter (JEO) mission concept, which was prioritized in the Survey, was incompatible with NASA's projected planetary science budget. Thus, NASA initiated a study to consider more fiscally viable Europa mission scenarios. Among the options considered, a multipleflyby mission concept (now named the "Europa Clipper") was found to have exceptional science merit while also meeting the challenge from NASA and the Decadal Survey for a reduced-scope Europa mission relative to JEO.

  7. Improved orbits of Saturn and Jupiter from the Cassini and Juno missions

    Science.gov (United States)

    Folkner, William M.; Jacobson, Robert Arthur; Jones, Dayton

    2015-08-01

    Since entering orbit about Saturn in 2004, radio tracking data of the Cassini spacecraft has provided accurate measurements of its position leading to marked improvement in the Saturn ephemeris. The Cassini spacecraft orbit period has varied between 14 and 30 days as the orbit was changed to provide views of Saturn’s rings and satellites. This relatively large orbit period has required care to separate the spacecraft orbit relative to Saturn from the orbit of Saturn relative to the Sun. The resulting estimates give a series of range measurements of Saturn relative to Earth with accuracy of ~30 m. In addition to improving the Saturn ephemeris, the range measurements have been used to place stringent upper bounds on possible deviation from General Relativity suggested by the theory of Modified Newtonian Dynamics. The Very Large Baseline Array has been used to observe Cassini and determine the right ascension and declination of Saturn approximately every year since entering orbit. The combination of range and VLBA measurements over more than one-quarter of the Saturn orbit period have resulted in Saturn ephemeris accuracy comparable to that of the inner planets.The Juno spacecraft will enter orbit about Jupiter in July 2016. Juno will be the second spacecraft to orbit Jupiter, but the first to provide a time series of ranging measurements since the Galileo spacecraft high-gain antenna failure prevented range measurements from that mission. Ranging measurements to Juno, combined with VLBA observations, will cover less than one-quarter of an orbit period. But, when combined with the accurate measurements of the Ulysses spacecraft during Jupiter flyby in February 1992, the Jupiter ephemeris accuracy is expected to be close to that of Saturn and the inner planets.

  8. A Post-Stardust Mission View of Jupiter Family Comets

    Science.gov (United States)

    Zolensky, M.

    2011-01-01

    Before the Stardust Mission, many persons (including the mission team) believed that comet nuclei would be geologically boring objects. Most believed that comet nucleus mineralogy would be close or identical to the chondritic interplanetary dust particles (IDPs), or perhaps contain mainly amorphous nebular condensates or that comets might even be composed mainly of preserved presolar material [1]. Amazingly, the results for Comet Wild 2 (a Jupiter class comet) were entirely different. Whether this particular comet will ultimately be shown to be typical or atypical will not be known for a rather long time, so we describe our new view of comets from the rather limited perspective of this single mission.

  9. Pluto Revealed: First Results from the Historic 1st Fly-By Space Mission

    Science.gov (United States)

    Smith, Kimberly Ennico

    2015-01-01

    On July 14, 2015, after a 9.5 year trek across the solar system, NASAs New Horizons spacecraft successfully flew by the dwarf planet Pluto and its system of moons, taking imagery, spectra and in-situ particle data. Data obtained by New Horizons will address numerous outstanding questions on the geology and composition of Pluto and Charon, plus measurements of Plutos atmosphere, and provide revised understanding of the formation and evolution of Pluto and Charon and its smaller moons. This data set is an invaluable glimpse into the outer Third Zone of the Solar System. Data from the intense July 14th fly-by sequence will be downlinked to Earth over a period of 16 months, the duration set by the large data set (over 60 GBits), tempered by limited transmission bandwidth rates (1-2 kbps) and sharing the three 70m DSN assets. This presentation summarizes the New Horizons mission and early science results.

  10. Jupiter

    CERN Document Server

    Penne, Barbra

    2017-01-01

    Our solar system's largest planet is huge enough that all of the system's other planets could fit inside it. Although Jupiter has been known since ancient times, scientists are still learning exciting new information about the planet and its satellites today. In fact, several of its moons are now believed to have oceans below their icy surfaces. Chapters focus on topics such as Jupiter's orbit and rotation, rings, atmosphere, and moons, as well as on the space missions that have helped us get a closer look at the planet and its moons over the past decades.

  11. The Jupiter Ganymede Orbiter mission and spacecraft architecture

    Science.gov (United States)

    Boulade, Sebastien; Maliet, Eric; Saks, Noah; Lang, Rainer; Kemble, Steve

    2010-05-01

    The Europa Jupiter System Mission (EJSM) is a joint NASA-ESA mission candidate, featuring two planetary orbiters in Jovian environment. It will study Jupiter and its magnetosphere, the diversity of the Galilean satellites, the physical characteristics, composition and geology of their surfaces, with a resolution and coverage far beyond what was achieved by Galileo. It will determine their internal structure and the existence of subsurface oceans. It will study the Laplace resonance and its role in maintaining tidal heating. Constraints for the habitability of Europa over geologic timescales will be inferred from monitoring Io and Europa in the visible and infrared combined with precise determination of the satellites' orbital positions. To meet these science objectives, the EJSM mission will optimize the role of each platform. NASA-supplied Jupiter Europa Orbiter (JEO) will focus on the two "rocky" inner Galilean satellites, Io and Europa. Following a similar approach, ESA-procured Jupiter Ganymede Orbiter (JGO) will focus on the two "icy" outer Galilean satellites, Ganymede and Callisto. With these two orbiters around Europa and Ganymede, it will be possible to perform an in-depth comparison, to understand the origin of their geophysical dichotomy and to better understand the unique characteristics of Europa which may make it habitable. Coordination of observations between JEO and JGO could also bring important synergistic science. As part of this EJSM mission, the JGO spacecraft is now one of the candidates for the "L1" launch slot in the ESA Cosmic Vision 2015/2025 plan, with a foreseen launch in 2020. All studies candidate for this L mission concepts currently undergo parallel assessment studies until end of 2010, when two mission concepts will be selected for definition studies, until 2012. Eventually, the first L mission will be selected for industrial implementation starting in 2013. The mission scenario for JGO is based on a launch in 2020 with Ariane 5

  12. Exploration of the Jovian System by EJSM (Europa Jupiter System Mission): Origin of Jupiter and Evolution of Satellites

    Science.gov (United States)

    Sasaki, Sho; Fujimoto, Masaki; Takashima, Takeshi; Yano, Hajime; Kasaba, Yasumasa; Takahashi, Yukihiro; Kimura, Jun; Okada, Tatsuaki; Kawakatsu, Yasuhiro; Tsuda, Yuichi; Kawaguchi, Jun-Ichiro; Funase, Ryu; Mori, Osamu; Morimoto, Mutsuko; Ikoma, Masahiro; Naganuma, Takeshi; Yamaji, Atsushi; Hussmann, Hauke; Kurita, Kei; Working Group, Jupiter

    EJSM (Europa Jupiter System Mission) is a planned Jovian system mission with three spacecraft aiming at coordinated observations of the Jovian satellites especially Europa and the magnetosphere, atmosphere and interior of Jupiter. It was formerly called "Laplace" mission. In October 2007, it was selected as one of future ESA scientific missions Cosmic Vision (2015-2025). From the beginning, Japanese group is participating in the discussion process of the mission. JAXA will take a role on the magnetosphere spinner JMO (Jupiter Magnetosphere Orbiter). On the other hand, ESA will take charge of JGO (Jupiter Ganymede Orbiter) and NASA will be responsible for JEO (Jupiter Europa Orbiter). In February 2009, EJSM is prioritized as the first candidate of outer planet flagship mission and mission study continues in the course of Cosmic Vision. The expected launch time of EJSM will be expected in 2020. Currently we are seeking a possibility to combine JMO with a proposed solar sail mission of JAXA for Jupiter and one of Trojan asteroids.

  13. The Double Flybys of the Cassini Mission: Navigation Challenges and Lessons Learned

    Science.gov (United States)

    Wagner, Sean; Buffington, Brent

    2014-01-01

    Since 2004, the Cassini spacecraft has flown by Titan and other Saturn moons numerous times, successfully accomplishing its 100th targeted encounter of Titan in March 2014. The navigation of Cassini is challenging, even more so with "double flybys," two encounters separated by at most a few days. Because of this tight spacing, there is not enough time for a maneuver in between. Additionally, maneuvers prior to a double flyby only target one of the two encounters. This paper discusses the challenges faced by the Cassini Navigation Team with each double flyby, as well as lessons learned during operational support of each dual encounter. The strengths and weaknesses of the targeting strategies considered for each double flyby are also detailed, by comparing downstream ?V costs and changes to the non-targeted flyby conditions.

  14. Dual-telescope multi-channel thermal-infrared radiometer for outer planet fly-by missions

    Science.gov (United States)

    Aslam, Shahid; Amato, Michael; Bowles, Neil; Calcutt, Simon; Hewagama, Tilak; Howard, Joseph; Howett, Carly; Hsieh, Wen-Ting; Hurford, Terry; Hurley, Jane; Irwin, Patrick; Jennings, Donald E.; Kessler, Ernst; Lakew, Brook; Loeffler, Mark; Mellon, Michael; Nicoletti, Anthony; Nixon, Conor A.; Putzig, Nathaniel; Quilligan, Gerard; Rathbun, Julie; Segura, Marcia; Spencer, John; Spitale, Joseph; West, Garrett

    2016-11-01

    The design of a versatile dual-telescope thermal-infrared radiometer spanning the spectral wavelength range 8-200 μm, in five spectral pass bands, for outer planet fly-by missions is described. The dual-telescope design switches between a narrow-field-of-view and a wide-field-of-view to provide optimal spatial resolution images within a range of spacecraft encounters to the target. The switchable dual-field-of-view system uses an optical configuration based on the axial rotation of a source-select mirror along the optical axis. The optical design, spectral performance, radiometric accuracy, and retrieval estimates of the instrument are discussed. This is followed by an assessment of the surface coverage performance at various spatial resolutions by using the planned NASA Europa Mission 13-F7 fly-by trajectories as a case study.

  15. Europa Habitability and Extant Life Exploration with Combined Flyby-Lander-Orbiter Mission

    Science.gov (United States)

    Blanc, M.; Jones, G.; Prieto-Ballesteros, O.; Mimoun, D.; Masters, A.; Kempf, S.; Iess, L.; Martins, Z.; Lorenz, R.; Lasue, J.; Andre, N.; Bills, B. G.; Choblet, G.; Collins, G.; Cremonese, G.; Garnier, P.; Hand, K.; Hartogh, P.; Khurana, K. K.; Stephan, K.; Tosi, F.; Vance, S. D.; van Hoolst, T.; Westall, F.; Wolwerk, M.; Cooper, J. F.; Sittler, E. C.; Brinckerhoff, W.; Hurford, T.; Europa Initiative

    2016-10-01

    The optimal configuration for investigation of habitability and any extant life at Europa would be a combined constellation of flyby, lander, and orbiter spacecraft. The Europa Initiative is designing a small orbiter as part of this constellation.

  16. JUICE: A European Mission to Jupiter and its Icy Moons

    Science.gov (United States)

    Grasset, Olivier; Witasse, Olivier; Barabash, Stas; Brandt, Pontus; Bruzzone, Lorenzo; Bunce, Emma; Cecconi, Baptiste; Cavalié, Thibault; Cimo, Giuseppe; Coustenis, Athena; Cremonese, Gabriele; Dougherty, Michele; Fletcher, Leigh N.; Gladstone, Randy; Gurvits, Leonid; Hartogh, Paul; Hoffmann, Holger; Hussmann, Hauke; Iess, Luciano; Jaumann, Ralf; Kasaba, Yasumasa; Kaspi, Yohai; Krupp, Norbert; Langevin, Yves; Mueller-Wodarg, Ingo; Palumbo, Pasquale; Piccioni, Giuseppe; Plaut, Jeffrey; Poulet, Francois; Roatsch, Thomas; Retherford, Kurt D.; Rothkaehl, Hanna; Stevenson, David J.; Tosi, Federico; Van Hoolst, Tim; Wahlund, Jan-Erik; Wurz, Peter; Altobelli, Nicolas; Accomazzo, A.; Boutonnet, Arnaud; Erd, Christian; Vallat, Claire

    2016-10-01

    JUICE - JUpiter ICy moons Explorer - is the first large mission in the ESA Cosmic Vision programme [1]. The implementation phase started in July 2015. JUICE will arrive at Jupiter in October 2029, and will spend 3 years characterizing the Jovian system, the planet itself, its giant magnetosphere, and the giant icy moons: Ganymede, Callisto and Europa. JUICE will then orbit Ganymede.The first goal of JUICE is to explore the habitable zone around Jupiter [2]. Ganymede is a high-priority target because it provides a unique laboratory for analyzing the nature, evolution and habitability of icy worlds, including the characteristics of subsurface oceans, and because it possesses unique magnetic fields and plasma interactions with the environment. On Europa, the focus will be on recently active zones, where the composition, surface and subsurface features (including putative water reservoirs) will be characterized. Callisto will be explored as a witness of the early Solar System.JUICE will also explore the Jupiter system as an archetype of gas giants. The circulation, meteorology, chemistry and structure of the Jovian atmosphere will be studied from the cloud tops to the thermosphere and ionosphere. JUICE will investigate the 3D properties of the magnetodisc, and study the coupling processes within the magnetosphere, ionosphere and thermosphere. The mission also focuses on characterizing the processes that influence surface and space environments of the moons.The payload consists of 10 instruments plus a ground-based experiment (PRIDE) to better constrain the S/C position. A remote sensing package includes imaging (JANUS) and spectral-imaging capabilities from UV to sub-mm wavelengths (UVS, MAJIS, SWI). A geophysical package consists of a laser altimeter (GALA) and a radar sounder (RIME) for exploring the moons, and a radio science experiment (3GM) to probe the atmospheres and to determine the gravity fields. The in situ package comprises a suite to study plasma and

  17. Plans and Combined Operations of the Flight Elements of the Europa Jupiter System Mission (EJSM)

    Science.gov (United States)

    Erd, Christian; Clark, K.; Ejsm System Teams

    2010-05-01

    The Europa Jupiter System Mission (EJSM) is a joint NASA-ESA mission candidate, where ESA would provide the Jupiter Ganymede Orbiter (JGO) and NASA would provide the Jupiter Europa Orbiter (JEO). Both spacecraft are foreseen to be launched in 2020, allowing for a joint exploration of the Jovian system, and the Galilean moons. The planning of the development, implementation and combined science phase will be described in the poster.

  18. A SEP Mission to Jupiter Using the Stretched Lens Array

    Science.gov (United States)

    Brandhorst, Henry W.; Rodiek, Julie A.; Ferguson, Dale C.; O'Neill, Mark J.; Piszczor, Michael F.; Oleson, Steve

    2008-01-01

    As space exploration continues to be a primary focus of NASA, solar electric propulsion (SEP) becomes a forerunner in the mode of transportation to reach other planets in our solar system. Several critical issues emerge as potential barriers to this approach such as reducing solar array radiation damage, operating the array at high voltage (>300 V) for extended times for Hall or ion thrusters, and designing an array that will be resistant to micrometeoroid impacts and the differing environmental conditions as the vehicle travels further into space. It is also of great importance to produce an array that is light weight to preserve payload mass fraction and to do this at a cost that is lower than today's arrays. This paper will describe progress on an array that meets all these requirements and will detail its use in a solar electric mission to Jupiter. From 1998-2001, NASA flew the Deep Space 1 mission that validated the use of ion propulsion for extended space missions. This highly successful two-year mission also used a novel SCARLET solar array that concentrated sunlight eight-fold onto small area solar cells. This array performed flawlessly and within 2% of its projected performance over the entire mission. That design has evolved into the Stretched Lens Array (SLA) shown in figure 1. The primary difference between SCARLET and the SLA is that no additional glass cover is used over the silicone lens. This has led to significant mass, cost and complexity reductions. The module shown in figure 1 is the latest version of the design. This design leads to a specific power exceeding 300 W/kg at voltages exceeding 300 V. In addition, this module has been tested to voltages over 1000 V while under hypervelocity particle impact in a plasma environment with no arcing. Furthermore array segments are under test for corona breakdown that can become a critical issue for long term, high voltage missions.

  19. Current Status of the EJSM Jupiter Europa Orbiter Flagship Mission Design

    Science.gov (United States)

    Clark, K.; Pappalardo, R.; Greeley, R.; Hendrix, A.; Boldt, J.; van Houten, T.; Jun, I.; Lock, R.; Ludwinski, J.; Rasmussen, R.; Tan-Wang, G.

    2008-12-01

    NASA and ESA have embarked on a joint study of a mission to Europa and the Jupiter system with orbiters developed by NASA, ESA, and possibly JAXA. An international Joint Jupiter Science Definition Team (JJSDT) is defining the science content for the Jupiter Europa Orbiter (JEO) mission study run by NASA and for the Jupiter Ganymede Orbiter (JGO) mission study run by ESA. Engineering teams for both missions are working closely with the JJSDT to define mission concepts that optimize science, cost, and risk. The NASA-led JEO mission addresses a scientifically rich subset of the complete EJSM science goals and is designed to stand alone or in conjunction with the ESA-led JGO. This paper focuses on the NASA-led JEO mission and will describe the concept in the context of a standalone mission. An orbital mission to Europa is driven by the desire to investigate an astrobiological archetype for icy satellite habitability, with a putative warm, salty, water ocean with plausible energy sources. Additionally, JEO will explore the Jupiter system to better understand how Europa's possible habitability is related to the formation scenario of the other Jovian satellites. The JEO mission will perform 2.5-3 years of Jupiter system science, including encounters with Io, Ganymede and Callisto, before insertion into orbit around Europa for a comprehensive set of science campaigns lasting for up to one year. This paper will highlight the JEO mission design and implementation concept. The work reported was sponsored by the National Aeronautics and Space Administration.

  20. Probing the Flyby Anomaly with the future STE-QUEST mission

    CERN Document Server

    Páramos, Jorge

    2013-01-01

    In this study, we demonstrate that the flyby anomaly, an unexpected acceleration detected in some of the gravitational assists of the Galileo, NEAR, Cassini and Rosetta spacecraft, could be probed by accurate orbital tracking available in the proposed Space-Time Explorer and Quantum Equivalence Principle Space Test (STE- QUEST); following a recent work, we focus on the similarity between an hyperbolic flyby and the perigee passage in a highly elliptic orbit of the latter, as well as its Global Navigation Satellite System precise orbital determination capabilities.

  1. Understanding of particle acceleration and loss in Jupiter's magnetosphere from Juno mission

    Science.gov (United States)

    Bolton, Scott

    2016-07-01

    Juno is the first Jupiter polar mission. Juno science goals include the study of Jupiter's origin, interior structure, deep atmosphere, aurora and magnetosphere. The payload consists of a set of microwave antennas for deep sounding, magnetometers, gravity radio science, low and high energy charged particle detectors, electric and magnetic field radio and plasma wave experiment, ultraviolet imaging spectrograph, infrared imager and a visible camera. Juno's extensive suite of fields and particle experiments along with the UV and IR imagers will provide the first detailed investigation of Jupiter's polar magnetosphere. The set of six microwave radiometers on Juno provide an unprecedented view of Jupiter's synchrotron emission from inside Jupiter's powerful radiation belts. The Juno mission design, science goals, and measurements related to the magnetosphere and radiation belts of Jupiter will be presented.

  2. Limited variance control in statistical low thrust guidance analysis. [stochastic algorithm for SEP comet Encke flyby mission

    Science.gov (United States)

    Jacobson, R. A.

    1975-01-01

    Difficulties arise in guiding a solar electric propulsion spacecraft due to nongravitational accelerations caused by random fluctuations in the magnitude and direction of the thrust vector. These difficulties may be handled by using a low thrust guidance law based on the linear-quadratic-Gaussian problem of stochastic control theory with a minimum terminal miss performance criterion. Explicit constraints are imposed on the variances of the control parameters, and an algorithm based on the Hilbert space extension of a parameter optimization method is presented for calculation of gains in the guidance law. The terminal navigation of a 1980 flyby mission to the comet Encke is used as an example.

  3. Current Status of the EJSM Jupiter Europa Orbiter: Mission Design and Architecture

    Science.gov (United States)

    Grunthaner, Paula; Clark, K.; Pappalardo, R.; Greeley, R.; Hendrix, A.; Boldt, J.; Van Houten, T.; Jun, I.; Lock, R.; Ludwinski, J.; Rasmussen, R.; Tan-Wang, G.

    2008-09-01

    NASA and ESA have embarked on a joint study of a mission to Europa and the Jupiter system with orbiters developed by NASA, ESA, and possibly JAXA. An international Jupiter Joint Science Definition Team (JJSDT) is defining the science content for the Europa Orbiter (JEO) mission study run by NASA and for the Jupiter Ganymede Orbiter (JGO) mission study run by ESA. Engineering teams for both missions are working closely with the JJSDT to define mission concepts that optimize science, cost, and risk. The NASA-led JEO mission addresses a scientifically rich subset of the complete EJSM science goals and is designed to stand alone or in conjunction with the ESA-led JGO. This paper focuses on the NASA-led JEO mission and will describe the concept in the context of a standalone mission. An orbital mission to Europa is driven by the desire to investigate an astrobiological archetype for icy satellite habitability, with a warm, salty, water ocean with plausible energy sources. Additionally, JEO will explore the Jupiter system to better understand how Europa's possible habitability is related to the formation scenario of the other Jovian satellites. The JEO mission will perform 2.5 to 3 years of Jupiter system science, including encounters with Io, Ganymede and Callisto, before insertion into orbit around Europa for a comprehensive set of science campaigns lasting for up to one year. This paper will highlight the JEO mission design and implementation concept. The work reported was sponsored by the National Aeronautics and Space Administration.

  4. Jupiter Icy Moons Explorer (JUICE): Science Objectives, Mission and Instruments (abstract)

    NARCIS (Netherlands)

    Gurvits, L.; Plaut, J.J.; Barabash, S.; Bruzzone, L.; Dougherty, M.; Erd, C.; Fletcher, L.; Gladstone, R.; Grasset, O.; Hartogh, P.; Hussmann, H.; Iess, L.; Jaumann, R.; Langevin, Y.; Palumbo, P.; Piccioni, G...; Titov, D.; Wahlund, J.E.

    2014-01-01

    The JUpiter ICy Moons Explorer (JUICE) is a European Space Agency mission that will fly by and observe the Galilean satellites Europa, Ganymede and Callisto, characterize the Jovian system in a lengthy Jupiter-orbit phase, and ultimately orbit Ganymede for in-depth studies of habitability, evolution

  5. Europa Jupiter System Mission (EJSM): Exploration Of The Jovian System And Its Icy Satellites

    Science.gov (United States)

    Grasset, Olivier; Pappalardo, R.; Greeley, R.; Blanc, M.; Dougherty, M.; Bunce, E.; Lebreton, J.; Prockter, L.; Senske, D.; EJSM Joint Science Definition Team

    2009-09-01

    The Europa Jupiter System Mission (EJSM) would be an international mission with the overall theme of investigating the emergence of habitable worlds around gas giants. Its goals are to (1) Determine whether the Jupiter system harbors habitable worlds and (2) Characterize the processes that are operating within the Jupiter system. NASA and ESA have concluded a detailed joint study of a mission to Europa, Ganymede, and the Jupiter system with orbiters developed by NASA and ESA (future contributions by JAXA and Russia are also possible). The baseline EJSM architecture consists of two primary elements operating in the Jovian system: the NASA-led Jupiter Europa Orbiter (JEO), and the ESA-led Jupiter Ganymede Orbiter (JGO). JEO and JGO would execute an intricately choreographed exploration of the Jupiter System before settling into orbit around Europa and Ganymede, respectively. EJSM would directly address themes concerning the origin and evolution of satellite systems and water-rich environments in icy satellites. The potential habitability of the ocean-bearing moons Europa and Ganymede would be investigated, by characterizing the geophysical, compositional, geological, and external processes that affect these icy worlds. EJSM would also investigate Io and Callisto, Jupiter's atmosphere, and the Jovian magnetosphere. By understanding the Jupiter system and unraveling its history, the formation and evolution of gas giant planets and their satellites would be better known. Most important, EJSM would shed new light on the potential for the emergence of life in the celestial neighborhood and beyond. The EJSM architecture provides opportunities for coordinated synergistic observations by JEO and JGO of the Jupiter and Ganymede magnetospheres, the volcanoes and torus of Io, the atmosphere of Jupiter, and comparative planetology of icy satellites. Each spacecraft would conduct both synergistic dual-spacecraft investigations and "stand-alone” measurements.

  6. Thermo-physical properties of 162173 (1999 JU3), a potential flyby and rendezvous target for interplanetary missions

    CERN Document Server

    Mueller, T G; Hasegawa, S; Abe, M; Kawakami, K; Kasuga, T; Kinoshita, D; Kuroda, D; Urakawa, S; Okumura, S; Sarugaku, Y; Miyasaka, S; Takagi, Y; Weissman, P R; Choi, Y -J; Larson, S; Yanagisawa, K; Nagayama, S

    2010-01-01

    Near-Earth asteroid 162173 (1999 JU3) is a potential flyby and rendezvous target for interplanetary missions because of its easy to reach orbit. The physical and thermal properties of the asteroid are relevant for establishing the scientific mission goals and also important in the context of near-Earth object studies in general. Our goal was to derive key physical parameters such as shape, spin-vector, size, geometric albedo, and surface properties of 162173 (1999 JU3). With three sets of published thermal observations (ground-based N-band, Akari IRC, Spitzer IRS), we applied a thermophysical model to derive the radiometric properties of the asteroid. The calculations were performed for the full range of possible shape and spin-vector solutions derived from the available sample of visual lightcurve observations. The near-Earth asteroid 162173 (1999 JU3) has an effective diameter of 0.87 +/- 0.03 km and a geometric albedo of 0.070 +/- 0.006. The chi2-test reveals a strong preference for a retrograde sense of r...

  7. The mechanical design of an imaging photopolarimeter for the Jupiter missions (Pioneer 10 and 11)

    Science.gov (United States)

    Kodak, J. C.

    1975-01-01

    The mechanical design and fabrication are discussed of the imaging photopolarimeter (IPP), a multifunction space-qualified instrument used on the Jupiter Pioneer missions. The extreme environmental requirements for the structural design, optical system, and mechanisms are described with detailed discussion of some of the design and fabrication problems encountered.

  8. Proton radiation testing of laser optical components for NASA Jupiter Europa Orbiter Mission

    Science.gov (United States)

    Thomes, W. Joe, Jr.; Cavanaugh, John F.; Ott, Melanie N.

    2011-09-01

    The Jupiter Europa Orbiter (JEO) is NASA's element of the joint Europa Jupiter System Mission (EJSM). Based on current trajectories, the spacecraft will spend a significant amount of time in the Jovian radiation belts. Therefore, research endeavors are underway to study the radiation effects on the various parts and components needed to implement the instruments. Data from these studies will be used for component selection and system design to ensure reliable operation throughout the mission duration. The radiation environment en route to Jupiter is nothing new for NASA designed systems, however, the long durations orbiting Jupiter and Europa present new challenges for radiation exposure. High-energy trapped electrons and protons at Jupiter dominate the expected radiation environment. Therefore, most of the initial component level radiation testing is being conducted with proton exposure. In this paper we will present in-situ monitoring of the optical transmission of various laser optical components during proton irradiation. Radiation induced optical attenuation of some components is less than would be expected, based on the authors experiences, and is attributed to the interaction of the protons with the materials. The results are an encouraging first step in screening these optical materials for spaceflight in a high radiation environment.

  9. An Overview of the Jupiter Icy Moons Orbiter (JIMO) Mission, Environments, and Materials Challenges

    Science.gov (United States)

    Edwards, Dave

    2012-01-01

    Congress authorized NASA's Prometheus Project in February 2003, with the first Prometheus mission slated to explore the icy moons of Jupiter with the following main objectives: (1) Develop a nuclear reactor that would provide unprecedented levels of power and show that it could be processed safely and operated reliably in space for long-duration. (2) Explore the three icy moons of Jupiter -- Callisto, Ganymede, and Europa -- and return science data that would meet the scientific goals as set forth in the Decadal Survey Report of the National Academy of Sciences.

  10. Mission Jupiter. Die spektakuläre Reise der Raumsonde Galileo.

    Science.gov (United States)

    Fischer, D.

    Die Raumsonde Galileo ist 1989 gestartet und erforscht seit Dezember 1995 Jupiter und seine Monde. Erstmals ist eine Kapsel mit Meßinstrumenten in dem Gasriesen Jupiter versenkt worden. Die vier großen Jupitermonde wurden von Galileo umfassend erkundet. Seit Dezember 1997 ist die Primärmission abgeschlossen. Der Autor hat das Unternehmen mitverfolgt und schildert detailliert Planung und Ablauf der gesamten Mission. Sein Bericht wird ergänzt durch eine Auswahl der scönsten und wichtigsten Bilder.

  11. Mitigating Extreme Environments for In-Situ Jupiter and Venus Missions

    Science.gov (United States)

    Balint, Tibor S.; Kolawa, Elizabeth A.; Cutts, James A.

    2006-01-01

    In response to the recommendations by the National Research Council (NRC), NASA's Solar System Exploration (SSE) Roadmap identified the in situ exploration of Venus and Jupiter as high priority science objectives. For Jupiter, deep entry probes are recommended, which would descend to approx.250 km - measured from the 1 bar pressure depth. At this level the pressure would correspond to approx.100 bar and the temperature would reach approx.500(deg)C. Similarly, at the surface of Venus the temperature and pressure conditions are approx.460(deg)C and approx.90 bar. Lifetime of the Jupiter probes during descent can be measured in hours, while in{situ operations at and near the surface of Venus are envisioned over weeks or months. In this paper we discuss technologies, which share commonalities in mitigating these extreme conditions over proposed mission lifetimes, specially focusing on pressure and temperature environments.

  12. MESSENGER'S First Flyby of Mercury

    Science.gov (United States)

    Slavin, James A.

    2008-01-01

    The MESSENGER mission to Mercury offers our first opportunity to explore this planet's miniature magnetosphere since Mariner 10's brief fly-bys in 1974-5. The magnetosphere of Mercury is the smallest in the solar system with its magnetic field typically standing off the solar wind only - 1000 to 2000 km above the surface. An overview of the MESSENGER mission and its January 14th close flyby of Mercury will be provided. Primary science objectives and the science instrumentation will be described. Initial results from MESSENGER'S first flyby on January 14th, 2008 will be discussed with an emphasis on the magnetic field and charged particle measurements.

  13. JUpiter ICy moons Explorer (JUICE): An ESA mission to orbit Ganymede and to characterise the Jupiter system

    OpenAIRE

    Grasset, O.; Dougherty, K; Coustenis, A.; Bunce, J; Erd, C.; Titov, D.; Blanc, M.; Coates, A; Drossart, P.; Fletcher, N; Hussmann, H.; Jaumann, R.; N. Krupp; Lebreton, P; O. Prieto-Ballesteros

    2013-01-01

    Past exploration of Jupiter's diverse satellite system has forever changed our understanding of the unique environments to be found around gas giants, both in our solar system and beyond. The detailed investigation of three of Jupiter's Galilean satellites (Ganymede, Europa, and Callisto), which are believed to harbour subsurface water oceans, is central to elucidating the conditions for habitability of icy worlds in planetary systems in general. The study of the Jupiter system and the possib...

  14. System concepts and enabling technologies for an ESA low-cost mission to Jupiter / Europa

    Science.gov (United States)

    Renard, P.; Koeck, C.; Kemble, Steve; Atzei, Alessandro; Falkner, Peter

    2004-11-01

    The European Space Agency is currently studying the Jovian Minisat Explorer (JME), as part of its Technology Reference Studies (TRS), used for its development plan of technologies enabling future scientific missions. The JME focuses on the exploration of the Jovian system and particularly of Europa. The Jupiter Minisat Orbiter (JMO) study concerns the first mission phase of JME that counts up to three missions using pairs of minisats. The scientific objectives are the investigation of Europa's global topography, the composition of its (sub)surface and the demonstration of existence of a subsurface ocean below its icy crust. The present paper describes the candidate JMO system concept, based on a Europa Orbiter (JEO) supported by a communications relay satellite (JRS), and its associated technology development plan. It summarizes an analysis performed in 2004 jointly by ESA and the EADS-Astrium Company in the frame of an industrial technical assistance to ESA.

  15. Trajectories for a Near Term Mission to the Interstellar Medium

    Science.gov (United States)

    Arora, Nitin; Strange, Nathan; Alkalai, Leon

    2015-01-01

    Trajectories for rapid access to the interstellar medium (ISM) with a Kuiper Belt Object (KBO) flyby, launching between 2022 and 2030, are described. An impulsive-patched-conic broad search algorithm combined with a local optimizer is used for the trajectory computations. Two classes of trajectories, (1) with a powered Jupiter flyby and (2) with a perihelion maneuver, are studied and compared. Planetary flybys combined with leveraging maneuvers reduce launch C3 requirements (by factor of 2 or more) and help satisfy mission-phasing constraints. Low launch C3 combined with leveraging and a perihelion maneuver is found to be enabling for a near-term potential mission to the ISM.

  16. Surface Experiments on a Jupiter Trojan Asteroid in the Solar Powered Sail Mission

    Science.gov (United States)

    Okada, Tatsuaki

    2016-04-01

    Introduction: A new mission to a Jupiter Trojan asteroid is under study us-ing a solar-powered sail (SPS), and a science lander is being investigated in the joint study between Japan and Europe [1]. We present here the key sci-entific objectives and the strawman payloads of science experiments on the asteroid. Science Objectives: Jupiter Trojan asteroids are located around the Sun-Jupiter Lagrange points (L4 or L5) and most of them are classified as D- or P-type in asteroid taxonomy, but their origin still remains unknown. A classi-cal (static) model of solar system evolution indicates that they were formed around the Jupiter region and survived until now as the outer end members of asteroids. A new (dynamical) model such as Nice model suggests that they were formed at the far end of the solar system and transferred inward due to dynamical migration of giant planets [2]. Therefore physical, miner-alogical, and isotopic studies of surface materials and volatile compounds could solve their origin, and then the solar system formation [3]. Strawman Payloads: The SPS orbiter will be able to carry a 100 kg class lander with 20 kg mission payloads. Just after landing of the lander, geolog-ical, mineralogical, and geophysical observations will be performed to char-acterize the site using a panoramic optical camera, an infrared hyperspectral imager, a magnetometer, and a thermal radiometer. The surface and subsur-face materials of the asteroid will be collected into a carousel by the bullet-type and the pneumatic drill type samplers, respectively. Samples in the carousel will be investigated by a visible and an infrared microscope, and transferred for performing high resolution mass spectrometry (HRMS). Mass resolution m/dm > 30,000 is expected to investigate isotopic ratios of D/H, 15N/14N, and 18O/16O, as well as molecules from organic matters. A set of strawman payloads are tentatively determined during the lander system study [4]. The constraints to select the strawman

  17. The EJSM Jupiter-Ganymede Orbiter

    Science.gov (United States)

    Blanc, M.; Lebreton, J.-P.; Stankov, A.; Greeley, R.; Pappalardo, R. T.; Fujimoto, M.

    2008-09-01

    The Europa-Jupiter System Mission (EJSM), currently subject of a joint study by NASA, ESA and JAXA, would combine a fleet of three satellites in order to investigate in depth many questions related to the Jupiter System. These investigations are essential for our understanding of the emergence and evolution of habitable worlds, not only within the Solar System, but also for extrasolar planet investigations. Scientific targets of EJSM focus on Europa and Ganymede as a key pair of Galilean satellites, to address the questions on their habitability, formation, and internal structure, as well as the coupling with the whole Jovian system: Jupiter's atmosphere and interior, magnetosphere and magnetodisk.. In combination with a Jupiter Europa Orbiter (JEO that would be provided by NASA) and a Jupiter Magnetospheric Orbiter (JMO that would be provided by JAXA), ESA is studying a Jupiter Ganymede Orbiter (JGO). The mission scenario includes a launch in 2020 with a transfer time to Jupiter of ~6 years. After the orbit insertion around Jupiter, a first phase (~2 years) will be devoted to Jupiter system and Callisto studies, with multiple flybys of Callisto planned at low altitude (~200 km), followed by a Ganymede orbit insertion and extensive study of Ganymede (~1 year). In depth comparative study of inner (Io and Europe) and outer (Ganymede and Callisto) satellites with combined payload of JEO and JGO will address the question of the geologic relative evolution of the satellites. On JGO, the transport phenomena in the magnetosphere of Jupiter will be studied in combination with JMO, and the Ganymede magnetosphere will be observed in situ. Jupiter atmosphere investigations on JGO will focus on coupling phenomena between troposphere, stratosphere and mesosphere, the stratospheric composition and the question of thermospheric heating.

  18. JIRAM, the image spectrometer in the near infrared on board the Juno mission to Jupiter.

    Science.gov (United States)

    Adriani, Alberto; Coradini, Angioletta; Filacchione, Gianrico; Lunine, Jonathan I; Bini, Alessandro; Pasqui, Claudio; Calamai, Luciano; Colosimo, Fedele; Dinelli, Bianca M; Grassi, Davide; Magni, Gianfranco; Moriconi, Maria L; Orosei, Roberto

    2008-06-01

    The Jovian InfraRed Auroral Mapper (JIRAM) has been accepted by NASA for inclusion in the New Frontiers mission "Juno," which will launch in August 2011. JIRAM will explore the dynamics and the chemistry of Jupiter's auroral regions by high-contrast imaging and spectroscopy. It will also analyze jovian hot spots to determine their vertical structure and infer possible mechanisms for their formation. JIRAM will sound the jovian meteorological layer to map moist convection and determine water abundance and other constituents at depths that correspond to several bars pressure. JIRAM is equipped with a single telescope that accommodates both an infrared camera and a spectrometer to facilitate a large observational flexibility in obtaining simultaneous images in the L and M bands with the spectral radiance over the central zone of the images. Moreover, JIRAM will be able to perform spectral imaging of the planet in the 2.0-5.0 microm interval of wavelengths with a spectral resolution better than 10 nm. Instrument design, modes, and observation strategy will be optimized for operations onboard a spinning satellite in polar orbit around Jupiter. The JIRAM heritage comes from Italian-made, visual-infrared imaging spectrometers dedicated to planetary exploration, such as VIMS-V on Cassini, VIRTIS on Rosetta and Venus Express, and VIR-MS on the Dawn mission.

  19. Probing the Physics and Chemistry in Hot Jupiter Exoclimes for Future Missions

    Science.gov (United States)

    Afrin Badhan, Mahmuda; Kopparapu, Ravi Kumar; Domagal-Goldman, Shawn; Deming, Drake; Hébrard, Eric; Irwin, Patrick GJ; Batalha, Natasha; Mandell, Avi

    2017-01-01

    Unique and exotic planets give us an opportunity to understand how planetary systems form and evolve over their lifetime, by placing our own planetary system in the context of vastly different extrasolar systems. In particular, close-in planets such as Hot Jupiters provide us with valuable insights about the host stellar atmosphere and planetary atmospheres subjected to such high levels of stellar insolation. Observed spectroscopic signatures from a planet reveal all spectrally active species in its atmosphere, along with information about its thermal structure and dynamics, allowing us to characterize the planet's atmosphere. NASA’s upcoming missions will give us the high-resolution spectra necessary to constrain such atmospheric properties with unprecedented accuracy. However, to interpret the observed signals from exoplanetary transit events with any certainty, we need reliable atmospheric modeling tools that map both the physical and chemical processes affecting the particular type of planet under investigation. My work seeks to expand on past efforts in these two categories for irradiated giant exoplanets. These atmospheric models can be combined with future mission simulations to build tools that allow us to self-consistently “retrieve” the signatures we can expect to observe with the instruments. In my work thus far, I have built the robust Markov Chain Monte Carlo convergence scheme, with an analytical radiative equilibrium formulation to represent the thermal structures, within the NEMESIS atmospheric radiative transfer modeling and retrieval tool. I have combined this physics-based thermal structure with photochemical abundance profiles for the major gas atmospheric constituents, using the NASA Astrobiology Institute’s VPL/Atmos photochemistry model, which I recently extended to giant planet regimes. Here I will present my new Hot Jupiter models and retrievals results constructed from these latest enhancements. For comparison, I will show

  20. An independent discovery of two hot Jupiters from the K2 mission

    CERN Document Server

    Brahm, Rafael; Espinoza, Néstor; Jordán, Andrés; Rabus, Markus; Rojas, Felipe; Jenkins, James S; Cortés, Cristián; Drass, Holger; Pantoja, Blake; Soto, Maritza G; Vučković, Maja

    2016-01-01

    We report the discovery of two hot Jupiters using photometry from Campaigns 4 and 5 of the two-wheeled Kepler (K2) mission. EPIC210957318b has a mass of $ 0.65 \\pm 0.14 M_J$, a radius of $1.070 \\pm 0.018 R_J$ and transits its G dwarf ($T_{eff} = 5675 \\pm 50$ K), slightly metal rich ([Fe/H]$=+0.06\\pm0.04$ dex) host star in a 4.1 days circular orbit. EPIC212110888b has a mass of $ 1.63 \\pm 0.12 M_J$, a radius of $1.38 \\pm 0.014 R_J$ and has an orbital period of 3.0 days in which it orbits a late F dwarf ($T_{eff} = 6149 \\pm 55$ K) solar metallicity star. Both planets were validated probabilistically and confirmed via precision radial velocity (RV) measurements. They have physical and orbital properties similar to the ones of the already uncovered population of hot Jupiters and are well-suited candidates for further orbital and atmospheric characterization via detailed follow-up observations.

  1. Jupiter radiation test levels and their expected impact on an encounter mission

    Science.gov (United States)

    Barengoltz, J. B.

    1972-01-01

    The upper limit, of electron and proton fluences for a thermoelectric outer planet spacecraft mission in a near-Jupiter environment, for use as radiation design restraints, were extracted from a model of the Jovian trapped radiation belts. Considerations of radiation effects in semiconductor devices were employed to construct simplified radiation test levels based on the design restraints. Corresponding levels, based on the nominal belt models, are one to three orders of magnitude smaller. In terms of expected radiation-induced degradation in semiconductor devices, an encounter with an environment as severe as the design restraints would require hardening the system in order to guarantee high reliability. On the other hand, the nominal levels would only necessitate care in the selection of components and the avoidance of certain semiconductor components.

  2. A Jupiter Ganymede Orbiter for the EJSM mission: the JGO assessment phase study by the Thales Alenia Space consortium

    Science.gov (United States)

    Poncy, Joel; Couzin, Patrice; Mercier, Manuel; Boschetti, Demis

    2010-05-01

    ESA and NASA have undertaken advanced studies of a common mission to Jupiter's system, EJSM (Europa Jupiter System Mission). This mission comprises two spacecrafts launched independently in 2020 and reaching the system in 2026. This is a one-in-a-generation opportunity for Europe to contribute significantly to the science of this part of the Solar System, and as such, all efforts shall subsequently be made to maximize the scientific return without jeopardizing the technical and programmatic feasibility of the mission. A sub-glacial ocean on Europa and potentially two others on Ganymede and Callisto, the monitoring of Io's volcanic activity, the upper atmosphere of Jupiter, its rings, its tens of irregular moons, the tides, the magnetic fields of Jupiter and Ganymede and the behaviour of the plasma, the list of science objectives is not only impressive but also generates enthusiasm in the mission. In this NASA-ESA joint mission, NASA will take charge of both Io and Europa with the Jupiter Europa Orbiter (JEO). Europe will get a fascinating share with the Jupiter Ganymede Orbiter (JGO), which will achieve the close study of the two largest and outermost Galilean moons Ganymede and Callisto and in addition, at-a-distance, the observation of the other targets mentioned above. ESA has awarded three industrial contracts for an assessment phase of JGO. As leader of one of the consortia, Thales Alenia Space is proud to present in this poster its achievements on this exciting mission. The requirements are discussed and the mission drivers identified. The main trades and the resulting architecture are recalled, along with the main selection drivers. The major system interrelated trades have covered the launcher and propulsion type, the number of regulated phases, the strategy for communications and science timeline, the need for HGA pointing, the sizing and configuration of the Solar Array, the accommodation of external appendages, the accommodation of the payload, the

  3. MIDL: A Demonstration of Multi-Mission Analysis of Charged Particle Data From Van Allen Probes and the Juno Earth Flyby

    Science.gov (United States)

    Brown, L. E.; Mitchell, D. G.; Paranicas, C.; Mauk, B.; Lanzerotti, L. J.; Vandegriff, J. D.

    2013-12-01

    At the present time, a fleet of heliosphere spacecraft is producing an unprecedented number of measurements of charged particles and magnetic fields throughout the solar system - from Mercury to the local interstellar medium. It is vital to have a flexible and efficient data browsing, discovery, and analysis environment to navigate this wealth of information. We present a multi-mission tool for quick look data viewing and analysis. In addition to a rich tool and feature set, MIDL3 (Mission Independent Data Layer - 3rd version) provides environments to cater to different user classes from instrument team engineers, to team scientists, to the general science community. Furthermore, MIDL3 adds a new, highly interactive, end-user visualization environment for rapid browsing and exploration of science and engineering data. Like AMDA and MAPSVIEW, MIDL has functioned for Cassini plasma and particle data as a highly successful platform for inter-comparing different instruments/sensors with minimal preparation work on the part of the user. We present a demonstration of simultaneous analysis of the JUNO Earth flyby (October 9, 2013) data from the JEDI instruments and Van Allen Probes data from the RBSPICE instruments. Since these two instrument sets share a very similar design (see presentations by C Paranicas, et al. and J Manwiler, et al. at this conference for details) we anticipate important results from this unique opportunity to compare measurements of energetic electrons and ions made by six telescopes each for the five similar instruments on three spacecraft within Earth's magnetosphere.

  4. Jupiter System Observer

    Science.gov (United States)

    Senske, Dave; Kwok, Johnny

    2008-01-01

    This slide presentation reviews the proposed mission for the Jupiter System Observer. The presentation also includes overviews of the mission timeline, science goals, and spacecraftspecifications for the satellite.

  5. Disentangling plasma interaction and induction signatures at Callisto: The Galileo C10 flyby

    Science.gov (United States)

    Liuzzo, Lucas; Simon, Sven; Feyerabend, Moritz; Motschmann, Uwe

    2016-09-01

    We apply a combination of data analysis and hybrid modeling to study Callisto's interaction with Jupiter's magnetosphere during the Galileo C10 flyby on 17 September 1997. This encounter took place while Callisto was located near the center of Jupiter's current sheet. Therefore, induction in Callisto's subsurface ocean and magnetospheric field line draping around the moon's ionosphere both made nonnegligible contributions to the observed magnetic perturbations. The induction signal during C10 was obscured by plasma currents to a significant degree, in contrast to previously studied Callisto flybys. Our analysis reveals that at large distances to Callisto, its magnetic environment was dominated by field line draping, leading to the formation of Alfvén wings. Closer to the surface and in Callisto's wake, Galileo encountered a quasi-dipolar "core region" that was partially shielded from the plasma interaction and was dominated by the induced field. When exiting this core region, the spacecraft crossed a rotational discontinuity where the magnetic field vector rotated by approximately 50°. The hybrid model is able to quantitatively explain numerous key features of the observed magnetic signatures, especially the transitions between draping- and dipole-dominated regimes along the C10 trajectory. The model also reproduces the electron number density enhancement by 3-4 orders of magnitude detected in Callisto's wake, requiring a substantial ionosphere to surround the moon during C10. For flybys with nonnegligible plasma currents, comprehensive knowledge of the incident flow conditions and properties of Callisto's atmosphere is required to refine existing constraints on the subsurface ocean (conductivity, thickness, and depth) based on magnetic field data. These findings are highly relevant for the upcoming JUpiter ICy moon Explorer (JUICE) mission, which will include multiple Callisto flybys.

  6. Pushing back the frontier - A mission to the Pluto-Charon system

    Energy Technology Data Exchange (ETDEWEB)

    Farquhar, R.; Stern, S.A. (NASA, Washington, DC (USA) Colorado Univ., Boulder (USA))

    1990-08-01

    A flyby mission to Pluto is proposed. The size, orbit, atmosphere, and surface of Pluto, and the Pluto-Charon system are described. The benefits of a planetary flyby compared to ground observations are discussed in terms of imaging capabilities. Planned payloads include a plasma science package, a UV spectrometer, and a thermal mapper. The advantages of a dual launch to Mars and the need for a Jupiter-Pluto transfer are considered. A diagram of a spacecraft for a flyby study of Pluto is provided.

  7. UV emissions of Jupiter: exploration of the high-latitude regions through the UV spectrograph on NASA's Juno mission

    Science.gov (United States)

    Hue, Vincent; Gladstone, Randy; Versteeg, Maarten; Greathouse, Thomas K.; Davis, Michael; Gerard, Jean-Claude; Grodent, Denis; Bonfond, Bertrand

    2016-10-01

    The Juno mission offers the opportunity to study Jupiter, from its inner structure to its magnetospheric environment. Juno was launched on August 2011 and its Jupiter orbit insertion (JOI) planned for July 4th 2016, will place Juno in a 53.5 days capture orbit. A period reduction maneuver will be performed two orbits later to place Juno into 14-days elliptical orbits for the duration of the nominal mission, which includes 36 orbits. Juno-UVS is a UV spectrograph with a bandpass of 70 ≤ λ ≤ 205 nm, designed to characterize Jupiter UV emissions. One of the main additions of UVS compared to its predecessors is a 2.54 mm tantalum shielding, to protect it from the harsh radiation environment at Jupiter, and a scan mirror, to allow for targeting specific auroral regions during perijove passes. The scan mirror is located at the front end of the instrument and will be used to look at +/- 30° perpendicular to the Juno spin plane. The entrance slit of UVS has a dog-bone shape composed by three sections with field of views of 0.2°x2.5°, 0.025°x2.0° and 0.2°x2.5°, as projected onto the sky. It will provide new constraints on Jupiter's auroral nightside morphology and spectral features as well as the vertical structure of these emissions. It will bring remote-sensing constraints for the onboard waves and particle instruments (JADE, JEDI, Waves and MAG). The ability to change the pointing will allow relating the observed UV brightness of the regions magnetically connected to where Juno flies with the particles and waves measurements. We will discuss the planned observations and scientific targets for the nominal mission orbital sequence, which will consist of three UV datasets per orbit. We will present the results from the first orbit. As Juno orbit evolves during the mission, we will also present how these objectives evolve over time.

  8. Voyage to Jupiter.

    Science.gov (United States)

    Morrison, David; Samz, Jane

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

  9. MESSENGER'S First and Second Flybys of Mercury

    Science.gov (United States)

    Slavin, James A.

    2009-01-01

    The MESSENGER mission to Mercury offers our first opportunity to explore this planet's miniature magnetosphere since Mariner 10's brief fly-bys in 1974-5. The magnetosphere of Mercury is the smallest in the solar system with its magnetic field typically standing off the solar wind only approximately 1000 km above the surface. An overview of the MESSENGER mission and its January 14th and October 6th, 2008 close flybys of Mercury will be provided. Primary science objectives and the science instrumentation will be described. Initial results from MESSENGER will be discussed with an emphasis on the magnetic field and charged particle measurements.

  10. The Trojans' Odyssey space mission

    Science.gov (United States)

    Lamy, P.; Vernazza, P.; Groussin, O.; Poncy, J.; Martinot, V.; Hinglais, E.; Bell, J.; Cruikshank, D.; Helbert, J.; Marzari, F.; Morbidelli, A.; Rosenblatt, P.

    2011-10-01

    In our present understanding of the Solar System, small bodies (asteroids, Jupiter Trojans, comets and TNOs) are the most direct remnants of the original building blocks that formed the planets. Jupiter Trojan and Hilda asteroids are small primitive bodies located beyond the "snow line", around respectively the L4 and L5 Lagrange points of Jupiter at 5.2 AU (Trojans) and in the 2:3 mean-motion resonance with Jupiter near 3.9 AU (Hildas). They are at the crux of several outstanding and still conflicting issues regarding the formation and evolution of the Solar System. They hold the potential to unlock the answers to fundamental questions about planetary migration, the late heavy bombardment, the formation of the Jovian system, the origin and evolution of trans-neptunian objects, and the delivery of water and organics to the inner planets. The proposed Trojans' Odyssey mission is envisioned as a reconnaissance, multiple flyby mission aimed at visiting several objects, typically five Trojans and one Hilda. It will attempt exploring both large and small objects and sampling those with any known differences in photometric properties. The orbital strategy consists in a direct trajectory to one of the Trojan swarms. By carefully choosing the aphelion of the orbit (typically 5.3 AU), the trajectory will offer a long arc in the swarm thus maximizing the number of flybys. Initial gravity assists from Venus and Earth will help reducing the cruise to 7 years as well as the ?V needed for injection thus offering enough capacity to navigate among Trojans. This solution further opens the unique possibility to flyby a Hilda asteroid when leaving the Trojan swarm. During the cruise phase, a Main Belt Asteroid could be targeted if requiring a modest ?V. The specific science objectives of the mission will be best achieved with a payload that will perform high-resolution panchromatic and multispectral imaging, thermal-infrared imaging/ radiometry, near- and mid-infrared spectroscopy

  11. Ray-tracing simulations for the ultra-lightweight X-ray optics toward a future jupiter exploration mission

    Science.gov (United States)

    Mitsuishi, I.; Ezoe, Y.; Ogawa, T.; Sato, M.; Nakamura, K.; Numazawa, M.; Takeuchi, K.; Ohashi, T.; Ishikawa, K.; Mitsuda, K.

    2016-01-01

    To investigate a feasibility for in situ X-ray imaging spectrometer JUXTA (Jupiter X-ray Telescope Array) onboard a Japanese Jupiter exploration mission, we demonstrated the ideal performances, i.e., angular resolution, effective area and grasp, of our original, conically-approximated Wolter type-I MEMS-processed optics, by extending the previous ray-tracing simulator. The novel simulator enables us to study both on- and off-axis responses for our optics with two-stage optical configurations for the first time. The on-axis angular resolution is restricted to ∼ 13 μm corresponding to ∼ 10 arcsec on the detector plane without considering the diffraction effect and dominated by the diffraction effect below ∼ 1 keV (e.g., 13 arcsec at 1 keV). Si optics can achieve effective area of >700 mm2 and grasp of >1600 mm2 deg2 at our interesting energy of 600 eV. Larger effective area and grasp can be attained by employing Ni as a substrate material or Ir as a reflecting surface material. However, other factors produced in the fabrication processes such as the waviness on the mirror surface and the deformation error cause the significant performance degradation. Thus, we concluded that MEMS-processed optics can satisfy all the requirements of JUXTA only if the manufacturing accuracy can be controlled.

  12. Radiation belts of jupiter: a second look.

    Science.gov (United States)

    Fillius, R W; McIlwain, C E; Mogro-Campero, A

    1975-05-02

    The outbound leg of the Pioneer 11 Jupiter flyby explored a region farther from the equator than that traversed by Pioneer 10, and the new data require modification or augmentation of the magnetodisk model based on the Pioneer 10 flyby. The inner moons of Jupiter are sinks of energetic particles and sometimes sources. A large spike of particles was found near lo. Multiple peaks occurred in the particle fluxes near closest approach to the planet; this structure may be accounted for by a complex magnetic field configuration. The decrease in proton flux observed near minimum altitude on the Pioneer 10 flyby appears attributable to particle absorption by Amalthea.

  13. Early development of Science Opportunity Analysis tools for the Jupiter Icy Moons Explorer (JUICE) mission

    Science.gov (United States)

    Cardesin Moinelo, Alejandro; Vallat, Claire; Altobelli, Nicolas; Frew, David; Llorente, Rosario; Costa, Marc; Almeida, Miguel; Witasse, Olivier

    2016-10-01

    JUICE is the first large mission in the framework of ESA's Cosmic Vision 2015-2025 program. JUICE will survey the Jovian system with a special focus on three of the Galilean Moons: Europa, Ganymede and Callisto.The mission has recently been adopted and big efforts are being made by the Science Operations Center (SOC) at the European Space and Astronomy Centre (ESAC) in Madrid for the development of tools to provide the necessary support to the Science Working Team (SWT) for science opportunity analysis and early assessment of science operation scenarios. This contribution will outline some of the tools being developed within ESA and in collaboration with the Navigation and Ancillary Information Facility (NAIF) at JPL.The Mission Analysis and Payload Planning Support (MAPPS) is developed by ESA and has been used by most of ESA's planetary missions to generate and validate science observation timelines for the simulation of payload and spacecraft operations. MAPPS has the capability to compute and display all the necessary geometrical information such as the distances, illumination angles and projected field-of-view of an imaging instrument on the surface of the given body and a preliminary setup is already in place for the early assessment of JUICE science operations.NAIF provides valuable SPICE support to the JUICE mission and several tools are being developed to compute and visualize science opportunities. In particular the WebGeoCalc and Cosmographia systems are provided by NAIF to compute time windows and create animations of the observation geometry available via traditional SPICE data files, such as planet orbits, spacecraft trajectory, spacecraft orientation, instrument field-of-view "cones" and instrument footprints. Other software tools are being developed by ESA and other collaborating partners to support the science opportunity analysis for all missions, like the SOLab (Science Operations Laboratory) or new interfaces for observation definitions and

  14. I0-Jupiter system A unique case of Moon-Planet interaction

    CERN Document Server

    Bhardwaj, A I

    2002-01-01

    Io and Jupiter constitute a moon-planet system that is unique in our solar system. Io is the most volcanically active planetary body, while Jupiter is the first among the planets in terms of size, mass, magnetic field strength, spin rate, and volume of the magnetosphere. That Io is electrodynamically linked to Jupiter is known for nearly four decades from the radio emissions. Io influences Jupiter by supplying heavy ions to its magnetosphere, which dominates its energetic and dynamics. Jupiter influences Io by tidally heating its interior, which in turn drives the volcanic activity on Io. The role of Io and Jupiter in their mutual interaction and the nature of their coupling were first elaborated in greater detail by the two Voyagers flybys in 1979. Subsequent exploration of this system by ground-based and Earth-satellite-borne observatories and by the Galileo orbiter mission has improved our understanding of the highly complex electrodynamical interaction between Io and Jupiter many fold. A distinct feature ...

  15. Earth flyby anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Nieto, Michael Martin [Los Alamos National Laboratory; Anderson, John D [PROPULSION LAB.

    2009-01-01

    In the planet-centric system, a spacecraft should have the same initial and final energies, even though its energy and angular momentum will change in the barycenter of the solar system. However, without explanation, a number of earth flybys have yielded small energy changes.

  16. Genetic Algorithm Based Robust and Optimal Path Planning for Sample-Return Mission from an Asteroid on an Earth Fly-By Trajectory

    CERN Document Server

    Fritz, Sean

    2015-01-01

    In this study, an interplanetary space flight mission design is established to obtain the minimum \\(\\Delta V\\) required for a rendezvous and sample return mission from an asteroid. Given the initial (observed) conditions of an asteroid, a (robust) genetic algorithm is implemented to determine the optimal choice of \\(\\Delta V\\) required for the rendezvous. Robustness of the optimum solution is demonstrated through incorporated bounded-uncertainties in the outbound \\(\\Delta V\\) maneuver via genetic fitness function. The improved algorithm results in a solution with improved robustness and reduced sensitivity to propulsive errors in the outbound maneuver. This is achieved over a solution optimized solely on \\(\\Delta V\\), while keeping the increase in \\(\\Delta V\\) to a minimum, as desired. Outcomes of the analysis provide significant results in terms of improved robustness in asteroid rendezvous missions.

  17. EUROPA Multiple-Flyby Trajectory Design

    Science.gov (United States)

    Buffington, Brent; Campagnola, Stefano; Petropoulos, Anastassios

    2012-01-01

    As reinforced by the 2011 NRC Decadal Survey, Europa remains one of the most scientifically intriguing targets in planetary science due to its potential suitability for life. However, based on JEO cost estimates and current budgetary constraints, the Decadal Survey recommended-and later directed by NASA Headquarters-a more affordable pathway to Europa exploration be derived. In response, a flyby-only proof-of-concept trajectory has been developed to investigate Europa. The trajectory, enabled by employing a novel combination of new mission design techniques, successfully fulfills a set of Science Definition Team derived scientific objectives carried out by a notional payload including ice penetrating radar, topographic imaging, and short wavelength infrared observations, and ion neutral mass spectrometry in-situ measurements. The current baseline trajectory, referred to as 11-F5, consists of 34 Europa and 9 Ganymede flybys executed over the course of 2.4 years, reached a maximum inclination of 15 degrees, has a deterministic delta v of 157 m/s (post-PJR), and has a total ionizing dose of 2.06 Mrad (Si behind 100 mil Al, spherical shell). The 11-F5 trajectory and more generally speaking, flyby-only trajectories-exhibit a number of potential advantages over an Europa orbiter mission.

  18. The determination of Dione's gravity field after four Cassini flybys

    Science.gov (United States)

    Zannoni, Marco; Tortora, Paolo; Iess, Luciano; Jacobson, Robert A.; Armstrong, John W.; Asmar, Sami W.

    2015-04-01

    We present the expected accuracy in the determination of Dione's gravity field obtained through numerical simulations of all radio science flybys currently planned in the entire Cassini mission. During its tour of the Saturn system, Cassini already performed two flybys of Dione dedicated to the determination of its mass and gravity field, in October 2005 and December 2011, respectively. Two additional radio science flybys are planned in June 2015 and August 2015. The analysis of the Doppler data acquired during the closest approach of the second flyby allowed the first estimation of Dione's J2 and C22 but, given the limited amount of data, their estimation has a large correlation and cannot be considered fully reliable. Here we infer the expected final accuracy in the determination of Dione's J2 and C22 by combining the available results from the already performed experiments with numerical simulations of future flybys. The main observables considered in the analysis are two-way and three-way Doppler data obtained from the frequency shift of a highly stable microwave carrier between the spacecraft and the stations of NASA's Deep Space Network. White Gaussian noise was added to the simulated data, with a constant standard deviation for each tracking pass, obtained from an accurate noise budget of the Cassini mission. For the two flybys to be carried out in 2015, we consider a continuous coverage during +/-18 hours around the closest approach, plus one tracking pass 36 hours before and after it. The data analysis is carried out using a global, multi-arc fit, and comparing the independent solutions obtained from each flyby and different multi-arc solutions. The analysis of all four flybys is expected to provide the best, unconstrained, reliable estimation of the full quadrupole gravity field of Dione.

  19. The Convected Kappa Distribution Function at Jupiter: Details from the Voyager and Galileo Missions and a Comparison to Cassini Saturn Measurements

    Science.gov (United States)

    Kane, M.; Mitchell, D. G.; Mauk, B.; Carbary, J. F.; Hill, M. E.; Dialynas, K.; Krimigis, S. M.

    2016-12-01

    The Voyager and Galileo Missions allowed detailed measurements of 20 keV-2 MeV hot ion distributions in Jupiter's magnetosphere and beyond using the LECP detector on Voyager and EPD on Galileo. The normalized convected kappa distribution function, with isotropy assumed in the plasma convection frame, has well fit hot ion observed fluxes and thus has produced meaningful and ordered physical plasma parameters including the vector bulk velocity, the characteristic energy (temperature) of the distribution, and the high energy spectral index. The kappa model produces temperatures that indicate expansion and adiabatic cooling of hot ions in the nightside, but not in the dayside. Further, there are significant variations in the plasma parameters with time and local time. There is also a boundary layer present near but within the dawn magnetopause where distribution functions were generated from data analysis of the very distant Voyager 2 crossing of this region. Here the flow is apparently entrained into the magnetosheath flow, but temperatures are hot and consistent with rapid transport of plasma from regions of the magnetosphere closer to Jupiter. These observations have led to the proposal of an empirical model of the general convection pattern at Jupiter. Remarkably, application of the convected kappa distribution model to Saturn using Cassini INCA and CHEMS measurements produces a convection pattern and kappa distribution temperature profiles that are remarkably similar when scaled by the sub-solar magnetopause distance and radial size of the planets.

  20. Understanding Europa's Ice Shell and Subsurface Water Through Terestrial Analogs for Flyby Radar Sounding

    Science.gov (United States)

    Blankenship, D. D.; Grima, C.; Young, D. A.; Schroeder, D. M.; Soderlund, K. M.; Gim, Y.; Plaut, J. J.; Patterson, G.; Moussessian, A.

    2015-12-01

    The recently approved NASA mission to Europa proposes to study this ice-covered moon of Jupiter though a series of fly-by observations of its surface and subsurface from a spacecraft in Jovian orbit. The science goal of this mission is to "explore Europa to investigate its habitability". One of the primary instruments in the selected scientific payload is a multi-frequency, multi-channel ice penetrating radar system. The "Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON)" will play a critical role in achieving the mission's habitability driven science objectives, which include characterizing the distribution of any shallow subsurface water, searching for an ice-ocean interface and evaluating a spectrum of ice-ocean-atmosphere exchange hypotheses. The development of successful measurement and data interpretation techniques for exploring Europa will need to leverage knowledge of analogous terrestrial environments and processes. Towards this end, we will discuss a range of terrestrial radioglaciological analogs for hypothesized physical, chemical, and biological processes on Europa and present airborne data collected with the University of Texas dual-frequency radar system over a variety of terrestrial targets. These targets include water filled fractures, brine rich ice, water lenses, accreted marine ice, and ice surfaces with roughness ranging from firn to crevasse fields and will provide context for understanding and optimizing the observable signature of these processes in future radar data collected at Europa.

  1. Trade space evaluation of multi-mission architectures for the exploration of Europa

    Science.gov (United States)

    Alibay, F.; Strange, N. J.

