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  • LPI 40th Anniversary - 2008
    Former astronaut and U S senator Dr Harrison Jack Schmitt Former directors Dr Robert Pepin Dr James Head and Dr Roger Phillips Former staff scientists Dr Renu Malhotra Dr Peter Schultz and Dr James Zimbelman Former deputy director and current staff scientist Dr Paul Spudis Former visiting scientists Dr G Jeffrey Taylor and Dr Christian Koeberl Former intern Dr Jonathan Lunine As we look back with fond memories at the

    Original URL path: http://www.lpi.usra.edu/lpi_40th/2008.shtml (2016-02-15)
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  • Scientific Staff
    Constantin Sandu Dr Susanne Schwenzer Dr Stephanie Shipp Dr Yann Sonzogni Dr Kyusei Tsuno Dr Faith Vilas Dr Oliver White Dr Axel Wittmann Postdoctoral Fellows Dr Patricia Craig Dr Jangmi Han Dr Nicolas Le Corvec Dr Martin Schmieder Dr Francesca Scipioni Dr Barry Shaulis Scientists in Residence During the Last Five Years Dr Oleg Abramov Dr Emily CoBabe Amman Dr Stephen Baloga Dr Yolanda Cedillo Flores Dr Qi Fu Dr Erica Jawan Dr Katherine Joy Dr Keiji Misawa Dr Amanda Nahm Dr Minako Righter Dr Tomohiro Usui Dr Channon Visscher Scientific Staff listed by Areas of Research ASTEROIDS AND COMETS Dr Jeremie Lasue Cometary nuclei interplanetary dust particles and Martian subsurface EARTH Dr Gerald Galgana Interactions of volcanoes and the lithosphere on terrestrial planets Dr David A Kring Dr Nicolas Le Corvec Dr Patrick J McGovern Structure and spreading of large volcanoes Dr Martin Schmieder Dr Susanne P Schwenzer Modeling of minerals formed in impact generated hydrothermal systems Dr Virgil Sharpton Dr Allan H Treiman MARS Ms Nancy Ann Budden Earth analogs for Mars missions with a focus on efforts defining the Mars surface science mission Dr Paul Byrne Dr Stephen M Clifford Nature and evolution of the hydrosphere Dr Walter S Kiefer Thermal and volcanic evolution gravity models Dr David A Kring Dr Jeremie Lasue Cometary nuclei interplanetary dust particles and Martian subsurface Dr Nicolas Le Corvec Dr Stephen Mackwell Experimental rheology and mineral physics Dr Patrick J McGovern Volcanism tectonism thermal evolution hemispheric dichotomy Dr Kevin Righter Experimental mineralogy and petrology Dr Mark Robinson Origin and evolution of planetary crusts including volcanism tectonism and regolith development Dr Constantin Sandu Dr Susanne P Schwenzer Modeling of minerals formed in impact generated hydrothermal systems Dr Allan H Treiman Geology and geochemistry of Mars meteorites MERCURY Dr Paul Byrne Dr Mark

    Original URL path: http://www.lpi.usra.edu/science/staff/ (2016-02-15)
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  • Staff Highlights Archive
    July June May April March February January 2014 December October August July May April January 2013 September August July June May April March February January 2012 November October September August July June May March 2011 July May April March February

    Original URL path: http://www.lpi.usra.edu/science/highlights/archive/ (2016-02-15)
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  • Schrodinger Basin: Mission Concepts
    walls will provide a cross section through a substantial portion of the lunar crust Furthermore the bulk composition of that crust can be derived from the composition of the Schrödinger impact melt Collectively those samples provide a means for testing the lunar magma ocean hypothesis A Scientifically rich Exploration Site Magmas eventually erupted onto the basin floor producing mare basalt flows and a spectacular pyroclastic vent providing an opportunity to probe the thermal and magmatic evolution of the Moon s mantle Landing Sites The pyroclastic vent may have important in situ resource ISRU potential too producing volatile deposits and fine grained material that is easily excavated transported and processed for a sustainable exploration effort by either robotic assets or human crews Thus far four landing sites have been identified for human missions three landing sites have been identified for robotic or human assisted robotic missions and other options are being located as more detailed geologic studies are produced Potential Mission Concepts To adequately address the lunar objectives of the National Research Council report sample return missions are required The best results would be obtained by a trained crew on the lunar surface Unfortunately we do not currently have the capability of landing crew on the surface so efforts to provide an alternative architecture using integrated robotic and human capability are being investigated One plan suggests deploying robotic assets to Schrödinger basin and teleoperating them with a crew hovering above the lunar farside at the Earth Moon L2 position in the Orion Multi Purpose Crew Vehicle The robotic asset could conduct geologic reconnaissance collect samples and return them to Earth In that same mission or a complementary mission the robotic assistant could deploy a low radio frequency telescope to address astrophysical science objectives The Moon s Schrödinger basin is the best

