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  • Cassini Spacecraft Finds Ocean May Exist Beneath Titan’s Crust
    system said Ralph Lorenz lead author of the paper and Cassini radar scientist at the Johns Hopkins Applied Physics Laboratory Now we see changes in the way Titan rotates giving us a window into Titan s interior beneath the surface Members of the mission s science team used Cassini s Synthetic Aperture Radar to collect imaging data during 19 separate passes over Titan between October 2005 and May 2007 The radar can see through Titan s dense methane rich atmospheric haze detailing never before seen surface features and establishing their locations on the moon s surface Using data from the radar s early observations the scientists and radar engineers established the locations of 50 unique landmarks on Titan s surface They then searched for these same lakes canyons and mountains in the reams of data returned by Cassini in its later flybys of Titan They found prominent surface features had shifted from their expected positions by up to 30 kilometers 19 miles A systematic displacement of surface features would be difficult to explain unless the moon s icy crust was decoupled from its core by an internal ocean making it easier for the crust to move We believe that about 100 kilometers 62 miles beneath the ice and organic rich surface is an internal ocean of liquid water mixed with ammonia said Bryan Stiles of NASA s Jet Propulsion Laboratory Stiles is a contributing author to the paper The study of Titan is a major goal of the Cassini Huygens mission because it may preserve in deep freeze many of the chemical compounds that preceded life on Earth Titan is the only moon in the solar system that possesses a dense atmosphere The moon s atmosphere is 1 5 times denser than Earth s Titan is the largest of Saturn

    Original URL path: http://www.lpi.usra.edu/features/cassini/titan/ (2016-02-15)
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  • NASA Mission Finds New Clues to Guide the Search for Life on Mars
    from groundwater reaching the surface in low spots Osterloo said The water would evaporate and leave mineral deposits which build up over years The sites are disconnected so they are unlikely to be the remnants of a global ocean Scientists used Odyssey s Thermal Emission Imaging System a camera designed and operated by Arizona State University to take images in a range of visible light and infrared wavelengths Thermal infrared wavelengths are useful for identifying different mineral and rock types on the martian surface Osterloo found the sites by looking through thousands of images processed to reveal in false colors compositional differences on the martian surface Plotted on a Mars map the chloride sites appear only in the southern highlands the most ancient rocks on Mars Osterloo and seven co authors reported the findings in last week s issue of the journal Science Many of the deposits lie in basins with channels leading into them said Philip Christensen co author and principal investigator for the camera at Arizona State University This is the kind of feature like salt pan deposits on Earth that s consistent with water flowing in over a long time Scientists think the salt deposits formed approximately 3 5 to 3 9 billion years ago Several lines of evidence suggest Mars then had intermittent periods with substantially wetter and warmer conditions than today s dry frigid climate Scientists looking for evidence of past life on Mars have focused mainly on a handful of places that show evidence of clay or sulfate minerals Clays indicate weathering by water and sulfates may have formed by water evaporation The new research however suggests an alternative mineral target to explore for biological remains By their nature salt deposits point to a lot of water which potentially could remain standing in pools

    Original URL path: http://www.lpi.usra.edu/features/mars_odyssey/ (2016-02-15)
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  • Former LPI Intern Selected for Return to Moon Team
    topography to explore the lunar terrain for future landing sites Beyer will help plan stereo observations and build topographic models in order to study the geologic history of the Moon I haven t seen the reviews of my proposal yet Beyer said but I assume that I was selected because I can provide a variety of mission operations and science expertise to the team helping out with both the exploration and science portions of the mission The orbiter will conduct a one year primary mission exploring the Moon taking measurements to identify future robotic and human landing sites In addition it will study lunar resources and how the Moon s environment will affect humans The mission also will involve a spacecraft called the Lunar CRater Observation and Sensing Satellite LCROSS which will impact the lunar south pole to search for evidence of frozen polar water Instrument teams will define the science goals for the second year or what is deemed the extended science phase of the mission during its second year In addition to achieving its exploration objectives the LRO spacecraft is expected to return high quality scientific data such as day night temperature maps a global mapping system high resolution color imaging and detailed global topography that will greatly expand our understanding of the Moon NASA received a total of 55 proposals in response to a NASA Research Announcement released in 2007 A peer review panel and NASA Planetary Science Division Research and Analysis Program scientists evaluated the proposals Selection criteria included intrinsic merit relevance responsiveness to planetary science goals and objectives as well as cost Scientists will be fully or partially funded depending on their research work and scope of activities NASA will provide funding to U S scientists for up to three years depending on satisfactory progress