    Recent cuts to NASA's planetary exploration budget have precipitated a debate in the community on whether large flagship missions to planetary bodies in the outer solar system or sequences of smaller missions as part of a long-term exploration program would be more beneficial. The work presented explores the trade between these two approaches as applied to the exploration of Europa and concentrates on identifying combinations of flyby, orbiter and/or lander missions that achieve high value at a lower cost than the Jupiter Europa Orbiter (JEO) flagship mission concept. The effects of the value attributed to the four main science objectives for Europa, which can be broadly classified as investigating the ocean, ice-shell, composition and geology, are demonstrated. The current approach proposed to complete the ocean exploration objective is shown to have conflicting requirements with the other three objectives. For missions that fully address all the science objectives, such as JEO, the ocean goal is therefore found to be the main cost driver. Instrument combinations for low-cost flyby missions are also presented, and simple lander designs able to achieve a wide range of objectives at a low additional cost are identified. Finally, the current designs for the Europa Habitability Mission (EHM) are compared to others in the trade space, based on the prioritization given to the science goals for the exploration of Europa. The current EHM flyby mission (Clipper) is found to be highly promising in terms of providing very high potential science value at a low cost.

  2. Cassini: Mission to Saturn and Titan

    Science.gov (United States)

    Kerridge, Stuart J.; Flury, Walter; Horn, Linda J.; Lebreton, Jean-Pierre; Stetson, Douglas S.; Stoller, Richard L.; Tan, Grace H.

    1992-01-01

    The Cassini Mission to Saturn and Titan represents an important step into the exploration of the outerplanets. It will expand on the flyby encounters of Pioneer and Voyager and parallel the detailed exploration of the Jupiter system to be accomplished by the Galileo Mission. By continuing the study of the two giant planets and enabling detailed comparisons of their structure and behavior, Cassini will provide a tremendous insight into the formation and evolution of the solar system. In addition, by virtue of its focus on the Saturnian satellite Titan, Cassini will return detailed data on an environment whose atmospheric chemistry may resemble that of the primitive Earth. The scientific objectives can be divided into five categories: Titan, Saturn, rings, icy satellites, and magnetospheres. The key area of interest to exobiologists is Titan; the other four scientific categories will be discussed briefly to provide a comprehensive overview of the Cassini Mission.

  3. Testing the Flyby Anomaly with the GNSS Constellation

    CERN Document Server

    Bertolami, O; Gil, P J S; Páramos, J

    2012-01-01

    We propose the concept of a space mission to probe the so called flyby anomaly, an unexpected velocity change experienced by some deep-space probes using earth gravity assists. The key feature of this proposal is the use of GNSS systems to obtain an increased accuracy in the tracking of the approaching spacecraft, mainly near the perigee. Two low-cost options are also discussed to further test this anomaly: an add-on to an existing spacecraft and a dedicated mission.

  4. Space Launch System Mission Flexibility Assessment

    Science.gov (United States)

    Monk, Timothy; Holladay, Jon; Sanders, Terry; Hampton, Bryan

    2012-01-01

    The Space Launch System (SLS) is envisioned as a heavy lift vehicle that will provide the foundation for future beyond low Earth orbit (LEO) missions. While multiple assessments have been performed to determine the optimal configuration for the SLS, this effort was undertaken to evaluate the flexibility of various concepts for the range of missions that may be required of this system. These mission scenarios include single launch crew and/or cargo delivery to LEO, single launch cargo delivery missions to LEO in support of multi-launch mission campaigns, and single launch beyond LEO missions. Specifically, we assessed options for the single launch beyond LEO mission scenario using a variety of in-space stages and vehicle staging criteria. This was performed to determine the most flexible (and perhaps optimal) method of designing this particular type of mission. A specific mission opportunity to the Jovian system was further assessed to determine potential solutions that may meet currently envisioned mission objectives. This application sought to significantly reduce mission cost by allowing for a direct, faster transfer from Earth to Jupiter and to determine the order-of-magnitude mass margin that would be made available from utilization of the SLS. In general, smaller, existing stages provided comparable performance to larger, new stage developments when the mission scenario allowed for optimal LEO dropoff orbits (e.g. highly elliptical staging orbits). Initial results using this method with early SLS configurations and existing Upper Stages showed the potential of capturing Lunar flyby missions as well as providing significant mass delivery to a Jupiter transfer orbit.

  5. Jupiter’s Phase Variations from Cassini: A Testbed for Future Direct-imaging Missions

    Science.gov (United States)

    Mayorga, L. C.; Jackiewicz, J.; Rages, K.; West, R. A.; Knowles, B.; Lewis, N.; Marley, M. S.

    2016-12-01

    We present empirical phase curves of Jupiter from ∼0° to 140° as measured in multiple optical bandpasses by Cassini/Imaging Science Subsystem (ISS) during the Millennium flyby of Jupiter in late 2000 to early 2001. Phase curves are of interest for studying the energy balance of Jupiter and understanding the scattering behavior of the planet as an exoplanet analog. We find that Jupiter is significantly darker at partial phases than an idealized Lambertian planet by roughly 25% and is not well fit by Jupiter-like exoplanet atmospheric models across all wavelengths. We provide analytic fits to Jupiter’s phase function in several Cassini/ISS imaging filter bandpasses. In addition, these observations show that Jupiter’s color is more variable with phase angle than predicted by models. Therefore, the color of even a near Jupiter-twin planet observed at a partial phase cannot be assumed to be comparable to that of Jupiter at full phase. We discuss how the Wide-Field Infrared Survey Telescope and other future direct-imaging missions can enhance the study of cool giants.

  6. Planetary cubesats - mission architectures

    Science.gov (United States)

    Bousquet, Pierre W.; Ulamec, Stephan; Jaumann, Ralf; Vane, Gregg; Baker, John; Clark, Pamela; Komarek, Tomas; Lebreton, Jean-Pierre; Yano, Hajime

    2016-07-01

    Miniaturisation of technologies over the last decade has made cubesats a valid solution for deep space missions. For example, a spectacular set 13 cubesats will be delivered in 2018 to a high lunar orbit within the frame of SLS' first flight, referred to as Exploration Mission-1 (EM-1). Each of them will perform autonomously valuable scientific or technological investigations. Other situations are encountered, such as the auxiliary landers / rovers and autonomous camera that will be carried in 2018 to asteroid 1993 JU3 by JAXA's Hayabusas 2 probe, and will provide complementary scientific return to their mothership. In this case, cubesats depend on a larger spacecraft for deployment and other resources, such as telecommunication relay or propulsion. For both situations, we will describe in this paper how cubesats can be used as remote observatories (such as NEO detection missions), as technology demonstrators, and how they can perform or contribute to all steps in the Deep Space exploration sequence: Measurements during Deep Space cruise, Body Fly-bies, Body Orbiters, Atmospheric probes (Jupiter probe, Venus atmospheric probes, ..), Static Landers, Mobile landers (such as balloons, wheeled rovers, small body rovers, drones, penetrators, floating devices, …), Sample Return. We will elaborate on mission architectures for the most promising concepts where cubesat size devices offer an advantage in terms of affordability, feasibility, and increase of scientific return.

  7. The Venus flybys opportunity with BEPICOLOMBO

    Science.gov (United States)

    Mangano, Valeria; de la Fuente, Sara; Montagnon, Elsa; Benkhoff, Johannes; Zender, Joe; Orsini, Stefano

    2017-04-01

    BepiColombo is a dual spacecraft mission to Mercury to be launched in October 2018 and carried out jointly between the European Space Agency (ESA) and the Japanese Aerospace Exploration Agency (JAXA). The Mercury Planetary Orbiter (MPO) payload comprises eleven experiments and instrument suites. It will focus on a global characterization of Mercury through the investigation of its interior, surface, exosphere and magnetosphere. In addition, it will test Einstein's theory of general relativity. The second spacecraft, the Mercury Magnetosphere Orbiter (MMO), will carry five experiments or instrument suites to study the environment around the planet including the planet's exosphere and magnetosphere, and their interaction processes with the solar wind. The composite spacecraft made of MPO, MMO, a transfer module (MTM) and a sunshield (MOSIF) will be launched on an escape trajectory that will bring it into heliocentric orbit on its way to Mercury. During the cruise of 7.2 years toward the inner part of the Solar System, BepiColombo will make 1 flyby to the Earth, 2 to Venus, and 6 to Mercury. Only part of its payload will be obstructed by the sunshield and the cruise spacecraft configuration, so that the two flybys to Venus will allow operations of many instruments, like: spectrometers at many wavelengths, accelerometer, radiometer, ion and electron detectors. A scientific working group has recently formed from the BepiColombo community to identify potentially interesting scientific cases and to analyse operation timelines. Preliminary outputs will be presented and discussed.

  8. Deep atmospheric probe missions to Uranus and Neptune

    Science.gov (United States)

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

    1990-01-01

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

  9. Development of radiative transfer code for JUICE/SWI mission toward the atmosphere of icy moons of Jupiter

    Science.gov (United States)

    Yamada, Takayoshi; Kasai, Yasuko; Yoshida, Naohiro

    2016-07-01

    The Submillimeter Wave Instrument (SWI) is one of the scientific instruments on the JUpiter Icy moon Explorer (JUICE). We plan to observe atmospheric compositions including water vapor and its isotopomers in Galilean moons (Io, Europa, Ganymede, and Callisto). The frequency windows of SWI are 530 to 625 GHz and 1080 to 1275 GHz with 100 kHz spectral resolution. We are developing a radiative transfer code in Japan with line-by-line method for Ganymede atmosphere in THz region (0 - 3 THz). Molecular line parameters (line intensity and partition function) were taken from JPL (Jet Propulsion Laboratory) catalogue. The pencil beam was assumed to calculate a spectrum of H _{2}O and CO in rotational transitions at the THz region. We performed comparisons between our model and ARTS (Atmospheric Radiative Transfer Simulator). The difference were less than 10% and 5% for H _{2}O and CO, respectively, under the condition of the local thermodynamic equilibrium (LTE). Comparison with several models with non-LTE assumption will be presented.

  10. The Jupiter icy moons explorer (JUICE): Complementarity of the payload in addressing the mission science objectives (abstract)

    NARCIS (Netherlands)

    Grasset, O.; Altobelli, N.; Barabash, S.; Bruzzone, L.; Dougherty, M.; Erd, C.; Fletcher, L.; Gare, P.; Gladstone, R.; Gurvits, L.; Hartogh, P.; Hussmann, H.; Jaumann, R.; Iess, L.; Langevin, Y.; Palumbo, P.; Piccioni, G...; Titov, D.; Wahlund, J.E.

    2014-01-01

    This presentation will give a status of the JUICE mission in the end of the definition phase, its science scenario, and the observation strategies that are foreseen with a strong emphasis on the complemen-tarity of the suite of instruments. To summarize, the instrument suite on-board JUICE will allo

  11. Optimal Trajectory Determination and Mission Design for Asteroid/Deep-Space Exploration via Multibody Gravity Assist Maneuvers

    Directory of Open Access Journals (Sweden)

    Sean Fritz

    2017-01-01

    Full Text Available This paper discusses the creation of a genetic algorithm to locate and optimize interplanetary trajectories using gravity assist maneuvers to improve fuel efficiency of the mission. The algorithm is implemented on two cases: (i a Centaur-class target close to the ecliptic plane and (ii a Centaur-class target with a high inclination to the ecliptic plane. Cases for multiple numbers of flybys (up to three are discussed and compared. It is shown that, for the targets considered here, a single flyby of Jupiter is the most efficient trajectory to either target with the conditions and limitations discussed in this paper. In this paper, we also iterate on possible reasons for certain results seen in the analysis and show how these previously observed behaviors could be present in any trajectory found. The parameters and methods used in the algorithm are explained and justified over multiple real-life interplanetary missions to provide deeper insights into the development choices.

  12. The Europa Clipper Mission Concept

    Science.gov (United States)

    Pappalardo, Robert; Goldstein, Barry; Magner, Thomas; Prockter, Louise; Senske, David; Paczkowski, Brian; Cooke, Brian; Vance, Steve; Wes Patterson, G.; Craft, Kate

    2014-05-01

    A NASA-appointed Science Definition Team (SDT), working closely with a technical team from the Jet Propulsion Laboratory (JPL) and the Applied Physics Laboratory (APL), recently considered options for a future strategic mission to Europa, with the stated science goal: Explore Europa to investigate its habitability. The group considered several mission options, which were fully technically developed, then costed and reviewed by technical review boards and planetary science community groups. There was strong convergence on a favored architecture consisting of a spacecraft in Jupiter orbit making many close flybys of Europa, concentrating on remote sensing to explore the moon. Innovative mission design would use gravitational perturbations of the spacecraft trajectory to permit flybys at a wide variety of latitudes and longitudes, enabling globally distributed regional coverage of the moon's surface, with nominally 45 close flybys at altitudes from 25 to 100 km. We will present the science and reconnaissance goals and objectives, a mission design overview, and the notional spacecraft for this concept, which has become known as the Europa Clipper. The Europa Clipper concept provides a cost-efficient means to explore Europa and investigate its habitability, through understanding the satellite's ice and ocean, composition, and geology. The set of investigations derived from the Europa Clipper science objectives traces to a notional payload for science, consisting of: Ice Penetrating Radar (for sounding of ice-water interfaces within and beneath the ice shell), Topographical Imager (for stereo imaging of the surface), ShortWave Infrared Spectrometer (for surface composition), Neutral Mass Spectrometer (for atmospheric composition), Magnetometer and Langmuir Probes (for inferring the satellite's induction field to characterize an ocean), and Gravity Science (to confirm an ocean).The mission would also include the capability to perform reconnaissance for a future lander

  13. Flyby Anomaly via Least Action

    Science.gov (United States)

    Annila, A.

    2017-04-01

    The observed but unexpected changes in velocity during spacecraft flybys of Earth are examined using the principle of least action in its original dissipative form. In general, the spacecraft's momentum will change when it travels through an energy density gradient of space that is enfolding a gravitating, orbiting and rotating body. When space is understood as a physical substance that embodies quanta of actions, rather than being modeled by a mere metric, it becomes apparent that the changes in momentum couple with flux of quanta from the local system of bodies to the universal surroundings or vice versa. In this way the original least-action principle accounts also for the 'anomalous' change in velocity by an equation of motion which complies with the empirical relation that has been deduced from Earth-flybys.

  14. Understanding Jupiter's Interior

    CERN Document Server

    Militzer, Burkhard; Wahl, Sean M; Hubbard, William

    2016-01-01

    This article provides an overview of how models of giant planet interiors are constructed. We review measurements from past space missions that provide constraints for the interior structure of Jupiter. We discuss typical three-layer interior models that consist of a dense central core and an inner metallic and an outer molecular hydrogen-helium layer. These models rely heavily on experiments, analytical theory, and first-principle computer simulations of hydrogen and helium to understand their behavior up to the extreme pressures ~10 Mbar and temperatures ~10,000 K. We review the various equations of state used in Jupiter models and compare them with shock wave experiments. We discuss the possibility of helium rain, core erosion and double diffusive convection may have important consequences for the structure and evolution of giant planets. In July 2016 the Juno spacecraft entered orbit around Jupiter, promising high-precision measurements of the gravitational field that will allow us to test our understandi...

  15. The Cassini-Huygens mission

    CERN Document Server

    The joint NASA-ESA Cassini-Huygens mission promises to return four (and possibly more) years of unparalleled scientific data from the solar system’s most exotic planet, the ringed, gas giant, Saturn. Larger than Galileo with a much greater communication bandwidth, Cassini can accomplish in a single flyby what Galileo returned in a series of passes. Cassini explores the Saturn environment in three dimensions, using gravity assists to climb out of the equatorial plane to look down on the rings from above, to image the aurora and to study polar magnetospheric processes such as field-aligned currents. Since the radiation belt particle fluxes are much more benign than those at Jupiter, Cassini can more safely explore the inner regions of the magnetosphere. The spacecraft approaches the planet closer than Galileo could, and explores the inner moons and the rings much more thoroughly than was possible at Jupiter. This book is the second volume, in a three volume set, that describes the Cassini/Huygens mission. Thi...

  16. Transiting exoplanets from the CoRoT space mission: VII. The "hot-Jupiter"-type planet CoRoT-5b

    CERN Document Server

    Rauer, H; Csizmadia, Sz; Deleuil, M; Alonso, R; Aigrain, S; Almenara, J M; Auvergne, M; Baglin, A; Barge, P; Borde, P; Bouchy, F; Bruntt, H; Cabrera, J; Carone, L; Carpano, S; De la Reza, R; Deeg, H J; Dvorak, R; Erikson, A; Fridlund, M; Gandolfi, D; Gillon, M; Guillot, T; Günther, E; Hatzes, A; Hébrard, G; Kabath, P; Jorda, L; Lammer, H; Léger, A; Llebaria, A; Magain, P; Mazeh, T; Moutou, C; Ollivier, M; Paetzold, M; Pont, F; Rabus, M; Renner, S; Rouan, D; Shporer, A; Samuel, B; Schneider, J; Triaud, A H M J; Wuchterl, G

    2009-01-01

    Aims. The CoRoT space mission continues to photometrically monitor about 12 000 stars in its field-of-view for a series of target fields to search for transiting extrasolar planets ever since 2007. Deep transit signals can be detected quickly in the "alarm-mode" in parallel to the ongoing target field monitoring. CoRoT's first planets have been detected in this mode. Methods. The CoRoT raw lightcurves are filtered for orbital residuals, outliers, and low-frequency stellar signals. The phase folded lightcurve is used to fit the transit signal and derive the main planetary parameters. Radial velocity follow-up observations were initiated to secure the detection and to derive the planet mass. Results. We report the detection of CoRoT-5b, detected during observations of the LRa01 field, the first long-duration field in the galactic anticenter direction. CoRoT-5b is a "hot Jupiter-type" planet with a radius of 1.388(+0.046, -0.047) R_Jup, a mass of 0.467(+0.047, -0.024) M_Jup, and therefore, a mean density of 0.21...

  17. Model Predictions and Ground-based Observations for Jupiter's Magnetospheric Environment: Application to the JUICE and Juno Missions

    Science.gov (United States)

    Achilleos, N. A.; Guio, P.; Arridge, C. S.; Ray, L. C.; Yates, J. N.; Fossey, S.; Savini, G.; Pearson, M.; Fernando, N.; Gerasimov, R.; Murat, T.

    2016-12-01

    The advent of new missions to the Jovian system such as Juno (recentlyarrived) and JUICE (scheduled for 2022 launch) makes timely the provision of model-based predictions for thephysical conditions to be encountered by these spacecraft; as well as the planning of simultaneous, ground-basedobservations of the Jovian system.Using the UCL Jovian magnetodisc model, which calculates magnetic field and plasma distributionsaccording to Caudal's (1986) force-balance formalism, we provide predictions of the following quantities alongrepresentative Juno / JUICE orbits through the middle magnetosphere: (i) Magnetic field strength and direction; (ii)Density and / or pressure of the 'cold' and 'hot' particle populations; (iii) Plasma angular velocity.The characteristic variation in these parameters is mainly influenced by the periodic approaches towards andrecessions from the magnetodisc imposed on the 'synthetic spacecraft' by the planet's rotating, tilteddipole field. We also include some corresponding predictions for ionospheric / thermospheric conditions at themagnetic footpoint of the spacecraft, using the JASMIN model (Jovian Atmospheric Simulatorwith Magnetosphere, Ionosphere and Neutrals).We also present preliminary imaging results from `IoSpot', a planned, ground-based programme of observationsbased at the University College London Observatory (UCLO) which targets ionized sulphur emissions from the Ioplasma torus. Such programmes, conducted simultaneously with the above missions, will provide valuable context forthe overall physical conditions within the Jovian magnetosphere, for which Io's volcanoes are the principal source ofplasma.

  18. Model Predictions and Ground-based Observations for Jupiter's Magnetospheric Environment: Application to the JUICE and Juno Missions

    Science.gov (United States)

    Achilleos, Nicholas; Guio, Patrick; Arridge, Christopher S.; Ray, Licia C.; Yates, Japheth N.; Fossey, Stephen J.; Savini, Giorgio; Pearson, Mick; Fernando, Nathalie; Gerasimov, Roman; Murat, Thomas

    2016-10-01

    The advent of new missions to the Jovian system such as Juno (recently arrived) and JUICE (scheduled for 2022 launch) makes timely the provision of model-based predictions for the physical conditions to be encountered by these spacecraft; as well as the planning of simultaneous, ground-based observations of the Jovian system.Using the UCL Jovian magnetodisc model, which calculates magnetic field and plasma distributionsaccording to Caudal's (1986) force-balance formalism, we provide predictions of the following quantities along representative Juno / JUICE orbits through the middle magnetosphere: (i) Magnetic field strength and direction; (ii) Density and / or pressure of the 'cold' and 'hot' particle populations; (iii) Plasma angular velocity.The characteristic variation in these parameters is mainly influenced by the periodic approaches towards and recessions from the magnetodisc imposed on the 'synthetic spacecraft' by the planet's rotating, tilteddipole field. We also include some corresponding predictions for ionospheric / thermospheric conditions at the magnetic footpoint of the spacecraft, using the JASMIN model (Jovian Atmospheric Simulatorwith Magnetosphere, Ionosphere and Neutrals).We also present preliminary imaging results from 'IoSpot', a planned, ground-based programme of observations based at the University College London Observatory (UCLO) which targets ionized sulphur emissions from the Io plasma torus. Such programmes, conducted simultaneously with the above missions, will provide valuable context for the overall physical conditions within the Jovian magnetosphere, for which Io's volcanoes are the principal source of plasma.

  19. Broad search for trajectories from Earth to Callisto-Ganymede-JOI double-satellite-aided capture at Jupiter from 2020 to 2060

    Science.gov (United States)

    Lynam, Alfred E.

    2016-01-01

    Employing multiple gravity-assist flybys of Jupiter's Galilean moons can save a substantial amount of \\varDelta V when capturing into orbit about Jupiter. Using Callisto and Ganymede, the most massive and distant of the Galilean moons, as gravity-assist bodies reduces the Jupiter orbit insertion \\varDelta V cost, while allowing the spacecraft to remain above the worst of Jupiter's radiation belts. A phase-angle approach is used to find initial guesses for a Lambert targeter to find patched-conic Callisto-Ganymede transfers. A B-plane targeter using grid search methodology is used to backward target Earth to find launch conditions. Twenty-nine distinct patched-conic trajectories were found from Earth to Callisto-Ganymede-JOI capture throughout the search space from 2020-2060. Five promising trajectories were found that launch from Earth between July 11, 2023 and July 20, 2023, and arrive at Jupiter between February and September 2026. These trajectories were numerically integrated using GMAT and, in the author's opinion, are excellent candidates for use on NASA's planned Europa Clipper mission.

  20. Jupiter Eruptions

    Science.gov (United States)

    2008-01-01

    [figure removed for brevity, see original site] Click on the image for high resolution image of Nature Cover Detailed analysis of two continent-sized storms that erupted in Jupiter's atmosphere in March 2007 shows that Jupiter's internal heat plays a significant role in generating atmospheric disturbances. Understanding these outbreaks could be the key to unlock the mysteries buried in the deep Jovian atmosphere, say astronomers. This visible-light image is from NASA's Hubble Space Telescope taken on May 11, 2007. It shows the turbulent pattern generated by the two plumes on the upper left part of Jupiter. Understanding these phenomena is important for Earth's meteorology where storms are present everywhere and jet streams dominate the atmospheric circulation. Jupiter is a natural laboratory where atmospheric scientists study the nature and interplay of the intense jets and severe atmospheric phenomena. According to the analysis, the bright plumes were storm systems triggered in Jupiter's deep water clouds that moved upward in the atmosphere vi gorously and injected a fresh mixture of ammonia ice and water about 20 miles (30 kilometers) above the visible clouds. The storms moved in the peak of a jet stream in Jupiter's atmosphere at 375 miles per hour (600 kilometers per hour). Models of the disturbance indicate that the jet stream extends deep in the buried atmosphere of Jupiter, more than 60 miles (approximately100 kilometers) below the cloud tops where most sunlight is absorbed.

  1. Axi-symmetric models of auroral current systems in Jupiter's magnetosphere with predictions for the Juno mission

    Directory of Open Access Journals (Sweden)

    S. W. H. Cowley

    2008-12-01

    Full Text Available We develop two related models of magnetosphere-ionosphere coupling in the jovian system by combining previous models defined at ionospheric heights with magnetospheric magnetic models that allow system parameters to be extended appropriately into the magnetosphere. The key feature of the combined models is thus that they allow direct connection to be made between observations in the magnetosphere, particularly of the azimuthal field produced by the magnetosphere-ionosphere coupling currents and the plasma angular velocity, and the auroral response in the ionosphere. The two models are intended to reflect typical steady-state sub-corotation conditions in the jovian magnetosphere, and transient super-corotation produced by sudden major solar wind-induced compressions, respectively. The key simplification of the models is that of axi-symmetry of the field, flow, and currents about the magnetic axis, limiting their validity to radial distances within ~30 RJ of the planet, though the magnetic axis is appropriately tilted relative to the planetary spin axis and rotates with the planet. The first exploration of the jovian polar magnetosphere is planned to be undertaken in 2016–2017 during the NASA New Frontiers Juno mission, with observations of the polar field, plasma, and UV emissions as a major goal. Evaluation of the models along Juno planning orbits thus produces predictive results that may aid in science mission planning. It is shown in particular that the low-altitude near-periapsis polar passes will generally occur underneath the corresponding auroral acceleration regions, thus allowing brief examination of the auroral primaries over intervals of ~1–3 min for the main oval and ~10 s for narrower polar arc structures, while the "lagging" field deflections produced by the auroral current systems on these passes will be ~0.1°, associated with azimuthal fields above the ionosphere of a few hundred nT.

  2. Gravity Science with The JUICE Mission

    Science.gov (United States)

    Parisi, M.; Finocchiaro, S.; Iess, L.

    2012-04-01

    JUICE (Jupiter Icy Moon Explorer) is a European mission to the Jovian system, proposed in the frame of the ESA Cosmic Vision program. The spacecraft will reach the Jovian system and fly several times by the moons Callisto and Europa before being inserted in a nearly circular, polar orbit around Ganymede. After its arrival in 2030, the mission timeline entails two Europa flybys (2030), twelve Callisto flybys (2031) and the orbital phase at Ganymede (2033) [1]. Gravity measurements will provide crucial information on the interior structure of the three satellites. If the bodies are in hydrostatic equilibrium, the radial density distribution may be constrained from their moment of inertia factor and low-degree gravity field coefficients [2]. Furthermore, the determination of the high-degree harmonics will provide the distribution of gravity anomalies. Evidence for subsurface oceans within Ganymede and Callisto, one of the main scientific goals of the mission, will be obtained by the determination of the tidal Love number k2 as part of a global solution for the static and variable gravity field. Gravity fields and tidal deformations will be determined by means of precise Doppler tracking of the spacecraft in Ka-band (32.5-34 GHz). The Radio Science Instrument (RSI) is enabled by a Ka-band transponder which, complemented by suitable ground instrumentation, will enable a radio link with a very high phase stability. The main observable quantity for gravity field determination is the range rate (to 3 micron/s at 1000 s integration time, two-way). The spacecraft range (accurate to 20 cm, two-way) will be used to improve the ephemerides of the Jupiter system. Gravity science at Ganymede will be carried out during the orbital phase. According to the mission profile (subject to change), the first 102 days will be spent at an altitude of 500 km. The orbit will be lowered to 200 km in the last 32 days of the mission. If the spacecraft will be endowed with a steerable medium gain

  3. Main methods of trajectory synthesis for scenarios of space missions with gravity assist maneuvers in the system of Jupiter and with landing on one of its satellites

    Science.gov (United States)

    Golubev, Yu. F.; Tuchin, A. G.; Grushevskii, A. V.; Koryanov, V. V.; Tuchin, D. A.; Morskoy, I. M.; Simonov, A. V.; Dobrovolskii, V. S.

    2016-12-01

    The development of a methodology for designing trajectories of spacecraft intended for the contact and remote studies of Jupiter and its natural satellites is considered. This methodology should take into account a number of specific features. Firstly, in order to maintain the propellant consumption at an acceptable level, the flight profile, ensuring the injection of the spacecraft into orbit around the Jovian moon, should include a large number of gravity assist maneuvers both in the interplanetary phase of the Earth-to-Jupiter flight and during the flight in the system of the giant planet. Secondly, the presence of Jupiter's powerful radiation belts also imposes fairly strict limitations on the trajectory parameters.

  4. Transiting exoplanets from the CoRoT space mission. XVIII. CoRoT-18b: a massive hot Jupiter on a prograde, nearly aligned orbit

    Science.gov (United States)

    Hébrard, G.; Evans, T. M.; Alonso, R.; Fridlund, M.; Ofir, A.; Aigrain, S.; Guillot, T.; Almenara, J. M.; Auvergne, M.; Baglin, A.; Barge, P.; Bonomo, A. S.; Bordé, P.; Bouchy, F.; Cabrera, J.; Carone, L.; Carpano, S.; Cavarroc, C.; Csizmadia, Sz.; Deeg, H. J.; Deleuil, M.; Díaz, R. F.; Dvorak, R.; Erikson, A.; Ferraz-Mello, S.; Gandolfi, D.; Gibson, N.; Gillon, M.; Guenther, E.; Hatzes, A.; Havel, M.; Jorda, L.; Lammer, H.; Léger, A.; Llebaria, A.; Mazeh, T.; Moutou, C.; Ollivier, M.; Parviainen, H.; Pätzold, M.; Queloz, D.; Rauer, H.; Rouan, D.; Santerne, A.; Schneider, J.; Tingley, B.; Wuchterl, G.

    2011-09-01

    We report the detection of CoRoT-18b, a massive hot Jupiter transiting in front of its host star with a period of 1.9000693 ± 0.0000028 days. This planet was discovered thanks to photometric data secured with the CoRoT satellite combined with spectroscopic and photometric ground-based follow-up observations. The planet has a mass Mp = 3.47 ± 0.38 MJup, a radius Rp = 1.31 ± 0.18 RJup, and a density ρp = 2.2 ± 0.8 g cm-3. It orbits a G9V star with a mass M⋆ = 0.95 ± 0.15 M⊙, a radius R⋆ = 1.00 ± 0.13 R⊙, and arotation period Prot = 5.4 ± 0.4 days. The age of the system remains uncertain, with stellar evolution models pointing either to a few tens Ma or several Ga, while gyrochronology and lithium abundance point towards ages of a few hundred Ma. This mismatch potentially points to a problem in our understanding of the evolution of young stars, with possibly significant implications for stellar physics and the interpretation of inferred sizes of exoplanets around young stars. We detected the Rossiter-McLaughlin anomaly in the CoRoT-18 system thanks to the spectroscopic observation of a transit. We measured the obliquity ψ = 20° ± 20° (sky-projected value λ = -10° ± 20°), indicating that the planet orbits in the same way as the star is rotating and that this prograde orbit is nearly aligned with the stellar equator. The CoRoT space mission, launched on 2006 December 27, has been developed and is operated by CNES, with the contribution of Austria, Belgium, Brazil, ESA (RSSD and Science Programme), Germany and Spain.Table 2 is available in electronic form at http://www.aanda.org

  5. Rosetta performs ESA's closest-ever Earth fly-by

    Science.gov (United States)

    2005-03-01

    The passage through the Earth-Moon system allowed ground controllers to test Rosetta's 'asteroid fly-by mode' (AFM) using the Moon as a 'fake' asteroid, rehearsing the fly-bys of asteroids Steins and Lutetia due in 2008 and 2010 respectively. The AFM test started at 23:01 GMT and ran for nine minutes during which the two onboard navigation cameras successfully tracked the Moon, allowing Rosetta's attitude to be automatically adjusted. Before and after closest approach, the navigation cameras also acquired a series of images of the Moon and Earth; these data will be downloaded early today for ground processing and are expected to be available by 8 March. In addition, other onboard instruments were switched on, including ALICE (ultraviolet imaging spectrometer), VIRTIS (visible and infrared mapping spectrometer) and MIRO (microwave instrument for the Rosetta orbiter), for calibration and general testing using the Earth and Moon as targets. The fly-by manoeuvre swung the three-tonne spacecraft around our planet and out towards Mars, where it will make a fly-by on 26 February 2007. Rosetta will return to Earth again in a series of four planet fly-bys (three times with Earth, once with Mars) before reaching Comet 67P/Churyumov-Gerasimenko in 2014, when it will enter orbit and deliver a lander, Philae, onto the surface. The fly-bys are necessary to accelerate the spacecraft so as to eventually match the velocity of the target comet. They are a fuel-saving way to boost speed using planetary gravity. Yesterday's fly-by came one year and two days after launch and highlights the valuable opportunities for instrument calibration and data gathering available during the mission's multi-year voyage. In just three months, on 4 July, Rosetta will be in a good position to observe and gather data during NASA's spectacular Deep Impact event, when the Deep Impact probe will hurl a 380 kg projectile into Comet Tempel 1, revealing data on the comet's internal structure. Certain of

  6. Principal components analysis of Jupiter VIMS spectra

    Science.gov (United States)

    Bellucci, G.; Formisano, V.; D'Aversa, E.; Brown, R.H.; Baines, K.H.; Bibring, J.-P.; Buratti, B.J.; Capaccioni, F.; Cerroni, P.; Clark, R.N.; Coradini, A.; Cruikshank, D.P.; Drossart, P.; Jaumann, R.; Langevin, Y.; Matson, D.L.; McCord, T.B.; Mennella, V.; Nelson, R.M.; Nicholson, P.D.; Sicardy, B.; Sotin, Christophe; Chamberlain, M.C.; Hansen, G.; Hibbits, K.; Showalter, M.; Filacchione, G.

    2004-01-01

    During Cassini - Jupiter flyby occurred in December 2000, Visual-Infrared mapping spectrometer (VIMS) instrument took several image cubes of Jupiter at different phase angles and distances. We have analysed the spectral images acquired by the VIMS visual channel by means of a principal component analysis technique (PCA). The original data set consists of 96 spectral images in the 0.35-1.05 ??m wavelength range. The product of the analysis are new PC bands, which contain all the spectral variance of the original data. These new components have been used to produce a map of Jupiter made of seven coherent spectral classes. The map confirms previously published work done on the Great Red Spot by using NIMS data. Some other new findings, presently under investigation, are presented. ?? 2004 Published by Elsevier Ltd on behalf of COSPAR.

  7. Featured Image: Mapping Jupiter with Hubble

    Science.gov (United States)

    Kohler, Susanna

    2016-07-01

    Zonal wind profile for Jupiter, describing the speed and direction of its winds at each latitude. [Simon et al. 2015]This global map of Jupiters surface (click for the full view!) was generated by the Hubble Outer Planet Atmospheres Legacy (OPAL) program, which aims to createnew yearly global maps for each of the outer planets. Presented in a study led by Amy Simon (NASA Goddard Space Flight Center), the map above is the first generated for Jupiter in the first year of the OPAL campaign. It provides a detailed look at Jupiters atmospheric structure including the Great Red Spot and allowed the authors to measure the speed and direction of the wind across Jupiters latitudes, constructing an updated zonal wind profile for Jupiter.In contrast to this study, the Juno mission (which will be captured into Jupiters orbit today after a 5-year journey to Jupiter!) will be focusing more on the features below Jupiters surface, studying its deep atmosphere and winds. Some of Junos primary goals are to learn about Jupiters composition, gravitational field, magnetic field, and polar magnetosphere. You can follow along with the NASATV livestream as Juno arrives at Jupiter tonight; orbit insertion coverage starts at 10:30 EDT.CitationAmy A. Simon et al 2015 ApJ 812 55. doi:10.1088/0004-637X/812/1/55

  8. rosuvastatin (JUPITER)

    DEFF Research Database (Denmark)

    Nordestgaard, Børge; Ridker, Paul M; MacFadyen, Jean G;

    2009-01-01

    were calculated across a range of end points, timeframes, and subgroups using data from Justification for the Use of statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER), a randomized evaluation of rosuvastatin 20 mg versus placebo conducted among 17 802 apparently healthy men...... infarction, stroke, revascularization, or death, the 5-year NNT within JUPITER was 20 (95% CI, 14 to 34). All subgroups had 5-year NNT values for this end point below 50; as examples, 5-year NNT values were 17 for men and 31 for women, 21 for whites and 19 for nonwhites, 18 for those with body mass index 300...

  9. Extreme Environments Technologies for Probes to Venus and Jupiter

    Science.gov (United States)

    Balint, Tibor S.; Kolawa, Elizabeth A.; Peterson, Craig E.; Cutts, James A.; Belz, Andrea P.

    2007-01-01

    This viewgraph presentation reviews the technologies that are used to mitigate extreme environments for probes at Venus and Jupiter. The contents include: 1) Extreme environments at Venus and Jupiter; 2) In-situ missions to Venus and Jupiter (past/present/future); and 3) Approaches to mitigate conditions of extreme environments for probes with systems architectures and technologies.

  10. Encouragement from Jupiter for Europe's Titan Probe

    Science.gov (United States)

    1996-04-01

    continue about whether the Probe hit by chance a patch of unusual weather, whether instruments were misreading, or whether ideas about the giant planet need a thorough shake-up. "The Jupiter experience teaches us to be more modest in our predictions about what a new world will be like," says Dr Lebreton. "It shows the limitations of theories made from telescope studies and flybys, and confirms the need for on-the-spot observations. We know far less about Titan than about Jupiter. So a real understanding of Titan must await the arrival of Cassini/ Huygens in eight years' time." Hazy orange clouds obscure Titan and leave scientists guessing about what Huygens will find. As speculation and debate continue, the biggest uncertainty concerns the nature of Titan's surface. Some experts expect to find large lakes of liquid hydrocarbons, while others suspect that the surface is dry. The hypothesis that a global ocean might cover Titan is out of fashion at present, because of radar results and reasoning about the effects of tides in a global ocean. The multinational teams of scientists who have developed the instruments on Huygens are prepared for surprises. For example, the Surface Science Package is designed for a wet or a dry landing, and will give appropriate results in either case. Further tests planned With just eighteen months to go until the launch of the joint Cassini/Huygens mission in October 1997, the spring of 1996 is a busy time for the Huygens teams. The first European flight hardware reached NASA's Jet Propulsion Laboratory (JPL) for incorporation in the Flight Model of the Cassini Orbiter. This is the Probe Support Avionics, which receives and processes the signals from the Probe at Titan. The Engineering Model of Huygens has also gone to JPL, for comprehensive electrical tests of the Cassini spacecraft. ESA is planning to carry out further tests on the Flight Model of Huygens, which is due for delivery in less than a year's time. The aim is to settle questions

  11. Joint NASA-ESA Outer Planet Mission study overview

    Science.gov (United States)

    Lebreton, J.-P.; Niebur, C.; Cutts, J.; Falkner, P.; Greeley, R.; Lunine, J.; Blanc, M.; Coustenis, A.; Pappalardo, R.; Matson, D.; Clark, K.; Reh, K.; Stankov, A.; Erd, C.; Beauchamp, P.

    2009-04-01

    In 2008, ESA and NASA performed joint studies of two highly capable scientific missions to the outer planets: the Europa Jupiter System Mission (EJSM) and the Titan Saturn System Mission (TSSM). Joint Science Definition Teams (JSDTs) were formed with U.S. and European membership to guide study activities that were conducted collaboratively by engineering teams working on both sides of the Atlantic. EJSM comprises the Jupiter Europa Orbiter (JEO) that would be provided by NASA and the Jupiter Ganymede Orbiter (JGO) that would be provided by ESA. Both spacecraft would be launched independently in 2020, and arrive 6 years later for a 3-4 year mission within the Jupiter System. Both orbiters would explore Jupiter's system on trajectories that include flybys of Io (JEO only), Europa (JEO only), Ganymede and Callisto. The operation of JEO would culminate in orbit around Europa while that of JGO would culminate in orbit around Ganymede. Synergistic and coordinated observations would be planned. The Titan Saturn System Mission (TSSM) comprises a Titan Orbiter provided by NASA that would carry two Titan in situ elements provided by ESA: the montgolfière and the lake lander. The mission would launch in 2020 and arrive 9 years later for a 4-year duration in the Saturn system. Following delivery of the ESA in situ elements to Titan, the Titan Orbiter would explore the Saturn system via a 2-year tour that includes Enceladus and Titan flybys. The montgolfière would last at least 6-12 months at Titan and the lake lander 8-10 hours. Following the Saturn system tour, the Titan Orbiter would culminate in a ~2-year orbit around Titan. Synergistic and coordinated observations would be planned between the orbiter and in situ elements. The ESA contribution to this joint endeavor will be implemented as the first Cosmic Vision Large-class (L1) mission; the NASA contribution will be implemented as the Outer Planet Flagship Mission. The contribution to each mission is being reviewed and

  12. Juno's Earth flyby: the Jovian infrared Auroral Mapper preliminary results

    Science.gov (United States)

    Adriani, A.; Moriconi, M. L.; Mura, A.; Tosi, F.; Sindoni, G.; Noschese, R.; Cicchetti, A.; Filacchione, G.

    2016-08-01

    The Jovian InfraRed Auroral Mapper, JIRAM, is an image-spectrometer onboard the NASA Juno spacecraft flying to Jupiter. The instrument has been designed to study the aurora and the atmosphere of the planet in the spectral range 2-5 μm. The very first scientific observation taken with the instrument was at the Moon just before Juno's Earth fly-by occurred on October 9, 2013. The purpose was to check the instrument regular operation modes and to optimize the instrumental performances. The testing activity will be completed with pointing and a radiometric/spectral calibrations shortly after Jupiter Orbit Insertion. Then the reconstruction of some Moon infrared images, together with co-located spectra used to retrieve the lunar surface temperature, is a fundamental step in the instrument operation tuning. The main scope of this article is to serve as a reference to future users of the JIRAM datasets after public release with the NASA Planetary Data System.

  13. Transiting exoplanets from the CoRoT space mission: XIII. CoRoT-14b: an unusually dense very hot Jupiter

    CERN Document Server

    Tingley, B; Gazzano, J -C; Alonso, R; Mazeh, T; Jorda, L; Aigrain, S; Almenara, J -M; Auvergne, M; Baglin, A; Barge, P; Bonomo, A S; Bordé, P; Bouchy, F; Bruntt, H; Cabrera, J; Carpano, S; Carone, L; Cochran, W D; Csizmadia, Sz; Deleuil, M; Deeg, H J; Dvorak, R; Erikson, A; Ferraz-Mello, S; Fridlund, M; Gandolfi, D; Gillon, M; Guenther, E W; Guillot, T; Hatzes, A; Hébrard, G; Léger, A; Llebaria, A; Lammer, H; Lovis, C; MacQueen, P J; Moutou, C; Ollivier, M; Ofir, A; Pätzold, M; Pepe, F; Queloz, D; Rauer, H; Rouan, D; Samuel, B; Schneider, J; Shporer, A; Wuchterl, G

    2011-01-01

    In this paper, the CoRoT Exoplanet Science Team announces its 14th discovery. Herein, we discuss the observations and analyses that allowed us to derive the parameters of this system: a hot Jupiter with a mass of $7.6 \\pm 0.6$ Jupiter masses orbiting a solar-type star (F9V) with a period of only 1.5 d, less than 5 stellar radii from its parent star. It is unusual for such a massive planet to have such a small orbit: only one other known exoplanet with a higher mass orbits with a shorter period.

  14. The Europa Clipper mission concept

    Science.gov (United States)

    Pappalardo, Robert; Lopes, Rosaly

    Jupiter's moon Europa may be a habitable world. Galileo spacecraft data suggest that an ocean most likely exists beneath Europa’s icy surface and that the “ingredients” necessary for life (liquid water, chemistry, and energy) could be present within this ocean today. Because of the potential for revolutionizing our understanding of life in the solar system, future exploration of Europa has been deemed an extremely high priority for planetary science. A NASA-appointed Science Definition Team (SDT), working closely with a technical team from the Jet Propulsion Laboratory (JPL) and the Applied Physics Laboratory (APL), recently considered options for a future strategic mission to Europa, with the stated science goal: Explore Europa to investigate its habitability. The group considered several mission options, which were fully technically developed, then costed and reviewed by technical review boards and planetary science community groups. There was strong convergence on a favored architecture consisting of a spacecraft in Jupiter orbit making many close flybys of Europa, concentrating on remote sensing to explore the moon. Innovative mission design would use gravitational perturbations of the spacecraft trajectory to permit flybys at a wide variety of latitudes and longitudes, enabling globally distributed regional coverage of the moon’s surface, with nominally 45 close flybys at altitudes from 25 to 100 km. We will present the science and reconnaissance goals and objectives, a mission design overview, and the notional spacecraft for this concept, which has become known as the Europa Clipper. The Europa Clipper concept provides a cost-efficient means to explore Europa and investigate its habitability, through understanding the satellite’s ice and ocean, composition, and geology. The set of investigations derived from these science objectives traces to a notional payload for science, consisting of: Ice Penetrating Radar (for sounding of ice-water interfaces

  15. Jupiter's Moons: Family Portrait

    Science.gov (United States)

    2007-01-01

    This montage shows the best views of Jupiter's four large and diverse 'Galilean' satellites as seen by the Long Range Reconnaissance Imager (LORRI) on the New Horizons spacecraft during its flyby of Jupiter in late February 2007. The four moons are, from left to right: Io, Europa, Ganymede and Callisto. The images have been scaled to represent the true relative sizes of the four moons and are arranged in their order from Jupiter. Io, 3,640 kilometers (2,260 miles) in diameter, was imaged at 03:50 Universal Time on February 28 from a range of 2.7 million kilometers (1.7 million miles). The original image scale was 13 kilometers per pixel, and the image is centered at Io coordinates 6 degrees south, 22 degrees west. Io is notable for its active volcanism, which New Horizons has studied extensively. Europa, 3,120 kilometers (1,938 miles) in diameter, was imaged at 01:28 Universal Time on February 28 from a range of 3 million kilometers (1.8 million miles). The original image scale was 15 kilometers per pixel, and the image is centered at Europa coordinates 6 degrees south, 347 degrees west. Europa's smooth, icy surface likely conceals an ocean of liquid water. New Horizons obtained data on Europa's surface composition and imaged subtle surface features, and analysis of these data may provide new information about the ocean and the icy shell that covers it. New Horizons spied Ganymede, 5,262 kilometers (3,268 miles) in diameter, at 10:01 Universal Time on February 27 from 3.5 million kilometers (2.2 million miles) away. The original scale was 17 kilometers per pixel, and the image is centered at Ganymede coordinates 6 degrees south, 38 degrees west. Ganymede, the largest moon in the solar system, has a dirty ice surface cut by fractures and peppered by impact craters. New Horizons' infrared observations may provide insight into the composition of the moon's surface and interior. Callisto, 4,820 kilometers (2,995 miles) in diameter, was imaged at 03:50 Universal Time on

  16. Overview of Juno Results at Jupiter

    Science.gov (United States)

    Bolton, Scott; Connerney, Jack; Levin, Steve

    2017-04-01

    Juno is the first mission to investigate Jupiter using a close polar orbit. The Juno science goals include the study of Jupiter interior composition and structure, deep atmosphere and its polar magnetosphere. All orbits have peri-jove at approximately 5000 km above Jupiter's visible cloud tops. The payload consists of a set of microwave antennas for deep sounding, magnetometers, gravity radio science, low and high energy charged particle detectors, plasma wave antennas, ultraviolet imaging spectrograph, infrared imager and spectrometer and a visible camera. The Juno mission design, an overview of the early science results from Juno, and a description of the collaborative Earth based campaign will be presented.

  17. Transiting exoplanets from the CoRoT space mission . XIX. CoRoT-23b: a dense hot Jupiter on an eccentric orbit

    DEFF Research Database (Denmark)

    Rouan, D.; Parviainen, H.; Moutou, C.

    2012-01-01

    We report the detection of CoRoT-23b, a hot Jupiter transiting in front of its host star with a period of 3.6314 ± 0.0001 days. This planet was discovered thanks to photometric data secured with the CoRoT satellite, combined with spectroscopic radial velocity (RV) measurements. A photometric sear...

  18. Transiting exoplanets from the CoRoT space mission . XIX. CoRoT-23b: a dense hot Jupiter on an eccentric orbit

    DEFF Research Database (Denmark)

    Rouan, D.; Parviainen, H.; Moutou, C.

    2012-01-01

    We report the detection of CoRoT-23b, a hot Jupiter transiting in front of its host star with a period of 3.6314 ± 0.0001 days. This planet was discovered thanks to photometric data secured with the CoRoT satellite, combined with spectroscopic radial velocity (RV) measurements. A photometric sear...

  19. Engineering a Solution to Jupiter Exploration

    Science.gov (United States)

    Clark, Karla; Magner, Thomas; Lisano, Michael; Pappalardo, Robert

    2010-01-01

    The Europa Jupiter System Mission (EJSM) would be an international mission with the overall theme of investigating the emergence of habitable worlds around gas giants. Its goals are to (1) explore Europa to investigate its habitability, (2) characterize Ganymede as a planetary object including its potential habitability and (3) explore the Jupiter system as an archetype for gas giants. NASA and ESA have concluded a detailed joint study of a mission to Europa, Ganymede, and the Jupiter system with conceptual orbiters developed by NASA and ESA. The baseline EJSM architecture consists of two primary elements operating simultaneously in the Jovian system: the NASA-led Jupiter Europa Orbiter (JEO), and the ESA-led Jupiter Ganymede Orbiter (JGO). JEO and JGO would execute an intricately choreographed exploration of the Jupiter System before settling into orbit around Europa and Ganymede, respectively. EJSM would directly address themes concerning the origin and evolution of satellite systems and water-rich environments in icy satellites. The potential habitability of the ocean-bearing moons Europa and Ganymede would be investigated, by characterizing the geophysical, compositional, geological, and external processes that affect these icy worlds. EJSM would also investigate Io and Callisto, Jupiter's atmosphere, and the Jovian magnetosphere. By understanding the Jupiter system and unraveling its history, the formation and evolution of gas giant planets and their satellites would be better known. Most importantly, EJSM would shed new light on the potential for the emergence of life in the celestial neighborhood and beyond. The EJSM baseline architecture would provide opportunities for coordinated synergistic observations by JEO and JGO of the Jupiter and Ganymede magnetospheres, the volcanoes and torus of Io, the atmosphere of Jupiter, and comparative planetology of icy satellites. Each spacecraft would conduct both synergistic dual-spacecraft investigations and stand

  20. Solar Probe Plus: Mission design challenges and trades

    Science.gov (United States)

    Guo, Yanping

    2010-11-01

    NASA plans to launch the first mission to the Sun, named Solar Probe Plus, as early as 2015, after a comprehensive feasibility study that significantly changed the original Solar Probe mission concept. The original Solar Probe mission concept, based on a Jupiter gravity assist trajectory, was no longer feasible under the new guidelines given to the mission. A complete redesign of the mission was required, which called for developing alternative trajectories that excluded a flyby of Jupiter. Without the very powerful gravity assist from Jupiter it was extremely difficult to get to the Sun, so designing a trajectory to reach the Sun that is technically feasible under the new mission guidelines became a key enabler to this highly challenging mission. Mission design requirements and challenges unique to this mission are reviewed and discussed, including various mission scenarios and six different trajectory designs utilizing various planetary gravity assists that were considered. The V 5GA trajectory design using five Venus gravity assists achieves a perihelion of 11.8 solar radii ( RS) in 3.3 years without any deep space maneuver (DSM). The V 7GA trajectory design reaches a perihelion of 9.5 RS using seven Venus gravity assists in 6.39 years without any DSM. With nine Venus gravity assists, the V 9GA trajectory design shows a solar orbit at inclination as high as 37.9° from the ecliptic plane can be achieved with the time of flight of 5.8 years. Using combined Earth and Venus gravity assists, as close as 9 RS from the Sun can be achieved in less than 10 years of flight time at moderate launch C3. Ultimately the V 7GA trajectory was chosen as the new baseline mission trajectory. Its design allowing for science investigation right after launch and continuing for nearly 7 years is unprecedented for interplanetary missions. The redesigned Solar Probe Plus mission is not only feasible under the new guidelines but also significantly outperforms the original mission concept

  1. Jupiter small satellite montage

    Science.gov (United States)

    2000-01-01

    A montage of images of the small inner moons of Jupiter from the camera onboard NASA's Galileo spacecraft shows the best views obtained of these moons during Galileo's 11th orbit around the giant planet in November 1997. At that point, Galileo was completing its first two years in Jupiter orbit--known as the Galileo 'prime mission'--and was about to embark on a successful two-year extension, called the Galileo Europa Mission. The top two images show the moon Thebe. Thebe rotates by approximately 50 degrees between the time these two images were taken, so that the same prominent impact crater is seen in both views; this crater, which has been given the provisional name Zethus, is near the point on Thebe that faces permanently away from Jupiter. The next two images show the moon Amalthea; they were taken with the Sun directly behind the observer, an alignment that emphasizes patterns of intrinsically bright or dark surface material. The third image from the top is a view of Amalthea's leading side, the side of the moon that 'leads' as Amalthea moves in its orbit around Jupiter. This image looks 'noisy' because it was obtained serendipitously during an observation of the Jovian satellite Io (Amalthea and Io shared the same camera frame but the image was exposed for bright Io rather than for the much darker Amalthea). The fourth image from the top emphasizes prominent 'spots' of relatively bright material that are located near the point on Amalthea that faces permanently away from Jupiter. The bottom image is a view of the tiny moon Metis. In all the images, north is approximately up, and the moons are shown in their correct relative sizes. The images are, from top to bottom: Thebe taken on November 7, 1997 at a range of 504,000 kilometers (about 313,000 miles); Thebe on November 7, 1997 at a range of 548,000 kilometers (about 340,000 miles); Amalthea on November 6, 1997 at a range of about 650,000 kilometers (about 404,000 miles); Amalthea on November 7, 1997 at a

  2. Optical Navigation Preparations for New Horizons Pluto Flyby

    Science.gov (United States)

    Owen, William M., Jr.; Dumont, Philip J.; Jackman, Coralie D.

    2012-01-01

    The New Horizons spacecraft will encounter Pluto and its satellites in July 2015. As was the case for the Voyager encounters with Jupiter, Saturn, Uranus and Neptune, mission success will depend heavily on accurate spacecraft navigation, and accurate navigation will be impossible without the use of pictures of the Pluto system taken by the onboard cameras. We describe the preparations made by the New Horizons optical navigators: picture planning, image processing algorithms, software development and testing, and results from in-flight imaging.

  3. Cassini Solstice Mission Maneuver Experience: Year One

    Science.gov (United States)

    Wagner, Sean V.; Arrieta, Juan; Ballard, Christopher G.; Hahn, Yungsun; Stumpf, Paul W.; Valerino, Powtawche N.

    2011-01-01

    The Cassini-Huygens spacecraft began its four-year Prime Mission to study Saturn's system in July 2004. Two tour extensions followed: a two-year Equinox Mission beginning in July 2008 and a seven-year Solstice Mission starting in September 2010. This paper highlights Cassini maneuver activities from June 2010 through June 2011, covering the transition from the Equinox to Solstice Mission. This interval included 38 scheduled maneuvers, nine targeted Titan flybys, three targeted Enceladus flybys, and one close Rhea flyby. In addition, beyond the demanding nominal navigation schedule, numerous unforeseen challenges further complicated maneuver operations. These challenges will be discussed in detail.

  4. Trajectories to the outer planets using aero-gravity assist flybys of Venus and Mars

    Science.gov (United States)

    Bender, David F.

    1992-01-01

    The trajectory concept used here is to flyby Venus and then Mars with moderately high speeds expecting to use both gravity and aeroassisted (wave rider) turns in the atmospheres of the planets in order to form fast trajectories to the planets beyond Jupiter. The first part of the paper contains a description of the development of earth-Venus-Mars trajectories yielding the required speeds at Mars in the interval 2001 to 2015. The second part consists in identifying cases in which Mars is at the proper longitude for each target and obtaining trajectories. Trajectories to Saturn, Uranus, Neptune, and Pluto have been found.

  5. The ESA JUICE mission: the Science and the Science Operations

    Science.gov (United States)

    Lorente, Rosario; Altobelli, Nicolas; Vallat, Claire; Munoz, Claudio; Andres, Rafael; Cardesin, Alejandro; Witasse, Olivier; Erd, Christian

    2017-04-01

    sensing capabilities via energetic neutrals, a magnetometer (J-MAG) and a radio and plasma wave instrument (RPWI), including electric fields sensors and a Langmuir probe. An experiment (PRIDE) using ground-based Very Long Baseline Interferometry (VLBI) will support precise determination of the spacecraft state vector with the focus at improving the ephemeris of the Jovian system. The current baseline assumes a launch in May 2022. Following an interplanetary cruise of 7.6 years, the Jupiter orbit insertion will take place in October 2029. The Jupiter tour will consists of 50 orbits around the giant planet, and will include two flybys of Europa at 400 km altitude, eleven flybys of Ganymede, and thirteen flybys of Callisto, as close as 200 km altitude. The last part of the mission will be the orbital phase around Ganymede, for about 10 months, where the spacecraft will be placed into a series of elliptical and circular orbits, the latest one at 500 km altitude. The end of mission is currently planned as an impact on Ganymede in June 2033. The ESA Science Operation Centre (SOC) is in charge of implementing the science operations of the JUICE mission. The SOC aims at supporting the Science Working Team (SWT) and the Science Working Groups (WGs) performing studies of science operation feasibility and coverage analysis during the mission development phase until launch, high level science planning during the cruise phase, and routine consolidation of instrument pointing and commanding timeline during the nominal science phase. This presentation will provide the latest information on the status of the project, and on the designed spacecraft trajectory in the Jovian system. It will focus on the science operational scenario of the two Europa flybys of the mission, and on the overall science return. References: [1] JUICE Definition Study Report, Reference ESA/SRE(2014)1,2014. http://sci.esa.int/juice/54994-juice-definition-study-report/ [2] Grasset, O., et al., JUpiter ICy moons

  6. Juno's first glimpse of Jupiter's complexity

    Science.gov (United States)

    Bolton, Scott; Levin, Steven; Bagenal, Fran

    2017-08-01

    Preliminary results from NASA's Juno mission are presented in this special issue of Geophysical Research Letters. The data were gathered by nine scientific instruments as the Juno spacecraft approached Jupiter on the dawn flank, was inserted into Jupiter orbit on 4 July 2016, and made the first polar passes close to the planet. The first results hint that Jupiter may not have a distinct core, indicate puzzling deep atmospheric convection, and reveal complex small-scale structure in the magnetic field and auroral processes that are distinctly different from those at Earth.

  7. Pioneer fly-by of Saturn and its rings

    Science.gov (United States)

    Gehrels, T.; Esposito, L.

    1981-01-01

    Results acquired by the imaging photopolarimeter on board Pioneer 11 during the spacecraft fly-by of Saturn and its rings on September 1, 1979 are reviewed. Analysis of the broadband photometry and polarimetry obtained of the Saturn atmosphere has been used to determine a cloud top height of 300 mb and a scale height of the aerosol distribution about 1/4 that of the ambient gas, and to point out differences between the forward scattering and belt and zone characteristics of the Saturn and Jupiter atmospheres. Images of Saturn's rings have been used to derive a profile of ring optical depth between 1.22 and 2.35 Saturn radii, and reveal new divisions and thin rings and azimuthal variations in the brightness of the A ring not observable from earth. Linear polarization observations of Titan in red and blue light reveal that the aerosols near the top of the atmosphere have radii less than about 0.09 micron and that the optical thickness of the small aerosol layer is about 0.6 above an effectively depolarizing surface, and indicate radii of 2845 + or - 25 km and 2880 + or - 22 km in red and blue light, respectively. Earth-based and spacecraft data are consistent with the formation of rings structures as a result of Poynting-Robertson drag and gravitational satellite resonances with the original ice and rock particles.

  8. The Juno Mission

    Science.gov (United States)

    Bolton, S. J.

    2015-12-01

    The Juno mission is the second mission in NASA's New Frontiers program. Launched in August 2011, Juno arrives at Jupiter in July 2016. Juno science goals include the study of Jupiter's origin, interior structure, deep atmosphere, aurora and magnetosphere. Jupiter's formation is fundamental to the evolution of our solar system and to the distribution of volatiles early in the solar system's history. Juno's measurements of the abundance of Oxygen and Nitrogen in Jupiter's atmosphere, and the detailed maps of Jupiter's gravity and magnetic field structure will constrain theories of early planetary development. Juno's orbit around Jupiter is a polar elliptical orbit with perijove approximately 5000 km above the visible cloud tops. The payload consists of a set of microwave antennas for deep sounding, magnetometers, gravity radio science, low and high energy charged particle detectors, electric and magnetic field radio and plasma wave experiment, ultraviolet imaging spectrograph, infrared imager and a visible camera. The Juno design enables the first detailed investigation of Jupiter's interior structure, and deep atmosphere as well as the first in depth exploration of Jupiter's polar magnetosphere. The Juno mission design, science goals, and measurements related to the origin of Jupiter will be presented.

  9. Transiting exoplanets from the CoRoT space mission XVII. The hot Jupiter CoRoT-17b: a very old planet

    CERN Document Server

    Csizmadia, Sz; Deleuil, M; Cabrera, J; Fridlund, M; Gandolfi, D; Aigrain, S; Alonso, R; Almenara, J M; Auvergne, M; Baglin, A; Barge, P; Bonomo, A S; Borde, P; Bouchy, F; Bruntt, H; Carone, L; Carpano, S; Cavarroc, C; Cochran, W; Deeg, H J; Diaz, R F; Dvorak, R; Endl, M; Erikson, A; Ferraz-Mello, S; Fruth, Th; Gazzano, J C; Gillon, M; Guenther, E W; Guillot, T; Hatzes, A; Havel, M; Hebrard, G; Jehin, E; Jorda, L; Leger, A; Llebaria, A; Lammer, H; Lovis, C; MacQueen, P J; Mazeh, T; Ollivier, M; Paetzold, M; Queloz, D; Rauer, H; Rouan, D; Santerne, A; Schneider, J; Tingley, B; Titz-Weider, R; Wuchterl, G

    2011-01-01

    We report on the discovery of a hot Jupiter-type exoplanet, CoRoT-17b, detected by the CoRoT satellite. It has a mass of $2.43\\pm0.30$\\Mjup and a radius of $1.02\\pm0.07$\\Rjup, while its mean density is $2.82\\pm0.38$ g/cm$^3$. CoRoT-17b is in a circular orbit with a period of $3.7681\\pm0.0003$ days. The host star is an old ($10.7\\pm1.0$ Gyr) main-sequence star, which makes it an intriguing object for planetary evolution studies. The planet's internal composition is not well constrained and can range from pure H/He to one that can contain $\\sim$380 earth masses of heavier elements.

  10. Jupiter internal structure: the effect of different equations of state

    CERN Document Server

    Miguel, Yamila; Fayon, Lucile

    2016-01-01

    Heavy elements, even though its smaller constituent, are crucial to understand Jupiter formation history. Interior models are used to determine the amount of heavy elements in Jupiter interior, nevertheless this range is still subject to degeneracies due to uncertainties in the equations of state. Prior to Juno mission data arrival, we present Jupiter optimized calculations exploring the effect of different model parameters in the determination of Jupiter's core and heavy element's mass. We perform comparisons between equations of state published recently. The interior model of Jupiter is calculated from the equations of hydrostatic equilibrium, mass and energy conservation, and energy transport. The mass of the core and heavy elements is adjusted to match Jupiter's observational constrains radius and gravitational moments. We show that the determination of Jupiter interior structure is tied to the estimation of its gravitational moments and the accuracy of equations of state of hydrogen, helium and heavy ele...

  11. Mission to the Trojan Asteroids: lessons learned during a JPL Planetary Science Summer School mission design exercise

    CERN Document Server

    Diniega, Serina; Balcerski, Jeffrey; Carande, Bryce; Diaz-Silva, Ricardo A; Fraeman, Abigail A; Guzewich, Scott D; Hudson, Jennifer; Nahm, Amanda L; Potter-McIntyre, Sally; Route, Matthew; Urban, Kevin D; Vasisht, Soumya; Benneke, Bjoern; Gil, Stephanie; Livi, Roberto; Williams, Brian; Budney, Charles J; Lowes, Leslie L; 10.1016/j.pss.2012.11.011

    2013-01-01

    The 2013 Planetary Science Decadal Survey identified a detailed investigation of the Trojan asteroids occupying Jupiter's L4 and L5 Lagrange points as a priority for future NASA missions. Observing these asteroids and measuring their physical characteristics and composition would aid in identification of their source and provide answers about their likely impact history and evolution, thus yielding information about the makeup and dynamics of the early Solar System. We present a conceptual design for a mission to the Jovian Trojan asteroids: the Trojan ASteroid Tour, Exploration, and Rendezvous (TASTER) mission, that is consistent with the NASA New Frontiers candidate mission recommended by the Decadal Survey and the final result of the 2011 NASA-JPL Planetary Science Summer School. Our proposed mission includes visits to two Trojans in the L4 population: a 500 km altitude fly-by of 1999 XS143, followed by a rendezvous with and detailed observations of 911 Agamemnon at orbital altitudes of 1000 - 100 km over ...

  12. The meteorology of Jupiter

    Science.gov (United States)

    Ingersoll, A. P.

    1976-01-01

    From the point of view of meteorology the most important differences between Jupiter and the earth are related to the fact that Jupiter has an appreciable internal energy source and probably lacks a solid surface. The composition and vertical structure of the Jovian atmosphere is considered along with the composition of Jovian cloud particles, turbulence in Jupiter's atmosphere, data on the horizontal structure and motions of the atmosphere, and questions related to the longevity of Jupiter's clouds. Attention is given to the barotropic characteristics of Jupiter's atmosphere, the radiation balance in the atmosphere of the earth and of Jupiter, and studies of the Great Red Spot.