    Original URL path: http://www.lpi.usra.edu/science/schrodinger/ (2016-02-15)
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  • Dawn at Vesta
    per pixel shows a wide swath of equatorial Vesta including several of the large broad troughs that encircle the asteroid These troughs are 10 to 30 kilometers across and formed when Vesta underwent a period of extension likely associated with the formation of the large impact basins at the south pole Cornelia Crater This 12 kilometer wide impact crater may be the most recently formed large impact crater on all of Vesta These three views show from left to right high resolution global mosaic at 20 meter resolution color mapping at 70 meter resolution and topographic mapping at 70 meter resolution These data highlight some of the richness of the Dawn data set The reddish and purplish colors may be associated with OH bonds in the minerals and rocks consistent with hydration of some materials on Vesta whether these are inherent to Vesta or brought in by meteorites is not yet resolved Irregular pits within the small central floor deposit are likely due to gas exsolution in the impact melt deposits producing outgassing as the melt solidified Ejecta and flow within the ejecta can be seen to the south and south east Marcia Crater At 60 by 72 kilometers this oblong crater is the largest intact and well preserved crater on Vesta that post dates the giant South Pole basins It is rich in detail Impact melt flows and ponds are visible around the rim especially at a Small debris slides form a ring of narrow fingers along parts of the crater rim b exposing dark and bright materials within the crust of Vesta The sloping rim wall of Marcia is covered in thin impact melt and debris flows c The flat floor features numerous irregular outgassing pits and a small putative central peak at crater center Paul Schenk s

    Original URL path: http://www.lpi.usra.edu/science/dawn_at_vesta/ (2016-02-15)
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  • Terrestrial Planets: The Cratering Process
    Tranquillitatis basins 10 E 10 N to 35 E 30 N Albedo and elevation data were derived from Lunar Reconnaissance Orbiter iron and titanium data are from the Clementine mission All data have a nominal resolution of 100 m pixel Characterizing Crater Ejecta to Understand Lunar Mare Stratigraphy Principal Component Analysis The first three principal components were calculated from the albedo FeO and TiO2 data to minimize redundancy and accentuate distinguishing characteristics that may reveal geologically relevant information This image is a perspective view of the first principal component draped on elevation data with a 15 vertical exaggeration This image clearly differentiates highlands areas in violet magenta from high TiO2 basalts HTB areas in orange yellow and low TiO2 basalts LTB areas in green cyan Results The 42 km Plinius crater and the 18 km Dawes crater both appear to have excavated through the HTB layer and ejected LTB Crater scaling relations therefore suggest that the HTB surface unit is less than 1 km thick Haughton Impact Structure Canada A Peak Ring Crater Location The 20 km Haughton structure is located at 89 7 W 75 4 N on Devon Island in the Arctic Archipelago of Canada Haughton Impact Structure Canada A Peak Ring Crater Geology The target rocks consist of a nearly flat lying sequence of platform sediments The lake that filled the Haughton crater deposited sediments TH on top of the original crater floor including TIB The base of the remaining lake deposits therefore preserves the original morphology of the Haughton crater Haughton Impact Structure Canada A Peak Ring Crater Topography reveals that the uplifted shatter coned Eleanor River outcrops OE near the basin center extend above the lake beds flanking them Therefore the OE outcrops represent a true central peak or peak ring Haughton Impact Structure Canada A Peak Ring Crater The TH breccias contain crystalline rock fragments indicating excavation through the 2 km thick platform sequence Preservation of OE outcrops however constrains the areal extent of this zone of deep excavation The OE exposures therefore appear to mark the boundary between deep and shallow excavation suggesting that they represent a poorly formed central peak ring Morphological Reconstruction of the Terny Impact Structure Central Ukraine The 280 million year old Terny impact structure formed in Precambrian rocks of the Ukrainian Shield The structure has been modified by erosion and subsequently buried by recent sediments Fig 1 Location of Terny Impact Structure in central Ukraine Morphological Reconstruction of the Terny Impact Structure Central Ukraine Fig 2 Photograph of iron mine near Terny ca 1900 Steeply dipping Precambrian crystalline rocks tan are overlain by 25 m of recent sediments Morphological Reconstruction of the Terny Impact Structure Central Ukraine Although there are no natural outcrops of the deformed basement rocks within the area mining exploration has provided surface and subsurface access to the structure exposing impact melt rocks shocked parautochthonous target rocks and allogenic impact breccias including suevites Fig 3 Color satellite image covering our study area annotated to show