    Original URL path: http://www.lpi.usra.edu/features/beyer/ (2016-02-15)
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  • Saturn’s Moon Rhea Also May Have Rings
    3000 miles from the moon s center almost eight times the radius of Rhea Like finding planets around other stars and moons around asteroids these findings are opening a new field of rings around moons said Norbert Krupp a scientist with Cassini s Magnetospheric Imaging Instrument from the Max Planck Institute for Solar System Research Since the discovery Cassini scientists have carried out numerical simulations to determine if Rhea can maintain rings The models show that Rhea s gravity field in combination with its orbit around Saturn could allow rings that form to remain in place for a very long time The discovery was a result of a Cassini close flyby of Rhea in November 2005 when instruments on the spacecraft observed the environment around the moon Three instruments sampled dust directly The existence of some debris was expected because a rain of dust constantly hits Saturn s moons including Rhea knocking particles into space around them Other instruments observations showed how the moon was interacting with Saturn s magnetosphere and ruled out the possibility of an atmosphere Evidence for a debris disk in addition to this tenuous dust cloud came from a gradual drop on either side of Rhea in the number of electrons detected by two of Cassini s instruments Material near Rhea appeared to be shielding Cassini from the usual rain of electrons Cassini s Magnetospheric Imaging Instrument detected sharp brief drops in electrons on both sides of the moon suggesting the presence of rings within the disk of debris The rings of Uranus were found in a similar fashion by NASA s Kuiper Airborne Observatory in 1977 when light from a star blinked on and off as it passed behind Uranus rings Seeing almost the same signatures on either side of Rhea was the clincher added

    Original URL path: http://www.lpi.usra.edu/features/saturn/rhea/ (2016-02-15)
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  • Ancient Groundwater Flow on Mars
    in a Science article Fracture controlled Paleo Fluid Flow in Candor Chasma Mars that Treiman revived these old studies This work has always been in the back of my mind but it didn t seem that the community was interested said Treiman Treiman began refining his work until he was ready to once again present his findings He explains that the fault trace ridges which are over 100 kilometers long are the major terrain boundaries between the canyons Usually fault lines appear as valleys not ridges because the fault motions and earthquakes break up the rock For fault zones to appear to resist erosion and appear as ridges their broken rock must be cemented together On Earth the cements are usually minerals like silica and calcite deposited by flowing groundwater The length of the fault trace ridges up to and over 100 kilometers and their depth over 5 kilometers suggest that the faults acted as pipes for huge volumes of water The flow was probably west to east from the Tharsis volcanos and eventually downward toward Mars northern lowlands The fault trace ridges appear up to the surface of the nearby high plateaus which suggests that liquid water was stable

    Original URL path: http://www.lpi.usra.edu/features/mars_flows/ (2016-02-15)
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  • Results from Mercury, Moon Missions Highlight Conference
    topics at the South Shore Harbour Resort and Conference Center in League City Texas Media may register to attend Data from recent missions continue to offer space scientists worldwide new information and imagery to study On Jan 14 2008 MESSENGER was the first spacecraft to fly near Mercury in nearly 33 years MESSENGER has returned images of portions of the surface of Mercury never before seen by spacecraft and the first spacecraft measurements of the surface topography on the planet The major objectives of the Kaguya mission launched on Sept 14 2007 are to gather scientific data of the lunar origin and evolution and to develop the technology for future lunar exploration This continues to be an exciting era for planetary scientists Information from the diversity of missions returning new data every day complements the continuing discoveries in the planetary science research disciplines said Eileen Stansbery deputy director of the Astromaterials Research and Exploration Science Directorate at NASA s Johnson Space Center This year s conference provides much insight into the way the scientific community pulls diverse research disciplines and missions together to provide a framework for understanding our solar system and the bodies of which it is made Guest speakers include NASA Administrator Michael Griffin who will speak at 5 30 p m March 10 in Crystal Ballroom A Alan Stern associate administrator for NASA s Science Mission Directorate will hold a NASA Headquarters SMD Briefing at 12 10 p m March 12 in Crystal Ballroom A Jim Green director of NASA s Planetary Science Division will hold a NASA Headquarters SMD Exploration Systems Mission Directorate Briefing at 5 30 p m March 12 in Crystal Ballroom A The conference is put on by the Lunar and Planetary Institute LPI in partnership with the Johnson Space Center as part