  13. Transiting exoplanets from the CoRoT space mission - XIX. CoRoT-23b: a dense hot Jupiter on an eccentric orbit

    CERN Document Server

    Rouan, D; Moutou, C; Deleuil, M; Fridlund, M; Ofir, A; Havel, M; Aigrain, S; Alonso, R; Auvergne, M; Baglin, A; Barge, P; Bonomo, A; Bordé, P; Bouchy, F; Cabrera, J; Cavarroc, C; Csizmadia, Sz; Deeg, H; Diaz, R F; Dvorak, R; Erikson, A; Ferraz-Mello, S; Gandolfi, D; Gillon, M; Guillot, T; Hatzes, A; Hébrard, G; Jorda, L; Léger, A; Llebaria, A; Lammer, H; Lovis, C; Mazeh, T; Ollivier, M; Pätzold, M; Queloz, D; Rauer, H; Samuel, B; Santerne, A; Schneider, J; Tingley, B; Wuchterl, G

    2011-01-01

    We report the detection of CoRoT-23b, a hot Jupiter transiting in front of its host star with a period of 3.6314 \\pm 0.0001 days. This planet was discovered thanks to photometric data secured with the CoRoT satellite, combined with spectroscopic radial velocity (RV) measurements. A photometric search for possible background eclipsing binaries conducted at CFHT and OGS concluded with a very low risk of false positives. The usual techniques of combining RV and transit data simultaneously were used to derive stellar and planetary parameters. The planet has a mass of Mp = 2.8 \\pm 0.3 MJup, a radius of Rpl = 1.05 \\pm 0.13 RJup, a density of \\approx 3 g cm-3. RV data also clearly reveal a non zero eccentricity of e = 0.16 \\pm 0.02. The planet orbits a mature G0 main sequence star of V =15.5 mag, with a mass M\\star = 1.14 \\pm 0.08 M\\odot, a radius R\\star = 1. 61 \\pm 0.18 R\\odot and quasi-solar abundances. The age of the system is evaluated to be 7 Gyr, not far from the transition to subgiant, in agreement with the r...

  14. Transiting exoplanets from the CoRoT space mission. XX. CoRoT-18b: a massive hot jupiter on a prograde, nearly aligned orbit

    CERN Document Server

    Hebrard, G; Alonso, R; Fridlund, M; Ofir, A; Aigrain, S; Guillot, T; Almenara, J M; Auvergne, M; Baglin, A; Barge, P; Bonomo, A S; Borde, P; Bouchy, F; Cabrera, J; Carone, L; Carpano, S; Cavarroc, C; Csizmadia, Sz; Deeg, H J; Deleuil, M; Diaz, R F; Dvorak, R; Erikson, A; Ferraz-Mello, S; Gandolfi, D; Gibson, N; Gillon, M; Guenther, E; Hatzes, A; Havel, M; Jorda, L; Lammer, H; Leger, A; Llebaria, A; Mazeh, T; Moutou, C; Ollivier, M; Parviainen, H; Patzold, M; Queloz, D; Rauer, H; Rouan, D; Santerne, A; Schneider, J; Tingley, B; Wuchterl, G

    2011-01-01

    We report the detection of CoRoT-18b, a massive hot jupiter transiting in front of its host star with a period of 1.9000693 +/- 0.0000028 days. This planet was discovered thanks to photometric data secured with the CoRoT satellite combined with spectroscopic and photometric follow-up ground-based observations. The planet has a mass M_p = 3.47 +/- 0.38 M_Jup, a radius R_p = 1.31 +/- 0.18 R_Jup, and a density rho_p = 2.2 +/- 0.8 g/cm3. It orbits a G9V star with a mass M_* = 0.95 +/- 0.15 M_Sun, a radius R_* = 1.00 +/- 0.13 R_Sun, and a rotation period P_rot = 5.4 +/- 0.4 days. The age of the system remains uncertain, stellar evolution models pointing either to a few tens Ma or several Ga, while gyrochronology and lithium abundance point towards ages of a few hundred Ma. This mismatch potentially points to a problem in our understanding of the evolution of young stars, with possible significant implications for stellar physics and the interpretation of inferred sizes of exoplanets around young stars. We detected...

  15. Can Terrestrial Planets Form in Hot-Jupiter Systems?

    CERN Document Server

    Fogg, Martyn J

    2007-01-01

    Models of terrestrial planet formation in the presence of a migrating giant planet have challenged the notion that hot-Jupiter systems lack terrestrial planets. We briefly review this issue and suggest that hot-Jupiter systems should be prime targets for future observational missions designed to detect Earth-sized and potentially habitable worlds.

  16. New Horizons Imaging of Jupiter's Main Ring

    Science.gov (United States)

    Throop, Henry B.; Showalter, Mark Robert; Dones, Henry C. Luke; Hamilton, D. P.; Weaver, Harold A.; Cheng, Andrew F.; Stern, S. Alan; Young, Leslie; Olkin, Catherine B.; New Horizons Science Team

    2016-10-01

    New Horizons took roughly 520 visible-light images of Jupiter's ring system during its 2007 flyby, using the spacecraft's Long-Range Reconnaissance Imager (LORRI). These observations were taken over nine days surrounding Jupiter close-approach. They span a range in distance of 30 - 100 RJ, and a phase angle range of 20 - 174 degrees. The highest resolution images -- more than 200 frames -- were taken at a resolution approaching 20 km/pix.We will present an analysis of this dataset, much of which has not been studied in detail before. Our results include New Horizons' first quantitative measurements of the ring's intrinsic brightness and variability. We will also present results on the ring's azimuthal and radial structure. Our measurements of the ring's phase curve will be used to infer properties of the ring's dust grains.Our results build on the only previous analysis of the New Horizons Jupiter ring data set, presented in Showalter et al (2007, Science 318, 232-234), which detected ring clumps and placed a lower limit on the population of undetected ring-moons.This work was supported by NASA's OPR program.

  17. Io in Front of Jupiter

    Science.gov (United States)

    2000-01-01

    Jupiter's four largest satellites, including Io, the golden ornament in front of Jupiter in this image from NASA's Cassini spacecraft, have fascinated Earthlings ever since Galileo Galilei discovered them in 1610 in one of his first astronomical uses of the telescope.Images from Cassini that will be released over the next several days capture each of the four Galilean satellites in their orbits around the giant planet.This true-color composite frame, made from narrow angle images taken on Dec. 12, 2000, captures Io and its shadow in transit against the disk of Jupiter. The distance of the spacecraft from Jupiter was 19.5 million kilometers (12.1 million miles). The image scale is 117 kilometers (73 miles) per pixel.The entire body of Io, about the size of Earth's Moon, is periodically flexed as it speeds around Jupiter and feels, as a result of its non-circular orbit, the periodically changing gravitational pull of the planet. The heat arising in Io's interior from this continual flexure makes it the most volcanically active body in the solar system, with more than 100 active volcanoes. The white and reddish colors on its surface are due to the presence of different sulfurous materials. The black areas are silicate rocks.Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.

  18. Planetary geometry handbook: Jupiter positional data, 1985 - 2020, volume 4

    Science.gov (United States)

    Sergeyevsky, A. B.; Snyder, G. C.; Paulson, B. L.; Cunniff, R. A.

    1983-01-01

    Graphical data necessary for the analysis of planetary exploration missions to Jupiter are presented. Positional and geometric information spanning the time period from 1985 through 2020 is provided. The data and their usage are explained.

  19. OSIRIS-REx Asterod Sample Return Mission

    Science.gov (United States)

    Nakamura-Messinger, Keiki; Connolly, Harold C. Jr.; Messenger, Scott; Lauretta, Dante S.

    2017-01-01

    OSIRIS-REx is NASA's third New Frontiers Program mission, following New Horizons that completed a flyby of Pluto in 2015 and the Juno mission to Jupiter that has just begun science operations. The OSIRIS-REx mission's primary objective is to collect pristine surface samples of a carbonaceous asteroid and return to Earth for analysis. Carbonaceous asteroids and comets are 'primitive' bodies that preserved remnants of the Solar System starting materials and through their study scientists can learn about the origin and the earliest evolution of the Solar System. The OSIRIS-REx spacecraft was successfully launched on September 8, 2016, beginning its seven year journey to asteroid 101955 Bennu. The robotic arm will collect 60-2000 grams of material from the surface of Bennu and will return to Earth in 2023 for worldwide distribution by the Astromaterials Curation Facility at NASA Johnson Space Center. The name OSIRIS-REx embodies the mission objectives (1) Origins: Return and analyze a sample of a carbonaceous asteroid, (2) Spectral Interpretation: Provide ground-truth for remote observation of asteroids, (3) Resource Identification: Determine the mineral and chemical makeup of a near-Earth asteroid (4) Security: Measure the non-gravitational that changes asteroidal orbits and (5) Regolith Explorer: Determine the properties of the material covering an asteroid surface. Asteroid Bennu may preserve remnants of stardust, interstellar materials and the first solids to form in the Solar System and the molecular precursors to the origin of life and the Earth's oceans. Bennu is a potentially hazardous asteroid, with an approximately 1 in 2700 chance of impacting the Earth late in the 22nd century. OSIRIS-REx collects from Bennu will help formulate the types of operations and identify mission activities that astronauts will perform during their expeditions. Such information is crucial in preparing for humanity's next steps beyond low Earthy orbit and on to deep space

  20. Jupiter's radiation belts and atmosphere

    Science.gov (United States)

    De Pater, I.; Dames, H. A. C.

    1979-01-01

    Maps and stripscans of the radio emission from Jupiter were made during the Pioneer 10 flyby in December 1973 at wavelengths of 6 cm, 21 cm, and 50 cm using the Westerbork telescope in the Netherlands. With this instrument the disk of the planet was resolved at 6 and 21 cm. The pictures are averaged over 15 deg of Jovian longitude. At 21 cm the stripscans clearly show the existence of a 'hot region' in the radiation belts at a System III longitude (1965.0) of 255 + or - 10 deg. Its flux is about 9% of the total nonthermal flux, and it has a volume emissivity enhanced by a factor of about 1.6 with respect to the general radiation belts. The temperature of the thermal disk at 21 cm appears to be 290 + or - 20 K. This is likely due to a high ammonia mixing ratio in the atmosphere, a factor of 4-5 larger than the expected solar value of 0.00015.

  1. Measuring Jupiter's water abundance by Juno: the link between interior and formation models

    CERN Document Server

    Helled, Ravit

    2014-01-01

    The JUNO mission to Jupiter is planned to measure the water abundance in Jupiter's atmosphere below the cloud layer. This measurement is important because it can be used to reveal valuable information on Jupiter's origin and its composition. In this paper we discuss the importance of this measurement, the challenges in its interpretation, and address how it can be connected to interior and formation models of Jupiter.

  2. A Discovery Mission to Determine the Interior Structure of Gas- and Ice-Giants

    Science.gov (United States)

    Hofstadter, Mark D.; Murphy, N.; Matousek, S.; Bairstow, S.; Maiwald, F.; Jeffries, S.; Schmider, F.; Guillot, T.

    2013-10-01

    The Ice Giants (Uranus and Neptune) are fundamentally different than the better-known Gas Giants (Jupiter and Saturn). Ice Giants are roughly 65% water by mass, compared to Gas Giants which are ~95% hydrogen and helium. Knowing the interior structure of both types of planets is a key measurement needed to advance our understanding of the formation and evolution of planetary systems, particularly in light of recent findings that Ice Giants are far more abundant in our galaxy than Gas Giants (Borucki et al., ApJ 2011). In the past, gravity measurements from spacecraft in low orbits have been the primary way to tease out information on interior structure. A new approach, Doppler imaging, can provide detailed information on interior structure from great distances (Gaulme et al., A&A 2011). A planetary Doppler Imager (DI) builds on the well-established fields of helio- and stellar-seismology, which have revolutionized our understanding of the interior of stars. The great advantage of a DI is that its observations do not require the spacecraft to enter orbit. We have designed a Discovery mission around such an instrument to determine the interior structures of Jupiter and Uranus during flybys of each planet. The data collected at Jupiter (after a 1.5 year flight) will compliment observations to be made by the Juno spacecraft in 2016, creating a much more accurate picture of the interior than is possible from the gravity technique alone. Roughly 6.5 years after the Jupiter flyby, DI measurements of Uranus will open that planet's interior for the first time. At both planets, measurements of the interior structure are made over a 4-month period centered on closest approach (CA), but with a ~1 week gap at CA when the planet is too close for whole-disk imaging. This allows other measurements to be made at that time, such as of small-scale weather features or satellites. We note that the DI technique, while enabling a Discovery-class mission, can also benefit larger missions

  3. Europa Planetary Protection for Juno Jupiter Orbiter

    Science.gov (United States)

    Bernard, Douglas E.; Abelson, Robert D.; Johannesen, Jennie R.; Lam, Try; McAlpine, William J.; Newlin, Laura E.

    2010-01-01

    NASA's Juno mission launched in 2011 and will explore the Jupiter system starting in 2016. Juno's suite of instruments is designed to investigate the atmosphere, gravitational fields, magnetic fields, and auroral regions. Its low perijove polar orbit will allow it to explore portions of the Jovian environment never before visited. While the Juno mission is not orbiting or flying close to Europa or the other Galilean satellites, planetary protection requirements for avoiding the contamination of Europa have been taken into account in the Juno mission design.The science mission is designed to conclude with a deorbit burn that disposes of the spacecraft in Jupiter's atmosphere. Compliance with planetary protection requirements is verified through a set of analyses including analysis of initial bioburden, analysis of the effect of bioburden reduction due to the space and Jovian radiation environments, probabilistic risk assessment of successful deorbit, Monte-Carlo orbit propagation, and bioburden reduction in the event of impact with an icy body.

  4. Management experience of an international venture in space The Ulysses mission

    Science.gov (United States)

    Yoshida, Ronald Y.; Meeks, Willis G.

    1986-01-01

    The management of the Ulysses project, a probe which will fly a solar polar orbit, is described. The 5-yr mission will feature a flyby of Jupiter to deflect the spacecraft into a high-inclination orbit. Data on the solar corona, solar wind, the sun-wind interface, the heliospheric magnetic field, solar and nonsolar cosmic rays, etc., will be gathered as a function of the solar latitude. NASA will track and control the probe with the Deep Space Network. JPL provides project management for NASA while the Directorate of Scientific Programs performs ESA management functions. The DOE will provide a radioisotope thermoelectric generator while NASA and ESA each supply half the scientific payload. A NASA-ESA Joint Working Group meets about twice per year to monitor the project and discuss the technical and scientific requirements. Safety issues and measures which are being addressed due to the presence of the Pu-238 heat source for the RTG are discussed.

  5. Northern Belt of Jupiter

    Science.gov (United States)

    2000-01-01

    makes it difficult to see into lower layers at all. The bright regions are generally free of high stratospheric hazes.A small bright spot is visible near the center of each panel. Similar spots have been imaged in turbulent regions by the Galileo spacecraft, and they appear to be very energetic convective storms that move heat from the interior of Jupiter to higher altitudes. These storms are expected to penetrate to great heights, and so it is not surprising to see the storm in the first three images, which probe atmospheric altitudes from the lower to the upper troposphere. What is surprising is the appearance of the spot in the ultraviolet image. Higher resolution, time-lapse images to be captured by Cassini in coming weeks will shed more light on these spectacular features.Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.

  6. High Latitude Mottling on Jupiter

    Science.gov (United States)

    2000-01-01

    The familiar banded appearance of Jupiter at low and middle latitudes gradually gives way to a more mottled appearance at high latitudes in this striking true color image taken Dec. 13, 2000, by NASA's Cassini spacecraft.The intricate structures seen in the polar region are clouds of different chemical composition, height and thickness. Clouds are organized by winds, and the mottled appearance in the polar regions suggests more vortex-type motion and winds of less vigor at higher latitudes.The cause of this difference is not understood. One possible contributor is that the horizontal component of the Coriolis force, which arises from the planet's rotation and is responsible for curving the trajectories of ocean currents and winds on Earth, has its greatest effect at high latitudes and vanishes at the equator. This tends to create small, intense vortices at high latitudes on Jupiter. Another possibility may lie in that fact that Jupiter overall emits nearly as much of its own heat as it absorbs from the Sun, and this internal heat flux is very likely greater at the poles. This condition could lead to enhanced convection at the poles and more vortex-type structures. Further analysis of Cassini images, including analysis of sequences taken over a span of time, should help us understand the cause of equator-to-pole differences in cloud organization and evolution.By the time this picture was taken, Cassini had reached close enough to Jupiter to allow the spacecraft to return images with more detail than what's possible with the planetary camera on NASA's Earth-orbiting Hubble Space Telescope. The resolution here is 114 kilometers (71 miles) per pixel. This contrast-enhanced, edge-sharpened frame was composited from images take at different wavelengths with Cassini's narrow-angle camera, from a distance of 19 million kilometers (11.8 million miles). The spacecraft was in almost a direct line between the Sun and Jupiter, so the solar illumination on Jupiter is almost full

  7. The First Kepler Mission Planet Confirmed With The Hobby-Eberly Telescope: Kepler-15b, a Hot Jupiter Enriched In Heavy Elements

    CERN Document Server

    Endl, Michael; Cochran, William D; Brugamyer, Erik; Buchhave, Lars A; Rowe, Jason; Lucas, Phillip; Issacson, Howard; Bryson, Steve; Howell, Steve B; Fortney, Jonathan J; Hansen, Terese; Borucki, William J; Caldwell, Douglas; Christiansen, Jessie L; Ciardi, David R; Demory, Brice-Olivier; Everett, Mark; Ford, Eric B; Haas, Michael R; Holman, Matthew J; Horch, Elliot; Jenkins, Jon M; Koch, David J; Lissauer, Jack J; Machalek, Pavel; Still, Martin; Welsh, William F; Sanderfer, Dwight T; Seader, Shawn E; Smith, Jeffrey C; Thompson, Susan E; Twicken, Joseph D

    2011-01-01

    We report the discovery of Kepler-15b, a new transiting exoplanet detected by NASA's Kepler mission. The transit signal with a period of 4.94 days was detected in the quarter 1 (Q1) Kepler photometry. For the first time, we have used the High-Resolution-Spectrograph (HRS) at the Hobby-Eberly Telescope (HET) to determine the mass of a Kepler planet via precise radial velocity (RV) measurements. The 24 HET/HRS radial velocities (RV) and 6 additional measurements from the FIES spectrograph at the Nordic Optical Telescope (NOT) reveal a Doppler signal with the same period and phase as the transit ephemeris. We used one HET/HRS spectrum of Kepler-15 taken without the iodine cell to determine accurate stellar parameters. The host star is a metal-rich ([Fe/H]=0.36+/-0.07) G-type main sequence star with T_eff=5515+/-124 K. The amplitude of the RV-orbit yields a mass of the planet of 0.66+/-0.1 M_Jup. The planet has a radius of 0.96+/-0.06 R_Jup and a mean bulk density of 0.9+/-0.2 g/cm^3. The planetary radius resides...

  8. Jupiter Magnetospheric Orbiter and Trojan Asteroid Explorer in EJSM

    Science.gov (United States)

    Sasaki, Sho; Fujimoto, Masaki; Yano, Hajime; Takashima, Takeshi; Kasaba, Yasumasa; Funase, Ryu; Tsuda, Yuichi; Kawaguchi, Junichiro; Kawakatsu, Yasuhiro; Mori, Osamu; Morimoto, Mutsuko; Yoshida, Fumi; Takato, Naruhisa

    The international mission to explore the Jovian system is planned as Europa Jupiter System Mission (EJSM) aiming at the launch in 2020. EJSM consists of (1) the Jupiter Europa Orbiter (JEO) by NASA, (2) the Jupiter Ganymede Orbiter (JGO) by ESA, and (3) the Jupiter Magnetospheric Orbiter (JMO) studied by JAXA (Japan Aerospace Exploration Agency). In February 2009, NASA and ESA decided to continue the study of EJSM as a candidate of the outer solar system mission. In JAXA, a mission plan combining Trojan asteroid explorer with JMO started. According to the mission plan, as the main spacecraft flies by Jupiter, it will deploy the JMO satellite around Jupiter. Then the main will target one (or two) Trojan asteroids. JMO is a spin-stabilized satellite which will have magnetometers, low-energy plasma spectrome-ters, medium energy particle detectors, energetic particle detectors, electric field / plasma wave instruments, an ENA imager, an EUV spectrometer, and a dust detector. Collaborating with plasma instruments on board JEO and JGO, JMO will investigate the fast-rotating huge mag-netosphere to clarify the energy procurement from the rotation of Jupiter to the magnetosphere and to clarify the interaction between the solar wind and the magnetosphere. JAXA started the study of a solar power sail for deep space explorations. In addition to the function of a solar sail (photon propulsion), the solar power sail system has very efficient ion engines where electric power is produced solar panels within the sail. Currently we are studying a mission to Jupiter and Trojan asteroids using a large (100m-scale) solar power sail that can transfer large payload as far as Jupiter. Trojan asteroids, which orbit around Jupiter's Lagrangian points, are primitive bodies with information of the early solar system as well as raw solid materials of Jovian system. Proposed instruments for the Trojan spacecraft are cameras, IR spectrometers, XRS, a laser altimeter, and a small surface rover

  9. KEPLER-15b: A HOT JUPITER ENRICHED IN HEAVY ELEMENTS AND THE FIRST KEPLER MISSION PLANET CONFIRMED WITH THE HOBBY-EBERLY TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Endl, Michael; MacQueen, Phillip J.; Cochran, William D. [McDonald Observatory, University of Texas at Austin, Austin, TX 78712 (United States); Brugamyer, Erik J. [Astronomy Department, University of Texas at Austin, Austin, TX 78712 (United States); Buchhave, Lars A. [Niels Bohr Institute, University of Copenhagen, Denmark Centre for Star and Planet Formation, University of Copenhagen (Denmark); Rowe, Jason [SETI Institute, Moffett Field, CA 94035 (United States); Lucas, Phillip [Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB (United Kingdom); Isaacson, Howard [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Bryson, Steve; Howell, Steve B.; Borucki, William J.; Caldwell, Douglas; Christiansen, Jessie L.; Haas, Michael R. [NASA-Ames Research Center, Moffett Field, CA 94035 (United States); Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Hansen, Terese [Niels Bohr Institute, University of Copenhagen (Denmark); Ciardi, David R. [NASA Exoplanet Science Institute/Caltech, Pasadena, CA 91125 (United States); Demory, Brice-Olivier [Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Everett, Mark [NOAO, 950 N. Cherry Ave., Tucson, AZ 85719 (United States); Ford, Eric B. [Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32111 (United States); and others

    2011-11-01

    We report the discovery of Kepler-15b (KOI-128), a new transiting exoplanet detected by NASA's Kepler mission. The transit signal with a period of 4.94 days was detected in the quarter 1 (Q1) Kepler photometry. For the first time, we have used the High Resolution Spectrograph (HRS) at the Hobby-Eberly Telescope (HET) to determine the mass of a Kepler planet via precise radial velocity (RV) measurements. The 24 HET/HRS RVs and 6 additional measurements from the Fibre-fed Echelle Spectrograph spectrograph at the Nordic Optical Telescope reveal a Doppler signal with the same period and phase as the transit ephemeris. We used one HET/HRS spectrum of Kepler-15 taken without the iodine cell to determine accurate stellar parameters. The host star is a metal-rich ([Fe/H] = 0.36 {+-} 0.07) G-type main-sequence star with T{sub eff} = 5515 {+-} 124 K. The semi-amplitude K of the RV orbit is 78.7{sup +8.5}{sub -9.5} m s{sup -1}, which yields a planet mass of 0.66 {+-} 0.1 M{sub Jup}. The planet has a radius of 0.96 {+-} 0.06 R{sub Jup} and a mean bulk density of 0.9 {+-} 0.2 g cm{sup -3}. The radius of Kepler-15b is smaller than the majority of transiting planets with similar mass and irradiation level. This suggests that the planet is more enriched in heavy elements than most other transiting giant planets. For Kepler-15b we estimate a heavy element mass of 30-40 M{sub Circled-Plus }.

  10. Tachyonic Cherenkov emission from Jupiter's radio electrons

    Energy Technology Data Exchange (ETDEWEB)

    Tomaschitz, Roman, E-mail: tom@geminga.org

    2013-12-17

    Tachyonic Cherenkov radiation from inertial relativistic electrons in the Jovian radiation belts is studied. The tachyonic modes are coupled to a frequency-dependent permeability tensor and admit a negative mass-square, rendering them superluminal and dispersive. The superluminal radiation field can be cast into Maxwellian form, using 3D field strengths and inductions, and the spectral densities of tachyonic Cherenkov radiation are derived. The negative mass-square gives rise to a longitudinal flux component. A spectral fit to Jupiter's radio spectrum, inferred from ground-based observations and the Cassini 2001 fly-by, is performed with tachyonic Cherenkov flux densities averaged over a thermal electron population.

  11. Radiation Environment for the Jupiter Europa Orbiter

    Science.gov (United States)

    Jun, Insoo

    2008-09-01

    One of the major challenges for the Jupiter Europa Orbiter (JEO) mission would be that the spacecraft should be designed to survive an intense radiation environment expected at Jupiter and Europa. The proper definition of the radiation environments is the important first step, because it could affect almost every aspects of mission and spacecraft design. These include optimizing the trajectory to minimize radiation exposure, determining mission lifetime, selecting parts, materials, detectors and sensors, shielding design, etc. The radiation environments generated for the 2008 JEO study will be covered, emphasizing the radiation environment mainly responsible for the total ionizing dose (TID) and displacement damage dose (DDD). The latest models developed at JPL will be used to generate the TID and DDD environments. Finally, the major radiation issues will be summarized, and a mitigation plan will be discussed.

  12. Observations of MeV electrons in Jupiter's innermost radiation belts and polar regions by the Juno radiation monitoring investigation: Perijoves 1 and 3

    DEFF Research Database (Denmark)

    Becker, Heidi N.; Santos-Costa, Daniel; Jørgensen, John Leif

    2017-01-01

    Juno's “Perijove 1” (27 August 2016) and “Perijove 3” (11 December 2016) flybys through the innermost region of Jupiter's magnetosphere (radial distances ... Investigation collected particle counts and noise signatures from penetrating high-energy particle impacts in images acquired by the Stellar Reference Unit and Advanced Stellar Compass star trackers, and the Jupiter Infrared Auroral Mapper infrared imager. This coordinated observation campaign sampled radiation...

  13. The Pluto system after the New Horizons flyby

    Science.gov (United States)

    Olkin, Catherine B.; Ennico, Kimberly; Spencer, John

    2017-09-01

    In July 2015, NASA's New Horizons mission performed a flyby of Pluto, revealing details about the geology, surface composition and atmospheres of this world and its moons that are unobtainable from Earth. With a resolution as small as 80 metres per pixel, New Horizons' images identified a large number of surface features, including a large basin filled with glacial ices that appear to be undergoing convection. Maps of surface composition show latitudinal banding, with non-volatile material dominating the equatorial region and volatile ices at mid- and polar latitudes. This pattern is driven by the seasonal cycle of solar insolation. New Horizons' atmospheric investigation found the temperature of Pluto's upper atmosphere to be much cooler than previously modelled. Images of forward-scattered sunlight revealed numerous haze layers extending up to 200 km from the surface. These discoveries have transformed our understanding of icy worlds in the outer Solar System, demonstrating that even at great distances from the Sun, worlds can have active geologic processes. This Review addresses our current understanding of the Pluto system and places it in context with previous investigations.

  14. Attitude Determination and Control Subsystem (ADCS) Preparations for the EPOXI Flyby of Comet Hartley 2

    Science.gov (United States)

    Luna, Michael E.; Collins, Steven M.

    2011-01-01

    On November 4, 2010 the former "Deep Impact" spacecraft, renamed "EPOXI" for its extended mission, flew within 700km of comet 103P/Hartley 2. In July 2005, the spacecraft had previously imaged a probe impact of comet Tempel 1. The EPOXI flyby was the fifth close encounter of a spacecraft with a comet nucleus and marked the first time in history that two comet nuclei were imaged at close range with the same suite of onboard science instruments. This challenging objective made the function of the attitude determination and control subsystem (ADCS) critical to the successful execution of the EPOXI flyby.As part of the spacecraft flyby preparations, the ADCS operations team had to perform meticulous sequence reviews, implement complex spacecraft engineering and science activities and perform numerous onboard calibrations. ADCS contributions included design and execution of 10 trajectory correction maneuvers, the science calibration of the two telescopic instruments, an in-flight demonstration of high-rate turns between Earth and comet point, and an ongoing assessment of reaction wheel health. The ADCS team was also responsible for command sequences that included updates to the onboard ephemeris and sun sensor coefficients and implementation of reaction wheel assembly (RWA) de-saturations.

  15. Titan's ionosphere in the magnetosheath: Cassini RPWS results during the T32 flyby

    Directory of Open Access Journals (Sweden)

    P. Garnier

    2009-11-01

    Full Text Available The Cassini mission has provided much information about the Titan environment, with numerous low altitude encounters with the moon being always inside the magnetosphere. The only encounter taking place outside the magnetopause, in the magnetosheath, occurred the 13 June 2007 (T32 flyby. This paper is dedicated to the analysis of the Radio and Plasma Wave investigation data during this specific encounter, in particular with the Langmuir probe, providing a detailed picture of the cold plasma environment and of Titan's ionosphere with these unique plasma conditions. The various pressure terms were also calculated during the flyby. The comparison with the T30 flyby, whose geometry was very similar to the T32 encounter but where Titan was immersed in the kronian magnetosphere, reveals that the evolution of the incident plasma has a significant influence on the structure of the ionosphere, with in particular a change of the exo-ionospheric shape. The electrical conductivities are given along the trajectory of the spacecraft and the discovery of a polar plasma cavity is reported.

  16. Attitude Determination and Control Subsystem (ADCS) Preparations for the EPOXI Flyby of Comet Hartley 2

    Science.gov (United States)

    Luna, Michael E.; Collins, Steven M.

    2011-01-01

    On November 4, 2010 the former "Deep Impact" spacecraft, renamed "EPOXI" for its extended mission, flew within 700km of comet 103P/Hartley 2. In July 2005, the spacecraft had previously imaged a probe impact of comet Tempel 1. The EPOXI flyby was the fifth close encounter of a spacecraft with a comet nucleus and marked the first time in history that two comet nuclei were imaged at close range with the same suite of onboard science instruments. This challenging objective made the function of the attitude determination and control subsystem (ADCS) critical to the successful execution of the EPOXI flyby.As part of the spacecraft flyby preparations, the ADCS operations team had to perform meticulous sequence reviews, implement complex spacecraft engineering and science activities and perform numerous onboard calibrations. ADCS contributions included design and execution of 10 trajectory correction maneuvers, the science calibration of the two telescopic instruments, an in-flight demonstration of high-rate turns between Earth and comet point, and an ongoing assessment of reaction wheel health. The ADCS team was also responsible for command sequences that included updates to the onboard ephemeris and sun sensor coefficients and implementation of reaction wheel assembly (RWA) de-saturations.

  17. An Overview of the Jupiter Europa Orbiter Concept's Europa Science Phase Orbit Design

    Science.gov (United States)

    Lock, Robert E.; Ludwinski, Jan M.; Petropoulos, Anastassios E.; Clark, Karla B.; Pappalardo, Robert T.

    2009-01-01

    Jupiter Europa Orbiter (JEO), the proposed NASA element of the proposed joint NASA-ESA Europa Jupiter System Mission (EJSM), could launch in February 2020 and conceivably arrive at Jupiter in December of 2025. The concept is to perform a multi-year study of Europa and the Jupiter system, including 30 months of Jupiter system science and a comprehensive Europa orbit phase of 9 months. This paper provides an overview of the JEO concept and describes the Europa Science phase orbit design and the related science priorities, model pay-load and operations scenarios needed to conduct the Europa Science phase. This overview is for planning and discussion purposes only.

  18. The Rosetta mission

    Science.gov (United States)

    Taylor, Matt; Altobelli, Nicolas; Martin, Patrick; Buratti, Bonnie J.; Choukroun, Mathieu

    2016-10-01

    The Rosetta Mission is the third cornerstone mission the ESA programme Horizon 2000. The aim of the mission is to map the comet 67-P/Churyumov-Gerasimenko by remote sensing, to examine its environment insitu and its evolution in the inner solar system. The lander Philae is the first device to land on a comet and perform in-situ science on the surface. Following its launch in March 2004, Rosetta underwent 3 Earth and 1 Mars flybys to achieve the correct trajectory to capture the comet, including flybys of asteroid on 2867 Steins and 21 Lutetia. For June 2011- January 2014 the spacecraft passed through a period of hibernation, due to lack of available power for full payload operation and following successful instrument commissioning, successfully rendezvoused with the comet in August 2014. Following an intense period of mapping and characterisation, a landing site for Philae was selected and on 12 November 2014, Philae was successfully deployed. Rosetta then embarked on the main phase of the mission, observing the comet on its way into and away from perihelion in August 2015. At the time of writing the mission is planned to terminate with the Rosetta orbiter impacting the comet surface on 30 September 2016. This presentation will provide a brief overview of the mission and its science. The first author is honoured to give this talk on behalf of all Rosetta mission science, instrument and operations teams, for it is they who have worked tirelessly to make this mission the success it is.

  19. Flyby Characterization of Lower-Degree Spherical Harmonics Around Small Bodies

    Science.gov (United States)

    Takahashi, Yu; Broschart, Stephen; Lantoine, Gregory

    2014-01-01

    Interest in studying small bodies has grown significantly in the last two decades, and there are a number of past, present, and future missions. These small body missions challenge navigators with significantly different kinds of problems than the planets and moons do. The small bodies' shape is often irregular and their gravitational field significantly weak, which make the designing of a stable orbit a complex dynamical problem. In the initial phase of spacecraft rendezvous with a small body, the determination of the gravitational parameter and lower-degree spherical harmonics are of crucial importance for safe navigation purposes. This motivates studying how well one can determine the total mass and lower-degree spherical harmonics in a relatively short time in the initial phase of the spacecraft rendezvous via flybys. A quick turnaround for the gravity data is of high value since it will facilitate the subsequent mission design of the main scientific observation campaign. We will present how one can approach the problem to determine a desirable flyby geometry for a general small body. We will work in the non-dimensional formulation since it will generalize our results across different size/mass bodies and the rotation rate for a specific combination of gravitational coefficients.

  20. Jupiter Environment Tool

    Science.gov (United States)

    Sturm, Erick J.; Monahue, Kenneth M.; Biehl, James P.; Kokorowski, Michael; Ngalande, Cedrick,; Boedeker, Jordan

    2012-01-01

    The Jupiter Environment Tool (JET) is a custom UI plug-in for STK that provides an interface to Jupiter environment models for visualization and analysis. Users can visualize the different magnetic field models of Jupiter through various rendering methods, which are fully integrated within STK s 3D Window. This allows users to take snapshots and make animations of their scenarios with magnetic field visualizations. Analytical data can be accessed in the form of custom vectors. Given these custom vectors, users have access to magnetic field data in custom reports, graphs, access constraints, coverage analysis, and anywhere else vectors are used within STK.

  1. Moons around Jupiter

    Science.gov (United States)

    2007-01-01

    The New Horizons Long Range Reconnaissance Imager (LORRI) took this photo of Jupiter at 20:42:01 UTC on January 9, 2007, when the spacecraft was 80 million kilometers (49.6 million miles) from the giant planet. The volcanic moon Io is to the left of the planet; the shadow of the icy moon Ganymede moves across Jupiter's northern hemisphere. Ganymede's average orbit distance from Jupiter is about 1 million kilometers (620,000 miles); Io's is 422,000 kilometers (262,000 miles). Both Io and Ganymede are larger than Earth's moon; Ganymede is larger than the planet Mercury.

  2. Deciphering Jupiter's atmospheric dynamics using the upcoming Juno gravity measurements

    Science.gov (United States)

    Kaspi, Yohai; Galanti, Eli

    2016-07-01

    This summer, the Juno spacecraft will arrive at Jupiter in course for close flybys of the planet, obtaining a high precision gravity spectrum of Jupiter. This data can be used to estimate the depth of Jupiter's observed cloud-level wind, and decipher the possible internal flows, that might be decoupled from the surface wind. In this talk, we discuss the Juno gravity experiment, and the possible outcomes with regard to the flows on Jupiter. We show several ways in which the gravity spectrum might be used to study the large scale flows: 1. measurements of the high order even harmonics which beyond J10 are dominated by the dynamics; 2. measurements of odd gravity harmonics which have no contribution from a static planet, and therefore are a pure signature of dynamics; 3. upper limits on the depth of the surface flow can be obtained by comparing low order even harmonics from dynamical models to the difference between the measured low order even harmonics and the largest possible values of a static planet; 4. direct latitudinally varying measurements of the gravity field exerted on the spacecraft. We will discuss how these methods may be applied given the expected sensitivities of the Juno gravity experiment. In addition, we present an inverse adjoint model, which allows given the gravity data, to infer the flows that produce it. This will allow, hopefully, to make significant progress in one of the longest-standing question in planetary atmospheric dynamics regarding the nature of the flows on the giant planets.

  3. Ultra-relativistic electrons in Jupiter's radiation belts.

    Science.gov (United States)

    Bolton, S J; Janssen, M; Thorne, R; Levin, S; Klein, M; Gulkis, S; Bastian, T; Sault, R; Elachi, C; Hofstadter, M; Bunker, A; Dulk, G; Gudim, E; Hamilton, G; Johnson, W T K; Leblanc, Y; Liepack, O; McLeod, R; Roller, J; Roth, L; West, R

    2002-02-28

    Ground-based observations have shown that Jupiter is a two-component source of microwave radio emission: thermal atmospheric emission and synchrotron emission from energetic electrons spiralling in Jupiter's magnetic field. Later in situ measurements confirmed the existence of Jupiter's high-energy electron-radiation belts, with evidence for electrons at energies up to 20[?]MeV. Although most radiation belt models predict electrons at higher energies, adiabatic diffusion theory can account only for energies up to around 20[?]MeV. Unambiguous evidence for more energetic electrons is lacking. Here we report observations of 13.8[?]GHz synchrotron emission that confirm the presence of electrons with energies up to 50[?]MeV; the data were collected during the Cassini fly-by of Jupiter. These energetic electrons may be repeatedly accelerated through an interaction with plasma waves, which can transfer energy into the electrons. Preliminary comparison of our data with model results suggests that electrons with energies of less than 20[?]MeV are more numerous than previously believed.

  4. Jupiter internal structure: the effect of different equations of state

    Science.gov (United States)

    Miguel, Y.; Guillot, T.; Fayon, L.

    2016-12-01

    Context. Heavy elements, even though they are a smaller constituent, are crucial to understand the formation history of Jupiter. Interior models are used to determine the amount of heavy elements in the interior of Jupiter, but this range is still subject to degeneracies because of the uncertainties in the equations of state. Aims: Before Juno mission data arrive, we present optimized calculations for Jupiter that explore the effect of different model parameters on the determination of the core and the mass of heavy elements of Jupiter. We compare recently published equations of state. Methods: The interior model of Jupiter was calculated from the equations of hydrostatic equilibrium, mass, and energy conservation, and energy transport. The mass of the core and heavy elements was adjusted to match the observed radius and gravitational moments of Jupiter. Results: We show that the determination of the interior structure of Jupiter is tied to the estimation of its gravitational moments and the accuracy of equations of state of hydrogen, helium, and heavy elements. Locating the region where helium rain occurs and defining its timescale is important to determine the distribution of heavy elements and helium in the interior of Jupiter. We show that the differences found when modeling the interior of Jupiter with recent EOS are more likely due to differences in the internal energy and entropy calculation. The consequent changes in the thermal profile lead to different estimates of the mass of the core and heavy elements, which explains differences in recently published interior models of Jupiter. Conclusions: Our results help clarify the reasons for the differences found in interior models of Jupiter and will help interpreting upcoming Juno data. Full appendix tables are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/596/A114

  5. Warm Jupiters Are Less Lonely than Hot Jupiters: Close Neighbors

    Science.gov (United States)

    Huang, Chelsea; Wu, Yanqin; Triaud, Amaury H. M. J.

    2016-07-01

    Exploiting the Kepler transit data, we uncover a dramatic distinction in the prevalence of sub-Jovian companions between systems that contain hot Jupiters (HJs) (periods inward of 10 days) and those that host warm Jupiters (WJs) (periods between 10 and 200 days). HJs, with the singular exception of WASP-47b, do not have any detectable inner or outer planetary companions (with periods inward of 50 days and sizes down to 2 R Earth). Restricting ourselves to inner companions, our limits reach down to 1 R Earth. In stark contrast, half of the WJs are closely flanked by small companions. Statistically, the companion fractions for hot and WJs are mutually exclusive, particularly in regard to inner companions. The high companion fraction of WJs also yields clues to their formation. The WJs that have close-by siblings should have low orbital eccentricities and low mutual inclinations. The orbital configurations of these systems are reminiscent of those of the low-mass close-in planetary systems abundantly discovered by the Kepler mission. This, and other arguments, lead us to propose that these WJs are formed in situ. There are indications that there may be a second population of WJs with different characteristics. In this picture, WASP-47b could be regarded as the extending tail of the in situ WJs into the HJ region and does not represent the generic formation route for HJs.

  6. The EJSM Jupiter Europa Orbiter: Planning Payload

    Science.gov (United States)

    Pappalardo, R. T.; Clark, K.; Greeley, R.; Hendrix, A. R.; Boldt, J.; Tan-Wang, G.; Lock, R.; van Houten, T.; Ludwinski, J.

    2008-09-01

    In the decade since the first return of Europa data by the Galileo spacecraft, the scientific understanding of Europa has greatly matured leading to the formulation of sophisticated new science objectives to be addressed through the acquisition of new data. The Jupiter Europa Orbiter (JEO) is one component of the proposed multi-spacecraft Europa Jupiter System Mission (EJSM) designed to obtain data in support of these new science objectives. The JEO planning payload, while notional, is used to quantify engineering aspects of the mission and spacecraft design, and operational scenarios required to obtain the data necessary to meet the science objectives. The instruments were defined to understand the viability of an approach to meet the measurement objectives, perform in the radiation environment and meet the planetary protection requirements. The actual instrument suite would ultimately be the result of an Announcement of Opportunity (AO) selection process carried out by NASA.

  7. Jupiter Laser Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Jupiter Laser Facility is an institutional user facility in the Physical and Life Sciences Directorate at LLNL. The facility is designed to provide a high degree...

  8. Inferno on Jupiter

    Institute of Scientific and Technical Information of China (English)

    诸葛勤

    1994-01-01

    The initial sketchy reports began filtering into the U. S. by E-maillate Saturday afternoon. First a Spanish observatory announced that it hadspotted a plume of gas billowing up from the edge of Jupiter. Then a

  9. Mercury's exosphere: observations during MESSENGER's First Mercury flyby.

    Science.gov (United States)

    McClintock, William E; Bradley, E Todd; Vervack, Ronald J; Killen, Rosemary M; Sprague, Ann L; Izenberg, Noam R; Solomon, Sean C

    2008-07-04

    During MESSENGER's first Mercury flyby, the Mercury Atmospheric and Surface Composition Spectrometer measured Mercury's exospheric emissions, including those from the antisunward sodium tail, calcium and sodium close to the planet, and hydrogen at high altitudes on the dayside. Spatial variations indicate that multiple source and loss processes generate and maintain the exosphere. Energetic processes connected to the solar wind and magnetospheric interaction with the planet likely played an important role in determining the distributions of exospheric species during the flyby.

  10. Orientation and Rotational Parameters of Asteroid 4179 Toutatis: New Insights from Chang'e-2's Close Flyby

    CERN Document Server

    Zhao, Yuhui; Huang, Jiangchuan; Hu, Shoucun; Hou, Xiyun; Li, Yuan; Ip, Wing-Huen

    2015-01-01

    In this work, we investigate the rotational dynamics of the ginger-shaped near-Earth asteroid 4179 Toutatis, which was closely observed by Chang'e-2 at a distance of $770\\pm120~$ meters from the asteroid's surface during the outbound flyby \\citep{Huang2013} on 13 December 2012. A sequence of high-resolution images was acquired during the flyby mission. In combination with ground-based radar observations collected over the last two decades, we analyze these flyby images and determine the orientation of the asteroid at the flyby epoch. The 3-1-3 Euler angles of the conversion matrix from the J2000 ecliptic coordinate system to the body-fixed frame are evaluated to be $-20.1^\\circ\\pm1^\\circ$, $27.6^\\circ\\pm1^\\circ$ and $42.2^\\circ\\pm1^\\circ$, respectively. The least-squares method is utilized to determine the rotational parameters and spin state of Toutatis. The characteristics of the spin-state parameters and angular momentum variations are extensively studied using numerical simulations, which confirm those re...

  11. Argus: A New Frontiers mission to observe Io

    Science.gov (United States)

    Chen, Erinna; Borer, N. K.; Choi, D. S.; Craft, K. L.; Fortenberry, R.; Harben, J. P.; Isaacson, P.; Johnson, A.; Mabry, J.; McDunn, T.; Millham, R. A.; Pankine, A.; Prater, A.; Rodriguez, H. M.; Smith, D. J.; Snowden, D.

    2008-09-01

    Jupiter's moon Io is the most volcanically active body in the Solar System. By investigating its active volcanism, we may address fundamental questions concerning habitability of bodies like Europa and Enceladus that exhibit significant amounts of tidal heating. Investigating Io's volcanism also has implications for constraining processes on the early Earth and other terrestrial bodies that may have had a magma ocean. We present a study of a New Frontiers class mission to Io called Argus. The Argus mission would employ a high-inclination Jovicentric orbit and, over a two-year period, the spacecraft would encounter Io 40 times at 100 km altitude closest approach. Lower-altitude flybys may be possible toward the end of the mission duration. The spacecraft would employ ASRGs for power and utilize radiation-hardened technology developed for a presumed outer planets flagship mission. The payload on Argus would consist of five instruments: a narrow angle camera, a thermal imager, a near-IR imaging spectrometer, a UV spectrometer and an ion and neutral mass spectrometer. The expected science data to be returned would include: a global map of Io at 1 km resolution, with local and stereo imaging down to 10 m resolution, a global map of surface mineralogical composition at 3 km resolution with targeted observations down to 300 m resolution, a global heat flow map with resolution down to 10 km, UV images of multiple volcanic plumes and in-situ measurements of plume and atmospheric compositions. This mission concept study was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration during NASA's 20th Annual Planetary Science Summer School.

  12. Attitude Determination and Control Subsystem (ADCS) Preparations for the EPOXI Flyby of Comet Haley 2

    Science.gov (United States)

    Luna, Michael E.; Collins, Stephen M.

    2011-01-01

    On November 4, 2010 the already "in-flight" Deep Impact spacecraft flew within 700km of comet 103P/Hartley 2 as part of its extended mission EPOXI, the 5th time to date any spacecraft visited a comet. In 2005, the spacecraft had previously imaged a probe impact comet Tempel 1. The EPOXI flyby marked the first time in history that two comets were explored with the same instruments on a re-used spacecraft-with hardware and software originally designed and optimized for a different mission. This made the function of the attitude determination and control subsystem (ADCS) critical to the successful execution of the EPOXI flyby. As part of the spacecraft team preparations, the ADCS team had to perform thorough sequence reviews, key spacecraft activities and onboard calibrations. These activities included: review of background sequences for the initial conditions vector, sun sensor coefficients, and reaction wheel assembly (RWA) de-saturations; design and execution of 10 trajectory correction maneuvers; science calibration of the two telescope instruments; a flight demonstration of the fastest turns conducted by the spacecraft between Earth and comet point; and assessment of RWA health (given RWA problems on other spacecraft).

  13. Attitude Determination and Control Subsystem (ADCS) Preparations for the EPOXI Flyby of Comet Haley 2

    Science.gov (United States)

    Luna, Michael E.; Collins, Stephen M.

    2011-01-01

    On November 4, 2010 the already "in-flight" Deep Impact spacecraft flew within 700km of comet 103P/Hartley 2 as part of its extended mission EPOXI, the 5th time to date any spacecraft visited a comet. In 2005, the spacecraft had previously imaged a probe impact comet Tempel 1. The EPOXI flyby marked the first time in history that two comets were explored with the same instruments on a re-used spacecraft-with hardware and software originally designed and optimized for a different mission. This made the function of the attitude determination and control subsystem (ADCS) critical to the successful execution of the EPOXI flyby. As part of the spacecraft team preparations, the ADCS team had to perform thorough sequence reviews, key spacecraft activities and onboard calibrations. These activities included: review of background sequences for the initial conditions vector, sun sensor coefficients, and reaction wheel assembly (RWA) de-saturations; design and execution of 10 trajectory correction maneuvers; science calibration of the two telescope instruments; a flight demonstration of the fastest turns conducted by the spacecraft between Earth and comet point; and assessment of RWA health (given RWA problems on other spacecraft).

  14. AMTEC radioisotope power system design and analysis for Pluto Express Fly-By

    Energy Technology Data Exchange (ETDEWEB)

    Hendricks, T.J.; Huang, C.; Sievers, R.K. [Advanced Modular Power Systems, Inc., Ann Arbor, MI (United States)

    1997-12-31

    The Pluto Express Fly-By program requires a Radioisotope Power System (RPS) to supply spacecraft power for various internal functions and mission instruments and experiments. AMTEC (Alkali-Metal Thermal-Electric Conversion) power conversion is the DOE-selected technology for an advanced, high-efficiency RPS to power the Pluto Express Fly-By spacecraft. An AMTEC-based RPS using the General Purpose Heat Source (GPHS) has been conceptually designed to satisfy the Pluto Express power requirements. Integrated AMTEC cell and system thermal/electrical design analyses, structural design analyses, and mass analyses were performed to define an optimum system design. Using fresh radioisotope fuel at beginning of mission, the RPS produces 102 watts of power, has a mass of 8.35 kg (specific power density = 12.2 watts/kg), with a system conversion efficiency of 20.3%. Mass/power scale-up estimates have also been generated, indicating that a 150-watt version of this RPS would weigh approximately 11.3 kg. This paper presents and discusses the key features of this RPS design, the design and analysis methodology, and the numerous system and AMTEC cell tradeoff studies establishing the optimum AMTEC-based RPS.

  15. Jupiter's Dynamic Magnetosphere

    Science.gov (United States)

    Vogt, M. F.; Bunce, E. J.; Kronberg, E. A.; Jackman, C. M.

    2014-12-01

    Jupiter's magnetosphere is a highly dynamic environment. Hundreds of reconnection events have been identified in Jupiter's magnetotail through analysis of magnetic field and particle measurements collected by the Galileo spacecraft. Quasi-periodic behavior, suggestive of reconnection, has been intermittently observed on a ~2-3 day time scale in several data sets, including magnetic field dipolarizations, flow bursts, auroral polar dawn spots, and the hectometric radio emission. In this paper we review the present state of knowledge of Jovian magnetospheric dynamics. Throughout the discussion, we highlight similarities and differences to Saturn's magnetosphere. For example, recent analysis of plasmoid signatures at both Jupiter and Saturn has established the role of tail reconnection in the overall mass and flux transport in the outer planet magnetospheres. The results for both Jupiter and Saturn suggest that the observed mass loss rate due to tail reconnection and plasmoid release is insufficient to account for the mass input rate from the moons Io and Enceladus, respectively. We also present new analysis in which we use the Michigan mSWiM propagated solar wind MHD model to estimate the solar wind conditions upstream of Jupiter. This information allows us to determine whether reconnection events occur preferentially during certain solar wind conditions, or whether there is evidence that the solar wind modulates the quasi-periodicity seen in the field dipolarizations and flow bursts.

  16. JANUS: the visible camera onboard the ESA JUICE mission to the Jovian system

    Science.gov (United States)

    Palumbo, Pasquale; Jaumann, Ralf; Cremonese, Gabriele; Hoffmann, Harald; Debei, Stefano; Della Corte, Vincenzo; Holland, Andrew; Lara, Luisa Maria

    2014-05-01

    The JUICE (JUpiter ICy moons Explorer) mission [1] was selected in May 2012 as the first Large mission in the frame of the ESA Cosmic Vision 2015-2025 program. JUICE is now in phase A-B1 and its final adoption is planned by late 2014. The mission is aimed at an in-depth characterization of the Jovian system, with an operational phase of about 3.5 years. Main targets for this mission will be Jupiter, its satellites and rings and the complex relations within the system. Main focus will be on the detailed investigation of three of Jupiter's Galilean satellites (Ganymede, Europa, and Callisto), thanks to several fly-bys and 9 months in orbit around Ganymede. JANUS (Jovis, Amorum ac Natorum Undique Scrutator) is the camera system selected by ESA to fulfill the optical imaging scientific requirements of JUICE. It is being developed by a consortium involving institutes in Italy, Germany, Spain and UK, supported by respective Space Agencies, with the support of Co-Investigators also from USA, France, Japan and Israel. The Galilean satellites Io, Europa, Ganymede and Callisto show an increase in geologic activity with decreasing distance to Jupiter [e.g., 2]. The three icy Galilean satellites Callisto, Ganymede and Europa show a tremendous diversity of surface features and differ significantly in their specific evolutionary paths. Each of these moons exhibits its own fascinating geologic history - formed by competition and also combination of external and internal processes. Their origins and evolutions are influenced by factors such as density, temperature, composition (volatile compounds), stage of differentiation, volcanism, tectonism, the rheological reaction of ice and salts to stress, tidal effects, and interactions with the Jovian magnetosphere and space. These interactions are still recorded in the present surface geology. The record of geological processes spans from possible cryovolcanism through widespread tectonism to surface degradation and impact cratering

  17. Jupiter - friend or foe?

    Science.gov (United States)

    Horner, J.; Jones, B. W.

    2007-08-01

    Throughout both popular science and academia, there is a pervasive belief that Jupiter has acted as a celestial shield, reducing the impact rate on the Earth, and making the planet a significantly more conducive site for the evolution and survival of life. This old idea has, however, undergone little detailed scrutiny. In the first of a series of studies aimed at a better understanding of this idea, we examine the variation in the impact rate on the Earth which results from bodies moving inwards from the Edgeworth- Kuiper belt as a function of the mass of a giant planet in Jupiter's orbit. The results are not entirely what would be expected under the "Jupiter Shield" paradigm.

  18. Sharpening Up Jupiter

    Science.gov (United States)

    2008-10-01

    New image-correction technique delivers sharpest whole-planet ground-based picture ever A record two-hour observation of Jupiter using a superior technique to remove atmospheric blur has produced the sharpest whole-planet picture ever taken from the ground. The series of 265 snapshots obtained with the Multi-Conjugate Adaptive Optics Demonstrator (MAD) prototype instrument mounted on ESO's Very Large Telescope (VLT) reveal changes in Jupiter's smog-like haze, probably in response to a planet-wide upheaval more than a year ago. Sharpening Up Jupiter ESO PR Photo 33/08 Sharpening Up Jupiter Being able to correct wide field images for atmospheric distortions has been the dream of scientists and engineers for decades. The new images of Jupiter prove the value of the advanced technology used by MAD, which uses two or more guide stars instead of one as references to remove the blur caused by atmospheric turbulence over a field of view thirty times larger than existing techniques [1]. "This type of adaptive optics has a big advantage for looking at large objects, such as planets, star clusters or nebulae," says lead researcher Franck Marchis, from UC Berkeley and the SETI Institute in Mountain View, California, USA. "While regular adaptive optics provides excellent correction in a small field of view, MAD provides good correction over a larger area of sky. And in fact, were it not for MAD, we would not have been able to perform these amazing observations." MAD allowed the researchers to observe Jupiter for almost two hours on 16 and 17 August 2008, a record duration, according to the observing team. Conventional adaptive optics systems using a single Jupiter moon as reference cannot monitor Jupiter for so long because the moon moves too far from the planet. The Hubble Space Telescope cannot observe Jupiter continuously for more than about 50 minutes, because its view is regularly blocked by the Earth during Hubble's 96-minute orbit. Using MAD, ESO astronomer Paola Amico

  19. Jupiter's Rings: Sharpest View

    Science.gov (United States)

    2007-01-01

    The New Horizons spacecraft took the best images of Jupiter's charcoal-black rings as it approached and then looked back at Jupiter. The top image was taken on approach, showing three well-defined lanes of gravel- to boulder-sized material composing the bulk of the rings, as well as lesser amounts of material between the rings. New Horizons snapped the lower image after it had passed Jupiter on February 28, 2007, and looked back in a direction toward the sun. The image is sharply focused, though it appears fuzzy due to the cloud of dust-sized particles enveloping the rings. The dust is brightly illuminated in the same way the dust on a dirty windshield lights up when you drive toward a 'low' sun. The narrow rings are confined in their orbits by small 'shepherding' moons.

  20. A Preliminary Jupiter Model

    CERN Document Server

    Hubbard, W B

    2016-01-01

    In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen-helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses, and a hydrogen-helium-rich envelope with...

  1. A Preliminary Jupiter Model

    Science.gov (United States)

    Hubbard, W. B.; Militzer, B.

    2016-03-01

    In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen-helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses and a hydrogen-helium-rich envelope with approximately three times solar metallicity.

  2. Status of the Ganymede Laser Altimeter (GALA) for ESA's Jupiter Icy Moons Explorer (JUICE)

    Science.gov (United States)

    Hussmann, Hauke; Luedicke, Fabian

    2017-04-01

    The Ganymede Laser Altimeter (GALA) is one of the instruments selected for ESA's Jupiter Icy Moons Explorer (JUICE). A fundamental goal of any exploratory space mission is to characterize and measure the shape, topography, and rotation of the target bodies. A state of the art tool for this task is laser altimetry because it can provide absolute topographic height and position with respect to a body centered reference system. With respect to Ganymede, the GALA instrument aims at mapping of global, regional and local topography; confirming the global subsurface ocean and further characterization of the water-ice/liquid shell by monitoring the dynamic response of the ice shell to tidal forces; providing constraints on the forced physical librations and spin-axis obliquity; determining Ganymede's shape; obtaining detailed topographic profiles across the linear features of grooved terrain, impact structures, possible cryo-volcanic features and other different surface units; providing information about slope, roughness and albedo (at 1064nm) of Ganymede's surface. After several flyby's (Ganymede, Europa, Callisto) it is scheduled that the JUICE orbiter will enter first into an elliptical orbit (200 km x 10.000 km) for around 150 days and then into a circular orbit (500 km) around Ganymede for 130 days. Accordingly to the different orbits and trajectories, distances to the moons respectively, the spot size of the GALA laser varies between 21 m and 140 m. GALA uses the direct-detection (classical) approach of laser altimetry. Laser pulses are emitted at a wavelength of 1064 nm by using an actively Q-switched Nd:Yag laser. The pulse energy and pulse repetition frequency are 17 mJ at 30 Hz (nominal), respectively. For targeted observations and flybys the frequency can be switched to 50 Hz. The emission time of each pulse is measured by the detector. The beam is reflected from the surface and received at a 25 cm diameter telescope. The returning laser pulse is refocused onto

  3. A dimensionless relative trajectory estimation algorithm for autonomous imaging of a small astronomical body in a close distance flyby

    Science.gov (United States)

    Ariu, Kaito; Inamori, Takaya; Funase, Ryu; Nakasuka, Shinichi

    2016-08-01

    The world's first micro-spacecraft, "Proximate Object Close flYby with Optical Navigation" (PROCYON) has the advanced mission to approach an asteroid in dozen km (a one-order closer imaging distance compared with previous probes). In such a close distance encounter, the estimation of the relative trajectory of the target is necessary to perform autonomous imaging. However, the estimation is difficult owing to rapid changes of the line-of-sight direction of the target body. To overcome this problem, a novel dimensionless or direction only relative trajectory estimation algorithm, which uses a least square method, is proposed. The evaluation function for the least square method coincides with the error property of picture information to enable all of its calculations to be recursive and linear. It is suited for the implementation on the limited on-board computer. Numerical simulation results indicate that the proposed algorithm should enable the one-order closer flyby observation.

  4. Transiting exoplanets from the CoRoT space mission IX. CoRoT-6b: a transiting `hot Jupiter' planet in an 8.9d orbit around a low-metallicity star

    CERN Document Server

    Fridlund, M; Alonso, R; Deleuil, M; Gandolfi, D; Gillon, M; Bruntt, H; Alapini, A; Csizmadia, Sz; Guillot, T; Lammer, H; Aigrain, S; Almenara, J M; Auvergne, M; Baglin, A; Barge, P; Borde, P; Bouchy, F; Cabrera, J; Carone, L; Carpano, S; Deeg, H J; De la Reza, R; Dvorak, R; Erikson, A; Ferraz-Mello, S; Guenther, E; Gondoin, P; Hartog, R den; Hatzes, A; Jorda, L; Leger, A; Llebaria, A; Magain, P; Mazeh, T; Moutou, C; Ollivier, M; Patzold, M; Queloz, D; Rauer, H; Rouan, D; Samuel, B; Schneider, J; Shporer, A; Stecklum, B; Tingley, B; Weingrill, J; Wuchterl, G

    2010-01-01

    The CoRoT satellite exoplanetary team announces its sixth transiting planet in this paper. We describe and discuss the satellite observations as well as the complementary ground-based observations - photometric and spectroscopic - carried out to assess the planetary nature of the object and determine its specific physical parameters. The discovery reported here is a `hot Jupiter' planet in an 8.9d orbit, 18 stellar radii, or 0.08 AU, away from its primary star, which is a solar-type star (F9V) with an estimated age of 3.0 Gyr. The planet mass is close to 3 times that of Jupiter. The star has a metallicity of 0.2 dex lower than the Sun, and a relatively high $^7$Li abundance. While thelightcurveindicatesamuchhigherlevelof activity than, e.g., the Sun, there is no sign of activity spectroscopically in e.g., the [Ca ] H&K lines.

  5. Transiting exoplanets from the CoRoT space mission. XIII. CoRoT-13b: a dense hot Jupiter in transit around a star with solar metallicity and super-solar lithium content

    CERN Document Server

    Cabrera, J; Ollivier, M; Diaz, R F; Csizmadia, Sz; Aigrain, S; Alonso, R; Almenara, J -M; Auvergne, M; Baglin, A; Barge, P; Bonomo, A S; Borde, P; Bouchy, F; Carone, L; Carpano, S; Deleuil, M; Deeg, H J; Dvorak, R; Erikson, A; Ferraz-Mello, S; Fridlund, M; Gandolfi, D; Gazzano, J -C; Gillon, M; Guenther, E W; Guillot, T; Hatzes, A; Havel, M; Hebrard, G; Jorda, L; Leger, A; Llebaria, A; Lammer, H; Lovis, C; Mazeh, T; Moutou, C; Ofir, A; von Paris, P; Patzold, M; Queloz, D; Rauer, H; Rouan, D; Santerne, A; Schneider, J; Tingley, B; Titz-Weider, R; Wuchterl, G

    2010-01-01

    We announce the discovery of the transiting planet CoRoT-13b. Ground based follow-up in CFHT and IAC80 confirmed CoRoT's observations. The mass of the planet was measured with the HARPS spectrograph and the properties of the host star were obtained analyzing HIRES spectra from the Keck telescope. It is a hot Jupiter-like planet with an orbital period of 4.04 days, 1.3 Jupiter masses, 0.9 Jupiter radii, and a density of 2.34 g cm-3. It orbits a G0V star with Teff=5945K, M*=1.09 Msun, R*=1.01 Rsun, solar metallicity, a lithium content of +1.45 dex, and an estimated age between 0.12 and 3.15 Gyr. The lithium abundance of the star is consistent with its effective temperature, activity level, and age range derived from the stellar analysis. The density of the planet is extreme for its mass. It implies the existence of an amount of heavy elements with a mass between about 140 and 300 Mearth.

  6. Jupiter's Big Bang.

    Science.gov (United States)

    McDonald, Kim A.

    1994-01-01

    Collision of a comet with Jupiter beginning July 16, 1994 will be observed by astronomers worldwide, with computerized information relayed to a center at the University of Maryland, financed by the National Aeronautics and Space Administration and National Science Foundation. Geologists and paleontologists also hope to learn more about earth's…

  7. Radiation belts of jupiter.

    Science.gov (United States)

    Stansberry, K G; White, R S

    1973-12-07

    Predictions of Jupiter's electron and proton radiation belts are based mainly on decimeter observations of 1966 and 1968. Extensive calculations modeling radial diffusion of particles inward from the solar wind and electron synchrotron radiation are used to relate the predictions and observations.

  8. A Transiting Jupiter Analog

    CERN Document Server

    Kipping, David M; Henze, Chris; Teachey, Alex; Isaacson, Howard T; Petigura, Erik A; Marcy, Geoffrey W; Buchhave, Lars A; Chen, Jingjing; Bryson, Steve T; Sandford, Emily

    2016-01-01

    Decadal-long radial velocity surveys have recently started to discover analogs to the most influential planet of our solar system, Jupiter. Detecting and characterizing these worlds is expected to shape our understanding of our uniqueness in the cosmos. Despite the great successes of recent transit surveys, Jupiter analogs represent a terra incognita, owing to the strong intrinsic bias of this method against long orbital periods. We here report on the first validated transiting Jupiter analog, Kepler-167e (KOI-490.02), discovered using Kepler archival photometry orbiting the K4-dwarf KIC-3239945. With a radius of $(0.91\\pm0.02)$ $R_{\\mathrm{Jup}}$, a low orbital eccentricity ($0.06_{-0.04}^{+0.10}$) and an equilibrium temperature of $(131\\pm3)$ K, Kepler-167e bears many of the basic hallmarks of Jupiter. Kepler-167e is accompanied by three Super-Earths on compact orbits, which we also validate, leaving a large cavity of transiting worlds around the habitable-zone. With two transits and continuous photometric ...