    Original URL path: http://www.lpi.usra.edu/science/terrestrialPlanets/ (2016-02-15)
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  • Structure and Evolution of Planetary Volcanoes
    stresses at the top of the stiffer mantle s This compressional high stress zone also traps magma near the base of the crust thereby explaining the seismically observed thickening from below underplating of Hawaiian volcanos Giant Volcano Landslides on Earth and Mars A color map of topography of the island of Oahu and bathymetry of the submarine Nuuanu slide identifying potential analogs to structures in the Olympus Mons aureole black and white images further below The prominent Tuscaloosa Seamount label 1 in color bathymetry has dimensions very similar to large blocks in the north lobe of the Olympus Mons aureole image b label 1 A close up of the block shows lineations that resemble the raised margins of lava flows on the Olympus Mons edifice thereby establishing a link between the block and the edifice that strongly points Giant Volcano Landslides on Earth and Mars A topographic rendering of the massive north aureole lobe of Olympus Mons is flanked by similar renderings for Hawaiian volcanos the submarine Nuuanu slide north of Oahu left and the Hilina slump of the south flank of Kilauea volcano on the big island of Hawaii right The insets in the central figure show the Hawaiian examples at the same scale as Olympus Mons The Olympus Mons north aureole is about 30 times the volume of the Nuuanu slide comparable to the volume difference between the Olympus Mons main edifice and a Hawaiian island However note that the sizes of individual aureole blocks are similar to those constituting the Hawaiian landslides suggesting that the planet independent strength of basaltic rocks plays a role in determining block size Olympus Mons East Flank Olympus Mons the tallest volcano in the solar system at 23 km from base to summit is located on the flank of the immense Tharsis

    Original URL path: http://www.lpi.usra.edu/science/PlanetaryVolcanos/ (2016-02-15)
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  • Discovery: Icy Satellites
    ring Gilgamesh basin is the largest fully preserved impact feature on Ganymede Unlike Odysseus this 600 kilometer wide crater is less than 2 kilometers deep due to the much higher internal heat flow of Ganymede inducing ice flow in the icy crust Ganymede The ancient dark terrains of Ganymede are geologically complex This view has been colorized with topographic information where blues are low terrain and reds are high terrain Originally formed more than 4 billion yearsago linear fault systems smooth deposts and impact craters have completely reshaped the landscape Many of the craters have also been relaxed and are much shallower than originally formed Total relief across this 400 kilometer wide scene is only 2 kilometers Io The highest mountains in the outer solar system and some of the highest in the entire solar system are found on rocky volcanic Io the innermost moon of Jupiter This view shows the center of Tohil Mons a 9 kilometer high massif observed by the Galileo spacecraft Mountains like these are probably large crustal blocks forced upward by deep compression within the thick volcanic crust The dark circular areas are active basaltic calderas The Voyager Galileo and ongoing Cassini missions have been

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