    Original URL path: http://www.lpi.usra.edu/features/lpsc2008/messenger/ (2016-02-15)
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  • International Solar Mission to End Following Stellar Performance
    solar system and the discovery that the magnetic field leaving the Sun is balanced across latitudes The data and science output of this mission truly deserves to be named after the legendary explorer in Greek mythology said Arik Posner Ulysses program scientist at NASA Headquarters My compliments go out to the international team of scientists and engineers who built a spaceship and instrument payload that is highly sensitive yet durable enough that it withstood the most extreme conditions in the solar system including a polar passage of the giant planet Jupiter Since its Jupiter flyby in 1992 Ulysses has been in a six year orbit around the Sun Its long path through space carries it out to Jupiter s orbit and back The farther it ventures from the Sun the colder the spacecraft becomes If it drops to 2 C 36 F the spacecraft s hydrazine fuel will freeze This has not been a problem in the past because Ulysses carries heaters to maintain a workable onboard temperature The spacecraft is powered by the decay of a radioactive isotope Over its 17 plus years the power has been steadily dropping The spacecraft no longer can run all of its communications heating and scientific equipment simultaneously We expect certain parts of the spacecraft to reach 2 degrees Celsius pretty soon said Richard Marsden ESA project scientist and mission manager This temperature drop will block the fuel pipes making the spacecraft impossible to maneuver The NASA ESA project team approved a plan to temporarily shut off the main spacecraft s X band transmitter This would release 60 watts of power which could be channeled to the science instruments and the heater The team planned to turn the transmitter back on when data was to be transmitted back to Earth This would have

    Original URL path: http://www.lpi.usra.edu/features/ulysses/ (2016-02-15)
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  • Many, Perhaps Most, Nearby Sun-Like Stars May Form Rocky Planets
    m Warm dust can be traced at 24 m wavelengths Because dust closer to the star is hotter than dust farther from the star the warm dust likely traces material orbiting the star at distances comparable to the distance between Earth and Jupiter We found that about 10 to 20 percent of the stars in each of the four youngest age groups shows 24 micron emission due to dust Meyer said But we don t often see warm dust around stars older than 300 million years The frequency just drops off That s comparable to the timescales thought to span the formation and dynamical evolution of our own solar system he added Theoretical models and meteoritic data suggest that Earth formed over 10 to 50 million years from collisions between smaller bodies In a separate study Thayne Currie and Scott Kenyon of the Smithsonian Astrophysical Observatory in Cambridge Massachusetts and their colleagues also found evidence of dust from terrestrial planet formation around stars from 10 to 30 million years old These observations suggest that whatever led to the formation of Earth could be occurring around many stars between 3 million and 300 million years old Meyer said Kenyon and Ben Bromley of the University of Utah in Salt Lake City have developed planet formation models that provide a plausible scenario Their models predict warm dust would be detected at 24 m wavelengths as small rocky bodies collide and merge Our work suggests that the warm dust Meyer and colleagues detect is a natural outcome of rocky planet formation We predict a higher frequency of dust emission for the younger stars just as Spitzer observes said Kenyon The numbers on how many stars form planets are ambiguous because there s more than one way to interpret the Spitzer data Meyer said

    Original URL path: http://www.lpi.usra.edu/features/rocky_planets/ (2016-02-15)
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