  9. Benefits to the Europa Clipper Mission Provided by the Space Launch System

    Science.gov (United States)

    Creech, Stephen D.; Patel, Keyur

    2013-01-01

    The National Aeronautics and Space Administration's (NASA's) proposed Europa Clipper mission would provide an unprecedented look at the icy Jovian moon, and investigate its environment to determine the possibility that it hosts life. Focused on exploring the water, chemistry, and energy conditions on the moon, the spacecraft would examine Europa's ocean, ice shell, composition and geology by performing 32 low-altitude flybys of Europa from Jupiter orbit over 2.3 years, allowing detailed investigations of globally distributed regions of Europa. In hopes of expediting the scientific program, mission planners at NASA's Jet Propulsion Laboratory are working with the Space Launch System (SLS) program, managed at Marshall Space Flight Center. Designed to be the most powerful launch vehicle ever flown, SLS is making progress toward delivering a new capability for exploration beyond Earth orbit. The SLS rocket will offer an initial low-Earth-orbit lift capability of 70 metric tons (t) beginning with a first launch in 2017 and will then evolve into a 130 t Block 2 version. While the primary focus of the development of the initial version of SLS is on enabling human exploration missions beyond low Earth orbit using the Orion Multi-Purpose Crew Vehicle, the rocket offers unique benefits to robotic planetary exploration missions, thanks to the high characteristic energy it provides. This paper will provide an overview of both the proposed Europa Clipper mission and the Space Launch System vehicle, and explore options provided to the Europa Clipper mission for a launch within a decade by a 70 t version of SLS with a commercially available 5-meter payload fairing, through comparison with a baseline of current Evolved Expendable Launch Vehicle (EELV) capabilities. Compared to that baseline, a mission to the Jovian system could reduce transit times to less than half, or increase mass to more than double, among other benefits. In addition to these primary benefits, the paper will

  10. New Horizons Successful Completes the Historic First Flyby of Pluto and Its Moons

    Science.gov (United States)

    Ennico, Kimberly

    2015-01-01

    On July 14, 2015, after a 9.5 year trek across the solar system, NASA's New Horizons spacecraft flew by the dwarf planet Pluto and its system of moons, taking imagery, spectra and in-situ particle data. Data from New Horizons will address numerous outstanding questions on the geology and composition of Pluto and Charon, plus measurements of Pluto's atmosphere, and provide revised understanding of the formation and evolution of Pluto and Charon and its smaller moons. This data set is an invaluable glimpse into the outer Third Zone of the solar system. Data from the intense July 14th fly-by sequence will be downlinked to Earth over a period of 16 months, the duration set by the large data set (over 60 GBits) and the limited transmitted bandwidth rates (approx. 1-2 kbps) and sharing the three 70 m DSN assets with our missions. The small fraction (approx. 1%) of data downlinked during the early phase of the flyby has already revealed Pluto and Charon to be very different worlds, with increasing and dynamic complexity.

  11. Physical properties of ESA/NASA Rosetta target asteroid (21) Lutetia: Shape and flyby geometry

    CERN Document Server

    Carry, B; Leyrat, C; Merline, W J; Drummond, J D; Conrad, A; Weaver, H A; Tamblyn, P M; Chapman, C R; Dumas, C; Colas, F; Christou, J C; Dotto, E; Perna, D; Fornasier, S; Bernasconi, L; Behrend, R; Vachier, F; Kryszczynska, A; Polinska, M; Fulchignoni, M; Roy, R; Naves, R; Poncy, R; Wiggins, P

    2010-01-01

    Aims. We determine the physical properties (spin state and shape) of asteroid (21) Lutetia, target of the ESA/NASA Rosetta mission, to help in preparing for observations during the flyby on 2010 July 10 by predicting the orientation of Lutetia as seen from Rosetta. Methods. We use our novel KOALA inversion algorithm to determine the physical properties of asteroids from a combination of optical lightcurves, disk-resolved images, and stellar occultations, although the latter are not available for (21) Lutetia. Results. We find the spin axis of (21) Lutetia to lie within 5 degrees of ({\\lambda} = 52 deg., {\\beta} = -6 deg.) in Ecliptic J2000 reference frame (equatorial {\\alpha} = 52 deg., {\\delta} = +12 deg.), and determine an improved sidereal period of 8.168 270 \\pm 0.000 001 h. This pole solution implies the southern hemisphere of Lutetia will be in "seasonal" shadow at the time of the flyby. The apparent cross-section of Lutetia is triangular as seen "pole-on" and more rectangular as seen "equator-on". The ...

  12. The high albedo of the hot Jupiter Kepler-7b

    DEFF Research Database (Denmark)

    Demory, B.-O.; Seager, S.; Madhusudhan, N.

    2011-01-01

    . The NASA Kepler mission provides a means to widen the sample and to assess the extent to which hot Jupiter albedos are low. We present a global analysis of Kepler-7 b based on Q0-Q4 data, published radial velocities, and asteroseismology constraints. We measure an occultation depth in the Kepler bandpass...

  13. Natural radio emission of Jupiter as interferences for radar investigations of the icy satellites of Jupiter

    Science.gov (United States)

    Cecconi, B.; Hess, S.; Hérique, A.; Santovito, M. R.; Santos-Costa, D.; Zarka, P.; Alberti, G.; Blankenship, D.; Bougeret, J.-L.; Bruzzone, L.; Kofman, W.

    2012-02-01

    Radar instruments are part of the core payload of the two Europa Jupiter System Mission (EJSM) spacecraft: NASA-led Jupiter Europa Orbiter (JEO) and ESA-led Jupiter Ganymede Orbiter (JGO). At this point of the project, several frequency bands are under study for radar, which ranges between 5 and 50 MHz. Part of this frequency range overlaps with that of the natural jovian radio emissions, which are very intense in the decametric range, below 40 MHz. Radio observations above 40 MHz are free of interferences, whereas below this threshold, careful observation strategies have to be investigated. We present a review of spectral intensity, variability and sources of these radio emissions. As the radio emissions are strongly beamed, it is possible to model the visibility of the radio emissions, as seen from the vicinity of Europa or Ganymede. We have investigated Io-related radio emissions as well as radio emissions related to the auroral oval. We also review the radiation belts synchrotron emission characteristics. We present radio sources visibility products (dynamic spectra and radio source location maps, on still frames or movies), which can be used for operation planning. This study clearly shows that a deep understanding of the natural radio emissions at Jupiter is necessary to prepare the future EJSM radar instrumentation. We show that this radio noise has to be taken into account very early in the observation planning and strategies for both JGO and JEO. We also point out possible synergies with RPW (Radio and Plasma Waves) instrumentations.

  14. Polarized Light from Jupiter

    Science.gov (United States)

    2001-01-01

    These images taken through the wide angle camera near closest approach in the deep near-infrared methane band, combined with filters which sense electromagnetic radiation of orthogonal polarization, show that the light from the poles is polarized. That is, the poles appear bright in one image, and dark in the other. Polarized light is most readily scattered by aerosols. These images indicate that the aerosol particles at Jupiter's poles are small and likely consist of aggregates of even smaller particles, whereas the particles at the equator and covering the Great Red Spot are larger. Images like these will allow scientists to ascertain the distribution, size and shape of aerosols, and consequently, the distribution of heat, in Jupiter's atmosphere.

  15. Jupiter's Water Worlds

    Science.gov (United States)

    Pappalardo, R. T.

    2004-01-01

    When the twin Voyager spacecraft cruised past Jupiter in 1979, they did more than rewrite the textbooks on the giant planet. Their cameras also unveiled the astounding diversity of the four planet-size moons of ice and stone known as the Galilean satellites. The Voyagers revealed the cratered countenance of Callisto, the valleys and ridges of Ganymede, the cracked face of Europa, and the spewing volcanoes of Io. But it would take a spacecraft named for Italian scientist Galileo, who discovered the moons in 1610, to reveal the true complexity of these worlds and to begin to divulge their interior secrets. Incredibly, the Galileo data strongly suggest that Jupiter's three large icy moons (all but rocky Io) hide interior oceans.

  16. A PRELIMINARY JUPITER MODEL

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, W. B. [Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ 85721 (United States); Militzer, B. [Department of Earth and Planetary Science, Department of Astronomy, University of California, Berkeley, CA 94720 (United States)

    2016-03-20

    In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen–helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses and a hydrogen–helium-rich envelope with approximately three times solar metallicity.

  17. Jupiter's Grand Attack

    Science.gov (United States)

    Batygin, Konstantin

    2017-06-01

    The statistics of extrasolar planetary systems indicate that the default mode of planetary formation generates planets with orbital periods shorter than 100 days, and masses substantially exceeding that of the Earth. When viewed in this context, the Solar System, which contains no planets interior to Mercury's 88-day orbit, is unusual. Extra-solar planetary detection surveys also suggest that planets with masses and periods broadly similar to Jupiter's are somewhat uncommon, with occurrence fraction of less than ~ 10%. In this talk, I will present calculations which show that a popular formation scenario for Jupiter and Saturn, in which Jupiter migrates inward from a > 5AU to a ˜ 1.5 AU and then reverses direction, can explain the low overall mass of the Solar System's terrestrial planets, as well as the absence of planets with a 10 - 100 km planetesimals into low- order mean-motion resonances, shepherding of order 10 Earth masses of this material into the a ˜ 1 AU region while exciting substantial orbital eccentricity (e ˜ 0.2 - 0.4). We argue that under these conditions, a collisional cascade will ensue, generating a planetesimal disk that would have flushed any preexisting short-period super-Earth-like planets into the Sun. In this scenario, the Solar System's terrestrial planets formed from gas-starved mass-depleted debris that remained after the primary period of dynamical evolution.

  18. Voyager picture of Jupiter

    Science.gov (United States)

    1998-01-01

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

  19. Jupiter Europa Orbiter Architecture Definition Process

    Science.gov (United States)

    Rasmussen, Robert; Shishko, Robert

    2011-01-01

    The proposed Jupiter Europa Orbiter mission, planned for launch in 2020, is using a new architectural process and framework tool to drive its model-based systems engineering effort. The process focuses on getting the architecture right before writing requirements and developing a point design. A new architecture framework tool provides for the structured entry and retrieval of architecture artifacts based on an emerging architecture meta-model. This paper describes the relationships among these artifacts and how they are used in the systems engineering effort. Some early lessons learned are discussed.

  20. Solar wind influence on Jupiter's aurora

    Science.gov (United States)

    Gyalay, Szilard; Vogt, Marissa F.; Withers, Paul; Bunce, Emma J.

    2016-10-01

    Jupiter's main auroral emission is driven by a system of corotation enforcement currents that arises to speed up outflowing Iogenic plasma and is not due to the magnetosphere-solar wind interaction like at Earth. The solar wind is generally expected to have only a small influence on Jupiter's magnetosphere and aurora compared to the influence of rotational stresses due to the planet's rapid rotation. However, there is considerable observational evidence that the solar wind does affect the magnetopause standoff distance, auroral radio emissions, and the position and brightness of the UV auroral emissions. Using the Michigan Solar Wind Model (mSWiM) to predict the solar wind conditions upstream of Jupiter we have identified intervals of high and low solar wind dynamic pressure in the Galileo dataset, and use this information to quantify how a magnetospheric compression affects the magnetospheric field configuration. We have developed separate spatial fits to the compressed and nominal magnetic field data, accounting for variations with radial distance and local time. These two fits can be used to update the flux equivalence mapping model of Vogt et al. (2011), which links auroral features to source regions in the middle and outer magnetosphere. The updated version accounts for changing solar wind conditions and provides a way to quantify the expected solar wind-induced variability in the ionospheric mapping of the main auroral emission, satellite footprints, and other auroral features. Our results are highly relevant to interpretation of the new auroral observations from the Juno mission.

  1. Himalia, a Small Moon of Jupiter

    Science.gov (United States)

    2001-01-01

    NASA's Cassini spacecraft captured images of Himalia, the brightest of Jupiter's outer moons, on Dec. 19, 2000, from a distance of 4.4 million kilometers (2.7 million miles).This near-infrared image, with a resolution of about 27 kilometers (17 miles) per pixel, indicates that the side of Himalia facing the spacecraft is roughly 160 kilometers (100 miles) in the up-down direction. Himalia probably has a non-spherical shape. Scientists believe it is a body captured into orbit around Jupiter, most likely an irregularly shaped asteroid.In the main frame, an arrow indicates Himalia. North is up. The inset shows the little moon magnified by a factor of 10, plus a graphic indicating Himalia's size and the direction of lighting (with sunlight coming from the left). Cassini's pictures of Himalia were taken during a brief period when Cassini's attitude was stabilized by thrusters instead of by a steadier reaction-wheel system. No spacecraft or telescope had previously shown any of Jupiter's outer moons as more than a star-like single dot.Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.

  2. Selection and trajectory design to mission secondary targets

    Science.gov (United States)

    Victorino Sarli, Bruno; Kawakatsu, Yasuhiro

    2017-02-01

    Recently, with new trajectory design techniques and use of low-thrust propulsion systems, missions have become more efficient and cheaper with respect to propellant. As a way to increase the mission's value and scientific return, secondary targets close to the main trajectory are often added with a small change in the transfer trajectory. As a result of their large number, importance and facility to perform a flyby, asteroids are commonly used as such targets. This work uses the Primer Vector theory to define the direction and magnitude of the thrust for a minimum fuel consumption problem. The design of a low-thrust trajectory with a midcourse asteroid flyby is not only challenging for the low-thrust problem solution, but also with respect to the selection of a target and its flyby point. Currently more than 700,000 minor bodies have been identified, which generates a very large number of possible flyby points. This work uses a combination of reachability, reference orbit, and linear theory to select appropriate candidates, drastically reducing the simulation time, to be later included in the main trajectory and optimized. Two test cases are presented using the aforementioned selection process and optimization to add and design a secondary flyby to a mission with the primary objective of 3200 Phaethon flyby and 25143 Itokawa rendezvous.

  3. Voyager 2 Jupiter Eruption Movie

    Science.gov (United States)

    2000-01-01

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

  4. The impact of dust grains on fast fly-by spacecraft: Momentum multiplication, measurements and theory

    Science.gov (United States)

    McDonnell, J. A. M.; Stevenson, T. J.; Evans, S. T.; Alexander, M.; Lyons, D.; Tanner, W.; Anz, P.; Hyde, T.; Chen, A.-L.

    Energy partitioning during the very high impact speed encountered in a cometary fly-by mission causes a target mass expulsion which leads to a momentum impulse on the target exceeding that of the incident momentum. Theoretical and computational studies are required to provide a basis for predictions of the response at Halley encounter, since experimental data from acceleration of microspheres extends currently only to some 10 kms-1. Such data obtained from the 2 MV Canterbury microparticle accelerator is presented: this demonstrates a target momentum enhancement E which can be approximated by a form E = 1+(V/Vo)β. Over the range 1 to 8 kms-1 the relationship is satisfied by Vo = 2 kms-1 and β = 2. Theoretical considerations of energy partitioning lead to constraints on the extrapolation of this functional dependence to very high velocities and the transition to β ballistic pendulum data, but the ES data indicates a figure considerably higher.

  5. A Day on Jupiter (Animation)

    Science.gov (United States)

    2007-01-01

    This 'movie' strings 11 images of Jupiter captured by the New Horizons Long Range Reconnaissance Imager (LORRI) on January 9, 2007, when the spacecraft was about 80 million kilometers (49.6 million miles) from the giant planet. The sequence covers a full 10-hour rotation of Jupiter, during which the moons Ganymede and Io -- as well as the shadows they cast on Jupiter -- move across the camera's field of view.

  6. Voyage to Troy: A mission concept for the exploration of the Trojan asteroids

    Science.gov (United States)

    Saikia, S.; Das, A.; Laipert, F.; Dapkus, C.; Kendall, J.; Bowling, T.; Steckloff, J.; Holbert, S.; Graves, K.; Anthony, T.; Bobick, R.; Huang, Y.; Stuart, J.; Longuski, J.; Minton, D.

    2014-07-01

    The Trojan asteroids, located at Jupiter's L4 and L5 Lagrange points, are a potential source of insights into long-standing questions on the origin and early history of the Solar System. The 2013 Planetary Science Decadal Survey recommends a Trojan Tour and Rendezvous mission as high-priority among medium-class missions. A dedicated mission to the Trojan asteroids could confirm or refute multiple theories to correctly explain the Trojan asteroids' current location, characteristics, and behavior. In-depth and conclusive evidence for the Trojan asteroids' internal and external make-up as well as dynamical behavior hav been challenging due to limitations of ground- and space-based observations. Notwithstanding these limitations, it has been inferred that there are two distinct sub- populations that are distinguishable in visible and near-infrared spectra (redder and less red) within the swarms. These spectral groupings have not yet been conclusively linked to physical characteristics (e.g. size) or other observed parameters (e.g. albedo) of the primordial bodies. NASA's Jet Propulsion Laboratory's concept studies for Decadal Survey evaluated three concepts for missions to Trojan asteroids: each utilizing chemical- solar-electric, and radioisotope-electric for propulsion. Both Solar and Advanced Stirling Radioisotope Generators were considered for power [2]. We present a new conceptual mission to explore the Trojan asteroids that achieves the science goals prioritized in the 2013 Planetary Science Decadal Survey. The proposed mission aims to study both a redder and less red asteroid for the surface mineralogical and elemental composition, state of surface regolith, evidence and consequences of external modification processes such as collisional evolution, space weathering, and irradiation. Some potential targets in the L4 Greek camp currently under consideration for this mission include Achilles, Hektor and Agamemnon (redder) and Eurybates, Deipylos and Kalchas (less

  7. The EJSM Jupiter-Europa Orbiter: Science Objectives

    Science.gov (United States)

    Pappalardo, R. T.; Blanc, M.; Clark, K.; Greeley, R.; Hendrix, A. R.; Lebreton, J.-P.

    2008-09-01

    Europa is believed to shelter an ocean between its geodynamically active icy shell and its rocky mantle, where the conditions for habitability may be fulfilled. With a warm, salty, water ocean and plausible chemical energy sources, Europa is the astrobiological archetype for icy satellite habitability. It is also a geophysical wonderland of interrelated ice shell processes that are intimately related to the ocean and tides, and of complex interactions among its interior, surface, atmosphere, and magnetospheric environments. The Jupiter-Europa Orbiter (JEO) is one component of the proposed multi-spacecraft Europa Jupiter System Mission (EJSM). We focus here on the science objectives and heritage of JEO.

  8. Unmasking Europa the search for life on Jupiter's ocean moon

    CERN Document Server

    Greenberg, Richard

    2008-01-01

    Jupiter's ice moon Europa is widely regarded as the most likely place to find extraterrestrial life. This book tells the engaging story of Europa, the oceanic moon. It features a large number of stunning images of the ocean moon's surface, clearly displaying the spectacular crack patterns, extensive rifts and ridges, and refrozen pools of exposed water filled with rafts of displaced ice. Coverage also features firsthand accounts of Galileo's mission to Jupiter and its moons. The book tells the rough and tumble inside story of a very human enterprise in science that lead to the discovery of a f

  9. New Horizons Pluto Flyby Guest Operations

    Science.gov (United States)

    Simon, M.; Turney, D.; Fisher, S.; Carr, S. S.

    2015-12-01

    On July 14, 2015, after 9.5 years of cruise, NASA's New Horizons spacecraft flew past the Pluto system to gather first images humankind had ever seen on Pluto and its five moons. While much has been discovered about the Pluto system since New Horizons launch in 2006, the system has never been imaged at high resolution and anticipation of the "First Light" of the Pluto system had been anticipated by planetary enthusiasts for decades. The Johns Hopkins Applied Physics Laboratory (APL), which built and operates New Horizons, was the focal point for gathering three distinct groups: science and engineering team members; media and public affairs representatives; and invited public, including VIP's. Guest operations activities were focused on providing information primarily to the invited public and VIP's. High level objectives for the Guest Operations team was set to entertain and inform the general public, offer media reaction shots, and to deconflict activities for the guests from media activities wherever possible. Over 2000 people arrived at APL in the days surrounding closest approach for guest, science or media operations tracks. Reaction and coverage of the Guest Operations events was universally positive and global in impact: iconic pictures of the auditorium waving flags during the moment of closest approach were published in media outlets on every continent. Media relations activities ensured coverage in all key media publications targeted for release, such as the New York Times, Science, Le Monde, and Nature. Social and traditional media coverage of the events spanned the globe. Guest operations activities are designed to ensure that a guest has a memorable experience and leaves with a lifelong memory of the mission and their partnership in the activity. Results, lessons learned, and other data from the New Horizons guest operations activity will be presented and analyzed.

  10. Three spacecraft observe Jupiter's glowing polar regions

    Science.gov (United States)

    1996-09-01

    again in 1994, when the fragments of Comet Shoemaker-Levy 9 hit Jupiter in a spectacular series of events. The explosive impacts appeared to repress the auroral activity at the time, suggesting a remarkable effect of comet dust on the charged particles creating the aurorae in Jupiter's atmosphere. The new results on variability due to other causes will help astronomers to assess that effect more confidently. They will also compare the 1994 and 1996 IUE data to see how the atmosphere of Jupiter has recovered from the impacts. In Jupiter's vicinity IUE registered ultraviolet emissions from oxygen and sulphur atoms littering the orbit of Io, and probably released by volcanic emissions from that peculiar moon. This Io Torus is highly variable too. The record of its ultraviolet emissions, both within the 1996 campaign and in comparison with earlier observations, will help the astronomers to understand the reasons for the variations. A remarkable history The close scrutiny of Jupiter and its moons was the final astronomical task of IUE, before the termination of space operations on 30 September 1996. Over the past few months the IUE science team and collaborating astronomers in Europe have fulfilled a wish-list of important observations precluded by the intense demands on their ultraviolet space observatory throughout its life of nearly nineteen years. The observations in the final science programme confirmed and extended IUE's record, as the most reliable and productive astronomical satellite that ever flew. In March of this year the spacecraft was ailing, with only one of its six gyros still functioning, which severely limited the scope of its original mission. By skillful control and spacecraft engineering it went on harvesting new data, including prolonged observations of Comet Hyakutake. The concluding campaigns that began in April targeted the gamma-ray emitting "blazar" Markarian 421, various other active galaxies, and stellar winds, as well as Jupiter. "I am sad but

  11. A note on the ring current in Saturn’s magnetosphere: Comparison of magnetic data obtained during the Pioneer-11 and Voyager-1 and -2 fly-bys

    Directory of Open Access Journals (Sweden)

    E. J. Bunce

    Full Text Available We examine the residual (measured minus internal magnetic field vectors observed in Saturn’s magnetosphere during the Pioneer-11 fly-by in 1979, and compare them with those observed during the Voyager-1 and -2 fly-bys in 1980 and 1981. We show for the first time that a ring current system was present within the magnetosphere during the Pioneer-11 encounter, which was qualitatively similar to those present during the Voyager fly-bys. The analysis also shows, however, that the ring current was located closer to the planet during the Pioneer-11 encounter than during the comparable Voyager-1 fly-by, reflecting the more com-pressed nature of the magnetosphere at the time. The residual field vectors have been fit using an adaptation of the current system proposed for Jupiter by Connerney et al. (1981a. A model that provides a reasonably good fit to the Pioneer-11 Saturn data extends radially between 6.5 and 12.5 RS (compared with a noon-sector magnetopause distance of 17 RS, has a north-south extent of 4 RS, and carries a total current of 9.6 MA. A corresponding model that provides a qualitatively similar fit to the Voyager data, determined previously by Connerney et al. (1983, extends radially between 8 and 15.5 RS (compared with a noon-sector magnetopause distance for Voyager-1 of 23–24 RS, has a north-south extent of 6 RS, and carries a total current of 11.5 MA.

    Key words. Magnetospheric physics (current systems, magnetospheric configuration and dynamics, planetary magnetospheres

  12. LIFE: Life Investigation For Enceladus A Sample Return Mission Concept in Search for Evidence of Life.

    Science.gov (United States)

    Tsou, Peter; Brownlee, Donald E; McKay, Christopher P; Anbar, Ariel D; Yano, Hajime; Altwegg, Kathrin; Beegle, Luther W; Dissly, Richard; Strange, Nathan J; Kanik, Isik

    2012-08-01

    Life Investigation For Enceladus (LIFE) presents a low-cost sample return mission to Enceladus, a body with high astrobiological potential. There is ample evidence that liquid water exists under ice coverage in the form of active geysers in the "tiger stripes" area of the southern Enceladus hemisphere. This active plume consists of gas and ice particles and enables the sampling of fresh materials from the interior that may originate from a liquid water source. The particles consist mostly of water ice and are 1-10 μ in diameter. The plume composition shows H(2)O, CO(2), CH(4), NH(3), Ar, and evidence that more complex organic species might be present. Since life on Earth exists whenever liquid water, organics, and energy coexist, understanding the chemical components of the emanating ice particles could indicate whether life is potentially present on Enceladus. The icy worlds of the outer planets are testing grounds for some of the theories for the origin of life on Earth. The LIFE mission concept is envisioned in two parts: first, to orbit Saturn (in order to achieve lower sampling speeds, approaching 2 km/s, and thus enable a softer sample collection impact than Stardust, and to make possible multiple flybys of Enceladus); second, to sample Enceladus' plume, the E ring of Saturn, and the Titan upper atmosphere. With new findings from these samples, NASA could provide detailed chemical and isotopic and, potentially, biological compositional context of the plume. Since the duration of the Enceladus plume is unpredictable, it is imperative that these samples are captured at the earliest flight opportunity. If LIFE is launched before 2019, it could take advantage of a Jupiter gravity assist, which would thus reduce mission lifetimes and launch vehicle costs. The LIFE concept offers science returns comparable to those of a Flagship mission but at the measurably lower sample return costs of a Discovery-class mission.

  13. Mercury's Atmosphere and Magnetosphere: MESSENGER Third Flyby Observations

    Science.gov (United States)

    Slavin, James A.; Anderson, Brian J.; Baker, Daniel N.; Benna, Mehdi; Johnson, Catherine L.; Gloeckler, George; Killen, Rosemary M.; Krimigis, Stamatios M.; McClintock, William; McNutt, Ralph L., Jr.; Schriver, David; Solomon, Sean C.; Sprague, Ann L.; Vevack, Ronald J., Jr.; Zurbuchen, Thomas H.

    2009-01-01

    MESSENGER's third flyby of Mercury en route to orbit insertion about the innermost planet took place on 29 September 2009. The earlier 14 January and 6 October 2008 encounters revealed that Mercury's magnetic field is highly dipolar and stable over the 35 years since its discovery by Mariner 10; that a structured, temporally variable exosphere extends to great altitudes on the dayside and forms a long tail in the anti-sunward direction; a cloud of planetary ions encompasses the magnetosphere from the dayside bow shock to the downstream magnetosheath and magnetotail; and that the magnetosphere undergoes extremely intense magnetic reconnect ion in response to variations in the interplanetary magnetic field. Here we report on new results derived from observations from MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer (MASCS), Magnetometer (MAG), and Energetic Particle and Plasma Spectrometer (EPPS) taken during the third flyby.

  14. The flyby anomaly: A case for strong gravitomagnetism ?

    CERN Document Server

    Acedo, L

    2015-01-01

    In the last two decades an anomalous variation in the asymptotic velocity of spacecraft performing a flyby manoeuvre around Earth has been discovered through careful Doppler tracking and orbital analysis. No viable hypothesis for a conventional explanation of this effect has been proposed and its origin remains unexplained. In this paper we discuss a strong transversal component of the gravitomagnetic field as a possible source of the flyby anomaly. We show that the perturbations induced by such a field could fit the anomalies both in sign and order of magnitude. But, although the secular contributions to the Gravity Probe B experimental results and the Lense-Thirring effect in geodynamics satellites can be made null, the detailed orbital evolution is easily in conflict with such an enhanced gravitomagnetic effect.

  15. Dione flybys in the view of energetic particles

    Science.gov (United States)

    Krupp, Norbert; Roussos, Elias; Kriegel, Henrik; Kollmann, Peter; Kivelson, Margaret G.; Kotova, Anna; Regoli, Leonardo; Paranicas, Christopher P.; Mitchell, Don; Krimigis, Stamatios M.; Khurana, Krishan

    2016-10-01

    We report on the results of energetic electron measurements above 15 keV from the Low Energy Magnetospheric Measurement System LEMMS, part of the Magnetospheric Imaging Instrument MIMI onboard Cassini during the five close Dione flybys combined with measurements of the magnetometer instrument MAG - an update of the paper by Krupp et al. 2013. We found particles in the vicinity of Dione bouncing and drifting in Saturn's magnetosphere and eventually are lost onto the surface of the moon. The location and depth of the absorption signature depends on species, their energy and on the geometry of the flyby. For the upstream encounter D1 energy-dependent ion absorption signatures were measured with the evidence that protons present in the upstream region can explain the observed dropout features. The flybys D2 and D3 went through the moon's geometrical wake and we observed energy dependent asymmetric absorption signatures in the fluxes of electrons between the planetward and anti-planetward sectors of the moon's wake at energies above about 100 keV. The most recent flybys D4 and D5 went directly over the north pole of the moon and showed absorption signatures when connected with the moon's flux tube. Trajectory tracings in a simulated environment of Dione's magnetospheric interaction using the Adaptive hybrid model for space plasma simulations (A.I.K.E.F.) indicate that the magnetic and electric field perturbations in Dione's interaction region, as well as magnetospheric diffusion need to be taken into account in order to explain the features in the data.

  16. Design of Round-trip Trajectories to Near-Earth Asteroids Utilizing a Lunar Flyby

    Science.gov (United States)

    Hernandez, Sonia; Barbee, Brent W.

    2011-01-01

    There are currently over 7,700 known Near-Earth Asteroids (NEAs), and more are being discovered on a continual basis. Current models predict that the actual order of magnitude of the NEA population may range from 10' to 10 6 . The close proximity of NEA orbits to Earth's orbit makes it possible to design short duration round-trip trajectories to NEAs under the proper conditions. In previous work, 59 potentially accessible NEAs were identified for missions that depart Earth between the years 2016 and 2050 and have round-trip flight times of a year or less. We now present a new method for designing round-trip trajectories to NEAs in which the Moon's gravity aids the outbound trajectory via a lunar flyby. In some cases this gravity assist can reduce the overall spacecraft propellant required for the mission, which in turn can allow NEAs to be reached which would otherwise be inaccessible to a given mission architecture. Results are presented for a specific case study on NEA 2003 LN6.

  17. The Flyby Anomaly in an Extended Whitehead’s Theory

    Directory of Open Access Journals (Sweden)

    Luis Acedo

    2015-07-01

    Full Text Available In this paper, we consider an extended version of Whitehead’s theory of gravity in connection with the flyby anomaly. Whitehead’s theory is a linear approximation defined in a background Minkowski spacetime, which gives the same solutions as standard general relativity for the Schwarzschild and Kerr metrics cast in Kerr–Schild coordinates. For a long time and because it gives the same results for the three classical tests—perihelion advance, light bending and gravitational redshift—it was considered a viable alternative to general relativity, but as it is really a linear approximation, it fails in more stringent tests. The model considered in this paper is a formal generalization of Whitehead’s theory, including all possible bilinear forms. In the resulting theory, a circulating vector field of force in the low velocities’ approximation for a rotating planet is deduced, in addition to Newtonian gravity. This extra force gives rise to small variations in the asymptotic velocities of flybys around the Earth to be compared to the recently reported flyby anomaly.

  18. Jupiter: Lord of the Planets.

    Science.gov (United States)

    Kaufmann, William

    1984-01-01

    Presents a chapter from an introductory college-level astronomy textbook in which full-color photographs and numerous diagrams highlight an extensive description of the planet Jupiter. Topics include Jupiter's geology, rotation, magnetic field, atmosphere (including clouds and winds), and the Great Red Spot. (DH)

  19. Processing tools refinement for the JIRAM arrival to Jupiter

    Science.gov (United States)

    Moriconi, Maria L.; Noschese, R.; Adriani, A.

    2017-05-01

    The JUNO mission, launched on August 2011 with the goal of investigating the origin and evolution of Jupiter, reached Jupiter in July 2016. The months preceding the JUNO orbit insertion have been crucial for all the instrument teams to check the status and working abilities of the respective experiments. JIRAM (Jupiter Infrared Auroral Mapper), with its imager and slit spectrometer operating over the 2-5μm spectral range will attempt to reveal the deep atmospheric composition -3 to 7 bars- in hot spots, to analyze the infrared auroral emissions of the H3 + molecules ionized by the Jovian magnetosphere currents and to detect the morphology and vertical structure of the clouds. Many different processing tools are in preparation to exploit the incoming JIRAM data. Here some results pertaining to the image quality optimization and the visualizations that can be obtained from the spectrometer data management are reported.

  20. Small Friends of Hot Jupiters

    Science.gov (United States)

    Nunez, Luis Ernesto; Johnson, John A.

    2017-01-01

    Hot Jupiters are Jupiter-sized gas giant exoplanets that closely orbit their host star in periods of about 10 days or less. Early models hypothesized that these exoplanets formed away from the star, then over time drifted to their characteristically closer locations. However, new theories predict that Hot Jupiters form at their close proximity during the process of core accretion (Batygin et al. 2015). In fact, a super-Earth and a Neptune-sized exoplanet have already been detected in the Hot Jupiter-hosting star WASP-47 (Becker et al. 2015). We will present our analysis of radial velocity time series plots to determine whether low-mass, short-period planets have been previously overlooked in systems of stars which host Hot Jupiters.The SAO REU program is funded in part by the National Science Foundation REU and Department of Defense ASSURE programs under NSF Grant no. 1262851.

  1. Warm Jupiters are less lonely than hot Jupiters: close neighbours

    CERN Document Server

    Huang, Chelsea X; Triaud, Amaury H M J

    2016-01-01

    Exploiting the Kepler transit data, we uncover a dramatic distinction in the prevalence of sub-Jovian companions, between systems that contain hot Jupiters (periods inward of 10 days) and those that host warm Jupiters (periods between 10 and 200 days). Hot Jupiters as a whole, with the singular exception of WASP-47b, do not have any detectable inner or outer planetary companions (with periods inward of 50 days and sizes down to $2 R_{\\rm Earth}$). Restricting ourselves to inner companions, our limits reach down to $1 R_{\\rm Earth}$. In stark contrast, half of the warm Jupiters are closely flanked by small companions. Statistically, the companion fractions for hot and warm Jupiters are mutually exclusive, in particular in regard to inner companions. The high companion fraction of warm Jupiters also yields clue to their formation. The warm Jupiters that have close-by siblings should have low orbital eccentricities and low mutual inclinations. The orbital configurations of these systems are reminiscent of those ...

  2. LUGH, the Proposed Mercury Express Mission, as an Ideal, Current, Low-Cost, Low-Risk Option for Mercury Exploration

    Science.gov (United States)

    Clark, P. E.; Lawlor, S. McKenna; Curtis, S.; Marr, G.; Giles, B.

    2000-01-01

    We propose an ESA Flexi Mission, LUGH, Mercury Express Mission, an extremely fast, low cost, low risk, high return, three-platform, multiple flyby mission which would provide data which are unique and complimentary to recently selected long lead time Mercury missions.

  3. LUGH, the Proposed Mercury Express Mission, as an Ideal, Current, Low-Cost, Low-Risk Option for Mercury Exploration

    Science.gov (United States)

    Clark, P. E.; Lawlor, S. McKenna; Curtis, S.; Marr, G.; Giles, B.

    2000-01-01

    We propose an ESA Flexi Mission, LUGH, Mercury Express Mission, an extremely fast, low cost, low risk, high return, three-platform, multiple flyby mission which would provide data which are unique and complimentary to recently selected long lead time Mercury missions.

  4. An Impacting Descent Probe for Europa and the Other Galilean Moons of Jupiter

    Science.gov (United States)

    Wurz, P.; Lasi, D.; Thomas, N.; Piazza, D.; Galli, A.; Jutzi, M.; Barabash, S.; Wieser, M.; Magnes, W.; Lammer, H.; Auster, U.; Gurvits, L. I.; Hajdas, W.

    2017-08-01

    We present a study of an impacting descent probe that increases the science return of spacecraft orbiting or passing an atmosphere-less planetary bodies of the solar system, such as the Galilean moons of Jupiter. The descent probe is a carry-on small spacecraft (return to a mission at a low extra level of complexity, engineering effort, and risk. This study builds upon earlier studies for a Callisto Descent Probe for the former Europa-Jupiter System Mission of ESA and NASA, and extends them with a detailed assessment of a descent probe designed to be an additional science payload for the NASA Europa Mission.

  5. Physical properties of the ESA Rosetta target asteroid (21) Lutetia. II. Shape and flyby geometry

    Science.gov (United States)

    Carry, B.; Kaasalainen, M.; Leyrat, C.; Merline, W. J.; Drummond, J. D.; Conrad, A.; Weaver, H. A.; Tamblyn, P. M.; Chapman, C. R.; Dumas, C.; Colas, F.; Christou, J. C.; Dotto, E.; Perna, D.; Fornasier, S.; Bernasconi, L.; Behrend, R.; Vachier, F.; Kryszczynska, A.; Polinska, M.; Fulchignoni, M.; Roy, R.; Naves, R.; Poncy, R.; Wiggins, P.

    2010-11-01

    Aims: We determine the physical properties (spin state and shape) of asteroid (21) Lutetia, target of the International Rosetta Mission of the European Space Agency, to help in preparing for observations during the flyby on 2010 July 10 by predicting the orientation of Lutetia as seen from Rosetta. Methods: We use our novel KOALA inversion algorithm to determine the physical properties of asteroids from a combination of optical lightcurves, disk-resolved images, and stellar occultations, although the last are not available for (21) Lutetia. Results: We find the spin axis of (21) Lutetia to lie within 5° of (λ = 52°, β = -6°) in the Ecliptic J2000 reference frame (equatorial α = 52°, δ = +12°), and determine an improved sidereal period of 8.168 270 ± 0.000 001 h. This pole solution implies that the southern hemisphere of Lutetia will be in “seasonal” shadow at the time of the flyby. The apparent cross-section of Lutetia is triangular when seen “pole-on” and more rectangular “equator-on”. The best-fit model suggests there are several concavities. The largest of these is close to the north pole and may be associated with strong impacts. Based on observations collected at the W. M. Keck Observatory and at European Southern Observatory Very Large Telescope (program ID: 079.C-0493, PI: E. Dotto). The W. M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.Tables 1, 2, 4 and Figs. 3-5 are only available in electronic form at http://www.aanda.org

  6. New Measurements Of Jupiter's Equatorial Region In Visible Wavelengths

    Science.gov (United States)

    Rojas, Jose; Arregi, J.; García-Melendo, E.; Barrado-Izagirre, N.; Hueso, R.; Gómez-Forrellad, J. M.; Pérez-Hoyos, S.; Sanz-Requena, J. F.; Sánchez-Lavega, A.

    2010-10-01

    We have studied the equatorial region of Jupiter, between 15ºS and 15ºN, on Cassini ISS images obtained during the Jupiter flyby at the end of 2000 and on HST images acquired in May and July 2008. We have found significant longitudinal variations in the intensity of the 6ºN eastward jet, up to 60 m s-1 in Cassini and HST observations. In the HST case we found that these longitudinal variations are associated to different cloud morphology. Photometric and radiative transfer analysis of the cloud features used as tracers in HST images shows that there is only a small height difference, no larger than 0.5 - 1 scale heights at most, between the slow ( 100 m s-1) and fast ( 150 m s-1) moving features. This suggests that speed variability at 6ºN is not dominated by vertical wind shears and we propose that Rossby wave activity is the responsible for the zonal variability. After removing this variability we found that Jupiter's equatorial jet is actually symmetric relative to the equator with two peaks of 140 - 150 m s-1 located at latitudes 6ºN and 6ºS and at a similar pressure level. We also studied a large, long-lived feature called the White Spot (WS) located at 6ºS that turns to form and desapear. The internal flow field in the White Spot indicates that it is a weakly rotating quasi-equatorial anticyclone relative to the ambient meridionally sheared flow. Acknowledgements: This work was supported by the Spanish MICIIN AYA2009-10701 with FEDER and Grupos Gobierno Vasco IT-464-07.

  7. Space Radiation Effects and Reliability Consideration for the Proposed Jupiter Europa Orbiter

    Science.gov (United States)

    Johnston, Allan

    2011-01-01

    The proposed Jupiter Europa Orbiter (JEO) mission to explore the Jovian moon Europa poses a number of challenges. The spacecraft must operate for about seven years during the transit time to the vicinity of Jupiter, and then endure unusually high radiation levels during exploration and orbiting phases. The ability to withstand usually high total dose levels is critical for the mission, along with meeting the high reliability standards for flagship NASA missions. Reliability of new microelectronic components must be sufficiently understood to meet overall mission requirements.The proposed Jupiter Europa Orbiter (JEO) mission to explore the Jovian moon Europa poses a number of challenges. The spacecraft must operate for about seven years during the transit time to the vicinity of Jupiter, and then endure unusually high radiation levels during exploration and orbiting phases. The ability to withstand usually high total dose levels is critical for the mission, along with meeting the high reliability standards for flagship NASA missions. Reliability of new microelectronic components must be sufficiently understood to meet overall mission requirements.

  8. Transiting exoplanets from the CoRoT space mission XIV. CoRoT-11b: a transiting massive "hot-Jupiter" in a prograde orbit around a rapidly rotating F-type star

    CERN Document Server

    Gandolfi, D; Alonso, R; Deleuil, M; Guenther, E W; Fridlund, M; Endl, M; Eigmüller, P; Csizmadia, Sz; Havel, M; Aigrain, S; Auvergne, M; Baglin, A; Barge, P; Bonomo, A S; Bordé, P; Bouchy, F; Bruntt, H; Cabrera, J; Carpano, S; Carone, L; Cochran, W D; Deeg, H J; Dvorak, R; Eislöffel, J; Erikson, A; Ferraz-Mello, S; Gazzano, J -C; Gibson, N P; Gillon, M; Gondoin, P; Guillot, T; Hartmann, M; Hatzes, A; Jorda, L; Kabath, P; Léger, A; Llebaria, A; Lammer, H; MacQueen, P J; Mayor, M; Mazeh, T; Moutou, C; Ollivier, M; Pätzold, M; Pepe, F; Queloz, D; Rauer, H; Rouan, D; Samuel, B; Schneider, J; Stecklum, B; Tingley, B; Udry, S; Wuchterl, G; 10.1051/0004-6361/201015132

    2010-01-01

    The CoRoT exoplanet science team announces the discovery of CoRoT-11b, a fairly massive hot-Jupiter transiting a V=12.9 mag F6 dwarf star (M*=1.27 +/- 0.05 Msun, R*=1.37 +/- 0.03 Rsun, Teff=6440 +/- 120 K), with an orbital period of P=2.994329 +/- 0.000011 days and semi-major axis a=0.0436 +/- 0.005 AU. The detection of part of the radial velocity anomaly caused by the Rossiter-McLaughlin effect shows that the transit-like events detected by CoRoT are caused by a planet-sized transiting object in a prograde orbit. The relatively high projected rotational velocity of the star (vsini=40+/-5 km/s) places CoRoT-11 among the most rapidly rotating planet host stars discovered so far. With a planetary mass of mp=2.33+/-0.34 Mjup and radius rp=1.43+/-0.03 Rjup, the resulting mean density of CoRoT-11b (rho=0.99+/-0.15 g/cm^3) can be explained with a model for an inflated hydrogen-planet with a solar composition and a high level of energy dissipation in its interior.

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

    Science.gov (United States)

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

    1996-01-01

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

  10. Emitted Power of Jupiter Based on Cassini CIRS and VIMS Observations

    Science.gov (United States)

    Li, Liming; Baines, Kevin H.; Smith, Mark A.; West, Robert A.; Perez-Hoyos, Santiago; Trammel, Harold J.; Simon-Miller, Amy A.; Conrath, Barney J.; Gierasch, Peter J.; Orton, Glenn S.; hide

    2012-01-01

    The emitted power of Jupiter and its meridional distribution are determined from observations by the Composite Infrared Spectrometer (CIRS) and Visual and Infrared Spectrometer (VIMS) onboard Cassini during its flyby en route to Saturn in late 2000 and early 2001. Jupiter's global- average emitted power and effective temperature are measured to be 14.10+/-0.03 W/sq m and 125.57+/-0.07 K, respectively. On a global scale, Jupiter's 5-micron thermal emission contributes approx. 0.7+/-0.1 % to the total emitted power at the global scale, but it can reach approx. 1.9+/-0.6% at 15degN. The meridional distribution of emitted power shows a significant asymmetry between the two hemispheres with the emitted power in the northern hemisphere 3.0+/-0.3% larger than that in the southern hemisphere. Such an asymmetry shown in the Cassini epoch (2000-01) is not present during the Voyager epoch (1979). In addition, the global-average emitted power increased approx. 3.8+/-1.0% between the two epochs. The temporal variation of Jupiter's total emitted power is mainly due to the warming of atmospheric layers around the pressure level of 200 mbar. The temporal variation of emitted power was also discovered on Saturn (Li et al., 2010). Therefore, we suggest that the varying emitted power is a common phenomenon on the giant planets.

  11. Trojan Tour and Rendezvous (TTR): A New Frontiers Mission to Explore the Origin and Evolution of the Early Solar System

    Science.gov (United States)

    Bell, J. F., III; Olkin, C.; Castillo, J. C.

    2015-12-01

    The orbital properties, compositions, and physical properties of the diverse populations of small outer solar system bodies provide a forensic map of how our solar system formed and evolved. Perhaps the most potentially diagnostic, but least explored, of those populations are the Jupiter Trojan asteroids, which orbit at ~5 AU in the L4 and L5 Lagrange points of Jupiter. More than 6200 Jupiter Trojans are presently known, but these are predicted to be only a small fraction of the 500,000 to 1 million Trojans >1 km in size. The Trojans are hypothesized to be either former Kuiper Belt Objects (KBOs) that were scattered into the inner solar system by early giant planet migration and then trapped in the 1:1 Jupiter mean motion resonance, or bodies formed near 5 AU in a much more quiescent early solar system, and then trapped at L4 and L5. The 2011 Planetary Science Decadal Survey identified important questions about the origin and evolution of the solar system that can be addressed by studying of the Trojan asteroids, including: (a) How did the giant planets and their satellite systems accrete, and is there evidence that they migrated to new orbital positions? (b) What is the relationship between large and small KBOs? Is the small population derived by impact disruption of the large one? (c) What kinds of surface evolution, radiation chemistry, and surface-atmosphere interactions occur on distant icy primitive bodies? And (d) What are the sources of asteroid groups (Trojans and Centaurs) that remain to be explored by spacecraft? The Trojan Tour and Rendezvous (TTR) is a New Frontiers-class mission designed to answer these questions, and to test hypotheses for early giant planet migration and solar system evolution. Via close flybys of a large number of these objects,, and orbital characterization of at least one large Trojan, TTR will enable the first-time exploration of this population. Our primary mission goals are to characterize the overall surface geology

  12. Power-Conversion Concept Designed for the Jupiter Icy Moons Orbiter

    Science.gov (United States)

    Mason, Lee S.

    2004-01-01

    The Jupiter Icy Moons Orbiter (JIMO) is a bold new mission being developed by NASA's Office of Space Science under Project Prometheus. JIMO is examining the potential of nuclear electric propulsion (NEP) technology to efficiently deliver scientific payloads to three of Jupiter's moons: Callisto, Ganymede, and Europa. A critical element of the NEP spacecraft is the space reactor power system (SRPS), consisting of the nuclear reactor, power conversion, heat rejection, and power management and distribution (PMAD).

  13. Mercury's Complex Exosphere: Results from MESSENGER's Third Flyby

    Science.gov (United States)

    Vervack, Ronald J., Jr.; McClintock, William E.; Killen, Rosemary M.; Sprague, Ann L.; Anderson, Brian J.; Burger, Matthew H.; Bradley, E. Todd; Mouawad, Nelly; Solomon, Sean C.; Izenberg, Noam R.

    2010-01-01

    During MESSENGER's third flyby of Mercury, the Mercury Atmospheric and Surface Composition Spectrometer detected emission from ionized calcium concentrated 1 to 2 Mercury radii tailward of the planet. This measurement provides evidence for tailward magnetospheric convection of photoions produced inside the magnetosphere. Observations of neutral sodium, calcium, and magnesium above the planet's north and south poles reveal attitude distributions that are distinct for each species. A two-component sodium distribution and markedly different magnesium distributions above the two poles are direct indications that multiple processes control the distribution of even single species in Mercury's exosphere,

  14. Mercury's complex exosphere: results from MESSENGER's third flyby.

    Science.gov (United States)

    Vervack, Ronald J; McClintock, William E; Killen, Rosemary M; Sprague, Ann L; Anderson, Brian J; Burger, Matthew H; Bradley, E Todd; Mouawad, Nelly; Solomon, Sean C; Izenberg, Noam R

    2010-08-06

    During MESSENGER's third flyby of Mercury, the Mercury Atmospheric and Surface Composition Spectrometer detected emission from ionized calcium concentrated 1 to 2 Mercury radii tailward of the planet. This measurement provides evidence for tailward magnetospheric convection of photoions produced inside the magnetosphere. Observations of neutral sodium, calcium, and magnesium above the planet's north and south poles reveal altitude distributions that are distinct for each species. A two-component sodium distribution and markedly different magnesium distributions above the two poles are direct indications that multiple processes control the distribution of even single species in Mercury's exosphere.

  15. Mercury's Complex Exosphere: Results from MESSENGER's Third Flyby

    Science.gov (United States)

    Vervack, Ronald J., Jr.; McClintock, William E.; Killen, Rosemary M.; Sprague, Ann L.; Anderson, Brian J.; Burger, Matthew H.; Bradley, E. Todd; Mouawad, Nelly; Solomon, Sean C.; Izenberg, Noam R.

    2010-01-01

    During MESSENGER's third flyby of Mercury, the Mercury Atmospheric and Surface Composition Spectrometer detected emission from ionized calcium concentrated 1 to 2 Mercury radii tailward of the planet. This measurement provides evidence for tailward magnetospheric convection of photoions produced inside the magnetosphere. Observations of neutral sodium, calcium, and magnesium above the planet's north and south poles reveal attitude distributions that are distinct for each species. A two-component sodium distribution and markedly different magnesium distributions above the two poles are direct indications that multiple processes control the distribution of even single species in Mercury's exosphere,

  16. Jupiter Clouds in Depth

    Science.gov (United States)

    2000-01-01

    [figure removed for brevity, see original site] 619 nm [figure removed for brevity, see original site] 727 nm [figure removed for brevity, see original site] 890 nmImages from NASA's Cassini spacecraft using three different filters reveal cloud structures and movements at different depths in the atmosphere around Jupiter's south pole.Cassini's cameras come equipped with filters that sample three wavelengths where methane gas absorbs light. These are in the red at 619 nanometer (nm) wavelength and in the near-infrared at 727 nm and 890 nm. Absorption in the 619 nm filter is weak. It is stronger in the 727 nm band and very strong in the 890 nm band where 90 percent of the light is absorbed by methane gas. Light in the weakest band can penetrate the deepest into Jupiter's atmosphere. It is sensitive to the amount of cloud and haze down to the pressure of the water cloud, which lies at a depth where pressure is about 6 times the atmospheric pressure at sea level on the Earth). Light in the strongest methane band is absorbed at high altitude and is sensitive only to the ammonia cloud level and higher (pressures less than about one-half of Earth's atmospheric pressure) and the middle methane band is sensitive to the ammonia and ammonium hydrosulfide cloud layers as deep as two times Earth's atmospheric pressure.The images shown here demonstrate the power of these filters in studies of cloud stratigraphy. The images cover latitudes from about 15 degrees north at the top down to the southern polar region at the bottom. The left and middle images are ratios, the image in the methane filter divided by the image at a nearby wavelength outside the methane band. Using ratios emphasizes where contrast is due to methane absorption and not to other factors, such as the absorptive properties of the cloud particles, which influence contrast at all wavelengths.The most prominent feature seen in all three filters is the polar stratospheric haze that makes Jupiter bright near the pole

  17. Jupiter Eruptions Captured in Infrared

    Science.gov (United States)

    2008-01-01

    [figure removed for brevity, see original site] Click on the image for high resolution image of Nature Cover Detailed analysis of two continent-sized storms that erupted in Jupiter's atmosphere in March 2007 shows that Jupiter's internal heat plays a significant role in generating atmospheric disturbances. Understanding these outbreaks could be the key to unlock the mysteries buried in the deep Jovian atmosphere, say astronomers. This infrared image shows two bright plume eruptions obtained by the NASA Infrared Telescope Facility on April 5, 2007. Understanding these phenomena is important for Earth's meteorology where storms are present everywhere and jet streams dominate the atmospheric circulation. Jupiter is a natural laboratory where atmospheric scientists study the nature and interplay of the intense jets and severe atmospheric phenomena. According to the analysis, the bright plumes were storm systems triggered in Jupiter's deep water clouds that moved upward in the atmosphere vigorously and injected a fresh mixture of ammonia ice and water about 20 miles (30 kilometers) above the visible clouds. The storms moved in the peak of a jet stream in Jupiter's atmosphere at 375 miles per hour (600 kilometers per hour). Models of the disturbance indicate that the jet stream extends deep in the buried atmosphere of Jupiter, more than 60 miles (approximately100 kilometers) below the cloud tops where most sunlight is absorbed.

  18. MESSENGER Measurements of Mercury's Magnetic Field during the First Flyby

    Science.gov (United States)

    Slavin, James A.; Boardsen, S. A.; Acuna, M. H.; Anderson, B. J.; Johnson, C. L.; Korth, H.; Krimigis, S. M.; McNutt, R. L., Jr.; Purucker, M. E.; Solomon, S. C.

    2008-01-01

    On 14 January 2008 the MESSENGER spacecraft will encounter Mercury for the first time. Depending upon the solar wind conditions, this initial flyby will return Magnetometer measurements of Mercury's magnetic field over a time interval lasting between - 30 md 60 min. Closest approach for MESSENGER is targeted for an altitude of 200 km as compared with the 707 krn and 327 km attained by Mariner 10 on 29 March 1974 and 16 March 1975, respectively. Furthermore, the differences in the MESSENGER and Mariner 10 encounter trajectories, with respect both to magnetospheric and body-fixed coordinates are highly complementary and expected to lead to significant improvements in our knowledge of Mercury's magnetic field. We present an overview of the MESSENGER magnetic field observations, an initial subtraction of the magnetic fields attributable to magnetospheric current systems from the total measured magnetic field, and an improved model of Mercury's intrinsic magnetic field. We also discuss the expected advances afforded by the two additional MESSENGER flybys, which occur in October 2008 and September 2009, as well as the orbital phase that will begin in March 201 1.

  19. Atmospheric Circulation on Hot Jupiters: Modeling and Observable Signatures

    Science.gov (United States)

    Rauscher, Emily Christine

    2010-12-01

    Hot Jupiters are unlike any planets in our Solar System and yet one of the most common types of extrasolar planet discovered. These gas giants orbit their parent stars with periods of a few days. Expected to be tidally locked into synchronous rotation, hot Jupiters experience intense, asymmetric heating from stellar irradiation, such that day-night temperature contrasts could reach hundreds of degrees Kelvin. This unique state of radiative forcing, as well as the slow rotation rates of these planets, places hot Jupiters within a new regime of atmospheric circulation. Hot Jupiters have also been the first type of extrasolar planet with direct detections of their atmospheres, through measurements of emitted, reflected, and transmitted light. This thesis investigates observational methods to distinguish between various atmospheric models, observational signatures of potential atmospheric variability, and presents a three dimensional model with which to study hot Jupiter circulation patterns. First, we find that eclipse mapping is a technique that can be used to image the day sides of these planets and although this is beyond the ability of current instruments, it will be achievable with future missions, such as the James Webb Space Telescope. Second, we consider the signatures of large-scale atmospheric variability in measurements of secondary eclipses and thermal orbital phase curves. For various models we predict the amount of variation in eclipse depth, and the amplitudes and detailed shapes of phase curves. Lastly, we develop a three-dimensional model of hot Jupiter atmospheric dynamics with simplified forcing and adopt a set-up nearly identical to work by another group to facilitate code inter-comparison. Our results are broadly consistent with theirs, with a transonic flow and the hottest region of the atmosphere advected eastward of the substellar point. However, we note important differences and identify areas of concern for future modeling efforts.

  20. Jupiter's Mid-Infrared Aurora: Solar Connection and Minor Constituents

    Science.gov (United States)

    Kostiuk, Theodore; Livengood, T.A.; Fast, K.E.; Hewagama, T.; Schmilling, F.; Sonnabend, G.; Delgado, J.

    2009-01-01

    High spectral resolution in the 12 pin region of the polar regions of Jupiter reveal unique information on auroral phenomena and upper stratospheric composition. Polar aurorae in Jupiter's atmosphere radiate; throughout the electromagnetic spectrum from X-ray through mid-infrared (mid-IR, 5 - 20 micron wavelength). Voyager IRIS data and ground-based. spectroscopic measurements of Jupiter's northern mid-IR aurora acquired since 1982, reveal a correlation between auroral brightness and solar activity that has not been observed in Jovian aurora at other wavelengths. Over nearly three solar cycles, Jupiter auroral ethane, emission brightness and solar 10.7-cm radar flux and sunspot number are positively correlated with high confidence. Ethane line emission intensity varies over tenfold between low and high scalar activity periods. Detailed measurements have been made using the GSFC HIPWAC spectrometer at the NASA IRTF since the last solar maximum, following the mid-IR emission through the declining phase toward solar minimum. An even more convincing correlation with solar activity is evident in these data. The spectra measured contain features that cannot be attributed to ethane and are most likely spectra of minor constituents whose molecular bands overlap the v9 band of ethane. Possible candidates are allene, propane, and other higher order hydrocarbons. These features appear to be enhanced in the active polar regions. Laboratory measurements at comparable spectral resolution of spectra of candidate molecules will be used to identify the constituents. Current analyses of these results will be described, including planned measurements on polar ethane line emission scheduled through the rise of the next solar maximum beginning in 2009, with a steep gradient to a maximum in 2012. This work is relevant to the Juno mission and to the development of the NASA/ESA Europa Jupiter System Mission.

  1. Comparative impactology on Jupiter: Cataloging the clumps

    Science.gov (United States)

    Wong, Michael

    2010-09-01

    Seven months after HubbleA?s first servicing mission, the impact of Comet Shoemaker-Levy 9 {SL9} captured worldwide attentionA?and the newly-installed WFPC2 captured 472 images of Jupiter in Program 5642. We will complete a census of each impact, including evolution, size, morphology, and color, now that the geometric and photometric calibration of WFPC2 has reached its best and final state. The data from Program 5642 prove their great value by still continuing to generate science publications, and we will upload deprojected {latitude-longitude mapped} data as High Level Science Products to further enhance the usability of this unique data set. The WFPC2 data are needed to understand recent observations of the 2009 impact on Jupiter, in which only 36 WFC3 and ACS images were obtained in Program 12003. In the isolated 2009 impact, the debris formed clumps that lasted at least until Jupiter was imaged again on 22 September {Program 11559}, two months after the impact. Clumps were observed in a subset of SL9 impact sites, but a complete survey of all the available WFPC2 impact site imaging data will enable us to measure clump formation, favored dynamical environments, frequency of occurrence, interactions with other Jovian atmospheric features, and rates of change in size and albedo. Based on the 2009 WFC3 and ACS data, we suggest that these clumps are lower stratospheric eddies that maintain aerosol concentrations against dissipation. We will search the proposed complete catalog of 1994 WFPC2 data to isolate the determining factors for the formation and evolution of these clumps, with the goal of finding out whether they are commonplace Jovian dynamical features simply traced by impact-generated aerosols, or unique features generated by the impacts themselves {either through impact-related thermochemical processes, or through differences in particle microphysics}. If the clumps mark commonplace but normally invisible eddies, they may play interesting roles in the

  2. Jupiter's moon Io

    Science.gov (United States)

    1979-01-01

    This picture shows a special color reconstruction of one of the erupting volcanos on Io discovered by Voyager 1 during its encounter with Jupiter on the 4th and 5th of March. The picture was taken March 4 about 5:00 p.m. from a range of about half a million kilometers showing an eruption region on the horizon. This method of color analysis allows scientists to combine data from four pictures, taken in ultraviolet, blue, green and orange light. In this picture one can see the strong change in color of the erupting plume. The region that is brighter in ultraviolet light (blue in this image) is much more extensive than the denser, bright yellow region near the center of the eruption. Scientists will use data of this type to study the amount of gas and dust in the eruption and the size of dust particles. Preliminary analysis suggests that the bright ultraviolet part of the cloud may be due to scattered light from very fine particles (the same effect which makes smoke appear bluish).

  3. Jupiter's Hot, Mushy Moon

    Science.gov (United States)

    Taylor, G. Jeffrey

    2003-01-01

    Jupiter's moon Io is the most volcanically active body in the Solar System. Observations by instruments on the Galileo spacecraft and on telescopes atop Mauna Kea in Hawai'i indicate that lava flows on Io are surprisingly hot, over 1200 oC and possibly as much as 1300 oC; a few areas might have lava flows as hot as 1500 oC. Such high temperatures imply that the lava flows are composed of rock that formed by a very large amount of melting of Io's mantle. This has led Laszlo Keszthelyi and Alfred S. McEwen of the University of Arizona and me to reawaken an old hypothesis that suggests that the interior of Io is a partially-molten mush of crystals and magma. The idea, which had fallen out of favor for a decade or two, explains high-temperature hot spots, mountains, calderas, and volcanic plains on Io. If correct, Io gives us an opportunity to study processes that operate in huge, global magma systems, which scientists believe were important during the early history of the Moon and Earth, and possibly other planetary bodies as well. Though far from proven, the idea that Io has a ocean of mushy magma beneath its crust can be tested with measurements by future spacecraft.

  4. JESTR: Jupiter Exploration Science in the Time Regime

    Science.gov (United States)

    Noll, Keith S.; Simon-Miller, A. A.; Wong, M. H.; Choi, D. S.

    2012-01-01

    Solar system objects are inherently time-varying with changes that occur on timescales ranging from seconds to years. For all planets other than the Earth, temporal coverage of atmospheric phenomena is limited and sparse. Many important atmospheric phenomena, especially those related to atmospheric dynamics, can be studied in only very limited ways with current data. JESTR is a mission concept that would remedy this gap in our exploration of the solar system by ncar-continuous imaging and spectral monitoring of Jupiter over a multi-year mission lifetime.

  5. Tracking and data system support for the Pioneer project. Volume 3: Pioneer 10 from 1 April 1972 through the Jupiter encounter period, January 1974

    Science.gov (United States)

    Miller, R. B.

    1975-01-01

    The Tracking and Data Systems support of the Pioneer 10 mission from April 1, 1972 through the Jupiter encounter period which ended January 5, 1974 is described. The period covered involves operations in the interplanetary environment from the time of completion of the second trajectory correction to the start of Jupiter encounter; the implementation, planning, and testing that lead to the Jupiter encounter; and the operations during the 60 day encounter period.

  6. Galileo's Last Fly-Bys of Io: NIMS Observations of Loki, Tupan, and Emakong Calderas

    Science.gov (United States)

    Lopes, Rosaly M. C.; Kamp, L. W.; Davies, A. G.; Smythe, W. D.; Carlson, R. W.; Doute, S.; McEwen, A.; Turtle, E. P.; Leader, F.; Mehlman, R.

    2002-01-01

    NIMS results from the 2001 Galileo fly-bys of Io will be presented, focusing on three calderas that may contain lava lakes. Preliminary results from the January 2002 Io fly-by will be presented. Additional information is contained in the original extended abstract.

  7. Planetary Radio Interferometry and Doppler Experiment (PRIDE) technique: A test case of the Mars Express Phobos fly-by

    Science.gov (United States)

    Duev, D. A.; Pogrebenko, S. V.; Cimò, G.; Molera Calvés, G.; Bocanegra Bahamón, T. M.; Gurvits, L. I.; Kettenis, M. M.; Kania, J.; Tudose, V.; Rosenblatt, P.; Marty, J.-C.; Lainey, V.; de Vicente, P.; Quick, J.; Nickola, M.; Neidhardt, A.; Kronschnabl, G.; Ploetz, C.; Haas, R.; Lindqvist, M.; Orlati, A.; Ipatov, A. V.; Kharinov, M. A.; Mikhailov, A. G.; Lovell, J. E. J.; McCallum, J. N.; Stevens, J.; Gulyaev, S. A.; Natush, T.; Weston, S.; Wang, W. H.; Xia, B.; Yang, W. J.; Hao, L.-F.; Kallunki, J.; Witasse, O.

    2016-09-01

    Context. The closest ever fly-by of the Martian moon Phobos, performed by the European Space Agency's Mars Express spacecraft, gives a unique opportunity to sharpen and test the Planetary Radio Interferometry and Doppler Experiments (PRIDE) technique in the interest of studying planet-satellite systems. Aims: The aim of this work is to demonstrate a technique of providing high precision positional and Doppler measurements of planetary spacecraft using the Mars Express spacecraft. The technique will be used in the framework of Planetary Radio Interferometry and Doppler Experiments in various planetary missions, in particular in fly-by mode. Methods: We advanced a novel approach to spacecraft data processing using the techniques of Doppler and phase-referenced very long baseline interferometry spacecraft tracking. Results: We achieved, on average, mHz precision (30 μm/s at a 10 s integration time) for radial three-way Doppler estimates and sub-nanoradian precision for lateral position measurements, which in a linear measure (at a distance of 1.4 AU) corresponds to ~50 m.

  8. Planetary Radio Interferometry and Doppler Experiment (PRIDE) technique: A test case of the Mars Express Phobos fly-by

    CERN Document Server

    Duev, Dmitry A; Cimò, Giuseppe; Calvés, Guifré Molera; Bahamón, Tatiana M Bocanegra; Gurvits, Leonid I; Kettenis, Mark M; Kania, Joseph; Tudose, Valeriu; Rosenblatt, Pascal; Marty, Jean-Charles; Lainey, Valery; de Vicente, Pablo; Quick, Jonathan; Nickola, Marisa; Neidhardt, Alexander; Kronschnabl, Gerhard; Plötz, Christian; Haas, Rüdiger; Lindqvist, Michael; Orlati, Andrea; Ipatov, Alexander V; Kharinov, Mikhail A; Mikhailov, Andrey G; Lovell, Jim; McCallum, Jamie; Stevens, Jamie; Gulyaev, Sergei A; Natush, Tim; Weston, Stuart; Wang, Weihua; Xia, Bo; Yang, Wenjun; Hao, Long-Fei; Kallunki, Juha; Witasse, Olivier

    2016-01-01

    The closest ever fly-by of the Martian moon Phobos, performed by the European Space Agency's Mars Express spacecraft, gives a unique opportunity to sharpen and test the Planetary Radio Interferometry and Doppler Experiments (PRIDE) technique in the interest of studying planet - satellite systems. The aim of this work is to demonstrate a technique of providing high precision positional and Doppler measurements of planetary spacecraft using the Mars Express spacecraft. The technique will be used in the framework of Planetary Radio Interferometry and Doppler Experiments in various planetary missions, in particular in fly-by mode. We advanced a novel approach to spacecraft data processing using the techniques of Doppler and phase-referenced very long baseline interferometry spacecraft tracking. We achieved, on average, mHz precision (30 {\\mu}m/s at a 10 seconds integration time) for radial three-way Doppler estimates and sub-nanoradian precision for lateral position measurements, which in a linear measure (at a d...

  9. Generalized flyby trajectories around elongated minor celestial bodies as a rotating mass dipole

    Institute of Scientific and Technical Information of China (English)

    Xiangyuan Zeng; Baodong Fang; Junfeng Li; Yang Yu

    2016-01-01

    The aim of this paper is to understand the com-mon characteristics of the generalized flyby trajectory around natural elongated bodies. Such flyby trajectories provide a short-term mechanism to clear away vicinal objects or temporally capture ejecta into circling orbits. The gravita-tional potential of elongated bodies is described by a unified approximate model, i.e., the rotating mass dipole which is two point masses connected with a constant massless rod. The energy power is used to illustrate the flyby effect in terms of the instantaneous orbital energy. The essential of the single flyby trajectory is studied analytically, and the relationship between the flyby trajectory and its Jacobi integral is also illustrated. Sample trajectories are given to show the varia-tional trend of the energy increment with respect to different orbital periapsides. The distribution of natural ejecting orbits is presented by varying the parameters of the approximate model.

  10. EJSM Radar instruments: Natural radio noise from Jupiter

    Science.gov (United States)

    Cecconi, Baptiste; Hess, Sébastien; Zarka, Philippe; Blankenship, Donald; Bruzzone, Lorenzo; Santos-Costa, Daniel; Bougeret, Jean-Louis

    2010-05-01

    Radar instruments are part of the core payload of the Europa Jupiter System Mission (EJSM) spacecraft: NASA- led JEO (Jupiter Europa Orbiter) and ESA-led JGO (Jupiter Ganymede Orbiter). At this point of the project, several frequency bands are foreseen for radar studies between 5MHz and 50MHz. While the high frequencies (40 to 50 MHz) are clean bands since natural jovian radio emissions show a high frequency cutoff at about 40 MHz, lower frequencies are right in the middle of the intense decametric (DAM) radio emissions. We present a review of spectral intensity, variability and sources of these radio emissions. As the radio emission are beamed, it is possible to model the visibility of the radio emissions, as seen from the vicinity of Europa or Ganymede. We have investigated Io-related radio emissions as well as radio emissions related to the auroral oval. One result from these simulations is that some portion of the orbit of Europa is clean from Non-Io DAM emissions above 22 MHz. We also review the radiation belts synchrotron emission characteristics. This study clearly shows that a deep understanding of the natural radio emissions at Jupiter is necessary to prepare the future EJSM radar instrumentation.

  11. Types of Hot Jupiter Atmospheres

    Science.gov (United States)

    Bisikalo, Dmitry V.; Kaygorodov, Pavel V.; Ionov, Dmitry E.; Shematovich, Valery I.

    Hot Jupiters, i.e. exoplanet gas giants, having masses comparable to the mass of Jupiter and semimajor axes shorter than 0.1 AU, are a unique class of objects. Since they are so close to the host stars, their atmospheres form and evolve under the action of very active gas dynamical processes caused by the gravitational field and irradiation of the host star. As a matter of fact, the atmospheres of several of these planets fill their Roche lobes , which results in a powerful outflow of material from the planet towards the host star. The energy budget of this process is so important that it almost solely governs the evolution of hot Jupiters gaseous envelopes. Based on the years of experience in the simulations of gas dynamics in mass-exchanging close binary stars, we have investigated specific features of hot Jupiters atmospheres. The analytical estimates and results of 3D numerical simulations, discussed in this Chapter, show that the gaseous envelopes around hot Jupiters may be significantly non-spherical and, at the same time, stationary and long-lived. These results are of fundamental importance for the interpretation of observational data.

  12. Jupiter and Saturn Rotation Periods

    CERN Document Server

    Helled, Ravit; Anderson, John D

    2009-01-01

    Anderson & Schubert (2007, Science,317,1384) proposed that Saturn's rotation period can be ascertained by minimizing the dynamic heights of the 100 mbar isosurface with respect to the geoid; they derived a rotation period of 10h 32m 35s. We investigate the same approach for Jupiter to see if the Jovian rotation period is predicted by minimizing the dynamical heights of its isobaric (1 bar pressure level) surface using zonal wind data. A rotation period of 9h 54m 29s is found. Further, we investigate the minimization method by fitting Pioneer and Voyager occultation radii for both Jupiter and Saturn. Rotation periods of 9h 55m 30s and 10h 32m 35s are found to minimize the dynamical heights for Jupiter and Saturn, respectively. Though there is no dynamical principle requiring the minimization of the dynamical heights of an isobaric surface, the successful application of the method to Jupiter lends support to its relevance for Saturn. We derive Jupiter and Saturn rotation periods using equilibrium theory in ...

  13. Cassini Solstice Mission Maneuver Experience: Year Three

    Science.gov (United States)

    Wagner, Sean V.; Arrieta, Juan; Hahn, Yungsun; Stumpf, Paul W.; Valerino, Powtawche N.; Wong, Mau C.

    2013-01-01

    The Solstice Mission is the final extension of the Cassini spacecraft s tour of Saturn and its moons. To accommodate an end-of-mission in 2017, the maneuver decision process has been refined. For example, the Cassini Project now prioritizes saving propellant over minimizing maneuver cycles. This paper highlights 30 maneuvers planned from June 2012 through July 2013, targeted to nine Titan flybys and the final Rhea encounter in the mission. Of these maneuvers, 90% were performed to maintain the prescribed trajectory and preserve downstream delta V. Recent operational changes to maneuver executions based on execution-error modeling and analysis are also discussed.

  14. Generation of highly inclined protoplanetary discs through single stellar flybys

    CERN Document Server

    Xiang-Gruess, Meng

    2015-01-01

    We study the three-dimensional evolution of a viscous protoplanetary disc which is perturbed by a passing star on a parabolic orbit. The aim is to test whether a single stellar flyby is capable to excite significant disc inclinations which would favour the formation of so-called misaligned planets. We use smoothed particle hydrodynamics to study inclination, disc mass and angular momentum changes of the disc for passing stars with different masses. We explore different orbital configurations for the perturber's orbit to find the parameter spaces which allow significant disc inclination generation. Prograde inclined parabolic orbits are most destructive leading to significant disc mass and angular momentum loss. In the remaining disc, the final disc inclination is only below $20^\\circ$. This is due to the removal of disc particles which have experienced the strongest perturbing effects. Retrograde inclined parabolic orbits are less destructive and can generate disc inclinations up to $60^\\circ$. The final disc...

  15. The Gravity Field of Enceladus from the three Cassini Flybys

    Science.gov (United States)

    Iess, L.; Parisi, M.; Ducci, M.; Jacobson, R. A.; Armstrong, J. W.; Asmar, S. W.; Lunine, J. I.; Stevenson, D. J.; Tortora, P.

    2013-12-01

    The Cassini spacecraft carried out gravity measurements of the small Saturnian moon Enceladus during three close flybys on April 28, 2010, November 30, 2010 and May 2, 2012 (designated E9, E12 and E19), at the low altitudes of 100, 48 and 70 km to maximize the accelerations exerted by the moon on the spacecraft. The goals of these observations were the determination of the gravitational quadrupole and the search for a North-South asymmetry in the gravity field, controlled primarily by the spherical harmonic coefficient C30. The estimation of Enceladus' gravity field is especially complex because of the small surface gravity (0.11 m/s2), the short duration of the gravitational interaction and the small number of available flybys. In addition to the gravitational accelerations, the spacecraft was also subject to small but non-negligible drag when it flew through the plume emitted from the south pole of the satellite. This effect occurred during the two south polar flybys E9 and E19. The inclusion of these non-gravitational accelerations proved to be crucial to attain a stable solution for the gravity field. Our estimation relied entirely on precise range rate measurements enabled by a coherent, two-way, microwave link at X-band (7.2-8.4 GHz). Measurement accuracies of 10 micron/s at 60 s integration times were attained under favorable conditions, thanks also to an advanced tropospheric calibration system. The data were fitted using the MONTE orbit determination code, recently developed by JPL for deep space navigation. In addition to the satellite degree 2 gravity field and C30, the solution included the state vector of the spacecraft (one for each flyby) and corrections to the mass and the initial orbital elements of Enceladus. The effect of the drag in E9 and E19 was modeled either as an unknown, impulsive, vectorial delta-V at closest approach, or by using density profiles from models of the plume and solving for the aerodynamic coefficient of the spacecraft. Both

  16. Galileo Mission Science Briefing

    Science.gov (United States)

    1989-07-01

    The first of two tapes of the Galileo Mission Science press briefing is presented. The panel is moderated by George Diller from the Kennedy Space Center (KSC) Public Affairs Office. The participants are John Conway, the director of Payload and operations at Kennedy; Donald E. Williams, Commander of STS-43, the shuttle mission which will launch the Galileo mission; John Casani, the Deputy Assistant Director of Flight Projects at the Jet Propulsion Lab (JPL); Dick Spehalski, Galileo Project Manager at JPL; and Terrence Johnson, Galileo Project Scientist at JPL. The briefing begins with an announcement of the arrival of the Galileo Orbiter at KSC. The required steps prior to the launch are discussed. The mission trajectory and gravity assists from planetary and solar flybys are reviewed. Detailed designs of the orbiter are shown. The distance that Galileo will travel from the sun precludes the use of solar energy for heat. Therefore Radioisotope heater units are used to keep the equipment at operational temperature. A video of the arrival of the spacecraft at KSC and final tests and preparations is shown. Some of the many science goals of the mission are reviewed. Another video showing an overview of the Galileo mission is presented. During the question and answer period, the issue of the use of plutonium on the mission is broached, which engenders a review of the testing methods used to ensure the safety of the capsules containing the hazardous substance. This video has actual shots of the orbiter, as it is undergoing the final preparations and tests for the mission.

  17. Probe interface design consideration. [for interplanetary spacecraft missions

    Science.gov (United States)

    Casani, E. K.

    1974-01-01

    Interface design between a probe and a spacecraft requires not only technical considerations but also management planning and mission analysis interactions. Two further aspects of importance are the flyby versus the probe trade-off, and the relay link design and data handling optimization.

  18. Robotic planetary science missions enabled with small NTR engine/stage technologies

    Science.gov (United States)

    Borowski, Stanley K.

    1995-10-01

    The high specific impulse (Isp) and engine thrust-to-weight ratio of liquid hydrogen (LH2)-cooled nuclear thermal rocket (NTR) engines makes them ideal for upper stage applications to difficult robotic planetary science missions. A small 15 thousand pound force (klbf) NTR engine using a uranium-zirconium-niobium 'ternary carbide' fuel (Isp approximately 960 seconds at approximately 3025K) developed in the Commonwealth of Independent States (CIS) is examined and its use on an expendable injection stage is shown to provide major increases in payload delivered to the outer planets (Saturn, Uranus, Neptune and Pluto). Using a single 'Titan IV-class' launch vehicle, with a lift capability to low Earth orbit (LEO) of approximately 20 metric tons (t), an expendable NTR upper stage can inject two Pluto 'Fast Flyby' spacecraft (PFF/SC) plus support equipment-combined mass of approximately 508 kg--on high energy, '6.5-9.2 year' direct trajectory missions to Pluto. A conventional chemical propulsion mission would use a liquid oxygen (LOX)/LH2 'Centaur' upper stage and two solid rocket 'kick motors' to inject a single PFF/SC on the same Titan IV launch vehicle. For follow on Pluto missions, the NTR injection stage would utilize a Jupiter 'gravity assist' (JGA) maneuver to launch a LOX/liquid methane (CH4) capture stage (Isp approximately 375 seconds) and a Pluto 'orbiter' spacecraft weighing between approximately 167-312 kg. With chemical propulsion, a Pluto orbiter mission is not a viable option because c inadequate delivered mass. Using a 'standardized' NTR injection stage and the same single Titan IV launch scenario, 'direct flight' (no gravity assist) orbiter missions to Saturn, Uranus and Neptune are also enabled with transit times of 2.3, 6.6, and 12.6 years, respectively. Injected mass includes a storable, nitrogen tetroxide/monomethyl hydrazine (N2O4/MMH) capture stage (Isp approximately 330 seconds) and orbiter payloads 340 to 820% larger than that achievable using a

  19. Photopolarimetry team outer planets mission definition phase

    Science.gov (United States)

    1972-01-01

    The work is reported of the Photopolarimetry Team in identifying scientific objectives for photometer/polarimeter experiments for outer planet flyby missions. A discussion of the scientific objectives which can be attained with a photometer/polarimeter experiment, and summaries of the special studies which were performed for the Photopolarimetry Team are presented along with a description of the photometer/polarimeter design which was developed for the Meteoroid Detection Team.

  20. The Juno and Cassini gravity measurements: probing the interior dynamics of Jupiter and Saturn

    Science.gov (United States)

    Kaspi, Y.; Galanti, E.; Hubbard, W. B.; Davighi, J. E.

    2015-10-01

    During 2016-2017 both the Juno and Cassini spacecraft will enter into close-by polar orbits of Jupiter and Saturn, respectively. Using Doppler tracking from Earth these flybys will allow high precision gravity measurements of these planets [1]. These will include high order gravity harmonics (at least up to J10), and the yet to be measured odd gravity spectrum. As the dynamics of deep flows relate to perturbations in the density of the planets, this data can be used to probe for the first time the atmospheric and interior flows on these planets [4, 5, 8]. Particularly, this may allow addressing one of the longest-standing questions in planetary atmospheric dynamics regarding the depth of the observed strong east-west jets-streams on Jupiter and Saturn. In this talk we review different approaches to analyze the gravity measurements, discuss the proposed models relating the gravity fields to the dynamics, and the implications of the results for understanding the mechanisms governing the interiors and atmospheres of Jupiter and Saturn.

  1. Super-Eccentric Migrating Jupiters

    CERN Document Server

    Socrates, Aristotle; Dong, Subo; Tremaine, Scott

    2011-01-01

    An important class of formation theories for hot Jupiters involves the excitation of extreme orbital eccentricity (e=0.99 or even larger) followed by tidal dissipation at periastron passage that eventually circularizes the planetary orbit at a period less than 10 days. In a steady state, this mechanism requires the existence of a significant population of super-eccentric (e>0.9) migrating Jupiters with long orbital periods and periastron distances of only a few stellar radii. For these super-eccentric planets, the periastron is fixed due to conservation of orbital angular momentum and the energy dissipated per orbit is constant, implying that the rate of change in semi-major axis a is \\dot a \\propto a^0.5 and consequently the number distribution satisfies dN/dlog a\\propto a^0.5. If this formation process produces most hot Jupiters, Kepler should detect several super-eccentric migrating progenitors of hot Jupiters, allowing for a test of high-eccentricity migration scenarios.

  2. SUPER-ECCENTRIC MIGRATING JUPITERS

    Energy Technology Data Exchange (ETDEWEB)

    Socrates, Aristotle; Katz, Boaz; Dong Subo; Tremaine, Scott [Institute for Advanced Study, Princeton, NJ 08540 (United States)

    2012-05-10

    An important class of formation theories for hot Jupiters involves the excitation of extreme orbital eccentricity (e = 0.99 or even larger) followed by tidal dissipation at periastron passage that eventually circularizes the planetary orbit at a period less than 10 days. In a steady state, this mechanism requires the existence of a significant population of super-eccentric (e > 0.9) migrating Jupiters with long orbital periods and periastron distances of only a few stellar radii. For these super-eccentric planets, the periastron is fixed due to conservation of orbital angular momentum and the energy dissipated per orbit is constant, implying that the rate of change in semi-major axis a is a-dot {proportional_to}a{sup 1/2} and consequently the number distribution satisfies dN/d log a{proportional_to}a{sup 1/2}. If this formation process produces most hot Jupiters, Kepler should detect several super-eccentric migrating progenitors of hot Jupiters, allowing for a test of high-eccentricity migration scenarios.

  3. Jupiter: Cosmic Jekyll and Hyde.

    Science.gov (United States)

    Grazier, Kevin R

    2016-01-01

    It has been widely reported that Jupiter has a profound role in shielding the terrestrial planets from comet impacts in the Solar System, and that a jovian planet is a requirement for the evolution of life on Earth. To evaluate whether jovians, in fact, shield habitable planets from impacts (a phenomenon often referred to as the "Jupiter as shield" concept), this study simulated the evolution of 10,000 particles in each of the jovian inter-planet gaps for the cases of full-mass and embryo planets for up to 100 My. The results of these simulations predict a number of phenomena that not only discount the "Jupiter as shield" concept, they also predict that in a Solar System like ours, large gas giants like Saturn and Jupiter had a different, and potentially even more important, role in the evolution of life on our planet by delivering the volatile-laden material required for the formation of life. The simulations illustrate that, although all particles occupied "non-life threatening" orbits at their onset of the simulations, a significant fraction of the 30,000 particles evolved into Earth-crossing orbits. A comparison of multiple runs with different planetary configurations revealed that Jupiter was responsible for the vast majority of the encounters that "kicked" outer planet material into the terrestrial planet region, and that Saturn assisted in the process far more than has previously been acknowledged. Jupiter also tends to "fix" the aphelion of planetesimals at its orbit irrespective of their initial starting zones, which has the effect of slowing their passages through the inner Solar System, and thus potentially improving the odds of accretion of cometary material by terrestrial planets. As expected, the simulations indicate that the full-mass planets perturb many objects into the deep outer Solar System, or eject them entirely; however, planetary embryos also did this with surprising efficiency. Finally, the simulations predict that Jupiter's capacity to

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

    Science.gov (United States)

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

    2010-01-01

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

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

    Science.gov (United States)

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

    2010-01-01

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

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

    CERN Document Server

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

    2010-01-01

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

  7. Project Prometheus and Future Entry Probe Missions

    Science.gov (United States)

    Spilker, Thomas R.

    2005-01-01

    A viewgraph presentation on project Prometheus and future entry probe missions is shown. The topics include: 1) What Is Project Prometheus?; 2) What Capabilities Can Project Prometheus Offer? What Mission Types Are Being Considered?; 3) Jupiter Icy Moons Orbiter (JIMO); 4) How Are Mission Opportunities Changing?; 5) Missions Of Interest a Year Ago; 6) Missions Now Being Considered For Further Study; 7) Galileo-Style (Conventional) Probe Delivery; 8) Galileo-Style Probe Support; 9) Conventional Delivery and Support of Multiple Probes; 10) How Entry Probe Delivery From an NEP Vehicle Is Different; and 11) Concluding Remarks.

  8. Argus: A concept study for an Io observer mission from the 2014 NASA/JPL Planetary Science Summer School

    Science.gov (United States)

    Becerra, Patricio; Holstein-Rathlou, Christina; Hays, Lindsay E.; Keane, James T.; Neveu, Marc; Basu, Ko; Davis, Byron; Mendez-Ramos, Eugina; Nelessen, Adam; Fox, Valerie; Herman, Jonathan F.; Parrish, Nathan L.; Hughes, Andrea C.; Marcucci, Emma; Scheinberg, Aaron; Wrobel, Jonathan S.

    2014-11-01

    Jupiter’s moon Io is the ideal target to study extreme tidal heating and volcanism, two major processes shaping the formation and evolution of planetary bodies. In response to the 2009 New Frontiers Announcement of Opportunity, we propose an Io Observer mission concept named Argus (after the mythical watchman of Io). This concept was developed by the students of the August 2014 session of NASA’s Planetary Science Summer School, together with the Jet Propulsion Laboratory’s Team X.The science objectives of our mission are: (1) study the physical process of tidal heating and its implications for habitability in the Solar System and beyond; (2) investigate active lava flows on Io as an analog for volcanism on early Earth; (3) analyze the interaction between Io and the Jovian system via material exchange and magnetospheric activity; (4) study Io’s chemistry and geologic history to gain insight into the formation and evolution of the Galilean satellites. Our mission consists of a Jupiter-orbiting spacecraft performing ten close flybys of Io. The orbital inclination of ~31 degrees minimizes the total radiation dose received, at the cost of having to perform fast flybys (13 km/s).The instrument payload includes: (1) IGLOO, a multi-band camera for regional (500 m/pixel) and high-resolution (50 m/pixel) imaging; (2) IoLA, a laser altimeter to measure the triaxial shape and diurnal tidal deformation, and topographic profiles of individual surface features; (3) IGNITERS, a thermal emission radiometer/spectrometer to map nighttime temperatures, thermal inertia, and characterize Io’s atmosphere; (4) IoNIS, a near-infrared spectrometer to map global (10 km/pixel) and local (2 km/pixel) surface composition; (5) IoFLEX, a magnetometer and (6) IoPEX, a plasma particle analyzer to characterize the magnetic environment and understand the nature of Io’s induced and possible intrinsic magnetic fields; (7) IRAGE, a gravity science experiment to probe Io’s interior

  9. A mission concept for a Grand Tour of Multiple Asteroid Systems

    Science.gov (United States)

    Marchis, F.; Dankanich, J.; Tricarico, P.; Bellerose, J.

    2009-12-01

    In 1993, the Galileo spacecraft imaged the first companion of asteroid, Dactyl orbiting 243 Ida, a main-belt asteroid. Since then, discoveries have been accumulated thanks to the development of high angular resolution imaging on ground-based telescopes (adaptive optics), radar observations and accurate photometric light curve measurements. To date, 180 companions of small solar system bodies (SSSBs) are known in various populations, including 100 in the asteroid main belt, 33 Near Earth Asteroids, 4 Jupiter-Trojan asteroids and 44 in the Kuiper Belt. Multiple Asteroids have been shown to be complex worlds in their own with a wide range of morphologies, dynamical histories, and structural evolution. To the exception of 243 Ida, no spacecraft has visited any of them. Investigating binary asteroid systems can verify and validate current theories on their formation and on the influence of the sun in their formation (YORP effect) and evolution (space weathering). In particular, assessing the origin of the secondary satellite, if it is of common origin or capture, can provide clue of their formation. To a larger extend, the determination of their nature, scenario formation and evolution are key to understand how planet formation occurred but also to understand i) the population and compositional structure of the SSSB today ii) how the dynamics and collisions modify this structure over time iii) what the physical properties of asteroids are (density, porosity) iv) how the surface modification processes affect our ability to determine this structure (e.g. space weathering). In addition, being able to study these properties on closeby asteroids will give a relative scale accounting for the sizes, shape, rotation periods and cratering rate of these small and young bodies. In the framework of the NASA Discovery program, we propose a mission consisting of a Grand Tour of several multiple asteroid systems, including the flyby of a near earth binary asteroid and the rendezvous

  10. The Morphology of Craters on Mercury: Results from MESSENGER Flybys

    Science.gov (United States)

    Barnouin, Oliver S.; Zuber, Maria T.; Smith, David E.; Neumann, Gregory A.; Herrick, Robert R.; Chappelow, John E.; Murchie, Scott L.; Prockter, Louise M.

    2012-01-01

    Topographic data measured from the Mercury Laser Altimeter (MLA) and the Mercury Dual Imaging System (MDIS) aboard the MESSENGER spacecraft were used for investigations of the relationship between depth and diameter for impact craters on Mercury. Results using data from the MESSENGER flybys of the innermost planet indicate that most of the craters measured with MLA are shallower than those previously measured by using Mariner 10 images. MDIS images of these same MLA-measured craters show that they have been modified. The use of shadow measurement techniques, which were found to be accurate relative to the MLA results, indicate that both small bowl-shaped and large complex craters that are fresh possess depth-to-diameter ratios that are in good agreement with those measured from Mariner 10 images. The preliminary data also show that the depths of modified craters are shallower relative to fresh ones, and might provide quantitative estimates of crater in-filling by subsequent volcanic or impact processes. The diameter that defines the transition from simple to complex craters on Mercury based on MESSENGER data is consistent with that reported from Mariner 10 data.

  11. A flyby anomaly for Juno? Not from standard physics

    CERN Document Server

    Iorio, Lorenzo

    2013-01-01

    An empirical formula recently appeared in the literature to explain the observed anomalies of about $\\Delta\\dot\\rho\\approx 1-10$ mm s$^{-1}$ in the geocentric range-rates $\\dot\\rho$ of the Galileo, NEAR and Rosetta spacecraft at some of their past perigee passages along unbound, hyperbolic trajectories. It predicts an anomaly of the order of $6$ mm s$^{-1}$ for the recent flyby of Juno, occurred on 9 October 2013. Data analyses to confirm or disproof it are currently ongoing. We numerically calculate the impact on the geocentric Juno's range rate of some classical and general relativistic dynamical effects which are either unmodelled or mismodelled to a certain level in the software used to process the data. They are: a) The first even zonal harmonic coefficient $J_2$ of the multipolar expansion of the terrestrial gravitational potential causing orbital perturbations both at the $\\left.{\\rm a}^{'}\\right)$ Newtonian ($J_2$) and at the $\\left. {\\rm a}^{''}\\right)$ first post-Newtonian level ($J_2 c^{-2}$) b) Th...

  12. A Comparison of Nuclear Thermal and Nuclear Electric Propulsion for Interplanetary Missions

    Science.gov (United States)

    2007-11-02

    Lawrence Fall 2004 A comparison is made between nuclear thermal rockets and nuclear powered electric propulsion systems. Complete missions are... thermal rockets and nuclear powered electric propulsion systems. Complete missions are designed to be launched by a single Ariane 5 and fly by Jupiter...electric propulsion in the context of missions to Jupiter and Pluto. There are three different ways to use nuclear power: in a Nuclear Thermal Rocket (NTR

  13. Mission Opportunities for Human Exploration of Nearby Planetary Bodies

    CERN Document Server

    Foster, Cyrus

    2016-01-01

    We characterize mission profiles for human expeditions to near-Earth asteroids, Venus, and Mars. Near-Earth objects (NEOs) are the closest destinations beyond cis-lunar space and present a compelling target with capabilities already under development by NASA and its partners. We present manned NEO mission options that would require between 90 days and one year. We next consider planetary flyby missions for Venus along the lines of plans that were first drafted during the Apollo program for human exploration of Venus. We also characterize a Mars flyby, and a double-flyby variant that would include close passes to both Venus and Mars. Finally, we consider orbital missions to Venus and Mars with capability for rendezvous with Phobos or Deimos. This would be a truly new class of mission for astronauts and could serve as a precursor to a human landing on Mars. We present launch opportunities, transit time, requisite {\\Delta}V, and approximate radiation environment parameters for each mission class. We find that {\\...

  14. Space Weathering Perspectives on Europa Amidst the Tempest of the Jupiter Magnetospheric System

    Science.gov (United States)

    Cooper, J. F.; Hartle, R. E.; Lipatov, A. S.; Sittler, E. C.; Cassidy, T. A.; Ip. W.-H.

    2010-01-01

    Europa resides within a "perfect storm" tempest of extreme external field, plasma, and energetic particle interactions with the magnetospheric system of Jupiter. Missions to Europa must survive, functionally operate, make useful measurements, and return critical science data, while also providing full context on this ocean moon's response to the extreme environment. Related general perspectives on space weathering in the solar system are applied to mission and instrument science requirements for Europa.

  15. Gravimetry, rotation and angular momentum of Jupiter from the Juno Radio Science experiment

    Science.gov (United States)

    Serra, D.; Dimare, L.; Tommei, G.; Milani, A.

    2016-12-01

    Juno is a NASA space mission to Jupiter, arriving at the planet in July 2016. Through accurate Doppler tracking in X and Ka-band, the Radio Science experiment will allow to map Jupiter's gravity field, crucial for the study of the interior structure of the planet. In this paper we describe the results of numerical simulations of this experiment, performed with the ORBIT14 orbit determination software, developed by the Department of Mathematics of the University of Pisa and by the spin-off Space Dynamics Services srl. Our analysis included the determination of Jupiter's gravity field, the Love numbers, the direction of the rotation axis and the angular momentum magnitude, the latter by measuring the Lense-Thirring effect on the spacecraft. As far as the gravity field is concerned, the spherical harmonics coefficients of Jupiter's gravitational potential are highly correlated and the accuracy in the determination of the zonal coefficients of degree ℓ is degraded for ℓ > 15 . We explore the possibility of using a local model, introducing ring-shaped mascons, so as to determine the gravity field of the portion of the spherical surface bounded by latitudes 6°N and 35°N, the latitude belt observed during Juno's pericenter passes. Finally, the determination of Jupiter's angular momentum magnitude turned out to be compromised by the impossibility of separating the effects of the Lense-Thirring acceleration and of a change in Jupiter's rotation axis direction.

  16. A fireball in Jupiter's atmosphere

    Science.gov (United States)

    Cook, A. F.; Duxbury, T. C.

    1981-01-01

    One fireball was photographed during two encounters with Jupiter. Its total luminosity was 120,000 0 mag s (at standard range 100 km). If the luminous efficiency proposed by Cook et al. (1981) for slip flow of a meteoroid in its own vapors is employed, an estimated mass of 11 kg is obtained. A rough absolute magnitude is -12.5. If it is noted that the search was conducted for a total of 223 s during two exposures, a number density near Jupiter of 10 to the -28th/cu cm is estimated for masses of meteoroids of 3 kg and greater. This value is about a factor of six smaller than a rough upper limit reached from an extrapolation from terrestrial observations of meteors and comets.

  17. Thermometric Soots on Hot Jupiters?

    CERN Document Server

    Zahnle, K; Fortney, J J

    2009-01-01

    We use a 1D thermochemical and photochemical kinetics model to predict that the stratospheric chemistry of hot Jupiters should change dramatically as temperature drops from 1200 to 1000 K. At 1200 K methane is too unstable to reach the stratosphere in significant quantities, while thermal decomposition of water is a strong source of OH radicals that oxidize any hydrocarbons that do form to CO and CO$_2$. At 1000 K methane, although very reactive, survives long enough to reach the lower stratosphere, and the greater stability of water coupled with efficient scavenging of OH by H$_2$ raise the effective C/O ratio in the reacting gases above unity. Reduced products such as ethylene, acetylene, and hydrogen cyanide become abundant; such conditions favor polymerization and possible formation of PAHs and soots. Although low temperature is the most important factor favoring hydrocarbons in hot Jupiters, higher rates of vertical mixing and generally lower metallicities also favor organic synthesis. The peculiar prope...

  18. A Study of Jupiter Trojans

    OpenAIRE

    Karlsson, Ola

    2012-01-01

    Jupiter Trojan asteroid dynamics have been studied for a long time but it is only within the last decades that the known population has become large enough to make other studies meaningful. In four articles I have been scratching the surface of the unknown Trojan knowledge space. Paper I presents photometric observations confirming a larger variety in surface redness for the smaller Trojans compared to the larger ones, in line with the groups in the outer main asteroid belt. However, the larg...

  19. Jovian Tour Design for Orbiter and Lander Missions to Europa

    Science.gov (United States)

    Campagnola, Stefano; Buffington, Brent B.; Petropoulos, Anastassios E.

    2013-01-01

    Europa is one of the most interesting targets for solar system exploration, as its ocean of liquid water could harbor life. Following the recommendation of the Planetary Decadal Survey, NASA commissioned a study for a flyby mission, an orbiter mission, and a lander mission. This paper presents the moon tours for the lander and orbiter concepts. The total delta v and radiation dose would be reduced by exploiting multi-body dynamics and avoiding phasing loops in the Ganymede-to- Europa transfer. Tour 11-O3, 12-L1 and 12-L4 are presented in details and their performaces compared to other tours from previous Europa mission studies.

  20. A multifluid magnetohydrodynamic simulation of the interaction between Jupiter's magnetosphere and its moon Europa

    Science.gov (United States)

    Rubin, M.; Jia, X.; Altwegg, K.; Combi, M. R.; Daldorff, L. K. S.; Gombosi, T. I.; Khurana, K. K.; Kivelson, M.; Tenishev, V.; Toth, G.; van der Holst, B.; Wurz, P.

    2015-12-01

    Jupiter's moon Europa is believed to contain a subsurface water ocean whose finite electrical conductance imposes clear induction signatures on the magnetic field in its surroundings. The evidence rests heavily on measurements performed by the magnetometer on board the Galileo spacecraft during multiple flybys of the moon. Europa's interaction with the Jovian magnetosphere has become a major target of research in planetary science, partly because of the potential of a salty ocean to harbor life outside our own planet. Thus it is of considerable interest to develop numerical simulations of the Europa-Jupiter interaction that can be compared with data in order to refine our knowledge of Europa's subsurface structure. In this presentation we show aspects of Europa's interaction with the Jovian magnetosphere extracted from a multifluid magnetohydrodynamics (MHD) code BATS-R-US recently developed at the University of Michigan. The model dynamically separates magnetospheric and pick-up ions and is capable of capturing some of the physics previously accessible only to kinetic approaches. The model utilizes an adaptive grid to maintain the high spatial resolution on the surface required to resolve the portion of Europa's neutral atmosphere with a scale height of a few tens of kilometers that is in thermal equilibrium. The model also derives the electron temperature, which is crucial to obtain the local electron impact ionization rates and hence the plasma mass loading in Europa's atmosphere. We compare our results with observations made by the plasma particles and fields instruments on the Galileo spacecraft to validate our model. We will show that multifluid MHD is able to reproduce the basic features of the plasma moments and magnetic field observations obtained during the Galileo E4 and E26 flybys at Europa.

  1. Limits to Mercury's magnesium exosphere from MESSENGER second flyby observations

    Science.gov (United States)

    Sarantos, Menelaos; Killen, Rosemary M.; McClintock, William E.; Todd Bradley, E.; Vervack, Ronald J.; Benna, Mehdi; Slavin, James A.

    2011-12-01

    The discovery measurements of Mercury's exospheric magnesium, obtained by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) probe during its second Mercury flyby, are modeled to constrain the source and loss processes for this neutral species. Fits to a Chamberlain exosphere reveal that at least two source temperatures are required to reconcile the distribution of magnesium measured far from and near the planet: a hot ejection process at the equivalent temperature of several tens of thousands of degrees K, and a competing, cooler source at temperatures as low as 400 K. For the energetic component, our models indicate that the column abundance that can be attributed to sputtering under constant southward interplanetary magnetic field conditions is at least a factor of five less than the rate dictated by the measurements. Although highly uncertain, this result suggests that another energetic process, such as the rapid dissociation of exospheric MgO, may be the main source of the distant neutral component. If meteoroid and micrometeoroid impacts eject mainly molecules, the total amount of magnesium at altitudes exceeding ˜100 km is found to be consistent with predictions by impact vaporization models for molecule lifetimes of no more than two minutes. Though a sharp increase in emission observed near the dawn terminator region can be reproduced if a single meteoroid enhanced the impact vapor at equatorial dawn, it is much more likely that observations in this region, which probe heights increasingly near the surface, indicate a reservoir of volatile Mg being acted upon by lower-energy source processes.

  2. Evolution of Jupiter's auroral-related stratospheric heating and chemistry

    Science.gov (United States)

    Sinclair, James; Orton, Glenn S.; Greathouse, Thomas K.; Fletcher, Leigh N.; Moses, Julianne I.; Hue, Vincent; Irwin, Patrick Gerard Joseph; Melin, Henrik; Giles, Rohini Sara

    2016-10-01

    Auroral processes on Jupiter are evident over a large range of wavelengths. Emission at X-ray, UV and near-infrared wavelengths highlights the precipitation of charged particles in Jupiter's ionosphere. Jupiter's auroral regions also exhibit enhanced mid-infrared emission of CH4 (7.8-μm), C2H2 (13-μm), C2H4 (10.5-μm) and C2H6 (12.2-μm), which indicates auroral processes modify the thermal structure and chemistry of the neutral stratosphere at pressures from 10 mbar to 10 μbar. In Sinclair et al., 2016a (submitted), 2016b (in preparation), we investigated these processes further by performing a retrieval analysis of Voyager-IRIS (Infrared Interferometer Spectrometer) observations measured in November 1979, Cassini-CIRS (Composite Infrared Spectrometer) observations measured in January 2001 and IRTF-TEXES (Texas Echelon Cross Echelle Spectrograph on NASA's Infrared Telescope Facility) spectra measured in December 2014. These datasets however captured Jupiter at significantly different epochs and thus the overall global evolution of atmospheric conditions as well as differences in spatial sampling, spectral resolution (and therefore vertical resolution in the atmosphere) have made inferences of the temporal evolution in auroral regions a challenge. However, in April 2016, we acquired IRTF-TEXES observations of Jupiter's high latitudes, using observing parameters very similar to those in December 2014. By performing a similar analysis of these observations and comparing results between December 2014 and April 2016, we can investigate the evolution of the thermal structure and chemistry in Jupiter's auroral regions over a 15 month timescale. The magnitude of temperature/composition changes and the altitudes at which they occur will provide insights into how auroral processes in the ionosphere propagate to the stratosphere. In particular, we can assess whether the evolution of stratospheric conditions in auroral regions is related to the decrease in solar activity

  3. Two Moons Meet over Jupiter

    Science.gov (United States)

    2007-01-01

    This beautiful image of the crescents of volcanic Io and more sedate Europa was snapped by New Horizons' color Multispectral Visual Imaging Camera (MVIC) at 10:34 UT on March 2, 2007, about two days after New Horizons made its closest approach to Jupiter. The picture was one of a handful of the Jupiter system that New Horizons took primarily for their artistic, rather than scientific value. This particular scene was suggested by space enthusiast Richard Hendricks of Austin, Texas, in response to an Internet request by New Horizons scientists for evocative, artistic imaging opportunities at Jupiter. This image was taken from a range of 4.6 million kilometers (2.8 million miles) from Io and 3.8 million kilometers (2.4 million miles) from Europa. Although the moons appear close in this view, a gulf of 790,000 kilometers (490,000 miles) separates them. The night side of Io is illuminated here by light reflected from Jupiter, which is out of the frame to the right. Europa's night side is completely dark, in contrast to Io, because that side of Europa faces away from Jupiter. Here, Io steals the show with its beautiful display of volcanic activity. Three volcanic plumes are visible. Most conspicuous is the enormous 300-kilometer (190-mile) -high plume from the Tvashtar volcano at the 11 o'clock position on Io's disk. Two much smaller plumes are barely visible: one from the volcano Prometheus, at the 9 o'clock position on the edge of Io's disk, and one from the volcano Amirani, seen between Prometheus and Tvashtar along Io's terminator (the line dividing day and night). The plumes appear blue because of the scattering of light by tiny dust particles ejected by the volcanoes, similar to the blue appearance of smoke. In addition, the contrasting red glow of hot lava can be seen at the source of the Tvashtar plume. The images are centered at 1 degree north, 60 degrees west on Io, and 0 degrees north, 149 degrees west on Europa. The color in this image was generated using

  4. The Ultraviolet Spectrograph on the Europa Mission (Europa-UVS)

    Science.gov (United States)

    Retherford, K. D.; Gladstone, R.; Greathouse, T. K.; Steffl, A.; Davis, M. W.; Feldman, P. D.; McGrath, M. A.; Roth, L.; Saur, J.; Spencer, J. R.; Stern, S. A.; Pope, S.; Freeman, M. A.; Persyn, S. C.; Araujo, M. F.; Cortinas, S. C.; Monreal, R. M.; Persson, K. B.; Trantham, B. J.; Versteeg, M. H.; Walther, B. C.

    2015-12-01

    NASA's Europa multi-flyby mission is designed to provide a diversity of measurements suited to enrich our understanding of the potential habitability of this intriguing ocean world. The Europa mission's Ultraviolet Spectrograph, Europa-UVS, is the sixth in a series of successful ultraviolet imaging spectrographs (Rosetta-Alice, New Horizons Pluto-Alice, LRO-LAMP) and, like JUICE-UVS (now under Phase B development), is largely based on the most recent of these to fly, Juno-UVS. Europa-UVS observes photons in the 55-210 nm wavelength range, at moderate spectral and spatial resolution along a 7.5° slit. Three distinct apertures send light to the off-axis telescope mirror feeding the long-slit spectrograph: i) a main entrance airglow port is used for most observations (e.g., airglow, aurora, surface mapping, and stellar occultations); ii) a high-spatial-resolution port consists of a small hole in an additional aperture door, and is used for detailed observations of bright targets; and iii) a separate solar port allows for solar occultations, viewing at a 60° offset from the nominal payload boresight. Photon event time-tagging (pixel list mode) and programmable spectral imaging (histogram mode) allow for observational flexibility and optimal science data management. As on Juno-UVS, the effects of penetrating electron radiation on electronic parts and data quality are mitigated through contiguous shielding, filtering of pulse height amplitudes, management of high-voltage settings, and careful use of radiation-hard parts. The science goals of Europa-UVS are to: 1) Determine the composition & chemistry, source & sinks, and structure & variability of Europa's atmosphere, from equator to pole; 2) Search for and characterize active plumes in terms of global distribution, structure, composition, and variability; 3) Explore the surface composition & microphysics and their relation to endogenic & exogenic processes; and 4) Investigate how energy and mass flow in the Europa

  5. Strong Solar Control of Infrared Aurora on Jupiter: Correlation Since the Last Solar Maximum

    Science.gov (United States)

    Kostiuk, T.; Livengood, T. A.; Hewagama, T.

    2009-01-01

    Polar aurorae in Jupiter's atmosphere radiate throughout the electromagnetic spectrum from X ray through mid-infrared (mid-IR, 5 - 20 micron wavelength). Voyager IRIS data and ground-based spectroscopic measurements of Jupiter's northern mid-IR aurora, acquired since 1982, reveal a correlation between auroral brightness and solar activity that has not been observed in Jovian aurora at other wavelengths. Over nearly three solar cycles, Jupiter auroral ethane emission brightness and solar 10.7 cm radio flux and sunspot number are positively correlated with high confidence. Ethane line emission intensity varies over tenfold between low and high solar activity periods. Detailed measurements have been made using the GSFC HIPWAC spectrometer at the NASA IRTF since the last solar maximum, following the mid-IR emission through the declining phase toward solar minimum. An even more convincing correlation with solar activity is evident in these data. Current analyses of these results will be described, including planned measurements on polar ethane line emission scheduled through the rise of the next solar maximum beginning in 2009, with a steep gradient to a maximum in 2012. This work is relevant to the Juno mission and to the development of the Europa Jupiter System Mission. Results of observations at the Infrared Telescope Facility (IRTF) operated by the University of Hawaii under Cooperative Agreement no. NCC5-538 with the National Aeronautics and Space Administration, Science Mission Directorate, Planetary Astronomy Program. This work was supported by the NASA Planetary Astronomy Program.

  6. Mission interplanetary: Using radioisotope power to explore the solar system

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, Gary L., E-mail: UserSg4282@aol.com

    2008-03-15

    The exploration of space both by humans and robots has been greatly enhanced and, in many cases, enabled by the use of radioisotope power sources (RPSs) to power and/or heat scientific instruments. Radioisotope power sources have enabled such breakthrough missions as the Pioneer flights to Jupiter, Saturn and beyond; the Voyager flights to Jupiter, Saturn, Uranus, Neptune, and beyond; the Apollo lunar surface experiments; the Viking Lander studies of Mars; the Galileo spacecraft that orbited Jupiter; the Ulysses mission to study the polar regions of the Sun; the Cassini spacecraft orbiting Saturn; and the recently launched New Horizons spacecraft to Pluto. Radioisotope heater units have enhanced or enabled the Apollo Early Scientific Experiment Package and the Mars exploration rover missions (Sojourner, Spirit and Opportunity). Since 1961, the United States has successfully flown 41 radioisotope thermoelectric generators (RTGs) to provide electrical power for 23 space missions.

  7. Exploration of Jovian Magnetosphere and Trojan Asteroids by a Solar Power Sail Mission

    Science.gov (United States)

    Sasaki, S.; Fujimoto, M.; Kasaba, Y.; Kawaguchi, J.; Kawakatsu, Y.; Mori, O.; Takashima, T.; Tsuda, Y.; Yano, H.; Jupiter Exploration Working Group

    2009-04-01

    Europa Jupiter System Mission (EJSM) is a proposed international mission to explore Jupiter, Jovian satellites and environment. EJSM consists of (1) The Jupiter Europa Orbiter (JEO) by NASA, (2) the Jupiter Ganymede Orbiter (JGO) by ESA, (3) the Jupiter Magnetospheric Orbiter (JMO) studied by JAXA. (4) The Europa lander is also studied by Roscosmos. Together with plasma instruments on board JEO and JGO, JMO will investigate the fast and huge rotating magnetosphere to clarify the energy procurement from Jovian rotation to the magnetosphere, to clarify the interaction between the solar wind the magnetosphere. JMO will clarify the characteristics of the strongest accelerator in the solar system. JMO will investigate the role of Io as a source of heavy ions in the magnetosphere. Proposed instruments on board JMO are magnetometers, low-energy plasma spectrometers, medium energy particle detectors, energetic particle detectors, electric field / plasma wave instruments, a dust detector, an ENA imager, and EUV spectrometer. JAXA is studying solar power sail for deep space explorations following the successful ion engine mission Hayabusa. This is not only solar sail (photon propulsion) but also include very efficient ion engines where electric power is produced solar panels within the sail. Currently we are studying a mission to Jupiter and one (or two) of Trojan asteroids, which are primitive bodies with information of the early solar system as well as raw solid materials of Jovian system. As the main spacecraft flies by Jupiter heading for an asteroid, it will deploy JMO spinner around Jupiter.

  8. Planetary flybys resulting in heliocentric orbits normal to the ecliptic with fixed perihelia.

    Science.gov (United States)

    Buglia, J. J.

    1973-01-01

    An iterative procedure is applied to a patched conic trajectory sequence in which a spacecraft is launched from the earth, flys by the planet Jupiter, and leaves Jupiter along a heliocentric trajectory whose plane is normal to the ecliptic, and whose perihelion is fixed at 0.1 AU. Six launch opportunities, spaced apart in time at approximately the mean synodic period of earth and Jupiter (roughly 400 days), are examined.

  9. Family Portrait of the Small Inner Satellites of Jupiter

    Science.gov (United States)

    1997-01-01

    These images, taken by Galileo's solid state imaging system between November 1996 and June 1997, provide the first ever 'family portrait' of the four small, irregularly shaped moons that orbit Jupiter in the zone between the planet's ring and the larger Galilean satellites. The moons are shown in their correct relative sizes, with north approximately up in all cases. From left to right, arranged in order of increasing distance from Jupiter, are Metis (longest dimension is approximately 60 kilometers or 37 miles across), Adrastea (20 kilometers or 12 miles across), Amalthea (247 kilometers or 154 miles across), and Thebe (116 kilometers or 72 miles across). While Amalthea, the largest of these four tiny moons, was imaged by NASA's two Voyager spacecraft in 1979 with a resolution comparable to what is shown here, the new Galileo observations represent the first time that Metis, Adrastea, and Thebe have been seen as more than points of light.The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://www.jpl.nasa.gov/ galileo.

  10. An Analysis of Cassini Observations Regarding the Structure of Jupiter's Equatorial Atmosphere

    Science.gov (United States)

    Choi, David S.; Simon-Miller, Amy A.

    2012-01-01

    A variety of intriguing atmospheric phenomena reside on both sides of Jupiter's equator. 5-micron bright hot spots and opaque plumes prominently exhibit dynamic behavior to the north, whereas compact, dark chevron-shaped features and isolated anticyclonic disturbances periodically occupy the southern equatorial latitudes. All of these phenomena are associated with the vertical and meridional perturbations of Rossby waves disturbing the mean atmospheric state. As previous observational analysis and numerical simulations have investigated the dynamics of the region, an examination of the atmosphere's vertical structure though radiative transfer analysis is necessary for improved understanding of this unique environment. Here we present preliminary analysis of a multispectral Cassini imaging data set acquired during the spacecraft's flyby of Jupiter in 2000. We evaluated multiple methane and continuum spectral channels at available viewing angles to improve constraints on the vertical structure of the haze and cloud layers comprising these interesting features. Our preliminary results indicate distinct differences in the structure for both hemispheres. Upper troposphere hazes and cloud layers are prevalent in the northern equatorial latitudes, but are not present in corresponding southern latitudes. Continued analysis will further constrain the precise structure present in these phenomena and the differences between them.

  11. An Analysis of Cassini Observations Regarding the Structure of Jupiter's Equatorial Atmosphere

    Science.gov (United States)

    Choi, David S.; Simon-Miller, Amy A.

    2012-01-01

    A variety of intriguing atmospheric phenomena reside on both sides of Jupiter's equator. 5-micron bright hot spots and opaque plumes prominently exhibit dynamic behavior to the north, whereas compact, dark chevron-shaped features and isolated anticyclonic disturbances periodically occupy the southern equatorial latitudes. All of these phenomena are associated with the vertical and meridional perturbations of Rossby waves disturbing the mean atmospheric state. As previous observational analysis and numerical simulations have investigated the dynamics of the region, an examination of the atmosphere's vertical structure though radiative transfer analysis is necessary for improved understanding of this unique environment. Here we present preliminary analysis of a multispectral Cassini imaging data set acquired during the spacecraft's flyby of Jupiter in 2000. We evaluated multiple methane and continuum spectral channels at available viewing angles to improve constraints on the vertical structure of the haze and cloud layers comprising these interesting features. Our preliminary results indicate distinct differences in the structure for both hemispheres. Upper troposphere hazes and cloud layers are prevalent in the northern equatorial latitudes, but are not present in corresponding southern latitudes. Continued analysis will further constrain the precise structure present in these phenomena and the differences between them.

  12. The Capture of Jupiter Trojans

    Science.gov (United States)

    Morbidelli, A.; Nesvorny, D.; Vokrouhlicky, D.

    2013-09-01

    The origin of Jupiter Trojans remained mysterious for decades. Particularly, it was difficult to explain the excitation of the inclinations of the Trojan population [1]. In 2005, Morbidelli et al. [2] proposed a scenario of capture from the trans-Neptunian disk, in the framework of the so-called "Nice model" [3,4]. This scenario explained in a natural way the observed orbital distribution of Trojans. The Nice model, however, evolved in the years, in order to satisfy an increasingly large number of constraints. It now appears that the dynamical evolution of the giant planets was different from that envisioned in [2]. Here, we assess again the process of capture of Trojans within this new evolution. We show that (6-8)×10 - 7 of the original trans-Neptunian planetesimals are captured in the Trojan region, with an orbital distribution consistent with the one observed. Relative to [2], the new capture mechanism has the potential of explaining the asymmetry between the L4 and L5 populations. Moreover, the resulting population of Trojans is consistent with that of the Irregular Satellites of Jupiter, which are captured in the same process; a few bodies from the main asteroid belt could also be captured in the Trojan cloud.

  13. Longitudinal Variations in Jupiter's Winds

    Science.gov (United States)

    Simon-Miller, Amy A.; Gierasch, P. J.; Tierney, G.

    2010-01-01

    Long-term studies of Jupiter's zonal wind field revealed temporal variations on the order of 20 to 40 m/s at many latitudes, greater than the typical data uncertainties of 1 to 10 m/s. No definitive periodicities were evident, however, though some latitudinally-confined signals did appear at periods relevant to the Quasi- Quadrennial Oscillation (Simon-Miller & Gierasch, Icarus, in press). As the QQO appears, from vertical temperature profiles, to propagate downward, it is unclear why a signal is not more obvious, unless other processes dominate over possibly weaker forcing from the QQO. An additional complication is that zonal wind profiles represent an average over some particular set of longitudes for an image pair and most data sets do not offer global wind coverage. Lien avoiding known features, such as the large anticyclonic vortices especially prevalent in the south, there can be distinct variations in longitude. We present results on the full wind field from Voyager and Cassini data, showing apparent longitudinal variations of up to 60 m/s or more. These are particularly obvious near disruptions such as the South Equatorial Disturbance, even when the feature itself is not clearly visible. These two dates represent very different states of the planet for comparison: Voyagers 1 & 2 flew by Jupiter shortly after a global upheaval, while many regions were in a disturbed state, while the Cassini view is typical of a more quiescent period present during much of the 1990s and early 2000s.

  14. Jupiter's magnetosphere and radiation belts

    Science.gov (United States)

    Kennel, C. F.; Coroniti, F. V.

    1979-01-01

    Radioastronomy and Pioneer data reveal the Jovian magnetosphere as a rotating magnetized source of relativistic particles and radio emission, comparable to astrophysical cosmic ray and radio sources, such as pulsars. According to Pioneer data, the magnetic field in the outer magnetosphere is radially extended into a highly time variable disk-shaped configuration which differs fundamentally from the earth's magnetosphere. The outer disk region, and the energetic particles confined in it, are modulated by Jupiter's 10 hr rotation period. The entire outer magnetosphere appears to change drastically on time scales of a few days to a week. In addition to its known modulation of the Jovian decametric radio bursts, Io was found to absorb some radiation belt particles and to accelerate others, and most importantly, to be a source of neutral atoms, and by inference, a heavy ion plasma which may significantly affect the hydrodynamic flow in the magnetosphere. Another important Pioneer finding is that the Jovian outer magnetosphere generates, or permits to escape, fluxes of relativistic electrons of such intensities that Jupiter may be regarded as the dominant source of 1 to 30 MeV cosmic ray electrons in the heliosphere.

  15. Atmospheric Escape from Hot Jupiters

    CERN Document Server

    Murray-Clay, Ruth; Murray, Norman

    2008-01-01

    Photoionization heating from UV radiation incident on the atmospheres of hot Jupiters may drive planetary mass loss. We construct a model of escape that includes realistic heating and cooling, ionization balance, tidal gravity, and pressure confinement by the host star wind. We show that mass loss takes the form of a hydrodynamic ("Parker") wind, emitted from the planet's dayside during lulls in the stellar wind. When dayside winds are suppressed by the confining action of the stellar wind, nightside winds might pick up if there is sufficient horizontal transport of heat. A hot Jupiter loses mass at maximum rates of ~2 x 10^12 g/s during its host star's pre-main-sequence phase and ~2 x10^10 g/s during the star's main sequence lifetime, for total maximum losses of ~0.06% and ~0.6% of the planet's mass, respectively. For UV fluxes F_UV < 10^4 erg/cm^2/s, the mass loss rate is approximately energy-limited and is proportional to F_UV^0.9. For larger UV fluxes, such as those typical of T Tauri stars, radiative ...

  16. Trajectory Design for the Europa Clipper Mission Concept

    Science.gov (United States)

    Buffington, Brent

    2014-01-01

    Europa is one of the most scientifically intriguing targets in planetary science due to its potential suitability for extant life. As such, NASA has funded the California Institute of Technology Jet Propulsion Laboratory and the Johns Hopkins University Applied Physics Laboratory to jointly determine and develop the best mission concept to explore Europa in the near future. The result of nearly 4 years of work--the Europa Clipper mission concept--is a multiple Europa flyby mission that could efficiently execute a number of high caliber science investigations to meet Europa science priorities specified in the 2011 NRC Decadal Survey, and is capable of providing reconnaissance data to maximize the probability of both a safe landing and access to surface material of high scientific value for a future Europa lander. This paper will focus on the major enabling component for this mission concept--the trajectory. A representative trajectory, referred to as 13F7-A21, would obtain global-regional coverage of Europa via a complex network of 45 flybys over the course of 3.5 years while also mitigating the effects of the harsh Jovian radiation environment. In addition, 5 Ganymede and 9 Callisto flybys would be used to manipulate the trajectory relative to Europa. The tour would reach a maximum Jovicentric inclination of 20.1 deg. have a deterministic (Delta)V of 164 m/s (post periapsis raise maneuver), and a total ionizing dose of 2.8 Mrad (Si).

  17. ISO celebrates its prolonged life with a video of Jupiter

    Science.gov (United States)

    1997-07-01

    This is excellent news for astronomers and especially for the multinational teams, with leaders in France, Germany, the Netherlands and the United Kingdom, who spent many years devising the four instruments served by ISO's telescope. The camera ISOCAM, the photometer ISOPHOT, the Short Wavelength Spectrometer and the Long Wavelength Spectrometer span between them an unprecedented range of infrared wavelengths from 2 to 200 microns. The atmosphere of Jupiter is one of the cool and cloudy places attracting ISO's attention, and ESA today releases a video of unprecedented images of Jupiter. The planet changes its appearance drastically as the camera ISOCAM scans a range of 90 different infrared wavelengths. Picture by picture, ISOCAM picks out different features of the atmosphere's composition and behaviour. These and other results from ISO will enable scientists to sharpen their ideas about how Jupiter's weather works. "ISO is giving us a new impression of the giant planets of the Solar System," comments Roger Bonnet, ESA's director of science. "Not just Jupiter, but Saturn, Uranus and Neptune too. By observing the planets across its very wide range of infrared wavelengths, ISO can see features overlooked even by spacecraft visiting the planets. The remarkable movie of Jupiter released today represents only a few per cent of ISO's wavelength range, yet every image tells its own story." More information about the Jupiter video appears later in this Information Note. How ISO's cold telescope beat the calendar The need to keep ISO's telescope and instruments chilled to a very low temperature sets a limit to their useful operating life. ISO was supplied with more than 2000 litres of superfluid helium to cool it. Slow evaporation maintains key parts of the spacecraft at temperatures close to absolute zero, below minus 271 degrees C. The rate of loss of helium was expected to be about 3 litres a day, but the cryogenic system could not be tested in exactly the conditions

  18. SiGe 130 nm-based Rad-Hard ADC for the JEO Mission Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Ridgetop will demonstrate the feasibility of developing a radiation-hardened analog-to-digital converter (ADC) suitable for the Jupiter Europa Orbiter mission. This...

  19. Flight Path Control Design for the Cassini Solstice Mission

    Science.gov (United States)

    Ballard, Christopher G.; Ionasescu, Rodica

    2011-01-01

    The Cassini spacecraft has been in orbit around Saturn for just over 7 years, with a planned 7-year extension, called the Solstice Mission, which started on September 27, 2010. The Solstice Mission includes 205 maneuvers and 70 flybys which consist of the moons Titan, Enceladus, Dione, and Rhea. This mission is designed to use all available propellant with a statistical margin averaging 0.6 m/s per encounter, and the work done to prove and ensure the viability of this margin is highlighted in this paper.

  20. Mercury's Exosphere During MESSENGER's Second Flyby: Detection of Magnesium and Distinct Distributions of Neutral Species

    Science.gov (United States)

    McClintock, William E.; Vervack, Ronald J., Jr.; Bradley, E. Todd; Killen, Rosemary M.; Mouawad, Nelly; Sprague, Ann L.; Burger, Matthew H.; Solomon, Sean C.; Izenberg, Noam R.

    2009-01-01

    During MESSENGER's second Mercury flyby, the Mercury Atmospheric and Surface Composition Spectrometer observed emission from Mercury's neutral exosphere. These observations include the first detection of emission from magnesium. Differing spatial distributions for sodium, calcium, and magnesium were revealed by observations beginning in Mercury's tail region, approximately 8 Mercury radii anti-sunward of the planet, continuing past the nightside, and ending near the dawn terminator. Analysis of these observations, supplemented by observations during the first Mercury flyby as well as those by other MESSENGER instruments, suggests that the distinct spatial distributions arise from a combination of differences in source, transfer, and loss processes.

  1. NASA's Near Earth Asteroid Scout Mission

    Science.gov (United States)

    Johnson, Les; McNutt, Leslie; Castillo-Rogez, Julie

    2017-01-01

    NASA is developing solar sail propulsion for a near-term Near Earth Asteroid (NEA) reconnaissance mission and laying the groundwork for their future use in deep space science and exploration missions. The NEA Scout mission, funded by NASA's Advanced Exploration Systems Program and managed by NASA MSFC, will use the sail as primary propulsion allowing it to survey and image one or more NEA's of interest for possible future human exploration. NEA Scout uses a 6U cubesat (to be provided by NASA's Jet Propulsion Laboratory), an 86 m2 solar sail and will weigh less than 14 kilograms. The solar sail for NEA Scout will be based on the technology developed and flown by the NASA NanoSail-D and The Planetary Society's Lightsail-A. Four 7 m stainless steel booms wrapped on two spools (two overlapping booms per spool) will be motor deployed and pull the sail from its stowed volume. The sail material is an aluminized polyimide approximately 3 microns thick. NEA Scout will launch on the Space Launch System (SLS) first mission in 2018 and deploy from the SLS after the Orion spacecraft is separated from the SLS upper stage. The NEA Scout spacecraft will stabilize its orientation after ejection using an onboard cold-gas thruster system. The same system provides the vehicle Delta-V sufficient for a lunar flyby. After its first encounter with the moon, the 86 m2 sail will deploy, and the sail characterization phase will begin. A mechanical Active Mass Translation (AMT) system, combined with the remaining ACS propellant, will be used for sail momentum management. Once the system is checked out, the spacecraft will perform a series of lunar flybys until it achieves optimum departure trajectory to the target asteroid. The spacecraft will then begin its two year-long cruise. About one month before the asteroid flyby, NEA Scout will pause to search for the target and start its approach phase using a combination of radio tracking and optical navigation. The solar sail will provide

  2. Strong Langmuir turbulence at Jupiter?

    Science.gov (United States)

    Cairns, Iver H.; Robinson, P. A.

    1992-01-01

    Langmuir wave packets with short scale lengths less than an approximately equal to 100 lambda e have been observed in Jupiter's foreshock. Theoretical constraints on the electric fields and scale sizes of collapsing wave packets are summarized, extended and placed in a form suitable for easy comparison with Voyager and Ulysses data. The published data are reviewed and possible instrumental underestimation of fields discussed. New upper limits for the fields of the published wave packets are estimated. Wave packets formed at the nucleation scale from the observed large-scale fields cannot collapse because they are disrupted before collapse occurs. The published wave packets are quantitatively inconsistent with strong turbulence collapse. Strict constraints exist for more intense wave packets to be able to collapse: E greater than or approximately equals to 1-8 mV/m for scales less than or approximately equal to 100 lambda e. Means for testing these conclusions using Voyager and Ulysses data are suggested.

  3. The Galileo Probe: How it Has Changed Our Understanding of Jupiter

    Science.gov (United States)

    Young, Richard E.

    2003-01-01

    The Galileo Mission to Jupiter, which arrived in December of 1995, provided the first study by an orbiter, and the first in-situ sampling via an entry probe, of an outer planet atmosphere. The rationale for an entry probe is that, even from an orbiter, remote sensing of the jovian atmosphere could not adequately retrieve the information desired. This paper provides a current summary of the most significant aspects of the data returned from the Galileo entry probe. As a result of the probe measurements, there has been a reassessment of our understanding of outer planet formation and evolution of the solar system. The primary scientific objective of the Galileo probe was to determine the composition of the jovian atmosphere, which from remote sensing remained either very uncertain, or completely unknown, with respect to several key elements. The probe found that the global He mass fraction is. significantly above the value reported from the Voyager Jupiter flybys but is slightly below the protosolar value, implying that there has been some settling of He to the deep jovian interior. The probe He measurements have also led to a reevaluation of the Voyager He mass fraction for Saturn, which is now determined to be much closer to that of Jupiter. The elements C, N, S, Ar, Kr, Xe were all found to have global abundances approximately 3 times their respective solar abundances. This result has raised a number of fundamental issues with regard to properties of planetesimals and the solar nebula at the time of giant planet formation. Ne, on the other hand, was found to be highly depleted, probably as the result of it being carried along with helium as helium settles towards the deep interior. The global abundance of O was not obtained by the probe because of the influence of local processes at the probe entry site (PES), processes which depleted condensible species, in this case H2O, well below condensation levels. Other condensible species, namely NH3 and H2S, were

  4. Rosetta-Mars fly-by, February 25, 2007 .

    Science.gov (United States)

    Pajola, M.; Magrin, S.; Lazzarin, M.; La Forgia, F.; Barbieri, C.

    On the 25 of February 2007, the ESA Rosetta mission approached planet Mars. This gravity assist gave the opportunity to the scientific community to get several sets of images through the use of OSIRIS instrument: Rosetta imaging camera. The entire surface of the Red Planet has been imaged as well as the atmosphere and the clouds which were partly covering it. The aim of this paper is to introduce and show the preliminary studies which have concentrated on three images sets obtained during Rosetta closest approach to Mars.

  5. New Views of Jupiter's Rings

    Science.gov (United States)

    Burns, J. A.

    1998-09-01

    Jupiter's rings are the archetype of ethereal planetary rings (very-low optical-depth bands containing micron-sized "dust"). As a result of much improved observations by Galileo (Ockert-Bell* -- most citations are et al. and Icarus in press* or this meeting) and Keck (de Pater*), we now understand the nature of such rings. The ring has three components: a 104 km-thick toroidal halo (1.4-1.7 RJ; normal optical depth t = 10-6), a thin main ring (1.7-1.8 RJ; t = 10-6), and a pair of exterior gossamer rings (1.8-3.5RJ; t = 10-7). The main ring has patchy ( 20-30 percent) brightness. The ring is reddish and its particles satisfy a -2.5 differential power-law size distribution. Because particle lifetimes are brief, the rings must be continually regenerated, by collisions into parent bodies, which may be unseen or may be the known small ring-moons (Thomas*, Simonelli). The gossamer ring seems to be collisional ejecta derived from the ring-moons Amalthea and Thebe, and evolving inward by Poynting-Robertson drag (Burns). The particles drift through many electromagnetic resonances, clustering around synchronous orbit, which produce jumps in the particles' inclinations (Hamilton). The main ring is probably debris from Adrastea and Metis, which orbit in the equatorial plane. The halo particles are driven vertically by electromagnetic forces, which may be resonant (Schaffer & Burns) or not (Horanyi & Cravens). When halo orbits become highly distorted, particles are lost into Jupiter. Similar faint rings may be attendant to all small, close-in satellites (Showalter).

  6. New vision solar system exploration missions study: Analysis of the use of biomodal space nuclear power systems to support outer solar system exploration missions. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-08

    This report presents the results of an analysis of the capability of nuclear bimodal systems to perform outer solar system exploration missions. Missions of interest include orbiter mission s to Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. An initial technology baseline consisting of a NEBA 10 kWe, 1000 N thrust, 850 s, 1500 kg bimodal system was selected, and its performance examined against a data base for trajectories to outer solar system planetary destinations to select optimal direct and gravity assisted trajectories for study. A conceptual design for a common bimodal spacecraft capable of performing missions to all the planetary destinations was developed and made the basis of end to end mission designs for orbiter missions to Jupiter, Saturn, and Neptune. Concepts for microspacecraft capable of probing Jupiter`s atmosphere and exploring Titan were also developed. All mission designs considered use the Atlas 2AS for launch. It is shown that the bimodal nuclear power and propulsion system offers many attractive option for planetary missions, including both conventional planetary missions in which all instruments are carried by a single primary orbiting spacecraft, and unconventional missions in which the primary spacecraft acts as a carrier, relay, and mother ship for a fleet of micro spacecraft deployed at the planetary destination.

  7. Solar composition from the Genesis Discovery Mission.

    Science.gov (United States)

    Burnett, D S; Team, Genesis Science

    2011-11-29

    Science results from the Genesis Mission illustrate the major advantages of sample return missions. (i) Important results not otherwise obtainable except by analysis in terrestrial laboratories: the isotopic compositions of O, N, and noble gases differ in the Sun from other inner solar system objects. The N isotopic composition is the same as that of Jupiter. Genesis has resolved discrepancies in the noble gas data from solar wind implanted in lunar soils. (ii) The most advanced analytical instruments have been applied to Genesis samples, including some developed specifically for the mission. (iii) The N isotope result has been replicated with four different instruments.

  8. JUNO Photovoltaic Power at Jupiter

    Science.gov (United States)

    Dawson, Stephen F.; Stella, Paul; McAlpine, William; Smith, Brian

    2012-01-01

    This paper summarizes the Juno modeling team work on predicting the Juno solar array performance at critical mission points including Juno Orbit Insertion (JOI) and End of Mission (EOM). This report consists of background on Juno solar array design, a summary of power estimates, an explanation of the modeling approach used by Aerospace, a detailed discussion of loss factors and performance predictions, a thermal analysis, and a review of risks to solar array performance

  9. CCD Photometric Observations of 2005 YU55 During the 2011 November Flyby

    Science.gov (United States)

    Warner, B. D.; Stephens, R. D.; Brinsfield, J. W.; Larsen, F. R.; Jacobsen, J.; Foster, J.; Richmond, M.; Franco, L.

    2012-05-01

    Analysis of CCD photometric observations of the near-Earth asteroid 2005 YU55 during the 2011 flyby determined one of two possible periods: 16.3 h or 19.3 h. Initial indications from radar observations are that the longer period is the more probable.

  10. On the effect of ocean tides and tesseral harmonics on spacecraft flybys of the Earth

    CERN Document Server

    Acedo, L

    2016-01-01

    The so-called flyby anomaly has encouraged several authors to analyze in detail the minor perturbative contributions to the trajectory of spacecraft performing a flyby manoeuvre. This anomaly consist of an unexplained increase or decrease of the asymptotic velocity of the spacecraft after a flyby of the Earth in the range of a few mm per second. Some order of magnitude estimations have been performed in recent years to dismiss many possible conventional effects as the source of such an anomaly but no explanation has been found yet. In this paper we perform a study of the perturbation induced by ocean tides in a flybying spacecraft by considering the time dependence of the location of the high tide as the Moon follows its orbit. We show that this effect implies a change of the spacecraft velocity of a few micrometers per second. We also consider the coupling of tesseral harmonics inhomogeneities and the rotation of the Earth and its impact of the spacecraft outgoing velocity. Significant corrections to the obs...

  11. Some effects of topological torsion currents on spacecraft dynamics and the flyby anomaly

    Science.gov (United States)

    Pinheiro, Mario J.

    2016-10-01

    The modified dynamical equation of motions obtained by means of topological torsion currents predicts a so-far unforeseen anomalous acceleration detected in spacecrafts during close planetary flybys in retrograde direction, and a null-effect when spacecrafts approach the planet in the posigrade direction with respect to the planetary sense of rotation.

  12. Solution of the flyby problem for large space debris at sun-synchronous orbits

    Science.gov (United States)

    Baranov, A. A.; Grishko, D. A.; Medvedevskikh, V. V.; Lapshin, V. V.

    2016-05-01

    the paper considers the flyby problem related to large space debris (LSD) objects at low earth orbits. The data on the overall dimensions of known last and upper stages of launch vehicles makes it possible to single out five compact groups of such objects from the NORAD catalog in the 500-2000 km altitude interval. The orbits of objects of each group have approximately the same inclinations. The features of the mutual distribution of the orbital planes of LSD objects in the group are shown in a portrait of the evolution of deviations of the right ascension of ascending nodes (RAAN). In the case of the first three groups (inclinations of 71°, 74°, and 81°), the straight lines of relative RAAN deviations of object orbits barely intersect each other. The fourth (83°) and fifth (97°-100°) LSD groups include a considerable number of objects whose orbits are described by straight lines (diagonals), which intersect other lines many times. The use of diagonals makes it possible to significantly reduce the temporal and total characteristic velocity expenditures required for object flybys, but it complicates determination of the flyby sequence. Diagonal solutions can be obtained using elements of graph theory. A solution to the flyby problem is presented for the case of group 5, formed of LSD objects at sun-synchronous orbits.

  13. On the effect of ocean tides and tesseral harmonics on spacecraft flybys of the Earth

    Science.gov (United States)

    Acedo, L.

    2016-12-01

    The so-called flyby anomaly has encouraged several authors to analyse in detail the minor perturbative contributions to the trajectory of spacecraft performing a flyby manoeuvre. This anomaly consist of an unexplained increase or decrease of the asymptotic velocity of the spacecraft after a flyby of the Earth in the range of a few mm per second. Some order of magnitude estimations have been performed in recent years to dismiss many possible conventional effects as the source of such an anomaly but no explanation has been found yet. In this paper we perform a study of the perturbation induced by ocean tides in a flybying spacecraft by considering the time dependence of the location of the high tide as the Moon follows its orbit. We show that this effect implies a change of the spacecraft velocity of a few micrometres per second. We also consider the coupling of tesseral harmonics inhomogeneities and the rotation of the Earth and its impact on the spacecraft outgoing velocity. Significant corrections to the observed asymptotic velocities are found in this case but neither their sign nor their magnitude coincide with the anomalies. So, we can also rule this out as a conventional explanation.

  14. Effects of stellar flybys on planetary systems: 3D modeling of the circumstellar disk's damping effects

    Science.gov (United States)

    Picogna, G.; Marzari, F.

    2014-04-01

    Context. Stellar flybys in star clusters are suspected of affecting the orbital architecture of planetary systems causing eccentricity excitation and orbital misalignment between the planet orbit and the equatorial plane of the star. Aims: We explore whether the impulsive changes in the orbital elements of planets, caused by a hyperbolic stellar flyby, can be fully damped by the circumstellar disk surrounding the star. The time required to disperse stellar clusters is comparable to the circumstellar disk's lifetime. Since we perform 3D simulations, we can also test the inclination, excitation, and damping. Methods: We have modeled in 3D with the SPH code VINE, a system made of a solar-type star surrounded by a low density disk with a giant planet embedded in it approached on a hyperbolic encounter trajectory by a second star of similar mass and with its own disk. Different inclinations between the disks, planet orbit, and star trajectory have been considered to explore various encounter geometries. We focus on an extreme configuration where a very deep stellar flyby perturbs a Jovian planet on an external orbit. This allows us to test in full the ability of the disk to erase the effects of the stellar encounter. Results: We find that the amount of mass lost by the disk during the stellar flyby is less than in 2D models where a single disk was considered. This is mostly related to the mass exchange between the two disks at the encounter. The damping in eccentricity is slightly faster than in 2D models and it occurs on timescales on the order of a few kyr. During the flyby both the disks are warped owing to the mutual interaction and to the stellar gravitational perturbations, but they quickly relax to a new orbital plane. The planet is quickly dragged back within the disk by the tidal interaction with the gas. The only trace of the flyby left in the planet system, after about 104 yr, is a small misalignment, lower than 9°, between the star equatorial plane and the

  15. Scaling the V& V mountain: Proving Juno will succeed at Jupiter

    Science.gov (United States)

    Rocca, J.; Lord, N.; Johnson, M.; Bone, B.

    Juno is a NASA New Frontiers mission managed and operated by the NASA Jet Propulsion Laboratory (JPL), commissioned to explore the origin, interior, atmosphere, and polar magnetosphere of Jupiter. The spacecraft was developed and built by Lockheed Martin Space Systems, and its nine science instruments were developed by JPL and six national and international partner institutions. Juno launched on August 5th, 2011 starting its 5 year cruise to Jupiter and will enter an ~11 day polar orbit that will allow for science measurements while minimizing radiation. Juno is a spin-stabilized, solar-powered spacecraft with a challenging and complex mission, which included over 7,500 requirements and 900 verification activities to be completed during the integration and test campaign.

  16. Jupiter's Role in Sculpting the Early Solar System

    Science.gov (United States)

    Naoz, Smadar

    2015-03-01

    Recent observations made by the Kepler space mission, combined with statistical analysis of existing ground and space-based data, have shown that planets somewhat bigger than the Earth - but substantially smaller than Jupiter - ;are extremely common in our Galaxy (1-4). These systems are typically found to be tightly packed, nearly coplanar, and have nearly circular orbits. Furthermore, these planets tend to have very short-period orbits, ranging from days to months. In contrast, our innermost planet, Mercury, orbits the Sun once every 88 d. Thus, taken at face value, these observations imply that the architecture of our Solar System is unique compared with the galactic population. In other words, why are there no short-period planets in our Solar System? In PNAS, Batygin and Laughlin (5) demonstrate that Jupiter is to blame. In particular, Jupiter's inward-followed-by-outward migration during the Solar System's early evolution could have driven a collisional cascade that would grind planetesimals to smaller size. Gas drag, which dominates these small planetesimals, may then have driven preexisting short-period planets into the Sun. Thus, Batygin and Laughlin (5) suggest that the terrestrial planets in our Solar System are in fact "second-generation planets," which formed after the first short-period planets were destroyed, in mass-dispersed, gas-depleted conditions (see Fig. 1 for the description of the scenario). The developed model suggests that systems with short-period Earth and super-Earth planets are anticorrelated with the existence of giant planets within the same system.

  17. Astronomers find distant planet like Jupiter

    CERN Multimedia

    2003-01-01

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

  18. Kepler constraints on planets near hot Jupiters

    Energy Technology Data Exchange (ETDEWEB)

    Steffen, Jason H.; /Fermilab; Ragozzine, Darin; /Harvard-Smithsonian Ctr. Astrophys.; Fabrycky, Daniel C.; /UC, Santa Cruz, Astron. Astrophys.; Carter, Joshua A.; /Harvard-Smithsonian Ctr. Astrophys.; Ford, Eric B.; /Florida U.; Holman, Matthew J.; /Harvard-Smithsonian Ctr. Astrophys.; Rowe, Jason F.; /NASA, Ames; Welsh, William F.; /San Diego State U., Astron. Dept.; Borucki, William J.; /NASA, Ames; Boss, Alan P.; /Carnegie Inst., Wash., D.C., DTM; Ciardi, David R.; /Caltech /Harvard-Smithsonian Ctr. Astrophys.

    2012-05-01

    We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 2:1 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly two-thirds to five times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history.

  19. Analysis of JUPITER experiment in ZPPR-9

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-09-15

    Information and data from the ZPPR-9 reactor JUPITER experiment are presented concerning a general description of data and methods; criticality; reaction rate ratio and reaction rate distribution; Doppler and sample reactivity worth; sodium void worth; and control rod worth.

  20. Kepler constraints on planets near hot Jupiters

    CERN Document Server

    Steffen, Jason H; Fabrycky, Daniel C; Carter, Joshua A; Ford, Eric B; Holman, Matthew J; Rowe, Jason F; Welsh, William F; Borucki, William J; Boss, Alan P; Ciardi, David R; Quinn, Samuel N

    2012-01-01

    We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 days) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 2:1 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly 2/3 to 5 times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations or TTVs) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history.

  1. Far infrared spectrophotometry of Jupiter and Saturn

    Science.gov (United States)

    Erickson, E. F.; Goorvitch, D.; Simpson, J. P.; Strecker, D. W.

    1978-01-01

    Infrared spectral measurements of Mars, Jupiter, and Saturn were obtained from 100 to 470 kaysers and, by taking Mars as a calibration source, brightness temperatures of Jupiter and Saturn were determined with approximately 5 kayser resolution. Internal luminosities were determined from the data and are reported to be approximately 8 times 10 to the minus tenth power of the sun's luminosity for Jupiter and approximately 3.6 times 10 to the minus tenth power of the sun's luminosity for Saturn. Comparison of data with spectra predicted by models suggests the need for an opacity source in addition to gaseous hydrogen and ammonia to help explain Jupiter's observed spectrum in the vicinity of 250 kaysers.

  2. Jupiter Great Red Spot and White Ovals

    Science.gov (United States)

    1979-01-01

    This photo of Jupiter was taken by Voyager 1 on March 1, 1979. The spacecraft was 3 million miles (5 million kilometers) from Jupiter at the time. The photo shows Jupiter's Great Red Spot (upper right) and the turbulent region immediately to the west. At the middle right of the frame is one of several white ovals seen on Jupiter from Earth. The structure in every feature here is far better than has ever been seen from any telescopic observations. The Red Spot and the white oval both reveal intricate and involved structure. The smallest details that can be seen in this photo are about 55 miles (95 kilometers) across. JPL manages and controls the Voyager project for NASA's Office of Space Science.

  3. Tidal Response of Preliminary Jupiter Model

    CERN Document Server

    Wahl, Sean M; Militzer, Burkhard

    2016-01-01

    In anticipation of improved observational data for Jupiter's gravitational field from the Juno spacecraft, we predict the static tidal response for a variety of Jupiter interior models based on ab initio computer simulations of hydrogen-helium mixtures. We calculate hydrostatic-equilibrium gravity terms using the non-perturbative concentric Maclaurin Spheroid (CMS) method that eliminates lengthy expansions used in the theory of figures. Our method captures terms arising from the coupled tidal and rotational perturbations, which we find to be important for a rapidly-rotating planet like Jupiter. Our predicted static tidal Love number $k_2 = 0.5900$ is $\\sim$10\\% larger than previous estimates. The value is, as expected, highly correlated with the zonal harmonic coefficient $J_2$, and is thus nearly constant when plausible changes are made to interior structure while holding $J_2$ fixed at the observed value. We note that the predicted static $k_2$ might change due to Jupiter's dynamical response to the Galilea...

  4. Kepler constraints on planets near hot Jupiters.

    Science.gov (United States)

    Steffen, Jason H; Ragozzine, Darin; Fabrycky, Daniel C; Carter, Joshua A; Ford, Eric B; Holman, Matthew J; Rowe, Jason F; Welsh, William F; Borucki, William J; Boss, Alan P; Ciardi, David R; Quinn, Samuel N

    2012-05-22

    We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 21 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly two-thirds to five times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history.

  5. OSS (Outer Solar System): A fundamental and planetary physics mission to Neptune, Triton and the Kuiper Belt

    OpenAIRE

    Christophe, Bruno; Spilker, Linda J.; Anderson, John D.; André, Nicolas; Asmar, Sami W.; Aurnou, Jonathan; Banfield, Don; Barucci, Antonella; Bertolami, Orfeu; Bingham, Robert; Brown, Patrick; Cecconi, Baptiste; Courty, Jean-Michel; Dittus, Hansjörg; Fletcher, Leigh N.

    2011-01-01

    The present OSS mission continues a long and bright tradition by associating the communities of fundamental physics and planetary sciences in a single mission with ambitious goals in both domains. OSS is an M-class mission to explore the Neptune system almost half a century after flyby of the Voyager 2 spacecraft. Several discoveries were made by Voyager 2, including the Great Dark Spot (which has now disappeared) and Triton's geysers. Voyager 2 revealed the dynamics of Neptune's atmosphere a...

  6. Observing Campaign for Potential Deep Impact Flyby Target 163249 (2002 GT)

    Science.gov (United States)

    Pittichova, Jana; Chesley, S. R.; Abell, P. A.; Benner, L. A. M.

    2012-01-01

    The Deep Impact spacecraft is currently on course for a Jan. 4, 2020 flyby of the sub-kilometer near-Earth asteroid 163249 (2002 GT). The re-targeting will be complete with a final small maneuver scheduled for Oct. 4, 2012. 2002 GT, which is also designated as a Potentially Hazardous Asteroid (PHA), has a well-determined orbit and is approx 800 m in diameter (H=18.3). Little more is known about the nature of this object, but in mid-2013 it will pass near the Earth, affording an exceptional opportunity for ground-based characterization. At this apparition 2002 GT will be in range of Arecibo. In addition to Doppler measurements, radar delay observations with precisions of a few microseconds are expected and have a good chance of revealing whether the system is binary or not. The asteroid will be brighter than 16th mag., which will facilitate a host of observations at a variety of wavelengths. Light curve measurements across a wide range of viewing perspectives will reveal the rotation rate and ultimately lead to strong constraints on the shape and pole orientation. Visible and infrared spectra will constrain the mineralogy, taxonomy, albedo and size. Along with the radar observations, optical astrometry will further constrain the orbit, both to facilitate terminal guidance operations and to potentially reveal nongravitational forces acting on the asteroid. Coordinating all of these observations will be a significant task and we encourage interested observers to collaborate in this effort. The 2013 apparition of 2002 GT represents a unique opportunity to characterize a potential flyby target, which will aid interpretation of the high-resolution flyby imagery and aid planning and development of the flyby imaging sequence. The knowledge gained from this flyby will be highly relevant to the human exploration program at NASA, which desires more information on the physical characteristics of sub-kilometer near-Earth asteroids.

  7. Jupiter Icy Moons Orbiter (JIMO) Electrical Systems Testbed

    Science.gov (United States)

    Trapp, Scott J.

    2004-01-01

    The Jupiter Icy Moons Orbiter (JIMO) mission will send a spacecraft to explore three of Jupiter s moons (Callisto, Ganymede, and Europa), all of which show evidence of containing vast subterranean oceans beneath their icy surfaces. The evidence of these oceans was discovered by Galileo, and the moons are believed to have the three essential ingredients for life: water, energy, and the necessary chemical elements. Galileo has shown that melted water on Europa has been in contact with the surface of the moon in geologically recent times, and may still lie relatively close to the surface. This project will also introduce a revolutionary new form of electric propulsion powered by a nuclear fission reactor. This electric propulsion is called ion propulsion. It was used on a previous mission called Deep Space 1, proving that ion propulsion works for interplanetary travel. Since JIMO will be traveling farther from the sun, solar power will be difficult to supply the electric energy demanded by the mission. Therefore a nuclear reactor and a thermo-electric converter system will be necessary. Besides making the trip to three of Jupiter's moons - one after the other - a realistic possibility, this new form of power and propulsion opens up the rest of the outer solar system for future exploration. JIMO will fulfill its goals by exploring Europa first, with subsequent trips to the moons Callisto and Ganymede in order to provide comparisons key to understanding the evolution of all three. In order to ensure the stability and proper preparation of the electrical system on JIMO, the High Power AC Power Management and Distribution (PMAD) Test Bed is being developed. The testing on.this AC PMAD will consist of electrical performance verification of candidate power system components. Examples of these components are: high power AC switchgear, high power ACDC converters, AC power distribution units, DC power distribution units, etc. Throughout the course of the summer the over

  8. Voyager-Jupiter radio science data papers

    Science.gov (United States)

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

    1980-01-01

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

  9. Jupiter's Radiation Belts: Can Pioneer 10 Survive?

    Science.gov (United States)

    Hess, W N; Birmingham, T J; Mead, G D

    1973-12-07

    Model calculations of Jupiter's electron and proton radiation belts indicate that the Galilean satellites can reduce particle fluxes in certain regions of the inner magnetosphere by as much as six orders of magnitude. Average fluxes should be reduced by a factor of 100 or more along the Pioneer 10 trajectory through the heart of Jupiter's radiation belts in early December. This may be enough to prevent serious radiation damage to the spacecraft.

  10. Tidal Response of Preliminary Jupiter Model

    OpenAIRE

    Wahl, Sean M; Hubbard, Willam B.; Militzer, Burkhard

    2016-01-01

    In anticipation of improved observational data for Jupiter's gravitational field from the Juno spacecraft, we predict the static tidal response for a variety of Jupiter interior models based on ab initio computer simulations of hydrogen-helium mixtures. We calculate hydrostatic-equilibrium gravity terms using the non-perturbative concentric Maclaurin Spheroid (CMS) method that eliminates lengthy expansions used in the theory of figures. Our method captures terms arising from the coupled tidal...

  11. The Goldstone Apple Valley Radio Telescope (GAVRT) Jupiter Radio Data: Online Access and Analysis Tools

    Science.gov (United States)

    Arballo, J. K.; Levin, S.; Dorcey, R.; Hofstadter, M. D.; Leflang, J.; Jauncey, D.

    2016-12-01

    K-12 students have been collecting GHz radio data on Jupiter with a 34-meter dish in support of the Juno mission. These observations are part of the Goldstone Apple Valley Radio Telescope (GAVRT) project and the raw data are now freely available online. In this poster we describe the newly developed data access and analysis tools which allow both students and professional astronomers to access and analyze the data.

  12. An Exo-Jupiter Candidate in the Eclipsing Binary FL Lyr

    CERN Document Server

    Kozyreva, V S; Demkov, B P; Zotov, L V; Tutukov, A V

    2015-01-01

    Light curves of the eclipsing binary FL Lyr acquired by the Kepler space telescope are analyzed. Eclipse timing measurements for FL Lyr testify to the presence of a third body in the system. Preliminary estimates of its mass and orbital period are > 2M_Jupiter and > 7 yrs. The times of primary minimum in the light curve of FL Lyr during the operation of the Kepler mission are presented.

  13. Tracking Jupiter's Quasi-Quadrennial Oscillation and Mid-Latitude Zonal Waves with High Spectral Resolution Mid-Infrared Observations

    Science.gov (United States)

    Greathouse, Thomas K.; Orton, Glenn S.; Cosentino, Rick; Morales-Juberias, Raul; Fletcher, Leigh N.; Giles, Rohini Sara; Melin, Henrik; Encrenaz, Therese A.; Fouchet, Thierry; DeWitt, Curtis N.

    2016-10-01

    We report on early results of a long term observational study to track the temporal and 3-dimensional evolution of the Quasi-Quadrennial Oscillation (QQO) and the propagation and evolution of mid-latitude zonal waves in Jupiter's stratosphere. These wave-driven phenomena affect variations in Jupiter's vertical and horizontal temperature field, which can be inferred by measuring methane emission in the thermal infrared near 1245 cm-1. Using TEXES, the Texas Echelon cross-dispersed Echelle Spectrograph, mounted on the NASA Infrared Telescope Facility (IRTF) we observed high-spectral resolution (R=75,000) scan maps of Jupiter's equator to mid-latitudes from January 2012 through to the present. We will present the zonally averaged inferred thermal structure within ±30° latitude of the equator and between 10 and 0.01 mbar, showing the QQO's downward progression along with inferred 3-dimensional thermal maps (latitude, longitude, pressure) displaying a multitude of independent waves and eddies at various latitudes and pressures. These results reveal a vast array of wave activity on Jupiter and will serve to: 1) significantly improve the determination of the period and vertical descent velocity of Jupiter's QQO; 2) measure the zonal wavenumbers, vertical wavelengths, zonal group velocities and lifetimes of transient mid-latitude waves; and 3) record the thermal state of Jupiter's stratosphere in detail prior to, during, and after Juno's prime mission.

  14. VIMS spectral mapping observations of Titan during the Cassini prime mission

    Science.gov (United States)

    Barnes, J.W.; Soderblom, J.M.; Brown, R.H.; Buratti, B.J.; Sotin, Christophe; Baines, K.H.; Clark, R.N.; Jaumann, R.; McCord, T.B.; Nelson, R.; Le, Mouelic S.; Rodriguez, S.; Griffith, C.; Penteado, P.; Tosi, F.; Pitman, K.M.; Soderblom, L.; Stephan, K.; Hayne, P.; Vixie, G.; Bibring, J.-P.; Bellucci, G.; Capaccioni, F.; Cerroni, P.; Coradini, A.; Cruikshank, D.P.; Drossart, P.; Formisano, V.; Langevin, Y.; Matson, D.L.; Nicholson, P.D.; Sicardy, B.

    2009-01-01

    This is a data paper designed to facilitate the use of and comparisons to Cassini/visual and infrared mapping spectrometer (VIMS) spectral mapping data of Saturn's moon Titan. We present thumbnail orthographic projections of flyby mosaics from each Titan encounter during the Cassini prime mission, 2004 July 1 through 2008 June 30. For each flyby we also describe the encounter geometry, and we discuss the studies that have previously been published using the VIMS dataset. The resulting compliation of metadata provides a complementary big-picture overview of the VIMS data in the public archive, and should be a useful reference for future Titan studies. ?? 2009 Elsevier Ltd.

  15. A study of Jupiter's aurorae with XMM-Newton

    CERN Document Server

    Branduardi-Raymont, G; Elsner, R F; Gladstone, G R; Ramsay, G; Rodríguez, P; Soria, R; Cravens, T E

    2006-01-01

    We present a detailed analysis of Jupiter's X-ray (0.2-10 keV) auroral emissions as observed by XMM-Newton in Nov. 2003 and compare it with that of an Apr. 2003 observation. We discover the existence of an electron bremsstrahlung component in the aurorae, which accounts for essentially all the X-ray flux above 2 keV: its presence had been predicted but never detected for lack of sensitivity of previous X-ray missions. This bremsstrahlung component varied significantly in strength and spectral shape over the 3.5 days covered by the Nov. 2003 observation, displaying substantial hardening of the spectrum with increasing flux. This variability may be linked to the strong solar activity taking place at the time, and may be induced by changes in the acceleration mechanisms inside Jupiter's magnetosphere. As in Apr. 2003, the auroral spectra below 2 keV are best fitted by a superposition of line emission most likely originating from ion charge exchange, with OVII playing the dominant role. We still cannot resolve co...

  16. Confirmation of Two Hot Jupiters from K2 Campaign 4

    CERN Document Server

    Johnson, Marshall C; Fridlund, Malcolm; Csizmadia, Szilard; Endl, Michael; Cabrera, Juan; Cochran, William D; Deeg, Hans J; Grziwa, Sascha; Ramírez, Ivan; Hatzes, Artie P; Eigmüller, Philipp; Barragán, Oscar; Erikson, Anders; Guenther, Eike W; Korth, Judith; Kuutma, Teet; Nespral, David; Pätzold, Martin; Palle, Enric; Prieto-Arranz, Jorge; Rauer, Heike; Saario, Joonas

    2016-01-01

    We confirm the planetary nature of two transiting hot Jupiters discovered by the Kepler spacecraft's K2 extended mission in its Campaign 4, using precise radial velocity measurements from FIES@NOT, HARPS-N@TNG, and the coud\\'e spectrograph on the McDonald Observatory 2.7 m telescope. EPIC 211089792 b transits a K1V star with a period of $3.2589263\\pm0.0000015$ days; its orbit is slightly eccentric ($e=0.086_{-0.025}^{+0.035}$). It has a radius of $R_P=0.998_{-0.066}^{+0.072}$ $R_J$ and a mass of $M_P=0.613_{-0.027}^{+0.028}$ $M_J$. Its host star exhibits significant rotational variability, and we measure a rotation period of $P_{\\mathrm{rot}}=10.777 \\pm 0.031$ days. EPIC 210957318 b transits a G6V star with a period of $4.098503\\pm0.000011$ days. It has a radius of $R_P=1.039_{-0.051}^{+0.050}$ $R_J$ and a mass of $M_P=0.579_{-0.027}^{+0.028}$ $M_J$. The star has a low metallicity for a hot Jupiter host, $[\\mathrm{Fe}/\\mathrm{H}]=-0.15 \\pm 0.05$.

  17. The crucial role of HST during the NASA Juno mission: a "Juno initiative"

    CERN Document Server

    Grodent, Denis; Gérard, Jean-Claude; Gladstone, G Randall; Nichols, Jonathan D; Clarke, John T; Bagenal, Fran; Adriani, Alberto

    2015-01-01

    In 2016, the NASA Juno spacecraft will initiate its one-year mission around Jupiter and become the first probe to explore the polar regions of Jupiter. The HST UV instruments (STIS and ACS) can greatly contribute to the success of the Juno mission by providing key complementary views of Jupiter's UV aurora from Earth orbit. Juno carries an ultraviolet Spectrograph (UVS) and an infrared spectral mapper (JIRAM) that will obtain high-resolution spectral images providing the auroral counterpart to Juno's in situ particles and fields measurements with the plasma JADE and JEDI particle detectors. The Juno mission will be the first opportunity to measure simultaneously the energetic particles at high latitude and the auroral emissions they produce. Following programmatic and technical limitations, the amount of UVS data transmitted to Earth will be severely restricted. Therefore, it is of extreme importance that HST captures as much additional information as possible on Jupiter's UV aurora during the one-year life o...

  18. An integrated model for Jupiter's dynamo action and mean jet dynamics

    Science.gov (United States)

    Gastine, Thomas; Wicht, Johannes; Duarte, Lucia; Heimpel, Moritz

    2014-05-01

    Data from various space crafts revealed that Jupiter's large scale interior magnetic field is very Earth-like. This is surprising since numerical simulations have demonstrated that, for example, the radial dependence of density, electrical conductivity and other physical properties, which is only mild in the iron cores of terrestrial planets but very drastic in gas planets, can significantly affect the interior dynamics. Jupiter's dynamo action is thought to take place in the deeper envelope where hydrogen, the main constituent of Jupiter's atmosphere, assumes metallic properties. The potential interaction between the observed zonal jets and the deeper dynamo region is an unresolved problem with important consequences for the magnetic field generation. Here we present the first numerical simulation that is based on recent interior models and covers 99% of the planetary radius (below the 1 bar level). A steep decease in the electrical conductivity over the outer 10% in radius allowed us to model both the deeper metallic region and the outer molecular layer in an integrated approach. The magnetic field very closely reproduces Jupiter's known large scale field. A strong equatorial zonal jet remains constrained to the molecular layer while higher latitude jets are suppressed by Lorentz forces. This suggests that Jupiter's higher latitude jets remain shallow and are driven by an additional effect not captured in our deep convection model. The dynamo action of the equatorial jet produces a band of magnetic field located around the equator. The unprecedented magnetic field resolution expected from the Juno mission will allow to resolve this feature allowing a direct detection of the equatorial jet dynamics at depth. Typical secular variation times scales amount to around 750 yr for the dipole contribution but decrease to about 5 yr at the expected Juno resolution (spherical harmonic degree 20). At a nominal mission duration of one year Juno should therefore be able to

  19. Current Status of the Jupiter Europa Orbiter (JEO): Science & Science Implementation

    Science.gov (United States)

    Pappalardo, Robert T.; Blanc, M.; Clark, K.; Greeley, R.; Hendrix, A.; Lebreton, J.; Prockter, L.; Joint Jupiter Science Definition Team

    2008-09-01

    The Jupiter-Europa Orbiter (JEO) is one component of the proposed multi-spacecraft Europa Jupiter System Mission (EJSM). The overarching goal of JEO is to explore Europa to investigate its habitability. Europa is believed to shelter an ocean between its geodynamically active icy shell and its rocky mantle, where the conditions for habitability may be fulfilled. With a warm, salty, water ocean and plausible chemical energy sources, Europa is the astrobiological archetype for icy satellite habitability. It is also a geophysical wonderland of interrelated ice shell processes that are intimately related to the ocean and tides, and of complex interactions among its interior, surface, atmosphere, and magnetospheric environments. A mission to Europa has been studied for a decade and has strong links to and recommendations from NASA reports. The conditions at Europa are well-understood, and JEO is prepared for the radiation environment at Europa. Europa science is mature, and hypotheses are well-formed. Five broad investigations have been defined to address the overarching goal: the Ocean, the Ice Shell, Chemistry, Geology and the Jupiter System. Measuring Europa's tides provides a simple and definitive test of the existence of an internal ocean - and the ocean and ice shell can be studied and characterized. Composition and chemistry form the linkages that enable understanding Europa's potential for life and habitability in the context of geologic processes, probe the interior structure, and record the evolution of the surface under the influence of internal and external processes. The search for recent or current geologic activity is important for understanding the origin of landforms, and especially significant for understanding Europa's potential for habitability. Understanding the Jupiter system as a whole is critical for placing Europa in its context as a member of the Jovian satellite system and for understanding the origin and evolution of the system, including

  20. Current Status of the Jupiter Europa Orbiter (JEO): Science and Science Implementation

    Science.gov (United States)

    Pappalardo, R. T.; Blanc, M.; Clark, K.; Greeley, R.; Hendrix, A. R.; Lebreton, J.; Prockter, L.; JEO Definition Team

    2008-12-01

    The Jupiter-Europa Orbiter (JEO) is one component of the proposed multi-spacecraft Europa Jupiter System Mission (EJSM). The overarching goal of JEO is to explore Europa to investigate its habitability. Europa is believed to shelter an ocean between its geodynamically active icy shell and its rocky mantle, where the conditions for habitability may be fulfilled. With a warm, salty, water ocean and plausible chemical energy sources, Europa is the astrobiological archetype for icy satellite habitability. It is also a geophysical wonderland of interrelated ice shell processes that are intimately related to the ocean and tides, and of complex interactions among its interior, surface, atmosphere, and magnetospheric environments. A mission to Europa has been studied for a decade and has strong links to and recommendations from NASA reports. The conditions at Europa are well-understood, and JEO is prepared for the radiation environment at Europa. Europa science is mature, and hypotheses are well-formed. Five broad investigations have been defined to address the overarching goal: the Ocean, the Ice Shell, Chemistry, Geology and the Jupiter System. Measuring Europa's tides provides a simple and definitive test of the existence of an internal ocean - and the ocean and ice shell can be studied and characterized. Composition and chemistry form the linkages that enable understanding Europa's potential for life and habitability in the context of geologic processes, probe the interior structure, and record the evolution of the surface under the influence of internal and external processes. The search for recent or current geologic activity is important for understanding the origin of landforms, and especially significant for understanding Europa's potential for habitability. Understanding the Jupiter system as a whole is critical for placing Europa in its context as a member of the Jovian satellite system and for understanding the origin and evolution of the system, including

  1. Imaging Jupiter Radiation Belts At Low Frequencies

    Science.gov (United States)

    Girard, J. N.; de Pater, I.; Zarka, P.; Santos-Costa, D.; Sault, R.; Hess, S.; Cecconi, B.; Fender, R.; Pewg, Lofar

    2014-04-01

    , at different epochs only provided, each time, glimpses of the spectral content in different observational configurations. As the synchrotron emission frequency peaks at Vmax / E2B (with Vmax in MHz, E, the electron energy in MeV and B, the magnetic field in Gauss), the low frequency content of this emission is associated with low energy electron populations inside the inner belt and the energetic electrons located in regions of weaker magnetic field (at few jovian radii). Therefore, there is much interest in extending and completing the current knowledge of the synchrotron emission from the belts, with low frequency resolved observations. LOFAR, the LOw Frequency ARray (LOFAR) [6], is a giant flexible and digital ground-based radio interferometer operating in the 30-250 MHz band. It brings very high time (~ μs), frequency (~ kHz) and angular resolutions (~1") and huge sensitivity (mJy). In November 2011, a single 10-hour track enabled to cover an entire planetary rotation and led to the first resolved image of the radiation belts between 127- 172 MHz [7,8]. In Feb 2013, an 2×5h30 joint LOFAR/ WSRT observing campaign seized the state of the radiation belts from 45 MHz up to 5 GHz. We will present the current state of the study (imaging, reconstruction method and modeling) of the radiation belts dynamic with this current set of observations. LOFAR can contribute to the understanding of the physics taking place in the inner belt as well as possibly providing a fast and a systematic "diagnostic" of the state of the belts. The latter represents an opportunity to give context and ground-based support for the arrival of JUNO (NASA) scheduled in July 2016 and also for future missions, such as JUICE (ESA), at the vicinity of Jupiter by the exploration of its icy satellites.

  2. Using Jupiter's Synchrotron Radiation as a Probe into Jupiter's Inner Radiation Belts

    Science.gov (United States)

    Bolton, S. J.; Gulkis, S.; Klein, M. J.; Thorne, R. M.

    1995-01-01

    The Jovian decimetric emission is caused by the combined emission of synchrotron radiation originating from the relativistic electrons trapped in Jupiter's 'Van Allen radiation belts' and thermal emission from the planet's atmosphere. Synchrotron radiation characteristics and variations (which provides insight into the physical properties of Jupiter's inner radiation belts) will be amplified and discussed.

  3. Temporal Variations in Jupiter's Atmosphere

    Science.gov (United States)

    Simon-Miller, Amy A.; Chanover, N. J.; Yanamandra-Fisher, P.; Hammel, H. B.; dePater, I.; Noll, K.; Wong, M.; Clarke, J.; Sanchez-Levega, A.; Orton, G. S.; Gonzaga, S.

    2009-01-01

    In recent years, Jupiter has undergone many atmospheric changes from storms turning red to global. cloud upheavals, and most recently, a cornet or asteroid impact. Yet, on top of these seemingly random changes events there are also periodic phenomena, analogous to observed Earth and Saturn atmospheric oscillations. We will present 15 years of Hubble data, from 1994 to 2009, to show how the equatorial tropospheric cloud deck and winds have varied over that time, focusing on the F953N, F41 ON and F255W filters. These filters give leverage on wind speeds plus cloud opacity, cloud height and tropospheric haze thickness, and stratospheric haze, respectively. The wind data consistently show a periodic oscillation near 7-8 S latitude. We will discuss the potential for variations with longitude and cloud height, within the calibration limits of those filters. Finally, we will discuss the role that large atmospheric events, such as the impacts in 1994 and 2009, and the global upheaval of 2007, have on temporal studies, This work was supported by a grant from the NASA Planetary Atmospheres Program. HST observational support was provided by NASA through grants from Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under contract NAS5-26555.

  4. The possible contamination of Jupiter

    Science.gov (United States)

    Garcia, Joe

    1988-01-01

    The Galileo probe, though at present its future is uncertain, would, if not sterilized, represent a good chance of contaminating Jupiter. Most scientists opposed to sterilizing the probe argue that to order the probe sterilized would be the death of the project, since sterilization would entail a reconstruction of the probe, and there are not enough funds to accomplish this. These scientists, however, are ignoring a relatively simple and inexpensive alternative to the traditional heat sterilization method. The main threat of contamination comes from Galileo's exterior surfaces: the shell of the probe and its parachute. The probe innermost components would not represent a threat since the probe is sealed. In light of the fact that only the exterior of Galileo would have to be sterilized, heat would not have to be used as a method of sterilization. Instead, various gas mixtures could be sprayed entirely over the probe and its parachute, gases which would kill any and all bacteria. This idea is more thoroughly examined.

  5. Hot Jupiters and cool stars

    Energy Technology Data Exchange (ETDEWEB)

    Villaver, Eva; Mustill, Alexander J. [Department of Theoretical Physics, Universidad Autónoma de Madrid, Módulo 8, 28049 Madrid (Spain); Livio, Mario [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Siess, Lionel, E-mail: eva.villaver@uam.es [Institut d' Astronomie et d' Astrophysique, Université Libre de Bruxelles, B-1050 Bruxelles (Belgium)

    2014-10-10

    Close-in planets are in jeopardy, as their host stars evolve off the main sequence (MS) to the subgiant and red giant phases. In this paper, we explore the influences of the stellar mass (in the range 1.5-2 M {sub ☉}), mass-loss prescription, planet mass (from Neptune up to 10 Jupiter masses), and eccentricity on the orbital evolution of planets as their parent stars evolve to become subgiants and red giants. We find that planet engulfment along the red giant branch is not very sensitive to the stellar mass or mass-loss rates adopted in the calculations, but quite sensitive to the planetary mass. The range of initial separations for planet engulfment increases with decreasing mass-loss rates or stellar masses and increasing planetary masses. Regarding the planet's orbital eccentricity, we find that as the star evolves into the red giant phase, stellar tides start to dominate over planetary tides. As a consequence, a transient population of moderately eccentric close-in Jovian planets is created that otherwise would have been expected to be absent from MS stars. We find that very eccentric and distant planets do not experience much eccentricity decay, and that planet engulfment is primarily determined by the pericenter distance and the maximum stellar radius.

  6. Gas mission; Mission gaz

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This preliminary report analyses the desirable evolutions of gas transport tariffing and examines some questions relative to the opening of competition on the French gas market. The report is made of two documents: a synthesis of the previous report with some recommendations about the tariffing of gas transport, about the modalities of network access to third parties, and about the dissociation between transport and trade book-keeping activities. The second document is the progress report about the opening of the French gas market. The first part presents the European problem of competition in the gas supply and its consequences on the opening and operation of the French gas market. The second part presents some partial syntheses about each topic of the mission letter of the Ministry of Economics, Finances and Industry: future evolution of network access tariffs, critical analysis of contractual documents for gas transport and delivery, examination of auxiliary services linked with the access to the network (modulation, balancing, conversion), consideration about the processing of network congestions and denied accesses, analysis of the metering dissociation between the integrated activities of gas operators. Some documents are attached in appendixes: the mission letter from July 9, 2001, the detailed analysis of the new temporary tariffs of GdF and CFM, the offer of methane terminals access to third parties, the compatibility of a nodal tariffing with the presence of three transport operators (GdF, CFM and GSO), the contract-type for GdF supply, and the contract-type for GdF connection. (J.S.)

  7. The EJSM Jupiter-Europa Orbiter: Planning Payload

    Science.gov (United States)

    Tan-Wang, G.; Pappalardo, R. T.; Boldt, J.; Clark, K.; Greeley, R.; Hendrix, A. R.; Lock, R. E.; van Houten, T.; Ludwinski, J.

    2008-12-01

    In the decade since the first return of Europa data by the Galileo spacecraft, the scientific understanding of Europa has greatly matured leading to the formulation of sophisticated new science objectives to be addressed through the acquisition of new data. The Jupiter-Europa Orbiter (JEO) is one component of the proposed multi-spacecraft Europa Jupiter System Mission (EJSM) designed to obtain data in support of these new science objectives. The JEO planning payload, while notional, is used to quantify engineering aspects of the mission and spacecraft design, and operational scenarios required to obtain the data necessary to meet the science objectives. The instruments were defined to demonstrate the viability of meeting the measurement objectives, performing while in the background radiation environment, and the ability to meet stringent planetary protection requirements. The actual instrument suite would ultimately be the result of an Announcement of Opportunity (AO) selection process carried out by NASA. The JEO planning payload consists of a notional set of remote sensing instruments, fields-and-plasma instruments, and both X-band and Ka band telecommunications systems which provide Doppler and range data for accurate orbit reconstruction. For JEO, the sensor portions of the instruments are located on the nadir facing deck of the spacecraft while a shared chassis houses the electronics portion of the instruments making optimal use of radiation shielding mass. A spacecraft supplied 10 meter boom is deployed for use by the JEO Magnetometer. All instruments are co-aligned and nominally nadir pointing for simplification of spacecraft operations. Instrument articulation required for target motion compensation, limb viewing or other purposes will be implemented within the instrument. Spacecraft telemetry and telecommand interfaces are nominally Spacewire for high-bandwidth instruments and Mil-Std-1553 for low-bandwidth instruments. Instrument power is provided by a

  8. The Juno New Frontier Mission: Inside and Out

    Science.gov (United States)

    Connerney, Jack; Bolton, Scott; Levin, Steve

    2016-04-01

    In July 2016, after almost 5 years en route, NASA's Juno spacecraft will be inserted into polar orbit about Jupiter to begin a two-year mission of discovery unlike any that preceded it. Juno's orbit is a high inclination "mapping" orbit, designed to pass from just above the cloudtops at perijove to the distant magnetosphere (>40 Rj) at apojove. This orbit serves the study of Jupiter's origin, interior structure, and deep atmosphere, via global measurements of gravity, magnetic fields, and atmospheric composition to great depth; it also provides the first comprehensive in-situ observations of the polar magnetosphere and auroral regions. The re-planned Juno mission profile provides a months-long approach phase from the dawn side of Jupiter's magnetosphere, facilitating a study of upstream phenomena and the response of the aurora to solar wind drivers. Two 53-day capture orbits, also near dawn local time, follow orbit insertion (July 4) and provide an opportunity to characterize the distant magnetosphere and magnetosheath. If all goes as planned during the first few perijoves, another maneuver will reduce Juno's orbit period to 14 days, providing a set of at least thirty two 14-day science orbits with the spacecraft flying over Jupiter's poles and ducking under the radiation belts. The payload consists of a set of microwave antennas for sounding the deep atmosphere, magnetometers, gravity radio science, low and high energy charged particle detectors, electric and magnetic field radio and plasma wave experiment, ultraviolet imaging spectrograph, infrared imager and a visible camera. Juno's measurements of the abundance of Oxygen and Nitrogen in Jupiter's atmosphere, and the detailed maps of Jupiter's gravity and magnetic field structure will constrain theories of early planetary development. The Juno mission design, science goals, and measurements related to the origin of Jupiter will be presented.

  9. Plume and surface feature structure and compositional effects on Europa's global exosphere: Preliminary Europa mission predictions

    Science.gov (United States)

    Teolis, B. D.; Wyrick, D. Y.; Bouquet, A.; Magee, B. A.; Waite, J. H.

    2017-03-01

    A Europa plume source, if present, may produce a global exosphere with complex spatial structure and temporal variability in its density and composition. To investigate this interaction we have integrated a water plume source containing multiple organic and nitrile species into a Europan Monte Carlo exosphere model, considering the effect of Europa's gravity in returning plume ejecta to the surface, and the subsequent spreading of adsorbed and exospheric material by thermal desorption and re-sputtering across the entire body. We consider sputtered, radiolytic and potential plume sources, together with surface adsorption, regolith diffusion, polar cold trapping, and re-sputtering of adsorbed materials, and examine the spatial distribution and temporal evolution of the exospheric density and composition. These models provide a predictive basis for telescopic observations (e.g. HST, JWST) and planned missions to the Jovian system by NASA and ESA. We apply spacecraft trajectories to our model to explore possible exospheric compositions which may be encountered along proposed flybys of Europa to inform the spatial and temporal relationship of spacecraft measurements to surface and plume source compositions. For the present preliminary study, we have considered four cases: Case A: an equatorial flyby through a sputtered only exosphere (no plumes), Case B: a flyby over a localized sputtered 'macula' terrain enriched in non-ice species, Case C: a south polar plume with an Enceladus-like composition, equatorial flyby, and Case D: a south polar plume, flyby directly through the plume.

  10. A 'Moving' Jupiter Global Map (Animation)

    Science.gov (United States)

    2007-01-01

    The Long Range Reconnaissance Imager (LORRI) on New Horizons has acquired six global maps of Jupiter as the spacecraft approaches the giant planet for a close encounter at the end of February. The high-resolution camera acquired each of six observation 'sets' as a series of individual pictures taken one hour apart, covering a full 10-hour rotation of Jupiter. The LORRI team at the Johns Hopkins University Applied Physics Laboratory (APL) reduced the sets to form six individual maps in a simple rectangular projection. These six maps were then combined to make the movie. The table below shows the dates and the ranges from Jupiter at which these six sets of observations were acquired. Even for the latest set of images taken January 21-22, from 60.5 million kilometers (37.6 million miles), New Horizons was still farther from Jupiter than the average distance of Mercury from the Sun. At that distance from Jupiter, a single LORRI picture resolution element amounts to 300 kilometers (186 miles) on Jupiter. Many features seen in Jupiter's atmosphere are giant storm clouds. The Little Red Spot, which LORRI will image close-up on February 27, is the target-like feature located near 30 degrees South and 230 degrees West; this storm is larger than the Earth. The even larger Great Red Spot is seen near 20 degrees South and 320 degrees West. The counterclockwise rotation of the clouds within the Great Red Spot can be seen. The westward drift of the Great Red Spot is easily seen in the movie, as is the slower drift, in the opposite direction, of the Little Red Spot. The storms of Jupiter are not fixed in location relative to each other or relative to any solid surface below, because Jupiter is a fluid planet without a solid surface. Also, dramatic changes are seen in the series of bright plume-like clouds encircling the planet between 0 and 10 degrees North. Scientists believe these result from an enormous atmospheric wave with rising air, rich in ammonia that condenses to form

  11. High precision thermal modeling of complex systems with application to the flyby and Pioneer anomaly

    CERN Document Server

    Rievers, Benny

    2011-01-01

    Thermal modeling of complex systems faces the problems of an effective digitalization of the detailed geometry and properties of the system, calculation of the thermal flows and temperature maps, treatment of the thermal radiation including possible multiple reflections, inclusion of additional external influences, extraction of the radiation pressure from calculated surface data, and computational effectiveness. In previous publications the solution to these problems have been outlined and a first application to the Pioneer spacecraft have been shown. Here we like to present the application of our thermal modeling to the Rosetta flyby anomaly as well as to the Pioneer anomaly. The analysis outlines that thermal recoil pressure is not the cause of the Rosetta flyby anomaly but likely resolves the anomalous acceleration observed for Pioneer 10.

  12. On a correlation among azimuthal velocities and the flyby anomaly sign

    CERN Document Server

    Acedo, L

    2016-01-01

    Data of six flybys, those of Galileo I, Galileo II, NEAR, Cassini, Rosetta and Messenger were reported by Anderson et al \\citep{Anderson}. Four of them: Galileo I, NEAR, Rosetta and Messenger gain Newtonian energy during the flyby transfer, while Galileo II and Cassini lose energy. This is, in both cases, a surprising anomaly since Newtonian forces derive from a potential and they are, therefore, conservative. We show here that the gravitational field of a rotating planet as derived from a new model introduces a non conservative force that gives a partial, but in our opinion satisfactory, explanation of these anomalies and suggests a correlation between the sign of the anomaly and the sign of the azimuthal velocity at perigee.

  13. Revisit of rotational dynamics of Asteroid 4179 Toutatis from Chang'e-2's flyby

    Science.gov (United States)

    Zhao, Yuhui; Hu, Shoucun; Ji, Jianghui

    2016-01-01

    This paper presents analysis of the rotational parameters of Toutatis based on the observational results from Chang'e-2's close flyby. The 3-D shape model derived from ground-based radar observation is used to calculate the 3-1-3 Euler angles at the flyby epoch, which are evaluated to be -20.1° +/- 1°, 27.6° +/- 1° and 42.2° +/- 1°. The large amplitude of Toutatis' tumbling attitude is demonstrated to be the result of the large deviation of the angular momentum axis and the rotational axis. Two rotational periods are evaluated to be 5.38+/-0.03 days for rotation about the long axis and 7.40+/-0.03 days for precession of the long axis about the angular momentum vector based on Fourier analysis. These results provide a further understanding of rotational state of Toutatis.

  14. Evidence for young volcanism on Mercury from the third MESSENGER flyby.

    Science.gov (United States)

    Prockter, Louise M; Ernst, Carolyn M; Denevi, Brett W; Chapman, Clark R; Head, James W; Fassett, Caleb I; Merline, William J; Solomon, Sean C; Watters, Thomas R; Strom, Robert G; Cremonese, Gabriele; Marchi, Simone; Massironi, Matteo

    2010-08-06

    During its first two flybys of Mercury, the MESSENGER spacecraft acquired images confirming that pervasive volcanism occurred early in the planet's history. MESSENGER's third Mercury flyby revealed a 290-kilometer-diameter peak-ring impact basin, among the youngest basins yet seen, having an inner floor filled with spectrally distinct smooth plains. These plains are sparsely cratered, postdate the formation of the basin, apparently formed from material that once flowed across the surface, and are therefore interpreted to be volcanic in origin. An irregular depression surrounded by a halo of bright deposits northeast of the basin marks a candidate explosive volcanic vent larger than any previously identified on Mercury. Volcanism on the planet thus spanned a considerable duration, perhaps extending well into the second half of solar system history.

  15. Revisit of rotational dynamics of Asteroid 4179 Toutatis from Chang'e-2's flyby

    CERN Document Server

    Zhao, Yuhui; Ji, Jianghui

    2015-01-01

    This paper presents analysis of the rotational parameters of Toutatis based on the observational results from Chang'e-2's close flyby. The 3-D shape model derived from ground-based radar observation is used to calculate the 3-1-3 Euler angles at the flyby epoch, which are evaluated to be $-20.1^\\circ\\pm1^\\circ$, $27.6^\\circ\\pm1^\\circ$ and $42.2^\\circ\\pm1^\\circ$. The large amplitude of Toutatis' tumbling attitude is demonstrated to be the result of the large deviation of the angular momentum axis and the rotational axis. Two rotational periods are evaluated to be $5.38\\pm0.03$ days for rotation about the long axis and $7.40\\pm0.03$ days for precession of the long axis about the angular momentum vector based on Fourier analysis. These results provide a further understanding of rotational state of Toutatis.

  16. Surface Irradiation of Jupiter's Moon Europa

    Science.gov (United States)

    Rubin, M.; Tenishev, V.; Combi, M. R.; Jia, X.; Hansen, K. C.; Gombosi, T. I.

    2010-12-01

    Jupiter’s moon Europa has a complex and tightly coupled interaction with the Jovian magnetosphere. Neutral gas of the moon’s exosphere is ionized and picked up by the corotating plasma that sweeps past Europa at a relative velocity of almost 100 km/s. This pick-up process alters the magnetic and electric field topology around Europa, which in turn affects the trajectories of the pick-up ions as well as the thermal and hot magnetospheric ions that hit the moon’s icy surface. In turn these surface-impinging ions are the responsible source for the sputtered neutral atmosphere, which itself is again crucial for the exospheric mass loading of the surrounding plasma. We use the magnetohydrodynamics (MHD) model BATSRUS to model the interaction of Europa with the Jovian magnetosphere. The model accounts for the exospheric mass loading, ion-neutral charge exchange, and ion-electron recombination [Kabin et al. (J. Geophys. Res., 104, A9, 19,983-19,992, 1999)]. The derived magnetic and electric fields are then used in our Test Particle Monte Carlo (TPMC) model to integrate individual particle trajectories under the influence of the Lorentz force. We take the measurements performed by Galileo’s Energetic Particle Detector (EPD) [Williams et al. (Sp. Sci. Rev. 60, 385-412, 1992) and Cooper et al. (Icarus 149, 133-159, 2001)] and the Plasma Analyzer (PLS) [Paterson et al. (J. Geophys. Res., 104, A10, 22,779-22,791, 1999)] as boundary conditions. Using a Monte Carlo technique allows to individually track ions in a wide energy range and to individually calculate their energy deposition on the moon’s surface. The sputtering yield is a function of incident particle type, energy, and mass. We use the measurements performed by Shi et al. (J. Geophys. Res., 100, E12, 26,387-26,395, 1995) to turn the modeled impinging ion flux into a neutral gas production rate at the surface. We will show preliminary results of this work with application to the missions to the Jupiter system

  17. Effects of stellar flybys on planetary systems: 3D modeling of the circumstellar disks damping effects

    CERN Document Server

    Picogna, Giovanni

    2014-01-01

    Stellar flybys in star clusters are suspected to affect the orbital architecture of planetary systems causing eccentricity excitation and orbital misalignment between the planet orbit and the equatorial plane of the star. We explore whether the impulsive changes in the orbital elements of planets, caused by an hyperbolic stellar flyby, can be fully damped by the circumstellar disk surrounding the star. The time required to disperse stellar clusters is in fact comparable to circumstellar disk's lifetime. We have modelled in 3D a system made of a solar type star surrounded by a low density disk with a giant planet embedded in it approached on a hyperbolic encounter trajectory by a second star, of similar mass and with its own disk. We focus on extreme configurations where a very deep stellar flyby perturbs a Jovian planet on an external orbit. This allows to test in full the ability of the disk to erase the effects of the stellar encounter. We find that the amount of mass lost by the disk during the stellar fly...

  18. Phobos - solar wind interaction: Results from Mars Express for the closest-ever fly-by

    Science.gov (United States)

    Barabash, Stas; Holmström, Mats; Futaana, Yoshifumi; Fedorov, Andrei; Frahm, Rudy; Fränz, Markus; Dubinin, Edik

    2014-05-01

    On December 29, 07:09 UT Mars Express performed a Phobos fly-by at a distance of 58 km from the center of Phobos. This is the closest fly-by ever performed by a spacecraft at this Martian moon. The fly-by occurred on the Phobos day side (upstream), in the Martian magnetosheath, close to the induced magnetosphere boundary down-tail. The ASPERA-3 package (Analyzer of Space Plasmas and Energetic Atoms) was searching for any Phobos related disturbances in the ambient plasma. To improve the package performance the ion sensor was re-programmed to achieve a time resolution of 24 s for a full energy - angular sweep, instead of the usual 192 s. The electron sensor operated with the nominal 4 s time resolution. At the time of the abstract submission the data analysis is on-going. No strong signatures unambiguously caused by Phobos have been so far identified in the proton measurements. Neither is seen the presence of any heavy ions. The preliminary results rule out strong outgassing from Phobos. Phobos very likely interacts with the solar wind in the manner similar to the Moon. Phobos regolith absorbs the majority of the impinging solar wind ions and a small fraction of protons get reflected.

  19. Can the flyby anomalies be explained by a modification of inertia?

    CERN Document Server

    McCulloch, M E

    2007-01-01

    The flyby anomalies are unexplained velocity increases of 3.9, 13.5, 0.1 and 1.8 mm/s observed near closest approach during the Earth flybys of the Galileo, NEAR, Cassini and Rosetta spacecraft. Here, these flybys are modelled using a theory that assumes that inertia is caused by a form of Unruh radiation, modified by a Hubble-scale Casimir effect. This theory predicts that when the craft's accelerations relative to the galactic centre approached zero near closest approach, their inertial masses reduced for about 10^-7 s causing Earthward jumps of 2.6, 1.2, 1.4 and 1.9 mm/s respectively, and, to conserve angular momentum, increases in orbital velocity of a few mm/s that, except NEAR's, were quite close to those observed. However, these results were extremely sensitive to the Hubble constant used. As an experimental test of these ideas, it is proposed that metamaterials could be used to bend Unruh radiation around objects, possibly reducing their inertial mass.

  20. Detection and analysis of Jupiter's decametric micropulses

    Science.gov (United States)

    Lebo, G. R.

    1972-01-01

    The occurrence of Jupiter's decametric radio emission can be correlated with the central meridian longitude of Jupiter as if the active regions were radio transmitters placed at fixed longitudes on its surface. These active regions are commonly called sources and are labelled Source A, Jovian longitude = 200 deg, Source B = 100 deg and Source C =300 deg. These sources are not always active. However, they can be turned-on if Jupiter's innermost Galilean moon, Io, is in the right phase. In fact, if Io is found 90 deg from superior geocentric conjunction (maximum eastern elongation) and if source B is simultaneously on the central meridian, source B radiation is almost guaranteed, whereas source C radiation is highly likely when Io is found 240 deg from superior geocentric conjunction. Source A radiation is largely independent of Io's position. Interestingly, the Io-related radio storms contain unusually rapid events that can only be properly studied using wide-band techniques.

  1. Radiation-Hydrodynamics of Hot Jupiter Atmospheres

    CERN Document Server

    Menou, Kristen

    2009-01-01

    Radiative transfer in planetary atmospheres is usually treated in the static limit, i.e., neglecting atmospheric motions. We argue that hot Jupiter atmospheres, with possibly fast (sonic) wind speeds, may require a more strongly coupled treatment, formally in the regime of radiation-hydrodynamics. To lowest order in v/c, relativistic Doppler shifts distort line profiles along optical paths with finite wind velocity gradients. This leads to flow-dependent deviations in the effective emission and absorption properties of the atmospheric medium. Evaluating the overall impact of these distortions on the radiative structure of a dynamic atmosphere is non-trivial. We present transmissivity and systematic equivalent width excess calculations which suggest possibly important consequences for radiation transport in hot Jupiter atmospheres. If winds are fast and bulk Doppler shifts are indeed important for the global radiative balance, accurate modeling and reliable data interpretation for hot Jupiter atmospheres may p...

  2. Capture of Trojans by Jumping Jupiter

    CERN Document Server

    Nesvorny, David; Morbidelli, Alessandro

    2013-01-01

    Jupiter Trojans are thought to be survivors of a much larger population of planetesimals that existed in the planetary region when planets formed. They can provide important constraints on the mass and properties of the planetesimal disk, and its dispersal during planet migration. Here we tested a possibility that the Trojans were captured during the early dynamical instability among the outer planets (aka the Nice model), when the semimajor axis of Jupiter was changing as a result of scattering encounters with an ice giant. The capture occurs in this model when Jupiter's orbit and its Lagrange points become radially displaced in a scattering event and fall into a region populated by planetesimals (that previously evolved from their natal transplanetary disk to ~5 AU during the instability). Our numerical simulations of the new capture model, hereafter jump capture, satisfactorily reproduce the orbital distribution of the Trojans and their total mass. The jump capture is potentially capable of explaining the ...

  3. Jupiter's Great Red Spot and White Ovals

    Science.gov (United States)

    1979-01-01

    This photo of Jupiter was taken by Voyager 1 on the evening of March 1, 1979, from a distance of 2.7 million miles (4.3 million kilometers). The photo shows Jupiter's Great Red Spot (top) and one of the white ovals than can be seen in Jupiter's atmosphere from Earth. The white ovals were seen to form in 1939, and 1940, and have remained more or less constant ever since. None of the structure and detail evident in these features have ever been seen from Earth. The Great Red Spot is three times as large as Earth. Also evident in the picture is a great deal of atmospheric detail that will require further study for interpretation. The smallest details that can be seen in this picture are about 45 miles (80 kilometers across. JPL manages and controls the Voyager project for NASA's Office of Space Science.

  4. Capture of Irregular Satellites at Jupiter

    CERN Document Server

    Nesvorny, D; Deienno, R

    2014-01-01

    The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early Solar System instability when encounters between the outer planets occurred (Nesvorny, Vokrouhlicky & Morbidelli 2007, AJ 133; hereafter NVM07). NVM07 already showed that the irregular satellites of Saturn, Uranus and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary d...

  5. Ion Mass Spectrometer Development for JEO Class Missions

    Science.gov (United States)

    Sittler, E. C.; Cooper, J. F.; Paschalidis, N.; Coplan, M. A.; Chornay, D. J.; Sturner, S. J.; Brown, S. K.; Hartle, R. E.; Paterson, W. R.

    2012-10-01

    Under the Astrobiology Instrument Development Program we have been developing an advanced 3-D ion mass spectrometer (IMS) from 10 V to 30 kV, that can be proposed for missions to Jupiter's icy moons, Uranus, Titan, asteroids, comets, and solar wind.

  6. The Bering small vehicle asteroid mission concept

    DEFF Research Database (Denmark)

    Michelsen, Rene; Andersen, Anja; Haack, Henning

    2004-01-01

    targets. The dilemma obviously being the resolution versus distance and the statistics versus DeltaV requirements. Using advanced instrumentation and onboard autonomy, we have developed a space mission concept whose goal is to map the flux, size, and taxonomy distributions of asteroids. The main focus......The study of asteroids is traditionally performed by means of large Earth based telescopes, by means of which orbital elements and spectral properties are acquired. Space borne research, has so far been limited to a few occasional flybys and a couple of dedicated flights to a single selected target....... Although the telescope based research offers precise orbital information, it is limited to the brighter, larger objects, and taxonomy as well as morphology resolution is limited. Conversely, dedicated missions offer detailed surface mapping in radar, visual, and prompt gamma, but only for a few selected...

  7. Thermal tides on a hot Jupiter

    Directory of Open Access Journals (Sweden)

    Hsieh H.-F.

    2011-07-01

    Full Text Available Following the linear analysis laid out by Gu & Ogilvie 2009 (hereafter GO09, we investigate the dynamical response of a non-synchronized hot Jupiter to stellar irradiation. Besides the internal and Rossby waves considered by GO09, we study the Kelvin waves excited by the diurnal Fourier harmonic of the prograde stellar irradiation. We also present a 2-dimensional plot of internal waves excited by the semi-diurnal component of the stellar irradiation and postulate that thermal bulges may arise in a hot Jupiter. Whether our postulation is valid and is consistent with the recent results from Arras & Socrates (2009b requires further investigation.

  8. Jupiter after Pioneer - A progress report

    Science.gov (United States)

    Mcdonough, T. R.

    1974-01-01

    In December 1973, Pioneer 10 became the first spacecraft to reach the vicinity of Jupiter. The spacecraft passed through the Jovian magnetosphere in two weeks and sent back more than 300 pictures of the big planet. Measurements were conducted of EM fields, energetic particles, and micrometeoroids. Radio occultations observed are discussed along with observations in the infrared and ultraviolet range, magnetic measurements, questions of trajectory analysis, and data obtained with the aid of a plasma analyzer. Pioneer 10 has confirmed as inescapable the fact that Jupiter radiates more energy than it receives from the sun.

  9. HUBBLE PROVIDES COMPLETE VIEW OF JUPITER'S AURORAS

    Science.gov (United States)

    2002-01-01

    NASA's Hubble Space Telescope has captured a complete view of Jupiter's northern and southern auroras. Images taken in ultraviolet light by the Space Telescope Imaging Spectrograph (STIS) show both auroras, the oval- shaped objects in the inset photos. While the Hubble telescope has obtained images of Jupiter's northern and southern lights since 1990, the new STIS instrument is 10 times more sensitive than earlier cameras. This allows for short exposures, reducing the blurring of the image caused by Jupiter's rotation and providing two to five times higher resolution than earlier cameras. The resolution in these images is sufficient to show the 'curtain' of auroral light extending several hundred miles above Jupiter's limb (edge). Images of Earth's auroral curtains, taken from the space shuttle, have a similar appearance. Jupiter's auroral images are superimposed on a Wide Field and Planetary Camera 2 image of the entire planet. The auroras are brilliant curtains of light in Jupiter's upper atmosphere. Jovian auroral storms, like Earth's, develop when electrically charged particles trapped in the magnetic field surrounding the planet spiral inward at high energies toward the north and south magnetic poles. When these particles hit the upper atmosphere, they excite atoms and molecules there, causing them to glow (the same process acting in street lights). The electrons that strike Earth's atmosphere come from the sun, and the auroral lights remain concentrated above the night sky in response to the 'solar wind,' as Earth rotates underneath. Earth's auroras exhibit storms that extend to lower latitudes in response to solar activity, which can be easily seen from the northern U. S. But Jupiter's auroras are caused by particles spewed out by volcanoes on Io, one of Jupiter's moons. These charged particles are then magnetically trapped and begin to rotate with Jupiter, producing ovals of auroral light centered on Jupiter's magnetic poles in both the day and night skies

  10. TandEM: Titan and Enceladus mission

    Science.gov (United States)

    Coustenis, A.; Atreya, S.K.; Balint, T.; Brown, R.H.; Dougherty, M.K.; Ferri, F.; Fulchignoni, M.; Gautier, D.; Gowen, R.A.; Griffith, C.A.; Gurvits, L.I.; Jaumann, R.; Langevin, Y.; Leese, M.R.; Lunine, J.I.; McKay, C.P.; Moussas, X.; Muller-Wodarg, I.; Neubauer, F.; Owen, T.C.; Raulin, F.; Sittler, E.C.; Sohl, F.; Sotin, C.; Tobie, G.; Tokano, T.; Turtle, E.P.; Wahlund, J.-E.; Waite, J.H.; Baines, K.H.; Blamont, J.; Coates, A.J.; Dandouras, I.; Krimigis, T.; Lellouch, E.; Lorenz, R.D.; Morse, A.; Porco, C.C.; Hirtzig, M.; Saur, J.; Spilker, T.; Zarnecki, J.C.; Choi, E.; Achilleos, N.; Amils, R.; Annan, P.; Atkinson, D.H.; Benilan, Y.; Bertucci, C.; Bezard, B.; Bjoraker, G.L.; Blanc, M.; Boireau, L.; Bouman, J.; Cabane, M.; Capria, M.T.; Chassefiere, E.; Coll, P.; Combes, M.; Cooper, J.F.; Coradini, A.; Crary, F.; Cravens, T.; Daglis, I.A.; de Angelis, E.; De Bergh, C.; de Pater, I.; Dunford, C.; Durry, G.; Dutuit, O.; Fairbrother, D.; Flasar, F.M.; Fortes, A.D.; Frampton, R.; Fujimoto, M.; Galand, M.; Grasset, O.; Grott, M.; Haltigin, T.; Herique, A.; Hersant, F.; Hussmann, H.; Ip, W.; Johnson, R.; Kallio, E.; Kempf, S.; Knapmeyer, M.; Kofman, W.; Koop, R.; Kostiuk, T.; Krupp, N.; Kuppers, M.; Lammer, H.; Lara, L.-M.; Lavvas, P.; Le, Mouelic S.; Lebonnois, S.; Ledvina, S.; Li, J.; Livengood, T.A.; Lopes, R.M.; Lopez-Moreno, J. -J.; Luz, D.; Mahaffy, P.R.; Mall, U.; Martinez-Frias, J.; Marty, B.; McCord, T.; Salvan, C.M.; Milillo, A.; Mitchell, D.G.; Modolo, R.; Mousis, O.; Nakamura, M.; Neish, C.D.; Nixon, C.A.; Mvondo, D.N.; Orton, G.; Paetzold, M.; Pitman, J.; Pogrebenko, S.; Pollard, W.; Prieto-Ballesteros, O.; Rannou, P.; Reh, K.; Richter, L.; Robb, F.T.; Rodrigo, R.; Rodriguez, S.; Romani, P.; Bermejo, M.R.; Sarris, E.T.; Schenk, P.; Schmitt, B.; Schmitz, N.; Schulze-Makuch, D.; Schwingenschuh, K.; Selig, A.; Sicardy, B.; Soderblom, L.; Spilker, L.J.; Stam, D.; Steele, A.; Stephan, K.; Strobel, D.F.; Szego, K.; Szopa,

    2009-01-01

    TandEM was proposed as an L-class (large) mission in response to ESA's Cosmic Vision 2015-2025 Call, and accepted for further studies, with the goal of exploring Titan and Enceladus. The mission concept is to perform in situ investigations of two worlds tied together by location and properties, whose remarkable natures have been partly revealed by the ongoing Cassini-Huygens mission. These bodies still hold mysteries requiring a complete exploration using a variety of vehicles and instruments. TandEM is an ambitious mission because its targets are two of the most exciting and challenging bodies in the Solar System. It is designed to build on but exceed the scientific and technological accomplishments of the Cassini-Huygens mission, exploring Titan and Enceladus in ways that are not currently possible (full close-up and in situ coverage over long periods of time). In the current mission architecture, TandEM proposes to deliver two medium-sized spacecraft to the Saturnian system. One spacecraft would be an orbiter with a large host of instruments which would perform several Enceladus flybys and deliver penetrators to its surface before going into a dedicated orbit around Titan alone, while the other spacecraft would carry the Titan in situ investigation components, i.e. a hot-air balloon (Montgolfi??re) and possibly several landing probes to be delivered through the atmosphere. ?? Springer Science + Business Media B.V. 2008.

  11. Microwave Radiometers from 0.6 to 22 GHz for Juno, A Polar Orbiter Around Jupiter

    Science.gov (United States)

    Pingree, P.; Janssen, M.; Oswald, J.; Brown, S.; Chen, J.; Hurst, K.; Kitiyakara, A.; Maiwald, F.; Smith, S.

    2008-01-01

    A compact instrument called the MWR (MicroWave Radiometer) is under development at JPL for Juno, the next NASA New Frontiers mission, scheduled to launch in 2011. It's purpose is to measure the thermal emission from Jupiter's atmosphere at six selected frequencies from 0.6 to 22 GHz, operating in direct detection mode, in order to quantify the distributions and abundances of water and ammonia in Jupiter's atmosphere. The goal is to understand the previously unobserved dynamics of the sub-cloud atmosphere, and to discriminate among models for planetary formation in our solar system. As part of a deep space mission aboard a solar-powered spacecraft, MWR is designed to be compact, lightweight, and low power. The receivers and control electronics are protected by a radiation-shielding enclosure on the Juno spacecraft that would provide a benign and stable operating temperature environment. All antennas and RF transmission lines outside the vault must withstand low temperatures and the harsh radiation environment surrounding Jupiter. This paper describes the concept of the MWR instrument and presents results of one breadboard receiver channel.

  12. X-Ray Probes of Jupiter's Auroral Zones, Galilean Moons, and the Io Plasma Torus

    Science.gov (United States)

    Elsner, R. F.; Ramsey, B. D.; Swartz, D. A.; Rehak, P.; Waite, J. H., Jr.; Cooper, J. F.; Johnson, R. E.

    2005-01-01

    Remote observations from the Earth orbiting Chandra X-ray Observatory and the XMM-Newton Observatory have shown the the Jovian system is a rich and complex source of x-ray emission. The planet's auroral zones and its disk are powerful sources of x-ray emission, though with different origins. Chandra observations discovered x-ray emission from the Io plasma torus and from the Galilean moons Io, Europa, and possibly Ganymede. The emission from the moons is due to bombardment of their surfaces by highly energetic magnetospheric protons, and oxygen and sulfur ions, producing fluorescent x-ray emission lines from the elements in their surfaces against an intense background continuum. Although very faint when observed from Earth orbit, an imaging x-ray spectrometer in orbit around the icy Galilean moons would provide a detail mapping of the elemental composition in their surfaces. Here we review the results of Chandra and XMM-Newton observations of the Jovian system and describe the characteristics of X-MIME, an imaging x-ray spectrometer undergoing study for possible application to future missions to Jupiter such as JIMO. X-MIME has the ultimate goal of providing detailed high-resolution maps of the elemental abundances of the surfaces of Jupiter's icy moons and Io, as well as detailed study of the x-ray mission from the Io plasma torus, Jupiter's auroral zones, and the planetary disk.

  13. The New Planetary Science Archive (PSA): Exploration and Discovery of Scientific Datasets from ESA's Planetary Missions

    Science.gov (United States)

    Heather, David; Besse, Sebastien; Vallat, Claire; Barbarisi, Isa; Arviset, Christophe; De Marchi, Guido; Barthelemy, Maud; Coia, Daniela; Costa, Marc; Docasal, Ruben; Fraga, Diego; Grotheer, Emmanuel; Lim, Tanya; MacFarlane, Alan; Martinez, Santa; Rios, Carlos; Vallejo, Fran; Saiz, Jaime

    2017-04-01

    The Planetary Science Archive (PSA) is the European Space Agency's (ESA) repository of science data from all planetary science and exploration missions. The PSA provides access to scientific datasets through various interfaces at http://psa.esa.int. All datasets are scientifically peer-reviewed by independent scientists, and are compliant with the Planetary Data System (PDS) standards. The PSA is currently implementing a number of significant improvements, mostly driven by the evolution of the PDS standard, and the growing need for better interfaces and advanced applications to support science exploitation. As of the end of 2016, the PSA is hosting data from all of ESA's planetary missions. This includes ESA's first planetary mission Giotto that encountered comet 1P/Halley in 1986 with a flyby at 800km. Science data from Venus Express, Mars Express, Huygens and the SMART-1 mission are also all available at the PSA. The PSA also contains all science data from Rosetta, which explored comet 67P/Churyumov-Gerasimenko and asteroids Steins and Lutetia. The year 2016 has seen the arrival of the ExoMars 2016 data in the archive. In the upcoming years, at least three new projects are foreseen to be fully archived at the PSA. The BepiColombo mission is scheduled for launch in 2018. Following that, the ExoMars Rover Surface Platform (RSP) in 2020, and then the JUpiter ICy moon Explorer (JUICE). All of these will archive their data in the PSA. In addition, a few ground-based support programmes are also available, especially for the Venus Express and Rosetta missions.
 The newly designed PSA will enhance the user experience and will significantly reduce the complexity for users to find their data promoting one-click access to the scientific datasets with more customized views when needed. This includes a better integration with Planetary GIS analysis tools and Planetary interoperability services (search and retrieve data, supporting e.g. PDAP, EPN-TAP). It will also be up

  14. Inferring the depth of the atmospheric circulation on Jupiter and Saturn through the gravity measurements by Juno and Cassini

    Science.gov (United States)

    Kaspi, Y.; Galanti, E.

    2014-04-01

    In approximately two years the Juno and Cassini spacecraft will both perform close flybys of Jupiter and Saturn respectively, obtaining for the first time a high precision gravity spectrum for these planets. We discuss how this data can be used to estimate the depth of the observed jet streams on these planets. This can be done in several ways: 1. measurements of the high order even harmonics which beyond J10 are dominated by the dynamics; 2. measurements of odd gravity harmonics which have no contribution from a static planet, and therefore are a pure signature of dynamics; 3. upper limits on the depth can be obtained by comparing low order even harmonics from dynamical models to the difference between the measured low order even harmonics and the largest possible values of a static planet; 4. direct latitudinally varying measurements of the gravity field exerted on the spacecraft. We discuss how these methods may be applied and show that given the expected sensitivities of Juno and Cassini the odd harmonics J3 and J5 will have the best sensitivity to deep dynamics, allowing detection of winds reaching only ~ 100 km deep, if those exist on Jupiter and Saturn (Kaspi, 2013). For this analysis we use a hierarchy of dynamical models ranging from deep compressible GCMs to simplified thermal wind models in order to relate the three-dimensional flow to perturbations of the density field, and therefore to the gravity field.

  15. The source of widespread 3-$\\mu$m absorption in Jupiter's clouds: Constraints from 2000 Cassini VIMS observations

    CERN Document Server

    Sromovsky, Lawrence

    2015-01-01

    The Cassini flyby of Jupiter in 2000 provided spatially resolved spectra of Jupiter's atmosphere using the Visual and Infrared Mapping Spectrometer (VIMS). These spectra contain a strong absorption at wavelengths from about 2.9 $\\mu$m to 3.1 $\\mu$m, previously noticed in a 3-$\\mu$m spectrum obtained by the Infrared Space Observatory (ISO) in 1996. While Brooke et al. (1998, Icarus 136, 1-13) were able to fit the ISO spectrum very well using ammonia ice as the sole source of particulate absorption, Sromovsky and Fry (2010, Icarus 210, 211-229), using significantly revised NH$_3$ gas absorption models, showed that ammonium hydrosulfide (NH$_4$SH) provided a better fit to the ISO spectrum than NH$_3$ , but that the best fit was obtained when both NH$_3$ and NH$_4$SH were present. Although the large FOV of the ISO instrument precluded identification of the spatial distribution of these two components, the VIMS spectra at low and intermediate phase angles show that 3-$\\mu$m absorption is present in zones and belts...

  16. "Sniffing" Jupiter's moon Europa through ground-based IR observations

    Science.gov (United States)

    Paganini, Lucas; Mumma, Michael J.; Hurford, Terry; Roth, Lorenz; Villanueva, Geronimo Luis

    2016-10-01

    The ability to sample possible plumes from the subsurface ocean in Europa represents a major step in our search for extraterrestrial life. If plumes exist, sampling the effluent material would provide insights into their chemistry and relevant information about the prospect that life could exist, or now exists, within the ocean. Most of the difficulties in detecting plumes come from the less frequent observational coverage of Europa, which contrasts strongly with the frequent Cassini flybys of Enceladus (Spencer & Nimmo 2013). Recent observations have been taken with HST/STIS in 2014/2015, but results have shown no evident confirmation of the 2012 plume detection (Roth et al. 2014, 2015). Future in situ observations (Europa Mission) will provide definitive insights, but not before the spacecraft's arrival in ~2025, thus an interim approach is needed to inform such space mission planning and to complement existing observations at other wavelengths.In 2015, we initiated a strong campaign to build a comprehensive survey of possible plumes on Europa through high-resolution IR spectroscopy with Keck/NIRSPEC. We were awarded 10 nights out of 15 total nights available for Key Strategic Mission Support projects for the 2016A, 2016B, 2017A, and 2017B semesters under NASA time with the Keck Observatory. In 2016A, we observed Europa during 10 half-nights and will continue to do so for another 10 half-nights in 2017A. We target a serendipitous search of gaseous activity from Europa to confirm and constrain the chemical composition of possible Europan plumes that can aid the investigation of physical processes underlying (or on) its surface. Ultimately, we seek to: (1) provide information that can inform planning for NASA's Europa mission, (2) further our current understanding of Europa's gas environment, and (3) complement studies that are currently underway with other facilities (like the Hubble Space Telescope). In this presentation, we will discuss preliminary results

  17. Assessing the Time Variability of Jupiter's Tropospheric Properties from 1996 to 2011

    Science.gov (United States)

    Orton, G. S.; Fletcher, L. N.; Yanamandra-Fisher, P. A.; Simon-Miller, A. A.; Greco, J.; Wakefield, L.

    2012-01-01

    We acquired and analyzed mid-infrared images of Jupiter's disk at selected wavelengths from NASA's Infrared Telescope Facility (IRTF) from 1996 to 2011, including a period of large-scale changes of cloud color and albedo. We derived the 100-300 mbar temperature structure, together with tracers of vertical motion: the thickness of a 600- mbar cloud layer, the 300-mbar abundance of the condensable gas NH3, and the 400- mbar para- vs. ortho-H2 ratio. The biggest visual change was detected in the normally dark South Equatorial Belt (SEB) that 'faded' to a light color in 2010, during which both cloud thickness and NH3 abundance rose; both returned to their pre-fade levels in 2011, as the SEB regained its normal dark color. The cloud thickness in Jupiter's North Temperate Belt (NTB) increased in 2002, coincident with its visible brightening, and its NH3 abundance spiked in 2002-2003. Jupiter's Equatorial Zone (EZ), a region marked by more subtle but widespread color and albedo change, showed high cloud thickness variability between 2007 and 2009. In Jupiter's North Equatorial Belt (NEB), the cloud thickened in 2005, then slowly decreased to a minimum value in 2010-2011. No temperature variations were associated with any of these changes, but we discovered temperature oscillations of approx.2-4 K in all regions, with 4- or 8-year periods and phasing that was dissimilar in the different regions. There was also no detectable change in the para- vs. ortho-H2 ratio over time, leading to the possibility that it is driven from much deeper atmospheric levels and may be time-invariant. Our future work will continue to survey the variability of these properties through the Juno mission, which arrives at Jupiter in 2016, and to connect these observations with those made using raster-scanned images from 1980 to 1993 (Orton et al. 1996 Science 265, 625).

  18. Mass Spectrometry in Jupiter's Atmosphere: Vertical Variation of Volatile Vapors

    Science.gov (United States)

    Wong, Michael H.; Atreya, Sushil K.; Mahaffy, Paul R.

    2014-05-01

    bulk abundances and spatial variation of these species will be further constrained by the Juno mission, scheduled to arrive at Jupiter in 2016. References: [1] Niemann, H.B. et al. 1992, SSRv 60, 111-142 [2] Niemann, H.B. et al. 1996, Science 272, 846-849 [3] Niemann, H.B. et al. 1998, JGR 103, 22831-22845 [4] Mahaffy, P.R. et al. 2000, JGR 105, 15061-15071 [5] Wong, M.H. et al. 2004, Icarus 171, 153-170 [6] Atreya, S.K. et al., 1999, Planet. Space Sci. 47, 1243-1262 [7] Atreya, S.K. et al., 2003, Planet. Space Sci. 451, 105-112 [8] Wong, M.H. et al., 2008, in Reviews in Mineralogy and Geochemistry, vol. 68. Mineralogical Society of America, Chantilly, VA, pp. 219-246 [9] Wong, M.H., 2009, Icarus 199, 231-235

  19. On the influence of the plasma generated by comet Shoemaker-Levy 9 on Jupiter`s magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Stabile, F.; Zimbardo, G. [Arcavacata di Rende, Cosenza, Univ. della Calabria (Italy). Dipt. di Fisica

    1997-11-01

    The impact of comet Shoemaker-Levy 9 with Jupiter has created a variety of magnetospheric plasmas which were detected by their electromagnetic emissions. By means of the Dessler-Parker-Sckopke relation we estimate the perturbation of Jupiter`s magnetic field. It appears that the produced plasma may explain the observed decrease of UV lines in Io`s torus.

  20. The Science Operations of the ESA JUICE mission

    Science.gov (United States)

    Altobelli, Nicolas; Cardesin, Alejandro; Costa, Marc; Frew, David; Lorente, Rosario; Vallat, Claire; Witasse, Olivier; Christian, Erd

    2016-10-01

    The JUpiter ICy moons Explorer (JUICE) mission was selected by ESA as the first L-Class Mission in the Cosmic Vision Programme. JUICE is an ESA-led mission to investigate Jupiter, the Jovian system with particular focus on habitability of Ganymede and Europa.JUICE will characterise Ganymede and Europa as planetary objects and potential habitats, study Ganymede, Europa, Callisto and Io in the broader context of the system of Jovian moons, and focus on Jupiter science including the planet, its atmosphere and the magnetosphere as a coupled system.The Science Operation Centre (SOC) is in charge of implementing the science operations of the JUICE mission. The SOC aims at supporting the Science Working Team (SWT) and the Science Working Groups (WGs) performing studies of science operation feasibility and coverage analysis during the mission development phase, high level science planning during the cruise phase, and routine consolidation of instrument pointing and commanding timeline during the nominal science phase.We will present the current status of the SOC science planning activities with an overview of the tools and methods in place in this early phase of the mission.

  1. Comparative magnetotail flapping: an overview of selected events at Earth, Jupiter and Saturn

    Directory of Open Access Journals (Sweden)

    M. Volwerk

    2013-05-01

    Full Text Available A comparison of magnetotail flapping (the up-and-down wavy motion between the Earth and the two giant planets Jupiter and Saturn has been performed through investigation of the current sheet normal of the magnetotail. Magnetotail flapping is commonly observed in the Earth's magnetotail. Due to single spacecraft missions at the giant planets, the normal is determined through minimum variance analysis of magnetometer data during multiple intervals when the spacecraft crossed through the current sheet. It is shown that indeed a case can be made that magnetotail flapping also occurs at Jupiter and Saturn. Calculations of the wave period using generic magnetotail models show that the observed periods are much shorter than their theoretical estimates, and that this discrepancy can be caused by unknown input parameters for the tail models (e.g., current sheet thickness and by possible Doppler shifting of the waves in the spacecraft frame through the fast rotation of the giant planets.

  2. JUPITER PROJECT - MERGING INVERSE PROBLEM FORMULATION TECHNOLOGIES

    Science.gov (United States)

    The JUPITER (Joint Universal Parameter IdenTification and Evaluation of Reliability) project seeks to enhance and build on the technology and momentum behind two of the most popular sensitivity analysis, data assessment, calibration, and uncertainty analysis programs used in envi...

  3. Dramatic Change in Jupiter's Great Red Spot

    Science.gov (United States)

    Simon, A. A.; Wong, M. H.; Rogers, J. H.; Orton, G. S.; de Pater, I.; Asay-Davis, X.; Carlson, R. W.; Marcus, P. S.

    2015-01-01

    Jupiter's Great Red Spot (GRS) is one of its most distinct and enduring features, having been continuously observed since the 1800's. It currently spans the smallest latitude and longitude size ever recorded. Here we show analyses of 2014 Hubble spectral imaging data to study the color, structure and internal dynamics of this long-live storm.

  4. Towards Chemical Constraints on Hot Jupiter Migration

    CERN Document Server

    Madhusudhan, Nikku; Kennedy, Grant M

    2014-01-01

    The origin of hot Jupiters -- gas giant exoplanets orbiting very close to their host stars -- is a long-standing puzzle. Planet formation theories suggest that such planets are unlikely to have formed in-situ but instead may have formed at large orbital separations beyond the snow line and migrated inward to their present orbits. Two competing hypotheses suggest that the planets migrated either through interaction with the protoplanetary disk during their formation, or by disk-free mechanisms such as gravitational interactions with a third body. Observations of eccentricities and spin-orbit misalignments of hot Jupiter systems have been unable to differentiate between the two hypotheses. In the present work, we suggest that chemical depletions in hot Jupiter atmospheres might be able to constrain their migration mechanisms. We find that sub-solar carbon and oxygen abundances in Jovian-mass hot Jupiters around Sun-like stars are hard to explain by disk migration. Instead, such abundances are more readily expla...

  5. Jupiter as a Giant Cosmic Ray Detector

    CERN Document Server

    Rimmer, Paul B; Helling, Christiane

    2014-01-01

    We explore the feasibility of using the atmosphere of Jupiter to detect Ultra-High-Energy Cosmic Rays (UHECR's). The large surface area of Jupiter allows us to probe cosmic rays of higher energies than previously accessible. Cosmic ray extensive air showers in Jupiter's atmosphere could in principle be detected by the Large Area Telescope (LAT) on the Fermi observatory. In order to be observed, these air showers would need to be oriented toward the Earth, and would need to occur sufficiently high in the atmosphere that the gamma rays can penetrate. We demonstrate that, under these assumptions, Jupiter provides an effective cosmic ray "detector" area of $3.3 \\times 10^7$ km$^2$. We predict that Fermi-LAT should be able to detect events of energy $>10^{21}$ eV with fluence $10^{-7}$ erg cm$^{-2}$ at a rate of about one per month. The observed number of air showers may provide an indirect measure of the flux of cosmic rays $\\gtrsim 10^{20}$ eV. Extensive air showers also produce a synchrotron signature that may ...

  6. The Origin of Retrograde Hot Jupiters

    Science.gov (United States)

    Naoz, Smadar; Farr, W.; Lithwick, Y.; Rasio, F.; Teyssandier, J.

    2011-09-01

    The search for extra-solar planets has led to the surprising discovery of many Jupiter-like planets in very close proximity to their host star, the so-called ``hot Jupiters'' (HJ). Even more surprisingly, many of these HJs have orbits that are eccentric or highly inclined with respect to the equator of the star, and some (about 25%) even orbiting counter to the spin direction of the star. This poses a unique challenge to all planet formation models. We show that secular interactions between Jupiter-like planet and another perturber in the system can easily produce retrograde HJ orbits. We show that in the frame of work of secular hierarchical triple system (the so-called Kozai mechanism) the inner orbit's angular momentum component parallel to the total angular momentum (i.e., the z-component of the inner orbit angular momentum) need not be constant. In fact, it can even change sign, leading to a retrograde orbit. A brief excursion to very high eccentricity during the chaotic evolution of the inner orbit allows planet-star tidal interactions to rapidly circularize that orbit, decoupling the planets and forming a retrograde hot Jupiter. We estimate the relative frequencies of retrograde orbits and counter to the stellar spin orbits using Monte Carlo simulations, and find that the they are consistent with the observations. The high observed incidence of planets orbiting counter to the stellar spin direction may suggest that planet--planet secular interactions are an important part of their dynamical history.

  7. Hot Jupiters and Super-Earths

    CERN Document Server

    Mustill, Alexander James; Johansen, Anders

    2016-01-01

    We explore the role of dynamics in shaping planetary system multiplicities, focussing on two particular problems. (1) We propose that the lack of close-in super-Earths in hot Jupiter systems is a signature of the migration history of the hot Jupiters and helps to discriminate between different mechanisms of migration. We present N-body simulations of dynamical migration scenarios where proto-hot Jupiters are excited to high eccentricities prior to tidal circularisation and orbital decay. We show that in this scenario, the eccentric giant planet typically destroys planets in the inner system, in agreement with the observed lack of close super-Earth companions to hot Jupiters. (2) We explore the role of the dynamics of outer systems in affecting the multiplicities of close-in systems such as those discovered by Kepler. We consider specifically the effects of planet--planet scattering and Kozai perturbations on an exterior giant planet on the architecture of the inner system, and evaluate the ability of such sce...

  8. Europa--Jupiter's Icy Ocean Moon

    Science.gov (United States)

    Lowes, L.

    1999-01-01

    Europa is a puzzle. The sixth largest moon in our solar system, Europa confounds and intrigues scientists. Few bodies in the solar system have attracted as much scientific attention as this moon of Jupiter because of its possible subsurface ocean of water. The more we learn about this icy moon, the more questions we have.

  9. JunoCam's Imaging of Jupiter

    Science.gov (United States)

    Orton, Glenn; Hansen, Candice; Momary, Thomas; Caplinger, Michael; Ravine, Michael; Atreya, Sushil; Ingersoll, Andrew; Bolton, Scott; Rogers, John; Eichstaedt, Gerald

    2017-04-01

    Juno's visible imager, JunoCam, is a wide-angle camera (58° field of view) with 4 color filters: red, green and blue (RGB) and methane at 889 nm, designed for optimal imaging of Jupiter's poles. Juno's elliptical polar orbit offers unique views of Jupiter's polar regions with spatial scales as good as 50 km/pixel. At closest approach ("perijove") the images have spatial scale down to ˜3 km/pixel. As a push-frame imager on a rotating spacecraft, JunoCam uses time-delayed integration to take advantage of the spacecraft spin to extend integration time to increase signal. Images of Jupiter's poles reveal a largely uncharted region of Jupiter, as nearly all earlier spacecraft except Pioneer 11 have orbited or flown by close to the equatorial plane. Poleward of 64-68° planetocentric latitude, Jupiter's familiar east-west banded structure breaks down. Several types of discrete features appear on a darker, bluish-cast background. Clusters of circular cyclonic spirals are found immediately around the north and south poles. Oval-shaped features are also present, ranging in size down to JunoCam's resolution limits. The largest and brightest features usually have chaotic shapes; animations over ˜1 hour can reveal cyclonic motion in them. Narrow linear features traverse tens of degrees of longitude and are not confined in latitude. JunoCam also detected optically thin clouds or hazes that are illuminated beyond the nightside ˜1-bar terminator; one of these detected at Perijove lay some 3 scale heights above the main cloud deck. Tests have been made to detect the aurora and lightning. Most close-up images of Jupiter have been acquired at lower latitudes within 2 hours of closest approach. These images aid in understanding the data collected by other instruments on Juno that probe deeper in the atmosphere. When Jupiter was too close to the sun for ground-based observers to collect data between perijoves 1 and 2, JunoCam took a sequence of routine images to monitor large

  10. The microwave opacity of ammonia and water vapor: Application to remote sensing of the atmosphere of Jupiter

    Science.gov (United States)

    Hanley, Thomas Ryan

    2008-06-01

    The object of this research program has been to provide a baseline for microwave remote sensing of ammonia and water vapor in the atmosphere of Jupiter through laboratory measurements of their microwave absorption properties. Jupiter is not only the largest planet in our solar system, but one of the most interesting and complex. Despite a handful of spacecraft missions and many astronomical measurements, much of Jupiter's atmospheric dynamics and composition remain a mystery. Although constraints have been formed on the amount of certain gases present, the global abundances and distributions of water vapor (H 2 O) and ammonia (NH 3 ) are relatively unknown. Measurements of H 2 O and NH 3 in the Jovian atmosphere to hundreds of bars of pressure are best accomplished via passive microwave emission measurements. For these measurements to be accurately interpreted, however, the hydrogen and helium pressure-broadened microwave opacities of H 2 O and NH 3 must be well characterized, a task that is very difficult if based solely on theory and limited laboratory measurements. Therefore, accurate laboratory measurements have been taken under a broad range of conditions that mimic those of the Jovian atmosphere. These measurements, performed using a newly redesigned high- accuracy system, and the corresponding models of microwave opacity that have been developed from them comprise the majority of this work. The models allow more accurate retrievals of H 2 O and NH 3 abundances from previous as well as future missions to Jupiter and the outer planets, such as the NASA New Frontiers class Juno mission scheduled for launch in 2011. This information will enable a greater understanding of the concentration and distribution of H 2 O and NH 3 in the Jovian atmosphere, which will reveal much about how Jupiter and our solar system formed and how similar planets could form in other solar systems, even planets that may be hospitable to life.

  11. Surface Penetrating Radar Simulations for Jupiter's Icy Moons

    Science.gov (United States)

    Markus, Thorsten; Gogineni, S. P.; Green, J. L.; Reinisch, B. W.; Song, P.; Fung, S. F.; Benson, R. F.; Taylor, W. W. L.; Cooper, F.

    2003-01-01

    The icy moons of Jupiter (Europa, Callisto, and Ganymede) are of similar overall composition but show different surface features as a result of different sub-surface processes. Furthermore, each of these moons could have a liquid ocean of water buried underneath the icy crust, but their depth can only be speculated. For Europa, estimates put the thickness of the ice shell anywhere between 2-30 km, with'a few models predicting up to 100 km. Much of the uncertainties are due to the largely unknown temperature gradients and levels of water impurities across different surface layers. One of the most important geological processes is the possible transportation of heat by ice convection. If the ice is convecting, then an upper limit of about 20 km is set for the depth of the ocean underneath. Convection leads to a sharp increase in temperature followed by a thick region of nearly constant temperature. If ice is not convecting, then an exponentially increasing temperature profile is expected. The crust is thought to be a mixture of ice and rock, and although the exact percentage of rock is not known, it is expected to be low. Additionally, the ice crust could contain salt, similar to sea ice on Earth. The exact amount of salt and how that amount changes with depth is also unknown. In preparation for the Jupiter Icy Moons Orbiter (JIMO) mission, we performed simulations for a surface-penetrating radar investigating signatures for different possible surface and sub-surface structures of these moons in order to estimate the applicability of using radar with a frequency range between 1 and 50 MHz. This includes simulations of power requirements, attenuation losses, layer resolutions for scenarios with and without the presence of a liquid ocean underneath the ice, cases of convecting and non-convecting ice, different impurities within the ice, and different surface roughnesses.

  12. Cloud structure and composition of Jupiter's troposphere from 5-{\\mu}m Cassini VIMS spectroscopy

    CERN Document Server

    Giles, Rohini S; Irwin, Patrick G J

    2015-01-01

    Jupiter's tropospheric composition and cloud structure are studied using Cassini VIMS 4.5-5.1 {\\mu}m thermal emission spectra from the 2000-2001 flyby. We make use of both nadir and limb darkening observations on the planet's nightside, and compare these with dayside observations. Although there is significant spatial variability in the 5-{\\mu}m brightness temperatures, the shape of the spectra remain very similar across the planet, suggesting the presence of a spectrally-flat, spatially inhomogeneous cloud deck. We find that a simple cloud model consisting of a single, compact cloud is able to reproduce both nightside and dayside spectra, subject to the following constraints: (i) the cloud base is located at pressures of 1.2 bar or lower; (ii) the cloud particles are highly scattering; (iii) the cloud is sufficiently spectrally flat. Using this cloud model, we search for global variability in the cloud opacity and the phosphine deep volume mixing ratio. We find that the vast majority of the 5-{\\mu}m inhomoge...

  13. A Principal Component Analysis of global images of Jupiter obtained by Cassini ISS

    Science.gov (United States)

    Ordóñez Etxeberria, I.; Hueso, R.; Sánchez-Lavega, A.

    2014-04-01

    The Cassini spacecraft flybied Jupiter in December 2000. The Imaging Science Subsystem (ISS) cameras acquired a large number of images at different spatial resolution in several filters sensitive to different altitudes and to cloud color. We have used these images to build high-resolution multi-wavelength nearly full maps of the planet in cylindrical and polar projections. The images have been analyzed by means of a principal component analysis technique (PCA) which looks for spatial covariances in different filtered images and proposes a new set of images (Principal Components, PC) which contains most of the spatial variability. The goal of this research is triple since we: 1) explore correlations between the ammonia cloud layer observed in most filters and the upper hazes observed in methane band images and UV, 2) we explore the spatial distribution of chromophores similarly to previous studies using HST images [1, 2]; 3) we look for image combinations that could be useful for cloud features sharpening. Furthermore, we study a global characterization of reletive altimetry of clouds and hazes from synthetic indexes between images with different contributions from the methane absorption bands (CB1, CB2, CB3, MT1, MT2, MT3).

  14. Understanding NEOs: The Role of Characterization Missions

    Science.gov (United States)

    Morrison, David

    2007-10-01

    NEOs are important from multiple perspectives, including science, hazard mitigation, space resources, and as targets for human missions. Much can be learned from ground-based studies, especially with radar, but the unique value of in situ investigation has been shown by missions such as NEAR-Shoemaker and Hayabusa to asteroids Eros and Itokawa, and Deep Impact and Stardust to comets. The next mission targets are likely to be NEAs in the subkilometer size range. Because these smaller objects are much more numerous, they are the objects we most need to understand from a defense perspective, and they are also the most likely targets for early human missions. However, there are unique challenges in sending spacecraft to investigate sub-km asteroids. Reconnaissance flybys are of little use, orbiting requires active control, and landing on such a low-gravity surface is perhaps better described as docking. Yet we need to operate close to the target, and probably to land, to obtain crucial information about interior structure. This paper deals primarily with small landers like the Near Earth Asteroid Trailblazer Mission (NEAT) studied at Ames Research Center. The NEAT objectives are to provide global reconnaissance (shape, mass, density, dynamical state), in situ surface characterization, and long-term precision tracking. Alternative approaches use deep-penetrating radar and electromagnetic sounding to probe interior structure. A third class of missions is ballistic impactors such as the ESA Don Quijote, which test one of the technologies for deflecting small asteroids. If the targets are selected for their accessibility, such missions could be implemented with low-cost launchers such as Pegasus, Falcon, or Minotaur. Such missions will have high science return. But from the perspective of defense, we have not yet developed a consensus strategy for the role of such characterization missions.

  15. Multi-Objective Hybrid Optimal Control for Interplanetary Mission Planning

    Science.gov (United States)

    Englander, Jacob

    2015-01-01

    Preliminary design of low-thrust interplanetary missions is a highly complex process. The mission designer must choose discrete parameters such as the number of flybys, the bodies at which those flybys are performed, and in some cases the final destination. Because low-thrust trajectory design is tightly coupled with systems design, power and propulsion characteristics must be chosen as well. In addition, a time-history of control variables must be chosen which defines the trajectory. There are often many thousands, if not millions, of possible trajectories to be evaluated. The customer who commissions a trajectory design is not usually interested in a point solution, but rather the exploration of the trade space of trajectories between several different objective functions. This can be very expensive process in terms of the number of human analyst hours required. An automated approach is therefore very desirable. This work presents such an approach by posing the mission design problem as a multi-objective hybrid optimal control problem. The methods is demonstrated on hypothetical mission to the main asteroid belt and to Deimos.

  16. MESSENGER, MErcury: Surface, Space ENvironment, GEochemistry, and Ranging; A Mission to Orbit and Explore the Planet Mercury

    Science.gov (United States)

    1999-01-01

    MESSENGER is a scientific mission to Mercury. Understanding this extraordinary planet and the forces that have shaped it is fundamental to understanding the processes that have governed the formation, evolution, and dynamics of the terrestrial planets. MESSENGER is a MErcury Surface, Space ENvironment, GEochemistry and Ranging mission to orbit Mercury for one Earth year after completing two flybys of that planet following two flybys of Venus. The necessary flybys return significant new data early in the mission, while the orbital phase, guided by the flyby data, enables a focused scientific investigation of this least-studied terrestrial planet. Answers to key questions about Mercury's high density, crustal composition and structure, volcanic history, core structure, magnetic field generation, polar deposits, exosphere, overall volatile inventory, and magnetosphere are provided by an optimized set of miniaturized space instruments. Our goal is to gain new insight into the formation and evolution of the solar system, including Earth. By traveling to the inner edge of the solar system and exploring a poorly known world, MESSENGER fulfills this quest.

  17. Definition of Saturn's magnetospheric model parameters for the Pioneer 11 flyby

    Directory of Open Access Journals (Sweden)

    E. S. Belenkaya

    2006-05-01

    Full Text Available This paper presents a description of a method for selection parameters for a global paraboloid model of Saturn's magnetosphere. The model is based on the preexisting paraboloid terrestrial and Jovian models of the magnetospheric field. Interaction of the solar wind with the magnetosphere, i.e. the magnetotail current system, and the magnetopause currents screening all magnetospheric field sources, is taken into account. The input model parameters are determined from observations of the Pioneer 11 inbound flyby.

  18. The Europa Ocean Discovery mission

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, B.C. [Los Alamos National Lab., NM (United States); Chyba, C.F. [Univ. of Arizona, Tucson, AZ (United States); Abshire, J.B. [National Aeronautics and Space Administration, Greenbelt, MD (United States). Goddard Space Flight Center] [and others

    1997-06-01

    Since it was first proposed that tidal heating of Europa by Jupiter might lead to liquid water oceans below Europa`s ice cover, there has been speculation over the possible exobiological implications of such an ocean. Liquid water is the essential ingredient for life as it is known, and the existence of a second water ocean in the Solar System would be of paramount importance for seeking the origin and existence of life beyond Earth. The authors present here a Discovery-class mission concept (Europa Ocean Discovery) to determine the existence of a liquid water ocean on Europa and to characterize Europa`s surface structure. The technical goal of the Europa Ocean Discovery mission is to study Europa with an orbiting spacecraft. This goal is challenging but entirely feasible within the Discovery envelope. There are four key challenges: entering Europan orbit, generating power, surviving long enough in the radiation environment to return valuable science, and complete the mission within the Discovery program`s launch vehicle and budget constraints. The authors will present here a viable mission that meets these challenges.

  19. Trajectory options for the DART mission

    Science.gov (United States)

    Atchison, Justin A.; Ozimek, Martin T.; Kantsiper, Brian L.; Cheng, Andrew F.

    2016-06-01

    This study presents interplanetary trajectory options for the Double Asteroid Redirection Test (DART) spacecraft to reach the near Earth object, Didymos binary system, during its 2022 Earth conjunction. DART represents a component of a joint NASA-ESA mission to study near Earth object kinetic impact deflection. The DART trajectory must satisfy mission objectives for arrival timing, geometry, and lighting while minimizing launch vehicle and spacecraft propellant requirements. Chemical propulsion trajectories are feasible from two candidate launch windows in late 2020 and 2021. The 2020 trajectories are highly perturbed by Earth's orbit, requiring post-launch deep space maneuvers to retarget the Didymos system. Within these windows, opportunities exist for flybys of additional near Earth objects: Orpheus in 2021 or 2007 YJ in 2022. A second impact attempt, in the event that the first impact is unsuccessful, can be added at the expense of a shorter launch window and increased (∼3x) spacecraft ΔV . However, the second impact arrival geometry has poor lighting, high Earth ranges, and would require additional degrees of freedom for solar panel and/or antenna gimbals. A low-thrust spacecraft configuration increases the trajectory flexibility. A solar electric propulsion spacecraft could be affordably launched as a secondary spacecraft in an Earth orbit and spiral out to target the requisite interplanetary departure condition. A sample solar electric trajectory was constructed from an Earth geostationary transfer using a representative 1.5 kW thruster. The trajectory requires 9 months to depart Earth's sphere of influence, after which its interplanetary trajectory includes a flyby of Orpheus and a second Didymos impact attempt. The solar electric spacecraft implementation would impose additional bus design constraints, including large solar arrays that could pose challenges for terminal guidance. On the basis of this study, there are many feasible options for DART to

  20. Cassini Maneuver Experience for the Fourth Year of the Solstice Mission

    Science.gov (United States)

    Vaquero, Mar; Hahn, Yungsun; Stumpf, Paul; Valerino, Powtawche; Wagner, Sean; Wong, Mau

    2014-01-01

    After sixteen years of successful mission operations and invaluable scientific discoveries, the Cassini orbiter continues to tour Saturn on the most complex gravity-assist trajectory ever flown. To ensure that the end-of-mission target of September 2017 is achieved, propellant preservation is highly prioritized over maneuver cycle minimization. Thus, the maneuver decision process, which includes determining whether a maneuver is performed or canceled, designing a targeting strategy and selecting the engine for execution, is being continuously re-evaluated. This paper summarizes the maneuver experience throughout the fourth year of the Solstice Mission highlighting 27 maneuvers targeted to nine Titan flybys.

  1. Surface of young Jupiter family comet 81P/Wild 2: view from the Stardust Spacecraft.

    Science.gov (United States)

    Brownlee, Donald E; Horz, Friedrich; Newburn, Ray L; Zolensky, Michael; Duxbury, Thomas C; Sandford, Scott; Sekanina, Zdenek; Tsou, Peter; Hanner, Martha S; Clark, Benton C; Green, Simon F; Kissel, Jochen

    2004-06-18

    Images taken by the Stardust mission during its flyby of 81P/Wild 2 show the comet to be a 5-kilometer oblate body covered with remarkable topographic features, including unusual circular features that appear to be impact craters. The presence of high-angle slopes shows that the surface is cohesive and self-supporting. The comet does not appear to be a rubble pile, and its rounded shape is not directly consistent with the comet being a fragment of a larger body. The surface is active and yet it retains ancient terrain. Wild 2 appears to be in the early stages of its degradation phase as a small volatile-rich body in the inner solar system.

  2. Warm Jupiters from Secular Planet–Planet Interactions

    Science.gov (United States)

    Petrovich, Cristobal; Tremaine, Scott

    2016-10-01

    Most warm Jupiters (gas-giant planets with 0.1 {{au}}≲ a≲ 1 au) have pericenter distances that are too large for significant orbital migration by tidal friction. We study the possibility that the warm Jupiters are undergoing secular eccentricity oscillations excited by an outer companion (a planet or star) in an eccentric and/or mutually inclined orbit. In this model, the warm Jupiters migrate periodically, in the high-eccentricity phase of the oscillation, but are typically observed at lower eccentricities. We show that in this model the steady-state eccentricity distribution of the warm Jupiters is approximately flat, which is consistent with the observed distribution if we restrict the sample to warm Jupiters with detected outer planetary companions. The eccentricity distribution of warm Jupiters without companions exhibits a peak at e≲ 0.2 that must be explained by a different formation mechanism. Based on a population synthesis study, we find that high-eccentricity migration excited by an outer planetary companion (1) can account for ∼ 20 % of the warm Jupiters and most of the warm Jupiters with e≳ 0.4; and (2) can produce most of the observed population of hot Jupiters, with a semimajor axis distribution that matches the observations, but fails to account adequately for ∼ 60 % of hot Jupiters with projected obliquities ≲ 20^\\circ . Thus ∼ 20 % of the warm Jupiters and ∼ 60 % of the hot Jupiters can be produced by high-eccentricity migration. We also provide predictions for the expected mutual inclinations and spin-orbit angles of the planetary systems with hot and warm Jupiters produced by high-eccentricity migration.

  3. An Impacting Descent Probe for Europa and the Other Galilean Moons of Jupiter

    Science.gov (United States)

    Wurz, P.; Lasi, D.; Thomas, N.; Piazza, D.; Galli, A.; Jutzi, M.; Barabash, S.; Wieser, M.; Magnes, W.; Lammer, H.; Auster, U.; Gurvits, L. I.; Hajdas, W.

    2017-08-01

    We present a study of an impacting descent probe that increases the science return of spacecraft orbiting or passing an atmosphere-less planetary bodies of the solar system, such as the Galilean moons of Jupiter. The descent probe is a carry-on small spacecraft (fast ( km/s) descent to the surface until impact. The science goals and the concept of operation are discussed with particular reference to Europa, including options for flying through water plumes and after-impact retrieval of very-low altitude science data. All in all, it is demonstrated how the descent probe has the potential to provide a high science return to a mission at a low extra level of complexity, engineering effort, and risk. This study builds upon earlier studies for a Callisto Descent Probe for the former Europa-Jupiter System Mission of ESA and NASA, and extends them with a detailed assessment of a descent probe designed to be an additional science payload for the NASA Europa Mission.

  4. Jumping Jupiter can explain Mercury's orbit

    CERN Document Server

    Roig, Fernando; DeSouza, Sandro Ricardo

    2016-01-01

    The orbit of Mercury has large values of eccentricity and inclination that cannot be easily explained if this planet formed on a circular and coplanar orbit. Here, we study the evolution of Mercury's orbit during the instability related to the migration of the giant planets in the framework of the jumping Jupiter model. We found that some instability models are able to produce the correct values of Mercury's eccentricity and inclination, provided that relativistic effects are included in the precession of Mercury's perihelion. The orbital excitation is driven by the fast change of the normal oscillation modes of the system corresponding to the perihelion precession of Jupiter (for the eccentricity), and the nodal regression of Uranus (for the inclination).

  5. The Escaping Upper Atmospheres of Hot Jupiters

    Science.gov (United States)

    Davidson, Eric; Jones, Gabrielle; Uribe, Ana; Carson, Joseph

    2017-01-01

    Hot Jupiters are massive gaseous planets which orbit closely to their parent star. The strong stellar irradiation at these small orbital separations causes the temperature of the upper atmosphere of the planet to rise. This can cause the planet's atmosphere to escape into space, creating an exoplanet outflow. We ascertained which factors determine the presence and structure of these outflows by creating one dimensional simulations of the density, pressure, velocity, optical depth, and neutral fraction of hot Jupiter atmospheres. This was done for planets of masses and radii ranging from 0.5-1.5 Mj and 0.5-1.5 Rj. We found the outflow rate to be highest for a planet of 0.5 Mj and 1.5 Rj at 5.3×10-14 Mj/Yr. We also found that the higher the escape velocity, the lower the chance of the planet having an outflow.

  6. Measurement of the radius of Mercury by radio occultation during the MESSENGER flybys

    Science.gov (United States)

    Perry, Mark E.; Kahan, Daniel S.; Barnouin, Olivier S.; Ernst, Carolyn M.; Solomon, Sean C.; Zuber, Maria T.; Smith, David E.; Phillips, Roger J.; Srinivasan, Dipak K.; Oberst, Jürgen; Asmar, Sami W.

    2011-12-01

    The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft completed three flybys of Mercury in 2008-2009. During the first and third of those flybys, MESSENGER passed behind the planet from the perspective of Earth, occulting the radio-frequency (RF) transmissions. The occultation start and end times, recovered with 0.1 s accuracy or better by fitting edge-diffraction patterns to the RF power history, are used to estimate Mercury's radius at the tangent point of the RF path. To relate the measured radius to the planet shape, we evaluate local topography using images to identify the high-elevation feature that defines the RF path or using altimeter data to quantify surface roughness. Radius measurements are accurate to 150 m, and uncertainty in the average radius of the surrounding terrain, after adjustments are made from the local high at the tangent point of the RF path, is 350 m. The results are consistent with Mercury's equatorial shape as inferred from observations by the Mercury Laser Altimeter and ground-based radar. The three independent estimates of radius from occultation events collectively yield a mean radius for Mercury of 2439.2±0.5 km.

  7. Thermal Emission Photometry of Deep Impact Flyby Target (163249) 2002 GT

    Science.gov (United States)

    Lim, Lucy F.; Moskovitz, N. A.; Licandro, J.; Emery, J. P.; Reddy, V.; Vilas, F.; 2002 GT Observing Team

    2013-10-01

    Near-Earth asteroid (163249) 2002 GT is now the target of a Deep Impact spacecraft flyby in Jan. 2020 (see Pittichova et al., this volume, for details of the flyby and observing campaign). Thermal emission photometry of 2002 GT was obtained from NIRI on Gemini-North in the L' and M' filters, which are centered at 3.76 and 4.68 microns respectively. J- and K-band reflectance photometry was also acquired in support of the thermal observations. The full JKL'M' set was acquired on UT 2013-Jun-13 at a solar phase angle of 53 degrees. A further set of photometry in J, K, and L' only was carried out on 2013-Jun-19 at a phase angle of 65 degrees. High water vapor conditions at Mauna Kea during this period unfortunately prevented acquisition of a second set of M' measurements. In addition, N-band photometry of 2002 GT was conducted on 2013-Jun-10 from CanariCam at the 10-meter Gran Telescopio Canarias using a beta version of the moving object guiding system. Data were acquired in three filters between 8.7 and 12.5 microns, although the limitations of the guiding are complicating the analysis. (We note that N-band observing was not offered by either Gemini or IRTF during this apparition.) Data analysis is ongoing and results will be discussed. We appreciate the efforts of the Gemini and GTC staff in support of these observing programs.

  8. Radioisotope Thermophotovoltaic (RTPV) Generator and Its Applicability to an Illustrative Space Mission

    Energy Technology Data Exchange (ETDEWEB)

    Schock, A.; Mukunda, M.; Or, T.; Kumar, V.; Summers, G.

    1994-02-14

    The paper describes the results of a DOE-sponsored design study of a radioisotope thermophotovoltaic generator (RTPV), to complement similar studies of Radioisotope Thermoelectric Generators (RTGs) and Stirling Generators (RSGs) previously published by the author. Instead of conducting a generic study, it was decided to focus the design effort by directing it at a specific illustrative space mission, Pluto Fast Flyby (PFF). That mission, under study by JPL, envisages a direct eight-year flight to Pluto (the only unexplored planet in the solar system), followed by comprehensive mapping, surface composition, and atmospheric structure measurements during a brief flyby of the planet and its moon Charon, and transmission of the recorded science data to Earth during a post-encounter cruise lasting up to one year.

  9. Secular orbital evolution of Jupiter family comets

    Science.gov (United States)

    Rickman, H.; Gabryszewski, R.; Wajer, P.; Wiśniowski, T.; Wójcikowski, K.; Szutowicz, S.; Valsecchi, G. B.; Morbidelli, A.

    2017-02-01

    Context. The issue of the long term dynamics of Jupiter family comets (JFCs) involves uncertain assumptions about the physical evolution and lifetimes of these comets. Contrary to what is often assumed, real effects of secular dynamics cannot be excluded and therefore merit investigation. Aims: We use a random sample of late heavy bombardment cometary projectiles to study the long-term dynamics of JFCs by a Monte Carlo approach. In a steady-state picture of the Jupiter family, we investigate the orbital distribution of JFCs, including rarely visited domains like retrograde orbits or orbits within the outer parts of the asteroid main belt. Methods: We integrate 100 000 objects over a maximum of 100 000 orbital revolutions including the Sun, a comet, and four giant planets. Considering the steady-state number of JFCs to be proportional to the total time spent in the respective orbital domain, we derive the capture rate based on observed JFCs with small perihelia and large nuclei. We consider a purely dynamical model and one where the nuclei are eroded by ice sublimation. Results: The JFC inclination distribution is incompatible with our erosional model. This may imply that a new type of comet evolution model is necessary. Considering that comets may live for a long time, we show that JFCs can evolve into retrograde orbits as well as asteroidal orbits in the outer main belt or Cybele regions. The steady-state capture rate into the Jupiter family is consistent with 1 × 109 scattered disk objects with diameters D > 2 km. Conclusions: Our excited scattered disk makes it difficult to explain the JFC inclination distribution, unless the physical evolution of JFCs is more intricate than assumed in standard, erosional models. Independent of this, the population size of the Jupiter family is consistent with a relatively low-mass scattered disk.

  10. Modelling of Jupiter's Innermost Radiation Belt

    Science.gov (United States)

    Mihalov, J. D.; DeVincenzi, Donald (Technical Monitor)

    1999-01-01

    In order to understand better source and loss processes for energetic trapped protons near Jupiter, a modification of de Pater and Goertz' finite difference diffusion calculations for Jovian equatorial energetic electrons is made to apply to the case of protons inside the orbit of Metis. Explicit account is taken of energy loss in the Jovian ring. Comparison of the results is made with Galileo Probe measurements.

  11. DIRECTLY IMAGING TIDALLY POWERED MIGRATING JUPITERS

    Energy Technology Data Exchange (ETDEWEB)

    Dong Subo; Katz, Boaz; Socrates, Aristotle [Institute for Advanced Study, Princeton, NJ 08540 (United States)

    2013-01-10

    Upcoming direct-imaging experiments may detect a new class of long-period, highly luminous, tidally powered extrasolar gas giants. Even though they are hosted by {approx} Gyr-'old' main-sequence stars, they can be as 'hot' as young Jupiters at {approx}100 Myr, the prime targets of direct-imaging surveys. They are on years-long orbits and presently migrating to 'feed' the 'hot Jupiters'. They are expected from 'high-e' migration mechanisms, in which Jupiters are excited to highly eccentric orbits and then shrink semimajor axis by a factor of {approx}10-100 due to tidal dissipation at close periastron passages. The dissipated orbital energy is converted to heat, and if it is deposited deep enough into the atmosphere, the planet likely radiates steadily at luminosity L {approx} 100-1000 L{sub Jup}(2 Multiplication-Sign 10{sup -7}-2 Multiplication-Sign 10{sup -6} L{sub Sun }) during a typical {approx} Gyr migration timescale. Their large orbital separations and expected high planet-to-star flux ratios in IR make them potentially accessible to high-contrast imaging instruments on 10 m class telescopes. {approx}10 such planets are expected to exist around FGK dwarfs within {approx}50 pc. Long-period radial velocity planets are viable candidates, and the highly eccentric planet HD 20782b at maximum angular separation {approx}0.''08 is a promising candidate. Directly imaging these tidally powered Jupiters would enable a direct test of high-e migration mechanisms. Once detected, the luminosity would provide a direct measurement of the migration rate, and together with mass (and possibly radius) estimate, they would serve as a laboratory to study planetary spectral formation and tidal physics.

  12. Preliminary Results on HAT-P-4, TrES-3, XO-2, and GJ 436 from the NASA EPOXI Mission

    CERN Document Server

    Ballard, Sarah; A'Hearn, Michael F; Deming, Drake; Holman, Matthew J; Christiansen, Jessie L; Weldrake, David T F; Barry, Richard K; Kuchner, Marc J; Livengood, Timothy A; Pedelty, Jeffrey; Schultz, Alfred; Hewagama, Tilak; Sunshine, Jessica M; Wellnitz, Dennis D; Hampton, Don L; Lisse, Carey M; Seager, Sara; Veverka, Joseph F

    2008-01-01

    EPOXI (EPOCh + DIXI) is a NASA Discovery Program Mission of Opportunity using the Deep Impact flyby spacecraft. The EPOCh (Extrasolar Planet Observation and Characterization) Science Investigation will gather photometric time series of known transiting exoplanet systems from January through August 2008. Here we describe the steps in the photometric extraction of the time series and present preliminary results of the first four EPOCh targets.

  13. A survey of solar wind conditions at 5 AU: A tool for interpreting solar wind-magnetosphere interactions at Jupiter

    Directory of Open Access Journals (Sweden)

    Robert Wilkes Ebert

    2014-09-01

    Full Text Available We examine Ulysses solar wind and interplanetary magnetic field (IMF observations at 5 AU for two ~13 month intervals during the rising and declining phases of solar cycle 23 and the predicted response of the Jovian magnetosphere during these times. The declining phase solar wind, composed primarily of corotating interaction regions and high-speed streams, was, on average, faster, hotter, less dense, and more Alfvénic relative to the rising phase solar wind, composed mainly of slow wind and interplanetary coronal mass ejections. Interestingly, none of solar wind and IMF distributions reported here were bimodal, a feature used to explain the bimodal distribution of bow shock and magnetopause standoff distances observed at Jupiter. Instead, many of these distributions had extended, non-Gaussian tails that resulted in large standard deviations and much larger mean over median values. The distribution of predicted Jupiter bow shock and magnetopause standoff distances during these intervals were also not bimodal, the mean/median values being larger during the declining phase by ~1 – 4%. These results provide data-derived solar wind and IMF boundary conditions at 5 AU for models aimed at studying solar wind-magnetosphere interactions at Jupiter and can support the science investigations of upcoming Jupiter system missions. Here, we provide expectations for Juno, which is scheduled to arrive at Jupiter in July 2016. Accounting for the long-term decline in solar wind dynamic pressure reported by McComas et al. (2013, Jupiter’s bow shock and magnetopause is expected to be at least 8 – 12% further from Jupiter, if these trends continue.

  14. Hubble Gallery of Jupiter's Galilean Satellites

    Science.gov (United States)

    1995-01-01

    This is a Hubble Space Telescope 'family portrait' of the four largest moons of Jupiter, first observed by the Italian scientist Galileo Galilei nearly four centuries ago. Located approximately one-half billion miles away, the moons are so small that, in visible light, they appear as fuzzy disks in the largest ground-based telescopes. Hubble can resolve surface details seen previously only by the Voyager spacecraft in the early 1980s. While the Voyagers provided close-up snapshots of the satellites, Hubble can now follow changes on the moons and reveal other characteristics at ultraviolet and near-infrared wavelengths.Over the past year Hubble has charted new volcanic activity on Io's active surface, found a faint oxygen atmosphere on the moon Europa, and identified ozone on the surface of Ganymede. Hubble ultraviolet observations of Callisto show the presence of fresh ice on the surface that may indicate impacts from micrometeorites and charged particles from Jupiter's magnetosphere.Hubble observations will play a complementary role when the Galileo spacecraft arrives at Jupiter in December of this year.This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/

  15. Capture of irregular satellites at Jupiter

    Energy Technology Data Exchange (ETDEWEB)

    Nesvorný, David; Vokrouhlický, David; Deienno, Rogerio [Department of Space Studies, Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States)

    2014-03-20

    The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early solar system instability when encounters between the outer planets occurred. Nesvorný et al. already showed that the irregular satellites of Saturn, Uranus, and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary disk is found to be (1.3-3.6) × 10{sup –8}. This is roughly enough to explain the observed population of jovian irregular moons. We also confirm Nesvorný et al.'s results for the irregular satellites of Saturn, Uranus, and Neptune.

  16. Structures of the Planets Jupiter and Saturn

    CERN Document Server

    Kerley, Gerald I

    2013-01-01

    New equations of state (EOS) for hydrogen, helium, and compounds containing heavier elements are used to construct models for the structures of the planets Jupiter and Saturn. Good agreement with the gravitational moments J2 and J4 is obtained with a model that uses a two-layer gas envelope, in which the inner region is denser than the outer one, together with a small, dense core. It is possible to match J2 with a homogeneous envelope, but an envelope with a denser inner region is needed to match both moments. The two-layer envelope also gives good agreement with the global oscillation data for Jupiter. In Jupiter, the boundary between the inner and outer envelopes occurs at 319 GPa, with an 8% density increase. In Saturn, it occurs at 227 GPa, with a 69% density increase. The differences between the two planets show that the need for a density increase is not due to EOS errors. It is also shown that helium enrichment cannot be the cause of the density increase. The phenomenon can be explained as the result o...

  17. Directly Imaging Tidally Powered Migrating Jupiters

    CERN Document Server

    Dong, Subo; Socrates, Aristotle

    2012-01-01

    We show that ongoing direct imaging experiments may detect a new class of long-period, highly luminous, tidally powered extrasolar gas giants. Even though they are hosted by Gyr-"old" main-sequence stars, they can be as "hot" as young Jupiters at ~100 Myr, the prime targets of direct imaging surveys. These planets, with years-long orbits, are presently migrating to "feed" the "hot Jupiters" in steady state. Their existence is expected from a class of "high-e" migration mechanisms, in which gas giants are excited to highly eccentric orbits and then shrink their semi-major axis by factor of ~ 10-100 due to tidal dissipation at successive close periastron passages. The dissipated orbital energy is converted to heat, and if it is deposited deep enough into the planet atmosphere, the planet likely radiates steadily at luminosity ~2-3 orders of magnitude larger than that of our Jupiter during a typical Gyr migration time scale. Their large orbital separations and expected high planet-to-star flux ratios in IR make ...

  18. Illuminating Hot Jupiters in caustic crossing

    CERN Document Server

    Sajadian, Sedighe

    2010-01-01

    In recent years a large number of Hot Jupiters orbiting in a very close orbit around the parent stars have been explored with the transit and doppler effect methods. Here in this work we study the gravitational microlensing effect of a binary lens on a parent star with a Hot Jupiter revolving around it. Caustic crossing of the planet makes enhancements on the light curve of the parent star in which the signature of the planet can be detected by high precision photometric observations. We use the inverse ray shooting method with tree code algorithm to generate the combined light curve of the parent star and the planet. In order to investigate the probability of observing the planet signal, we do a Monte-Carlo simulation and obtain the observational optical depth of $\\tau \\sim 10^{-8}$. We show that about ten years observations of Galactic Bulge with a network of telescopes will enable us detecting about ten Hot Jupiter with this method. Finally we show that the observation of the microlensing event in infra-re...

  19. Absorption of trapped particles by Jupiter's moons

    Science.gov (United States)

    Hess, W. N.; Birmingham, T. J.; Mead, G. D.

    1974-01-01

    Inclusion of absorption effects of the four innermost moons in the radial transport equations for electrons and protons in Jupiter's magnetosphere. It is found that the phase space density n at 2 Jupiter radii for electrons with equatorial pitch angles less than 69 deg is reduced by a factor of 42,000 when lunar absorption is included in the calculation. For protons with equatorial pitch angles less than 69 deg the corresponding reduction factor is 2,300,000. The effect of the satellites becomes progressively weaker for both electrons and protons as equatorial pitch angles of 90 deg are approached, because the likelihood of impacting a satellite becomes progressively smaller. The large density decreases found at the orbits of Io, Europa, and Ganymede result in corresponding particle flux decreases that should be observed by spacecraft making particle measurements in Jupiter's magnetosphere. The characteristic signature of satellite absorption should be a downward-pointing vertex in the flux versus radius curve at the L value corresponding to each satellite.

  20. Modeling the Neutral Gas and Plasma Environment of Jupiter's Moon Europa

    Science.gov (United States)

    Rubin, Martin; Tenishev, Valeriy; Hansen, Kenneth; Jia, Xianzhe; Combi, Michael; Gombosi, Tamas

    Jupiter's moon Europa has a thin gravitationally bound neutral atmosphere, which is mostly created through sputtering of high-energy ions impacting on its icy surface. The interaction of Europa with the Jovian magnetosphere is simulated using the magnetohydrodynamics (MHD) model BATSRUS. We start from the model by Kabin et al. [JGR, Vol. 104, No. A9, (1999)], which accounts for the exospheric mass loading, ion-neutral charge exchange, and ion-electron recombination. The derived magnetic field topology and plasma speeds are used to calculate the Lorentz force for our test particle Monte Carlo model. We use this model to simulate Europa's plasma and neutral environment by tracking particles created on the moon's surface by sputtering or sublimation, through dissociation and/or ionization in the atmosphere, or entering the system from Jupiter's magnetosphere as high energy ions. Neutral particle trajectories are followed by solving the equation of motion in Europa's gravity field whereas the ion population is additionally subject to the Lorentz force. We will show preliminary results of this work with application to the missions to the Jupiter system currently under consideration by NASA (JEO) and ESA (JGO).

  1. The asteroid belt outer region under jumping-Jupiter migration

    Science.gov (United States)

    Gaspar, H. S.; Winter, O. C.; Vieira Neto, E.

    2017-09-01

    The radial configuration of the outer region of the main asteroid belt is quite peculiar, and has much to say about the past evolution of Jupiter. In this work, we investigate the dynamical effects of a jumping-Jupiter-like migration over a more extended primordial asteroid belt. Jupiter's migrations are simulated using a fast jumping-Jupiter synthesizer. Among the results, we highlight non-negligible fractions of primordial objects trapped in 3:2 and 4:3 mean motion resonances (MMRs) with Jupiter. They survived the whole truculent phase of migration and originated populations that are like Hildas and Thules. Fractions ranging from 3 to 6 per cent of the initial distribution remained trapped in 3:2 MMR, and at least 0.05 per cent in 4:3. These results show that the resonance trapping of primordial objects may have originated these resonant populations. This theory is consistent even for Jupiter's truculent evolution.

  2. The Radar for Icy Moon Exploration (RIME) on the JUICE Mission

    Science.gov (United States)

    Bruzzone, L.; Plaut, J.; Alberti, G.; Blankenship, D. D.; Bovolo, F.; Campbell, B. A.; Castelletti, D.; Gim, Y.; Ilisei, A. M.; Kofman, W. W.; Komatsu, G.; McKinnon, W. B.; Mitri, G.; Moussessian, A.; Notarnicola, C.; Orosei, R.; Patterson, G. W.; Pettinelli, E.; Plettemeier, D.

    2015-12-01

    The Radar for Icy Moon Exploration (RIME) is one of the main instruments included in the JUpiter ICy moons Explorer (JUICE) ESA mission. It is a radar sounder designed for studying the subsurface geology and geophysics of Galilean icy moons (i.e., Ganymede, Europa and Callisto) and for detecting possible subsurface water. RIME is designed for penetration of the icy moons up to a depth of 9 km. Two main operation scenarios are foreseen for RIME: i) flyby observations of Europa, Ganymede and Callisto (from a distance of 1000 km to the closest approach of about 400 km); and ii) circular orbital observations around Ganymede at 500 km of altitude. According to these scenarios, RIME is designed to explore the icy shell of the Galilean icy satellites by characterizing the wide range of compositional, thermal, and structural variation found in the subsurface of these moons. RIME observations will profile the ice shells of the Galilean icy satellites with specific focus on Ganymede given the circular orbital phase. The acquired measures will provide geological context on hemispheric (thousands of km), regional (hundreds of km with multiple overlaps), and targeted (tens of km) scales appropriate for a variety of hypothesis tests. RIME will operate in a single frequency band, centred at 9 MHz. The frequency was selected as the result of extensive study of penetration capabilities, surface roughness of the moons, Jovian radio noise, antenna accommodation, and system design. The 9 MHz frequency provides penetration capabilities and mitigation of surface scattering (which can cause signal loss and clutter issues), at the expense of mapping coverage, as it is likely to obtain high SNR observations only on the anti-Jovian side of the target moons. The RIME antenna is a 16 m dipole. The chirp pulse bandwidth is up to 3 MHz, which provides vertical resolution of about 50 m in ice after side lobe weighting. RIME will also operate with 1 MHz bandwidth to reduce data volume when

  3. High-Power Radar Sounders for the Investigation of Jupiter Icy Moons

    Science.gov (United States)

    Safaeinili, A.; Ostro, S.; Rodriquez, E.; Blankenship, D.; Kurth, W.; Kirchner, D.

    2005-01-01

    The high power and high data rate capability made available by a Prometheus class spacecraft could significantly enhance our ability to probe the subsurface of the planets/moons and asteroid/comets. The main technology development driver for our radar is the proposed Jupiter Icy Moon Orbiter (or JIMO) mission due to its harsh radiation environment. We plan to develop a dual-band radar at 5 and 50 MHz in response to the two major science requirements identified by the JIMO Science Definition Team: studying the near subsurface (less than 2 km) at high resolution and detection of the ice/ocean interface for Europa (depth up to 30 km). The 50-MHz band is necessary to provide high spatial resolution (footprint and depth) as required by the JIMO mission science requirements as currently defined. Our preliminary assessment indicates that the 50-MHz system is not required to be as high-power as the 5-MHz system since it will be more limited by the surface clutter than the Jupiter or galactic background noise. The low frequency band (e.g. 5 MHz), which is the focus of this effort, would be necessary to mitigate the performance risks posed by the unknown subsurface structure both in terms of unknown attenuation due to volumetric scattering and also the detection of the interface through the attenuative transition region at the ice/ocean interface. Additionally, the 5-MHz band is less affected by the surface roughness that can cause loss of coherence and clutter noise. However, since the Signal-to-Noise-Ratio (SNR) of the 5-MHz radar band is reduced due to Jupiter noise when operating in the Jupiter side of the moon, it is necessary to increase the radiated power. Our challenge is to design a high-power HF radar that can hnction in Jupiter's high radiation environment, yet be able to fit into spacecraft resource constraints such as mass and thermal limits. Our effort to develop the JIMO radar sounder will rely on our team's experience with planetary radar sounder design

  4. Trajectory Dispersion Control for the Cassini Grand Finale Mission

    Science.gov (United States)

    Wong, Mau; Hahn, Yungsun; Roth, Duane; Vaquero, Mar

    2015-01-01

    The Cassini Grand Finale Mission, which consists of 22 ballistic orbits, will begin on April 22, 2017 after the last targeted Titan flyby. It will end on September 15, 2017 when the spacecraft dives into Saturn's atmosphere and be permanently captured. High volumes of unique science data from various onboard instruments are expected from the mission. To ensure its success and facilitate science planning, the trajectory dispersion needs to be controlled below 250 km (root-mean-square spatial deviation at the 68th percentile level) for a few segments of trajectory in the mission. This paper reports the formulation and solution of this dispersion control problem. We consider various sources of uncertainties including flyby error, orbit determination error, maneuver execution error, thruster firing control error, and uncertainty in Saturn's atmospheric model. A non-linear Monte Carlo Trajectory Dispersion tool is developed and employed for the analysis. It is found that a total of three Orbit Trim Maneuvers with a 99% (Delta)V usage of less than 2 m/s will adequately control the trajectory.

  5. The Role of Solar Neutrinos in the Jupiter

    CERN Document Server

    Burov, Valery

    2008-01-01

    Judging from the fact that the planet Jupiter is bigger in size than the Earth by 10^3 while is smaller than the Sun by 10^3 and that the average distance of the Jupiter from the Sun is 5.203 a.u., the solar neutrinos, when encounter the Jupiter, may have some accumulating effects bigger than on the Earth. We begin by estimating how much energy/power carried by solar neutrinos get transferred by this unique process, to confirm that solar neutrinos, despite of their feeble neutral weak current interactions, might deposit enough energy in the Jupiter. We also speculate on the other remarkable effects.

  6. High Power MPD Nuclear Electric Propulsion (NEP) for Artificial Gravity HOPE Missions to Callisto

    Science.gov (United States)

    McGuire, Melissa L.; Borowski, Stanley K.; Mason, Lee M.; Gilland, James

    2003-01-01

    This documents the results of a one-year multi-center NASA study on the prospect of sending humans to Jupiter's moon, Callisto, using an all Nuclear Electric Propulsion (NEP) space transportation system architecture with magnetoplasmadynamic (MPD) thrusters. The fission reactor system utilizes high temperature uranium dioxide (UO2) in tungsten (W) metal matrix cermet fuel and electricity is generated using advanced dynamic Brayton power conversion technology. The mission timeframe assumes on-going human Moon and Mars missions and existing space infrastructure to support launch of cargo and crewed spacecraft to Jupiter in 2041 and 2045, respectively.

  7. Tvashtar's Plume during the New Horizons Flyby of the Jovian System

    Science.gov (United States)

    Trafton, Laurence M.; Hoey, William Andrew; Ackley, Peter; Goldstein, David B.; Varghese, Philip L.

    2016-10-01

    During the gravity-assist flyby of the Jovian system from 26 Feb 2007 to 3 Mar 2007, the New Horizons spacecraft obtained multiple images of Io's Pele-class plume "Tvashtar" using the panchromatic LORRI camera, including a unique "movie" sequence of 5 images taken 2 minutes apart that provide the only record of dynamical activity for an extra-terrestrial volcanic plume. Prominent plume activity included a single traveling wave traveling down the west side of the canopy and a semi-regular particulate pattern that evolved down the canopy. The spout was detected in an average of the 5 movie images and its intensity may constrain the refractory complement of the plume. Comparison with the observed plume irradiance may then constrain the condensate complement. Other features, more apparent after subtracting the mean movie image, include semi-periodic azimuthal density variation in the canopy at plausibly common flight times from the vent, implying an azimuthal component to the dust density distribution at the vent. There are features that show a few large tendrils distributed in azimuth around the canopy that extend all the way to the surface, like the canopy projection, while the rest of the canopy appears to have a large discontinuity in density at the rim, as if the canopy were suspended. Successive waves having contrasting mean wavefront density suggest a fundamental-mode temporal pulsing at the vent. The scattering phase function for the plume particulates was found to be strongly forward scattering, increasing nearly monotonically during the flyby by an order of magnitude over the solar phase angle range 57 - 150 deg. Rathbun et al. (2014; Icarus 231, 261) reported that neither the Girru nor Tvashtar surface eruptions varied dramatically over 1-2 Mar 2007; however, most of the growth we found in Tvashtar's brightness during the flyby occurred by these dates. Therefore, increasing eruption activity, rising refractory dust density, or condensation may have

  8. Resolved Ultraviolet Reflectance Spectra of Mercury from the Third MESSENGER Flyby

    Science.gov (United States)

    Holsclaw, G. M.; McClintock, W. E.; Blewett, D. T.; Denevi, B. W.; Domingue, D. L.; Izenberg, N. R.; Jensen, E. A.; Robinson, M. S.; Solomon, S. C.; Sprague, A. L.; Vilas, F.

    2009-12-01

    Reflectance spectroscopy at ultraviolet wavelengths is a valuable remote sensing tool for studying the chemical makeup of planetary surfaces. The MESSENGER spacecraft instrument payload includes the Mercury Atmospheric and Surface Composition Spectrometer (MASCS), which contains the Ultraviolet and Visible Spectrometer (UVVS), capable of acquiring point-reflectance spectra from the far to near ultraviolet (115-350 nm). The first disk-integrated reflectance spectrum of Mercury at middle-ultraviolet wavelengths (220-300 nm) was obtained by MASCS-UVVS during the first flyby of the planet on 14 January 2008. A comparison of this spectrum with the reflectance of the Moon obtained with the same instrument showed that an inflection, interpreted as a volume absorption due to an electronic charge-transfer between oxygen and a transition-metal cation, was present in the Mercury data but absent in the lunar spectrum. Given the intense space weathering environment at Mercury, it was expected that such volume absorptions might be obscured by even small amounts of nanophase metallic iron within vapor-deposited coatings. During the second Mercury flyby on 6 October 2008, several spatially resolved middle-ultraviolet spectra were acquired. These spectra were found to have spectral characteristics similar to those of the disk-integrated spectrum. However, it was not possible to discern subtle spectral variations because of the spatial-spectral coupling of the data. The UVVS operates as a scanning-grating monochromator. Consequently, during acquisition of a spectrum (obtained one wavelength at a time) the instrument field of view is carried across the planet’s surface by spacecraft motion. Therefore, variations in albedo, composition, maturity, topography, and shadowing all contribute to structure in the spectrum. During MESSENGER’s third flyby of Mercury on 29 September 2009, a specialized observing strategy was implemented. From multispectral images obtained during the

  9. Galileo In-Situ Dust Measurements in Jupiter's Gossamer Rings

    CERN Document Server

    Krueger, Harald; Moissl, Richard; Gruen, Eberhard

    2008-01-01

    During its late orbital mission at Jupiter the Galileo spacecraft made two passages through the giant planet's gossamer ring system. The impact-ionization dust detector on board successfully recorded dust impacts during both ring passages and provided the first in-situ measurements from a dusty planetary ring. In all, a few thousand dust impacts were counted with the instrument accumulators during both ring passages, but only a total of 110 complete data sets of dust impacts were transmitted to Earth. Detected particle sizes range from about 0.2 to 5 micron, extending the known size distribution by an order of magnitude towards smaller particles than previously derived from optical imaging (Showalter et al. 2008). The grain size distribution increases towards smaller particles and shows an excess of these tiny motes in the Amalthea gossamer ring compared to the Thebe ring. The size distribution for the Amalthea ring derived from our in-situ measurements for the small grains agrees very well with the one obtai...

  10. Jupiter Observation Campaign: Citizen Science at the Outer Planets

    Science.gov (United States)

    Jones, J. Houston.; Wessen, A.; Pappalardo, Robert; Perry, Jason, Vance, Steve; Beisser, Kerri; Dyches, Preston

    2010-12-01

    NASA Solar System Education and Public Outreach (E/PO) will coordinate and disseminate a consistent process for receiving Jupiter observation data from citizen scientists. This may include a public repository or network matching scientists with citizen scientists who want to provide needed observations in a standard and consistent format. This will be a good Outer Planet mission contribution to the science community. Solar System Thematic E/PO will design a repository, or connect people with a process, and manage the process of defining the formatting and other needs of the data contributions from: 1) Regular observers: who right now do not have a consistent imaging of photography process or file naming convention for their data, etc. 2) Experienced observers, who currently send data on occasion to a network which includes appreciative scientists. record the start and end times of video they view each night, 3) Regional associations (ALPO, ALPO-Japan, BAA etc.) might be able to collect this info, disseminate the ground rules, etc.

  11. Validation of a Low-Thrust Mission Design Tool Using Operational Navigation Software

    Science.gov (United States)

    Englander, Jacob A.; Knittel, Jeremy M.; Williams, Ken; Stanbridge, Dale; Ellison, Donald H.

    2017-01-01

    Design of flight trajectories for missions employing solar electric propulsion requires a suitably high-fidelity design tool. In this work, the Evolutionary Mission Trajectory Generator (EMTG) is presented as a medium-high fidelity design tool that is suitable for mission proposals. EMTG is validated against the high-heritage deep-space navigation tool MIRAGE, demonstrating both the accuracy of EMTG's model and an operational mission design and navigation procedure using both tools. The validation is performed using a benchmark mission to the Jupiter Trojans.

  12. High precision comet trajectory estimates: the Mars flyby of C/2013 A1 (Siding Spring)

    CERN Document Server

    Farnocchia, D; Micheli, M; Delamere, A; Heyd, R S; Tholen, D J; Giorgini, J D; Owen, W M; Tamppari, L K

    2015-01-01

    The Mars flyby of C/2013 A1 (Siding Spring) represented a unique opportunity for imaging a long-period comet and resolving its nucleus and rotation period. Because of the small encounter distance and the high relative velocity, the goal of successfully observing C/2013 A1 from the Mars orbiting spacecrafts posed strict accuracy requirements on the comet's ephemerides. These requirements were hard to meet, as comets are known for being highly unpredictable: astrometric observations can be significantly biased and nongravitational perturbations affect comet trajectories. Therefore, even prior to the encounter, we remeasured a couple of hundred astrometric images obtained with ground-based and Earth-orbiting telescopes. We also observed the comet with the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (HiRISE) camera on 2014 October 7. In particular, these HiRISE observations were decisive in securing the trajectory and revealed that out-of-plane nongravitational perturbations were larg...

  13. Return to Mercury: a global perspective on MESSENGER's first Mercury flyby.

    Science.gov (United States)

    Solomon, Sean C; McNutt, Ralph L; Watters, Thomas R; Lawrence, David J; Feldman, William C; Head, James W; Krimigis, Stamatios M; Murchie, Scott L; Phillips, Roger J; Slavin, James A; Zuber, Maria T

    2008-07-04

    In January 2008, the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft became the first probe to fly past the planet Mercury in 33 years. The encounter revealed that Mercury is a dynamic system; its liquid iron-rich outer core is coupled through a dominantly dipolar magnetic field to the surface, exosphere, and magnetosphere, all of which interact with the solar wind. MESSENGER images confirm that lobate scarps are the dominant tectonic landform and record global contraction associated with cooling of the planet. The history of contraction can be related to the history of volcanism and cratering, and the total contractional strain is at least one-third greater than inferred from Mariner 10 images. On the basis of measurements of thermal neutrons made during the flyby, the average abundance of iron in Mercury's surface material is less than 6% by weight.

  14. Astrophysical objects observed by the MESSENGER X-ray spectrometer during Mercury flybys

    CERN Document Server

    Bannister, N P; Lindsay, S T; Martindale, A; Talboys, D L

    2012-01-01

    The MESSENGER spacecraft conducted its first flyby of Mercury on 14th January 2008, followed by two subsequent encounters on 6th October 2008 and 29th September 2009, prior to Mercury orbit insertion on 18th March 2011. We have reviewed MESSENGER flight telemetry and X-ray Spectrometer observations from the first two encounters, and correlate several prominent features in the data with the presence of astrophysical X-ray sources in the instrument field of view. We find that two X-ray peaks attributed in earlier work to the detection of suprathermal electrons from the Mercury magnetosphere, are likely to contain a significant number of events that are of astrophysical origin. The intensities of these two peaks cannot be explained entirely on the basis of astrophysical sources, and we support the previous suprathermal explanation but suggest that the electron fluxes derived in those studies be revised to correct for a significant astrophysical signal.

  15. JUPITER and satellites: Clinical implications of the JUPITER study and its secondary analyses.

    Science.gov (United States)

    Kostapanos, Michael S; Elisaf, Moses S

    2011-07-26

    THE JUSTIFICATION FOR THE USE OF STATINS IN PREVENTION: an intervention trial evaluating rosuvastatin (JUPITER) study was a real breakthrough in primary cardiovascular disease prevention with statins, since it was conducted in apparently healthy individuals with normal levels of low-density lipoprotein cholesterol (LDL-C JUPITER, rosuvastatin was associated with significant reductions in cardiovascular outcomes as well as in overall mortality compared with placebo. In this paper the most important secondary analyses of the JUPITER trial are discussed, by focusing on their novel findings regarding the role of statins in primary prevention. Also, the characteristics of otherwise healthy normocholesterolemic subjects who are anticipated to benefit more from statin treatment in the clinical setting are discussed. Subjects at "intermediate" or "high" 10-year risk according to the Framingham score, those who exhibit low post-treatment levels of both LDL-C (JUPITER added to our knowledge that statins may be effective drugs in the primary prevention of cardiovascular disease in normocholesterolemic individuals at moderate-to-high risk. Also, statin treatment may reduce the risk of venous thromboembolism and preserve renal function. An increase in physician-reported diabetes represents a major safety concern associated with the use of the most potent statins.

  16. THE CLOSEST KNOWN FLYBY OF A STAR TO THE SOLAR SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Mamajek, Eric E. [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 (United States); Barenfeld, Scott A. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Ivanov, Valentin D.; Boffin, Henri M. J. [European Southern Observatory, Av. Alonso de Cordova 3107, 19001 Casilla, Santiago 19 (Chile); Kniazev, Alexei Y.; Väisänen, Petri [South African Astronomical Observatory, P.O. Box 9, 7935 Observatory, Cape Town (South Africa); Beletsky, Yuri, E-mail: emamajek@pas.rochester.edu [Las Campanas Observatory, Carnegie Institution of Washington, Colina el Pino, Casilla 601 La Serena (Chile)

    2015-02-10

    Passing stars can perturb the Oort Cloud, triggering comet showers and potentially extinction events on Earth. We combine velocity measurements for the recently discovered, nearby, low-mass binary system WISE J072003.20-084651.2 (“Scholz’s star”) to calculate its past trajectory. Integrating the Galactic orbits of this ∼0.15 M{sub ⊙} binary system and the Sun, we find that the binary passed within only 52{sup +23}{sub −14} kAU (0.25{sup +0.11}{sub −0.07} pc) of the Sun 70{sup +15}{sub −10} kya (1σ uncertainties), i.e., within the outer Oort Cloud. This is the closest known encounter of a star to our solar system with a well-constrained distance and velocity. Previous work suggests that flybys within 0.25 pc occur infrequently (∼0.1 Myr{sup −1}). We show that given the low mass and high velocity of the binary system, the encounter was dynamically weak. Using the best available astrometry, our simulations suggest that the probability that the star penetrated the outer Oort Cloud is ∼98%, but the probability of penetrating the dynamically active inner Oort Cloud (<20 kAU) is ∼10{sup −4}. While the flyby of this system likely caused negligible impact on the flux of long-period comets, the recent discovery of this binary highlights that dynamically important Oort Cloud perturbers may be lurking among nearby stars.

  17. CAPTURE OF TROJANS BY JUMPING JUPITER

    Energy Technology Data Exchange (ETDEWEB)

    Nesvorny, David [Department of Space Studies, Southwest Research Institute, 1050 Walnut St., Suite 300, Boulder, CO 80302 (United States); Vokrouhlicky, David [Institute of Astronomy, Charles University, V Holesovickach 2, 180 00 Prague 8 (Czech Republic); Morbidelli, Alessandro [Departement Cassiopee, University of Nice, CNRS, Observatoire de la Cote d' Azur, Nice, F-06304 (France)

    2013-05-01

    Jupiter Trojans are thought to be survivors of a much larger population of planetesimals that existed in the planetary region when planets formed. They can provide important constraints on the mass and properties of the planetesimal disk, and its dispersal during planet migration. Here, we tested a possibility that the Trojans were captured during the early dynamical instability among the outer planets (aka the Nice model), when the semimajor axis of Jupiter was changing as a result of scattering encounters with an ice giant. The capture occurs in this model when Jupiter's orbit and its Lagrange points become radially displaced in a scattering event and fall into a region populated by planetesimals (that previously evolved from their natal transplanetary disk to {approx}5 AU during the instability). Our numerical simulations of the new capture model, hereafter jump capture, satisfactorily reproduce the orbital distribution of the Trojans and their total mass. The jump capture is potentially capable of explaining the observed asymmetry in the number of leading and trailing Trojans. We find that the capture probability is (6-8) Multiplication-Sign 10{sup -7} for each particle in the original transplanetary disk, implying that the disk contained (3-4) Multiplication-Sign 10{sup 7} planetesimals with absolute magnitude H < 9 (corresponding to diameter D = 80 km for a 7% albedo). The disk mass inferred from this work, M{sub disk} {approx} 14-28 M{sub Earth}, is consistent with the mass deduced from recent dynamical simulations of the planetary instability.

  18. Radiative and dynamical modeling of Jupiter's atmosphere

    Science.gov (United States)

    Guerlet, Sandrine; Spiga, Aymeric

    2016-04-01

    Jupiter's atmosphere harbours a rich meteorology, with alternate westward and eastward zonal jets, waves signatures and long-living storms. Recent ground-based and spacecraft measurements have also revealed a rich stratospheric dynamics, with the observation of thermal signatures of planetary waves, puzzling meridional distribution of hydrocarbons at odds with predictions of photochemical models, and a periodic equatorial oscillation analogous to the Earth's quasi-biennal oscillation and Saturn's equatorial oscillation. These recent observations, along with the many unanswered questions (What drives and maintain the equatorial oscillations? How important is the seasonal forcing compared to the influence of internal heat? What is the large-scale stratospheric circulation of these giant planets?) motivated us to develop a complete 3D General Circulation Model (GCM) of Saturn and Jupiter. We aim at exploring the large-scale circulation, seasonal variability, and wave activity from the troposphere to the stratosphere of these giant planets. We will briefly present how we adapted our existing Saturn GCM to Jupiter. One of the main change is the addition of a stratospheric haze layer made of fractal aggregates in the auroral regions (poleward of 45S and 30N). This haze layer has a significant radiative impact by modifying the temperature up to +/- 15K in the middle stratosphere. We will then describe the results of radiative-convective simulations and how they compare to recent Cassini and ground-based temperature measurements. These simulations reproduce surprisingly well some of the observed thermal vertical and meridional gradients, but several important mismatches at low and high latitudes suggest that dynamics also plays an important role in shaping the temperature field. Finally, we will present full GCM simulations and discuss the main resulting features (waves and instabilities). We will also and discuss the impact of the choice of spatial resolution and

  19. A Possibly Universal Red Chromophore for Jupiter

    Science.gov (United States)

    Sromovsky, Lawrence A.; Baines, Kevin; Fry, Patrick M.

    2016-10-01

    A new laboratory-generated chemical compound made from photodissociated ammonia (NH3) molecules reacting with acetylene (C2H2) was suggested as a possible coloring agent for Jupiter's Great Red Spot (GRS) by Carlson et al. (2016, Icarus 274, 106-115). Baines et al. (2016, AAS/DPS Meeting abstract) showed that the GRS spectrum measured by the visual channels of the Cassini VIMS instrument in 2000 could be accurately fit by a cloud model in which the chromophore appeared as small particles in a physically thin layer immediately above the main cloud layer of the GRS. Here we show that the same chromophore and similar layer structure can also provide close matches to the 0.4-1 micron spectra of many other cloud features on Jupiter, suggesting that this material may be a nearly universal chromophore responsible for the various degrees of red coloration on Jupiter. This is a robust conclusion, even for 12 percent changes in VIMS calibration and large uncertainties in the refractive index of the main cloud layer due to uncertain fractions of NH4SH and NH3 in its cloud particles. The chromophore layer can account for color variations among north and south equatorial belts, equatorial zone, and the Great Red Spot, by varying particle size from 0.12 to 0.29 micron and optical depth from 0.06 to 0.76. The total mass of the chromophore layer is much less variable than its optical depth, staying mainly within 6-10 micrograms/cm2 range, but is only about half that amount in the equatorial zone. We also found a depression of the ammonia volume mixing ratio in the two belt regions, which averaged 0.4-0.5 × 10-4 immediately below the ammonia condensation level, while the other regions averaged twice that value.LAS and PMF acknowledge support from NASA Grant NNX14AH40G.

  20. Equatorial Oscillations in Jupiter's and Saturn's Atmospheres

    Science.gov (United States)

    Flasar, F. Michael; Guerlet, S.; Fouchet, T.; Schinder, P. J.

    2011-01-01

    Equatorial oscillations in the zonal-mean temperatures and zonal winds have been well documented in Earth's middle atmosphere. A growing body of evidence from ground-based and Cassini spacecraft observations indicates that such phenomena also occur in the stratospheres of Jupiter and Saturn. Earth-based midinfrared measurements spanning several decades have established that the equatorial stratospheric temperatures on Jupiter vary with a cycle of 4-5 years and on Saturn with a cycle of approximately 15 years. Spectra obtained by the Composite Infrared Spectrometer (CIRS) during the Cassini swingby at the end of 2000, with much better vertical resolution than the ground-based data, indicated a series of vertically stacked warm and cold anomalics at Jupiter's equator; a similar structurc was seen at Saturn's equator in CIRS limb measurements made in 2005, in the early phase of Cassini's orbital tour. The thermal wind equation implied similar patterns of mean zonal winds increasing and decreasing with altitude. On Saturn the peak-to-pcak amplitude of this variation was nearly 200 meters per second. The alternating vertical pattern of wanner and colder cquatorial tcmperatures and easterly and westerly tendencies of the zonal winds is seen in Earth's equatorial oscillations, where the pattern descends with time, The Cassini Jupiter and early Saturn observations were snapshots within a limited time interval, and they did not show the temporal evolution of the spatial patterns. However, more recent Saturn observations by CIRS (2010) and Cassini radio-occultation soundings (2009-2010) have provided an opportunity to follow the change of the temperature-zonal wind pattern, and they suggest there is descent, at a rate of roughly one scale height over four years. On Earth, the observed descent in the zonal-mean structure is associated with the absorption of a combination of vertically propagating waves with easlerly and westerly phase velocities. The peak-to-peak zonal wind

  1. Feasibility Study of Jupiter Icy Moons Orbiter Permanent Magnet Alternator Start Sequence

    Science.gov (United States)

    Kenny, Barbara H.; Tokars, Roger P.

    2006-01-01

    The Jupiter Icy Moons Orbiter (JIMO) mission was a proposed, (recently cancelled) long duration science mission to study three moons of Jupiter: Callisto, Ganymede, and Europa. One design of the JIMO spacecraft used a nuclear heat source in conjunction with a Brayton rotating machine to generate electrical power for the electric thrusters and the spacecraft bus. The basic operation of the closed cycle Brayton system was as follows. The working fluid, a heliumxenon gas mixture, first entered a compressor, then went through a recuperator and hot-side heat exchanger, then expanded across a turbine that drove an alternator, then entered the cold-side of the recuperator and heat exchanger and finally returned to the compressor. The spacecraft was to be launched with the Brayton system off-line and the nuclear reactor shut down. Once the system was started, the helium-xenon gas would be circulated into the heat exchangers as the nuclear reactors were activated. Initially, the alternator unit would operate as a motor so as to drive the turbine and compressor to get the cycle started. This report investigated the feasibility of the start up sequence of a permanent magnet (PM) machine, similar in operation to the alternator unit, without any position or speed feedback sensors ("sensorless") and with a variable load torque. It is found that the permanent magnet machine can start with sensorless control and a load torque of up to 30 percent of the rated value.

  2. Forum on Concepts and Approaches for Jupiter Icy Moons Orbiter

    Science.gov (United States)

    2003-01-01

    The papers presented at this conference primarily discuss instruments and techniques for conducting science on Jupiter's icy moons, and geologic processes on the moons themselves. Remote sensing of satellites, cratering on satellites, and ice on the surface of Europa are given particular attention. Some papers discuss Jupiter's atmosphere, or exobiology.

  3. Periodic changes of the activity of processes in Jupiter's atmosphere

    Science.gov (United States)

    Vidmachenko, A. P.

    2016-10-01

    Variations of the Earth jovimagnetic latitude on Jupiter are preferred in solar-driven changes of reflective properties of clouds and haze on Jupiter. Because of the orbit eccentricity (e=0,048450) the northern hemisphere receives 21% greater solar energy flow to the atmosphere, because Jupiter is in the perihelia near the time of the summer solstice. Results of our studies showed that the ratio of the brightness of the northern and southern tropical and temperate regions is evident factor of the photometric activity of the Jupiter's atmospheric processes. The obtained from the analysis of observational data for the period from 1962 to 2015 existence of variations of activity factor of the planet hemispheres with a period of 11.86 years has allowed us to talk about an existence of the seasonal reconstruction of the physical parameters of Jupiter's atmosphere.

  4. Target selection and transfer trajectories design for exploring asteroid mission

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Technique of target selection and profiles of transfer trajectory for Chinese asteroid exploring mission are studied systemically.A complete set of approaches to selecting mission targets and designing the transfer trajectory is proposed.First,when selecting a target for mission,some factors regarded as the scientific motivations are discussed.Then,when analyzing the accessibility of targets,instead of the classical strategy,the multiple gravity-assist strategy is provided.The suitable and possible targets,taking into account scientific value and technically feasible,are obtained via selection and estimation.When designing the transfer trajectory for exploring asteroid mission,an approach to selecting gravity-assist celestial body is proposed.Finally,according to the mission constraints,the trajectory profile with 2-years △V-EGA for exploring asteroid is presented.Through analyzing the trajectory profile,unexpected result that the trajectory would pass by two main-belts asteroids is found.So,the original proposal is extended to the multiple flybys mission.It adds the scientific return for asteroid mission.

  5. Jupiter's Decameter Radiation as Viewed from Juno, Cassini, WIND, STEREO A, and Earth-Based Radio Observatories

    Science.gov (United States)

    Imai, Masafumi; Kurth, William S.; Hospodarsky, George B.; Bolton, Scott J.; Connerney, John E. P.; Levin, Steven M.; Clarke, Tracy E.; Higgins, Charles A.

    2017-04-01

    Jupiter is the dominant auroral radio source in our solar system, producing decameter (DAM) radiation (from a few to 40 MHz) with a flux density of up to 10-19 W/(m2Hz). Jovian DAM non-thermal radiation above 10 MHz is readily observed by Earth-based radio telescopes that are limited at lower frequencies by terrestrial ionospheric conditions and radio frequency interference. In contrast, frequencies observed by spacecraft depend upon receiver capability and the ambient solar wind plasma frequency. Observations of DAM from widely separated observers can be used to investigate the geometrical properties of the beam and learn about the generation mechanism. The first multi-observer observations of Jovian DAM emission were made using the Voyager spacecraft and ground-based radio telescopes in early 1979, but, due to geometrical constraints and limited flyby duration, a full understanding of the latitudinal beaming of Jovian DAM radiation remains elusive. This understanding is sorely needed to confirm DAM generation by the electron cyclotron maser instability, the widely assumed generation mechanism. Juno first detected Jovian DAM emissions on May 5, 2016, on approach to the Jovian system, initiating a new opportunity to perform observations of Jovian DAM radiation with Juno, Cassini, WIND, STEREO A, and Earth-based radio observatories (Long Wavelength Array Station One (LWA1) in New Mexico, USA, and Nançay Decameter Array (NDA) in France). These observers are widely distributed throughout our solar system and span a broad frequency range of 3.5 to 40.5 MHz. Juno resides in orbit at Jupiter, Cassini at Saturn, WIND around Earth, STEREO A in 1 AU orbit, and LWA1 and NDA at Earth. Juno's unique polar trajectory is expected to facilitate extraordinary stereoscopic observations of Jovian DAM, leading to a much improved understanding of the latitudinal beaming of Jovian DAM.

  6. Elliptical instability in hot Jupiter systems

    CERN Document Server

    Cébron, David; Gal, Patrice Le; Moutou, Claire; Leconte, J; Sauret, Alban

    2013-01-01

    Several studies have already considered the influence of tides on the evolution of systems composed of a star and a close-in companion to tentatively explain different observations such as the spin-up of some stars with hot Jupiters, the radius anomaly of short orbital period planets and the synchronization or quasi-synchronization of the stellar spin in some extreme cases. However, the nature of the mechanism responsible for the tidal dissipation in such systems remains uncertain. In this paper, we claim that the so-called elliptical instability may play a major role in these systems, explaining some systematic features present in the observations. This hydrodynamic instability, arising in rotating flows with elliptical streamlines, is suspected to be present in both planet and star of such systems, which are elliptically deformed by tides. The presence and the influence of the elliptical instability in gaseous bodies, such as stars or hot Jupiters, are most of the time neglected. In this paper, using numeri...

  7. Fading of Jupiter's South Equatorial Belt

    Science.gov (United States)

    Sola, Michael A.; Orton, Glenn; Baines, Kevin; Yanamandra-Fisher, Padma

    2011-01-01

    One of Jupiter's most dominant features, the South Equatorial Belt, has historically gone through a "fading" cycle. The usual dark, brownish clouds turn white, and after a period of time, the region returns to its normal color. Understanding this phenomenon, the latest occurring in 2010, will increase our knowledge of planetary atmospheres. Using the near infrared camera, NSFCAM2, at NASA's Infrared Telescope Facility in Hawaii, images were taken of Jupiter accompanied by data describing the circumstances of each observation. These images are then processed and reduced through an IDL program. By scanning the central meridian of the planet, graphs were produced plotting the average values across the central meridian, which are used to find variations in the region of interest. Calculations using Albert4, a FORTRAN program that calculates the upwelling reflected sunlight from a designated cloud model, can be used to determine the effects of a model atmosphere due to various absorption, scattering, and emission processes. Spectra that were produced show ammonia bands in the South Equatorial Belt. So far, we can deduce from this information that an upwelling of ammonia particles caused a cloud layer to cover up the region. Further investigations using Albert4 and other models will help us to constrain better the chemical make up of the cloud and its location in the atmosphere.

  8. ECCENTRIC JUPITERS VIA DISK–PLANET INTERACTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Duffell, Paul C.; Chiang, Eugene, E-mail: duffell@berkeley.edu, E-mail: echiang@astro.berkeley.edu [Department of Astronomy and Theoretical Astrophysics Center, University of California, Berkeley (United States)

    2015-10-20

    Numerical hydrodynamics calculations are performed to determine the conditions under which giant planet eccentricities can be excited by parent gas disks. Unlike in other studies, Jupiter-mass planets are found to have their eccentricities amplified—provided their orbits start off as eccentric. We disentangle the web of co-rotation, co-orbital, and external resonances to show that this finite-amplitude instability is consistent with that predicted analytically. Ellipticities can grow until they reach of order of the disk's aspect ratio, beyond which the external Lindblad resonances that excite eccentricity are weakened by the planet's increasingly supersonic epicyclic motion. Forcing the planet to still larger eccentricities causes catastrophic eccentricity damping as the planet collides into gap walls. For standard parameters, the range of eccentricities for instability is modest; the threshold eccentricity for growth (∼0.04) is not much smaller than the final eccentricity to which orbits grow (∼0.07). If this threshold eccentricity can be lowered (perhaps by non-barotropic effects), and if the eccentricity driving documented here survives in 3D, it may robustly explain the low-to-moderate eccentricities ≲0.1 exhibited by many giant planets (including Jupiter and Saturn), especially those without planetary or stellar companions.

  9. Thermal Processes Governing Hot-Jupiter Radii

    CERN Document Server

    Spiegel, David S

    2013-01-01

    There have been many proposed explanations for the larger-than-expected radii of some transiting hot Jupiters, including either stellar or orbital energy deposition deep in the atmosphere or deep in the interior. In this paper, we explore the important influences on hot-Jupiter radius evolution of (i) additional heat sources in the high atmosphere, the deep atmosphere, and deep in the convective interior; (ii) consistent cooling of the deep interior through the planetary dayside, nightside, and poles; (iii) the degree of heat redistribution to the nightside; and (iv) the presence of an upper atmosphere absorber inferred to produce anomalously hot upper atmospheres and inversions in some close-in giant planets. In particular, we compare the radius expansion effects of atmospheric and deep-interior heating at the same power levels and derive the power required to achieve a given radius increase when night-side cooling is incorporated. We find that models that include consistent day/night cooling are more simila...

  10. Broadband Linear Polarization of Jupiter Trojans

    CERN Document Server

    Bagnulo, S; Stinson, A; Christou, A; Borisov, G B

    2016-01-01

    Trojan asteroids orbit in the Lagrange points of the system Sun-planet-asteroid. Their dynamical stability make their physical properties important proxies for the early evolution of our solar system. To study their origin, we want to characterize the surfaces of Jupiter Trojan asteroids and check possible similarities with objects of the main belt and of the Kuiper Belt. We have obtained high-accuracy broad-band linear polarization measurements of six Jupiter Trojans of the L4 population and tried to estimate the main features of their polarimetric behaviour. We have compared the polarimetric properties of our targets among themselves, and with those of other atmosphere-less bodies of our solar system. Our sample show approximately homogeneous polarimetric behaviour, although some distinct features are found between them. In general, the polarimetric properties of Trojan asteroids are similar to those of D- and P-type main-belt asteroids. No sign of coma activity is detected in any of the observed objects. A...

  11. The Transit Spectra of Earth and Jupiter

    CERN Document Server

    Irwin, Patrick G J; Bowles, Neil E; Fletcher, Leigh N; Aigrain, Suzanne; Lee, Jae-Min

    2014-01-01

    In recent years, a number of observations have been made of the transits of 'Hot Jupiters', such as HD 189733b, which have been modelled to derive atmospheric structure and composition. As measurement techniques improve, the transit spectra of 'Super-Earths' such as GJ 1214b are becoming better constrained, allowing model atmospheres to be fitted for this class of planet also. While it is not yet possible to constrain the atmospheric states of small planets such as the Earth or cold planets like Jupiter, this may become practical in the coming decades and if so, it is of interest to determine what we might infer from such measurements. Here we have constructed atmospheric models of the Solar System planets from 0.4 - 15.5 microns that are consistent with ground-based and satellite observations and from these calculate the primary transit and secondary eclipse spectra (with respect to the Sun and typical M-dwarfs) that would be observed by a 'remote observer', many light years away. From these spectra we test ...

  12. Tidal Response of Preliminary Jupiter Model

    Science.gov (United States)

    Wahl, Sean M.; Hubbard, William B.; Militzer, Burkhard

    2016-11-01

    In anticipation of improved observational data for Jupiter’s gravitational field, from the Juno spacecraft, we predict the static tidal response for a variety of Jupiter interior models based on ab initio computer simulations of hydrogen-helium mixtures. We calculate hydrostatic-equilibrium gravity terms, using the non-perturbative concentric Maclaurin Spheroid method that eliminates lengthy expansions used in the theory of figures. Our method captures terms arising from the coupled tidal and rotational perturbations, which we find to be important for a rapidly rotating planet like Jupiter. Our predicted static tidal Love number, {k}2=0.5900, is ˜10% larger than previous estimates. The value is, as expected, highly correlated with the zonal harmonic coefficient J 2, and is thus nearly constant when plausible changes are made to the interior structure while holding J 2 fixed at the observed value. We note that the predicted static k 2 might change, due to Jupiter’s dynamical response to the Galilean moons, and find reasons to argue that the change may be detectable—although we do not present here a theory of dynamical tides for highly oblate Jovian planets. An accurate model of Jupiter’s tidal response will be essential for interpreting Juno observations and identifying tidal signals from effects of other interior dynamics of Jupiter’s gravitational field.

  13. Global Optimization of Interplanetary Trajectories in the Presence of Realistic Mission Contraints

    Science.gov (United States)

    Hinckley, David, Jr.; Englander, Jacob; Hitt, Darren

    2015-01-01

    Interplanetary missions are often subject to difficult constraints, like solar phase angle upon arrival at the destination, velocity at arrival, and altitudes for flybys. Preliminary design of such missions is often conducted by solving the unconstrained problem and then filtering away solutions which do not naturally satisfy the constraints. However this can bias the search into non-advantageous regions of the solution space, so it can be better to conduct preliminary design with the full set of constraints imposed. In this work two stochastic global search methods are developed which are well suited to the constrained global interplanetary trajectory optimization problem.

  14. Trajectory Design to Mitigate Risk on the Transiting Exoplanet Survey Satellite (TESS) Mission

    Science.gov (United States)

    Dichmann, Donald

    2016-01-01

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

  15. Cometary Coma Chemical Composition (C4) Mission

    Science.gov (United States)

    Carle, Glenn C.; Clark, Benton C.; Knocke, Philip C.; OHara, Bonnie J.; Adams, Larry; Niemann, Hasso B.; Alexander, Merle; Veverka, Joseph; Goldstein, Raymond; Huebner, Walter; Morrison, David (Technical Monitor)

    1994-01-01

    Cometary exploration remains of great importance to virtually all of space science. Because comets are presumed to be remnants of the early solar nebula, they are expected to provide fundamental knowledge as to the origin and development of the solar system as well as to be key to understanding of the source of volatiles and even life itself in the inner solar system. Clearly the time for a detailed study of the composition of these apparent messages from the past has come. A comet rendezvous mission, the Cometary Coma Chemical Composition (C4) Mission, is now being studied as a candidate for the new Discovery program. This mission is a highly-focussed and usefully-limited subset of the Cometary Rendezvous Asteroid Flyby (CRAF) Mission. The C4 mission will concentrate on measurements that will produce an understanding of the composition and physical makeup of a cometary nucleus. The core science goals of the C4 mission are 1) to determine the chemical, elemental, and isotopic composition of a cometary nucleus and 2) to characterize the chemical and isotopic nature of its atmosphere. A related goal is to obtain temporal information about the development of the cometary coma as a function of time and orbital position. The four short-period comets -- Tempel 1, Tempel 2, Churyumov-Gerasimenko, and Wirtanen -which all appear to have acceptable dust production rates, were identified as candidate targets. Mission opportunities have been identified beginning as early as 1998. Tempel I with a launch in 1999, however, remains the baseline comet for studies of and planning the C4 mission. The C4 mission incorporates two science instruments and two engineering instruments in the payload to obtain the desired measurements. The science instruments include an advanced version of the Cometary Ice and Dust Experiment (CIDEX), a mini-CIDEX with a sample collection system, an X-ray Fluorescence Spectrometer and a Pyrolysis-Gas Chromatograph, and a simplified version of the Neutral

  16. Monte Carlo Analysis as a Trajectory Design Driver for the TESS Mission

    Science.gov (United States)

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

    2016-01-01

    The Transiting Exoplanet Survey Satellite (TESS) will be injected into a highly eccentric Earth orbit and fly 3.5 phasing loops followed by a lunar flyby to enter a mission orbit with lunar 2:1 resonance. Through the phasing loops and mission orbit, the trajectory is significantly affected by lunar and solar gravity. We have developed a trajectory design to achieve the mission orbit and meet mission constraints, including eclipse avoidance and a 30-year geostationary orbit avoidance requirement. A parallelized Monte Carlo simulation was performed to validate the trajectory after injecting common perturbations, including launch dispersions, orbit determination errors, and maneuver execution errors. The Monte Carlo analysis helped identify mission risks and is used in the trajectory selection process.

  17. Monte Carlo Analysis as a Trajectory Design Driver for the Transiting Exoplanet Survey Satellite (TESS) Mission

    Science.gov (United States)

    Nickel, Craig; Parker, Joel; Dichmann, Don; Lebois, Ryan; Lutz, Stephen

    2016-01-01

    The Transiting Exoplanet Survey Satellite (TESS) will be injected into a highly eccentric Earth orbit and fly 3.5 phasing loops followed by a lunar flyby to enter a mission orbit with lunar 2:1 resonance. Through the phasing loops and mission orbit, the trajectory is significantly affected by lunar and solar gravity. We have developed a trajectory design to achieve the mission orbit and meet mission constraints, including eclipse avoidance and a 30-year geostationary orbit avoidance requirement. A parallelized Monte Carlo simulation was performed to validate the trajectory after injecting common perturbations, including launch dispersions, orbit determination errors, and maneuver execution errors. The Monte Carlo analysis helped identify mission risks and is used in the trajectory selection process.

  18. A close-up view of Jupiter's magnetic field from Juno: New insights into the planet's deep interior

    Science.gov (United States)

    Jones, Chris A.; Holme, Richard

    2017-06-01

    The first results from the Juno mission magnetometer have recently become available. Juno provides us with the closest view of any planetary dynamo, flying to within 1.25 of the radius of the dynamo region, whereas for the Earth, we cannot get closer than 1.83 of the core-mantle boundary radius. We compare the Juno results with those from first principles dynamo simulations of Jupiter's magnetic field. Intense flux patches at Jupiter's surface are found in both the data and the simulations, though the simulations have them mainly at slightly higher latitudes than the observations. We consider the prospects for determining more accurately the location of the top of the metallic hydrogen region and the implications of possible weak flux patches at the poles.

  19. Dynamical Interactions Make Hot Jupiters in Open Star Clusters

    CERN Document Server

    Shara, Michael M; Mardling, Rosemary A

    2014-01-01

    Explaining the origin and evolution of exoplanetary "hot Jupiters" remains a significant challenge. One possible mechanism for their production is planet-planet interactions, which produces hot Jupiters from planets born far from their host stars but near their dynamical stability limits. In the much more likely case of planets born far from their dynamical stability limits, can hot Jupiters can be formed in star clusters? Our N-body simulations of planetary systems inside star clusters answer this question in the affirmative, and show that hot Jupiter formation is not a rare event. We detail three case studies of the dynamics-induced births of hot Jupiters on highly eccentric orbits that can only occur inside star clusters. The hot Jupiters' orbits bear remarkable similarities to those of some of the most extreme exoplanets known: HAT-P-32 b, HAT-P-2 b, HD 80606 b and GJ 876 d. If stellar perturbations formed these hot Jupiters then our simulations predict that these very hot, inner planets are sometimes acc...

  20. Jupiter's Decametric Radio Emission and the Radiation Belts of Its Galilean Satellites.

    Science.gov (United States)

    Burns, J A

    1968-03-01

    Many of the observed properties of Jupiter's decametric radiation may be explained by postulation that the inner Galilean satellites of Jupiter have magnetic properties that strongly distort Jupiter's magnetic field in the region of each satellite. Charged particles from Jupiter's radiation belts are trapped by these distorted fields and emit synchrotron radiation.

  1. Exoplanet Searches by Future Deep Space Missions

    Directory of Open Access Journals (Sweden)

    Maccone C.

    2011-02-01

    Full Text Available The search for exoplanets could benefit from gravitational lensing if we could get to 550 AU from the Sun and beyond. This is because the gravitational lens of the Sun would highly intensify there any weak electromagnetic wave reaching the solar system from distant planets in the Galaxy (see Maccone 2009. The gravitational lens of the Sun, however, has a drawback: the solar Corona. Electrons in the Corona make electromagnetic waves diverge and this pushes the focus out to distances higher than 550 AU. Jupiter is the second larger mass in the solar system after the Sun, but in this focal game not only the mass matters: rather, what really matters is the ratio between the radius of the body squared and the mass of the body. In this regard, Jupiter qualifies as the second best choice for a space mission, requiring the spacecraft to reach 6,077 AU. In this paper, we study the benefit of exoplanet searches by deep space missions.

  2. Orbit Determination Covariance Analysis for the Europa Clipper Mission

    Science.gov (United States)

    Ionasescu, Rodica; Martin-Mur, Tomas; Valerino, Powtawche; Criddle, Kevin; Buffington, Brent; McElrath, Timothy

    2014-01-01

    A new Jovian satellite tour is proposed by NASA, which would include numerous flybys of the moon Europa, and would explore its potential habitability by characterizing the existence of any water within and beneath Europa's ice shell. This paper describes the results of a covariance study that was undertaken on a sample tour to assess the navigational challenges and capabilities of such a mission from an orbit determination (OD) point of view, and to help establish a delta V budget for the maneuvers needed to keep the spacecraft on the reference trajectory. Additional parametric variations from the baseline case were also investigated. The success of the Europa Clipper mission will depend on the science measurements that it will enable. Meeting the requirements of the instruments onboard the spacecraft is an integral part of this analysis.

  3. Energetic electrons in Jupiter's dawn magnetodisc

    Science.gov (United States)

    Van Allen, J. A.

    1979-01-01

    The paper presents and analyzes absolute energy density data on electrons from the University of Iowa instrument on Pioneer 10 for one example of a plasma sheet traversal in Jupiter's dawn magnetodisk on 6-7 December 1973. The absolute integral omnidirectional intensity spectrum of electrons is based on a full and accurate reduction of the counting rate data. The main finding is that electrons of energy greater than 0.060 MeV provide only about 3% of the charged particle pressure required to explain the observed depression in the magnetic field at the center of the plasma sheet, in spite of the fact that the intensity of such electrons is well correlated with the depression of the magnetic pressure throughout the sheet.

  4. The dusty ballerina skirt of Jupiter

    Science.gov (United States)

    Horanyi, M.; Morfill, G.; Gruen, E.

    1993-12-01

    We suggest a model to explain the unexpected recurrent dust events that were observed during the Jupiter encounter by the dust detector on board the Ulysses spacecraft. This model is based dust-magnetosphere interactions. Dust particles inside the Jovian magnetosphere collect electrostatic charges and their interaction with the magnetic and electric fields can lead to energization and subsequent ejection. We discuss the dusty regions (ring/halo, `gossamer' ring) and also Io as potential sources for the Ulysses events. This model favors Io as a source. The mass and velocity range of the escaping particles are compatible with the observations, and we also suggest internal periodicities to explain the recurrent nature of the Ulysses dust events.

  5. Auroral meridian scanning photometer calibration using Jupiter

    Science.gov (United States)

    Jackel, Brian J.; Unick, Craig; Creutzberg, Fokke; Baker, Greg; Davis, Eric; Donovan, Eric F.; Connors, Martin; Wilson, Cody; Little, Jarrett; Greffen, M.; McGuffin, Neil

    2016-10-01

    Observations of astronomical sources provide information that can significantly enhance the utility of auroral data for scientific studies. This report presents results obtained by using Jupiter for field cross calibration of four multispectral auroral meridian scanning photometers during the 2011-2015 Northern Hemisphere winters. Seasonal average optical field-of-view and local orientation estimates are obtained with uncertainties of 0.01 and 0.1°, respectively. Estimates of absolute sensitivity are repeatable to roughly 5 % from one month to the next, while the relative response between different wavelength channels is stable to better than 1 %. Astronomical field calibrations and darkroom calibration differences are on the order of 10 %. Atmospheric variability is the primary source of uncertainty; this may be reduced with complementary data from co-located instruments.

  6. Radio observations of Jupiter-family comets

    CERN Document Server

    Crovisier, J; Bockelée-Morvan, D; Colom, P

    2008-01-01

    Radio observations from decimetric to submillimetric wavelengths are now a basic tool for the investigation of comets. Spectroscopic observations allow us i) to monitor the gas production rate of the comets, by directly observing the water molecule, or by observing secondary products (e.g., the OH radical) or minor species (e.g., HCN); ii) to investigate the chemical composition of comets; iii) to probe the physical conditions of cometary atmospheres: kinetic temperature and expansion velocity. Continuum observations probe large-size dust particles and (for the largest objects) cometary nuclei. Comets are classified from their orbital characteristics into two separate classes: i) nearly-isotropic, mainly long-period comets and ii) ecliptic, short-period comets, the so-called Jupiter-family comets. These two classes apparently come from two different reservoirs, respectively the Oort cloud and the trans-Neptunian scattered disc. Due to their different history and - possibly - their different origin, they may h...

  7. Rotational Properties of Jupiter Trojan 1173 Anchises

    Science.gov (United States)

    Chatelain, Joseph; Henry, Todd; French, Linda; Trilling, David

    2015-11-01

    Anchises (1173) is a large Trojan asteroid librating about Jupiter’s L5 Lagrange point. Here we examine its rotational and lightcurve properties by way of data collected over a 3.5 year observing campaign. The length of the campaign means that data were gathered for more than a quarter of Anchises' full orbital revolution which allows for accurate determinations of pole orientation and bulk shape properties for the asteroid that can then be compared to results of previous work (i.e. French 1987, Horner et al. 2012). In addition to light curves, photometric data taken during this campaign could potentially detect color differences between hemispheres as the viewing geometry changes over time. Understanding these details about a prominent member of the Jupiter Trojans may help us better understand the history of this fascinating and important group of asteroids.

  8. Cometary coma chemical composition (C4) mission. [Abstract only

    Science.gov (United States)

    Carle, G. C.; Clark, B. C.; Niemann, H. B.; Alexander, M.; Knocke, P. C.; O'Hara, B. J.

    1994-01-01

    Cometary missions are of enormous fundamental importance for many different space science disciplines, including exobiology. Comets are presumed relics of the earliest, most primitive material in the solar nebula and are related to the planetesimals. They undoubtedly provided a general enrichment of volatiles to the inner solar system (contributing to atmospheres and oceans) and may have been key to the origin of life. A Discovery class, comet rendezvous mission, the Cometary Coma Chemical Composition (C4) Mission, was selected for further study by NASA earlier this year. The C4 Mission is a highly focused and usefully-limited subset of the Cometary Rendezvous Asteroid Flyby (CRAF) Mission, concentrating exclusively on measurements which will lead to an understanding of the chemical composition and make-up of the cometary nucleus. The scientific goals of the Cometary Coma Chemical Composition (C4) Mission are to rendezvous with a short-period comet and (1) to determine the elemental, chemical, and isotopic composition of the nucleus and (2) to characterize the chemical and isotopic nature of its atmosphere. Further, it is a goal to obtain preliminary data on the development of the coma (dust and gas composition) as a function of time and orbital position.

  9. A Transiting Hot Jupiter Orbiting a Metal-Rich Star

    CERN Document Server

    Dunham, Edward W; Koch, David G; Batalha, Natalie M; Buchhave, Lars A; Brown, Timothy M; Caldwell, Douglas A; Cochran, William D; Endl, Michael; Fischer, Debra; Furesz, Gabor; Gautier, Thomas N; Geary, John C; Gilliland, Ronald L; Gould, Alan; Howell, Steve B; Jenkins, Jon M; Kjeldsen, Hans; Latham, David W; Lissauer, Jack J; Marcy, Geoffrey W; Meibom, Soren; Monet, David G; Rowe, Jason F; Sasselov, Dimitar D

    2010-01-01

    We announce the discovery of Kepler-6b, a transiting hot Jupiter orbiting a star with unusually high metallicity, [Fe/H] = +0.34 +/- 0.04. The planet's mass is about 2/3 that of Jupiter, Mp = 0.67 Mj, and the radius is thirty percent larger than that of Jupiter, Rp = 1.32 Rj, resulting in a density of 0.35 g/cc, a fairly typical value for such a planet. The orbital period is P = 3.235 days. The host star is both more massive than the Sun, Mstar = 1.21 Msun, and larger than the Sun, Rstar = 1.39 Rsun.

  10. Maximum frequency of the decametric radiation from Jupiter

    Science.gov (United States)

    Barrow, C. H.; Alexander, J. K.

    1980-01-01

    The upper frequency limits of Jupiter's decametric radio emission are found to be essentially the same when observed from the earth or, with considerably higher sensitivity, from the Voyager spacecraft close to Jupiter. This suggests that the maximum frequency is a real cut-off corresponding to a maximum gyrofrequency of about 38-40 MHz at Jupiter. It no longer appears to be necessary to specify different cut-off frequencies for the Io and non-Io emission as the maximum frequencies are roughly the same in each case.

  11. Resolving Spacecraft Earth-Flyby Anomalies with Measured Light Speed Anisotropy

    Directory of Open Access Journals (Sweden)

    Cahill R. T.

    2008-07-01

    Full Text Available Doppler shift observations of spacecraft, such as Galileo, NEAR, Cassini, Rosetta and MESSENGER in earth flybys, have all revealed unexplained speed “anomalies” — that the Doppler-shift determined speeds are inconsistent with expected speeds. Here it is shown that these speed anomalies are not real and are actually the result of using an incorrect relationship between the observed Doppler shift and the speed of the space- craft — a relationship based on the assumption that the speed of light is isotropic in all frames, viz invariant. Taking account of the repeatedly measured light-speed anisotropy the anomalies are resolved ab initio . The Pioneer 10 / 11 anomalies are discussed, but not resolved. The spacecraft observations demonstrate again that the speed of light is not invariant, and is isotropic only with respect to a dynamical 3-space. The existing Doppler shift data also offers a resource to characterise a new form of gravitational waves, the dynamical 3-space turbulence, that has also been detected by other tech- niques. The Einstein spacetime formalism uses a special definition of space and time coordinates that mandates light speed invariance for all observers, but which is easily misunderstood and misapplied.

  12. An Overview of Ultraviolet Through Infrared Reflectance Spectroscopic Observations of Mercury During the First MESSENGER Flyby

    Science.gov (United States)

    Izenberg, N. R.; McClintock, W. E.; Holsclaw, G. M.; Robinson, M. S.; Blewett, D. T.; Domingue, D. L.; Head, J. W.; Jensen, E. A.; Kochte, M. C.; Lankton, M. R.; Murchie, S. L.; Sprague, A. L.; Vilas, F.; Solomon, S. C.

    2008-05-01

    During the first MESSENGER flyby of Mercury on January 14, 2008, the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) measured reflectance spectra from Mercury's surface over the wavelength range 220-1450 nm. These are the first high-spatial-resolution (Mozart crater and in Tir Planitia. Ground-based observations of Mercury reveal a surface with a red, nearly featureless spectrum in the visible and near-infrared (wavelengths greater than ~ 500 nm) that has been interpreted as evidence for a largely iron-poor feldspathic composition. Initial analyses of VIRS spectra also show strongly red-sloped, near featureless spectra, appearing to support contentions of low iron abundance in surface materials. However, interpretation of Mercury's spectral reflectance is complicated by our lack of knowledge about the effects on its surface materials of space weathering, which both suppresses the strength of spectral absorption features and reddens the spectrum. Brightness variations and absorption bands in ultraviolet reflectance may help determine both the nature and extent of processes that modify observed reflectance at longer wavelengths. MASCS surface observation data demonstrate spectral variations across the Mercury surface that can be related to previous telescopic observations, compared and contrasted with lunar observations, and linked to possible influences of space weathering.

  13. Giant planet formation in stellar clusters: the effects of stellar fly-bys

    CERN Document Server

    Fragner, Moritz

    2009-01-01

    The primary aim of this work is to examine the effect of parabolic stellar encounters on the evolution of a Jovian-mass giant planet forming within a protoplanetary disc. We consider the effect on both the mass accretion and the migration history as a function of encounter distance. We use a grid-based hydrodynamics code to perform 2D simulations of a system consisting of a giant planet embedded within a gaseous disc orbiting around a star, which is perturbed by a passing star on a prograde, parabolic orbit. The disc model extends out to 50 AU, and parabolic encounters are considered with impact parameters ranging from 100 - 250 AU. In agreement with previous work, we find that the disc is significantly tidally truncated for encounters 250 AU, we find that the planet-disc system experiences minimal perturbation. Our results indicate that stellar fly-bys in young clusters may significantly modify the masses and orbital param eters of giant planets forming within protostellar discs. Planets that undergo such e...

  14. Generation of trajectories and choice of routes for a passive flyby of a group of celestial bodies moving in Keplerian orbits.

    Science.gov (United States)

    Akhlebininskij, M. Yu.; Konstantinov, M. S.

    1992-05-01

    The problem of generating trajectories for a flyby of several given celestial bodies moving in Keplerian orbits is solved in a new formulation. It is demonstrated that there exist trajectories along which one vehicle can fly by at least three bodies. A theorem asserting the existence of a trajectory for the flyby of three bodies moving in circular orbits of common radius is formulated and probed. The uniqueness of such trajectories is analyzed. An effective numerical method is proposed for generating trajectories for the flyby of three bodies moving in arbitrary elliptical orbits. The possibilities of the method are illustrated with examples. Questions regarding the insertion of the vehicle into the flyby trajectory are not discussed here.

  15. Space Environment of Mercury at the Time of the First MESSENGER Flyby: Solar Wind and Interplanetary Magnetic Field Modeling of Upstream Conditions

    Science.gov (United States)

    2009-10-01

    passed over the planet (and MESSENGER) several days prior to the flyby of Mercury with the highest-speed (600 km/s) stream features having been expected...when MESSENGER is in orbit around Mercury , the spacecraft will be within the magnetosphere and magnetotail of the planet for extended portions of...TITLE AND SUBTITLE Space environment of Mercury at the time of the first 3HESSENGER flyby: Solar wind and interplanetary magnetic field •Modeling

  16. Using Jupiter's Volatile Inventory to Trace the History Of Ices During Planet Formation

    Science.gov (United States)

    Ciesla, F.

    2014-12-01

    The Galileo probe's measurement of a uniform enrichment of Jupiter's atmosphere in volatiles, including noble gases, relative to a gas of solar composition has proven to be a challenge to models of planet formation. This uniform enrichment requires that Jupiter accreted planetesimals with solar ratios in all elements, except for hydrogen and helium. Given the very low temperatures needed to achieve such compositions if all elements behaved chemically as pure substances, efforts have focused on understanding how extremely volatile elements could be physically incorporated into ices and organics at low temperatures. Two primary methods for incorporation of these volatiles have emerged: formation of clathrate hydrates and trapping of gases during the formation of amorphous ice. These modes for incorporating volatiles make different predictions about the amount of water that would be contained within Jupiter, an issue that will be addressed by the Juno Mission. Either mode for incorporating volatiles will reveal details about the dynamical behavior of ices during planet formation and the environments in which planetary materials were formed. For example, Ciesla (2014) showed that amorphous ice formation, and thus trapping of volatiles in this manner, can occur as water molecules are photodesorbed and freeze-out again on grain surfaces, thus requiring high UV flux environments at the birth of the solar system or significant vertical lofting of grains in the disk by turbulence. I will review the conditions that are required for amorphous trapping and clathrate hydrate formation to have occurred in the solar nebula and discuss the implications for the compositions of the other giant planets and cometary bodies, as well as the relation of these materials to the sources of volatiles on terrestrial planets.

  17. Combining Abundance/Temperature Retrieval with 3D Atmospheric Circulation Simulations of Hot Jupiters

    Science.gov (United States)

    Heng, Kevin

    2011-09-01

    The atmospheres of hot Jupiters are three-dimensional, non-linear entities and understanding them requires the construction of a hierarchy of models of varying sophistication. Since previous work has either focused on the atmospheric dynamics or implemented multi-band radiative transfer, a reasonable approach is to combine the treatment of 3D dynamics with dual-band radiative transfer, where the assumption is that the stellar irradiation and re-emitted radiation from the exoplanet are at distinct wavelengths. I report on the successful implementation of such a setup and demonstrate how it can be used to compute self-consistent temperature-pressure profiles on both the day and night sides of a hot Jupiter, as well as zonal-wind profiles, circulation cell patterns and the angular/temporal offset of the hotspot from the substellar point. In particular, the hotspot offset should aid us in distinguishing between different types of hot Jupiter atmospheres. Together with N. Madhusudhan, we combine the dual-band simulation technique with the abundance/temperature retrieval method of Madhusudhan & Seager, by empirically constraining a range of values for the broad-band opacities which are consistent with the current observations. The advantage of our novel method is that the range of opacities used improves with time as the observations get better. The ability to thoroughly, efficiently and systematically explore the interplay between atmospheric dynamics, radiation and synthetic spectra is an important step forward, as it prepares us for the theoretical interpretation of exoplanetary spectra which will be obtained by future space-based missions such as JWST and EChO. I acknowledge generous support from the Zwicky Prize Fellowship and the Star and Planet Formation Group (PI: Michael Meyer) at ETH Zurich.

  18. JUPITER PROJECT - JOINT UNIVERSAL PARAMETER IDENTIFICATION AND EVALUATION OF RELIABILITY

    Science.gov (United States)

    The JUPITER (Joint Universal Parameter IdenTification and Evaluation of Reliability) project builds on the technology of two widely used codes for sensitivity analysis, data assessment, calibration, and uncertainty analysis of environmental models: PEST and UCODE.

  19. How does stellar irradiation make hot Jupiters puffy?

    Science.gov (United States)

    Wei, Yu-Jie; Gu, Pin-Gao

    2017-06-01

    Hot Jupiters appear to be re-inflated as their host stars evolve and become more luminous, shedding more light on the intriguing correlation between stellar irradiation and the size of hot Jupiters. To account for the phenomenon, one of the well-known models is the thermal-tide scenario proposed by Arras and Socrates. We present a linear analysis of semi-diurnal thermal tides in a hot Jupiter. The Coriolis effect is added to our equation, which generates more wave modes than non-rotating models, such as Rossby, Yanai, and inertial waves. We attempt to investigate where and which mode contributes most of the torque that maintains the planet in an asynchronous state against gravitational tides, leading to re-inflation of a hot Jupiter.

  20. Fitting Orbits to Jupiter's Moons with a Spreadsheet.

    Science.gov (United States)

    Bridges, Richard

    1995-01-01

    Describes how a spreadsheet is used to fit a circular orbit model to observations of Jupiter's moons made with a small telescope. Kepler's Third Law and the inverse square law of gravity are observed. (AIM)