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  • NASA Orbiter Reveals Big Changes in Mars’ Atmosphere
    other clues suggest the deposit is in a dissipating phase adding gas to the atmosphere each year Mars atmosphere is about 95 carbon dioxide in contrast to Earth s much thicker atmosphere which is less than 0 04 carbon dioxide We already knew there is a small perennial cap of carbon dioxide ice on top of the water ice there but this buried deposit has about 30 times more dry ice than previously estimated said Roger Phillips of Southwest Research Institute in Boulder Colorado Phillips is deputy team leader for the Mars Reconnaissance Orbiter s Shallow Radar instrument and lead author of the article We identified the deposit as dry ice by determining the radar signature fit the radio wave transmission characteristics of frozen carbon dioxide far better than the characteristics of frozen water said Roberto Seu of Sapienza University of Rome team leader for the Shallow Radar and a co author of the new report Additional evidence came from correlating the deposit to visible sublimation features typical of dry ice When you include this buried deposit martian carbon dioxide right now is roughly half frozen and half in the atmosphere but at other times it can be nearly all frozen or nearly all in the atmosphere Phillips said An occasional increase in the atmosphere would strengthen winds lofting more dust and leading to more frequent and more intense dust storms Another result is an expanded area on the planet s surface where liquid water could persist without boiling Modeling based on known variation in the tilt of Mars axis suggests several fold changes in the total mass of the planet s atmosphere can happen on time frames of 100 000 years or less The changes in atmospheric density caused by the carbon dioxide increase also would amplify some effects

    Original URL path: http://www.lpi.usra.edu/features/mars/mro/ (2016-02-15)
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  • Cassini Sees Saturn Electric Link With Enceladus
    magnetic field said Marcia Burton a Cassini fields and particles scientist at NASA s Jet Propulsion Laboratory It gives us the first visual connection between Saturn and one of its moons The auroral footprint measures approximately 1200 kilometers 750 miles by less than 400 kilometers 250 miles covering an area comparable to California or Sweden At its brightest the footprint shone with an ultraviolet light intensity far less than Saturn s polar auroral rings but comparable to the faintest aurora visible at Earth without a telescope in the visible light spectrum Scientists have not found a matching footprint at the southern end of the magnetic field line Jupiter s active moon Io creates glowing footprints near Jupiter s north and south poles so scientists suspected there was an analogous electrical connection between Saturn and Enceladus It is the only known active moon in the Saturn system with jets spraying water vapor and organic particles into space For years scientists used space telescopes to search Saturn s poles for footprints but they found none Cassini fields and particles instruments found particle beams aligned with Saturn s magnetic field near Enceladus and scientists started asking if we could see an expected ultraviolet spot at the end of the magnetic field line on Saturn said Wayne Pryor a lead author of the Nature article and Cassini co investigator at Central Arizona College We were delighted to find the glow close to the bulls eye at the center of our target In 2008 Cassini detected a beam of energetic protons near Enceladus aligned with the magnetic field and field aligned electron beams A team of scientists analyzed the data and concluded the electron beams had sufficient energy flux to generate a detectable level of auroral emission at Saturn A few weeks later Cassini captured

    Original URL path: http://www.lpi.usra.edu/features/cassini/042211/ (2016-02-15)
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  • SOFIA Completes First Flight of German Science Instrument
    engineers and technicians from the U S and Germany working together on an observatory developed in the U S using a telescope and instrument built in Germany to gather data of great interest to the entire world s scientific community said Bob Meyer NASA s SOFIA Program manager at NASA s Dryden Flight Research Center GREAT Principal Investigator Rolf Guesten of the Max Planck Institute for Radio Astronomy in Bonn Germany and his team conducted observations high above the central and western United States beginning the night of April 5 with their instrument installed on SOFIA s telescope Among their targets were IC 342 a spiral galaxy located 11 million light years from Earth in the constellation Camelopardalis The Giraffe and the Omega Nebula known as M17 5000 light years away in Sagittarius The team captured and analyzed radiation from ionized carbon atoms and carbon monoxide molecules to probe the chemical reactions motions of matter and flows of energy occurring in interstellar clouds Astronomers have evidence such clouds in both IC 342 and M17 are forming numerous massive stars These first spectra are the reward for the many years of work creating this technology and underline the scientific potential of airborne far infrared spectroscopy Guesten said GREAT focused on strong far infrared emissions from interstellar clouds that cool the clouds The balance between heating and cooling processes regulates the temperature of the interstellar material and controls initial conditions for the formation of new stars These observations give us unique information about the physical processes and chemical conditions in the stellar nurseries said Juergen Stutzki a co investigator on the GREAT team SOFIA will give us new and deep insight into how stars form GREAT one of two German first generation SOFIA scientific instruments was developed by the Max Planck Institute

    Original URL path: http://www.lpi.usra.edu/features/sofia/040711/ (2016-02-15)
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  • NASA Stardust Spacecraft Officially Ends Operations
    to planetary science said Lindley Johnson Stardust NExT and Discovery program executive at NASA Headquarters in Washington The treasure trove of science data and engineering information collected and returned by Stardust is invaluable for planning future deep space planetary missions After completion of the burn mission personnel began comparing the computed amount of fuel consumed during the engine firing with the anticipated amount based on consumption models The models are required to track fuel levels because there are no fully reliable fuel gauges for spacecraft in the weightless environment of space Mission planners use approximate fuel usage by reviewing the history of the vehicle s flight how many times and how long its rocket motors fired Stardust s motors burned for 146 seconds said Allan Cheuvront Lockheed Martin Space Systems Company program manager for Stardust NExT in Denver We ll crunch the numbers and see how close the reality matches up with our projections That will be a great data set to have in our back pocket when we plan for future missions Launched February 7 1999 Stardust flew past the asteroid Annefrank and traveled halfway to Jupiter to collect the particle samples from Comet Wild 2 The spacecraft returned to Earth s vicinity to drop off a sample return capsule eagerly awaited by comet scientists NASA re tasked the spacecraft as Stardust NExT to perform a bonus mission and fly past Comet Tempel 1 which was struck by the Deep Impact mission in 2005 The mission collected images and other scientific data to compare with images of that comet collected by the Deep Impact mission in 2005 Stardust traveled approximately 21 million kilometers 13 million miles around the Sun in the weeks after the successful Tempel 1 flyby The Stardust NExT mission met all mission goals and the spacecraft

    Original URL path: http://www.lpi.usra.edu/features/stardust/032511/ (2016-02-15)
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  • Center for Lunar Science and Exploration Welcomes 2011 Intern Class
    an opportunity to be involved in lunar exploration activities thus effectively training a new generation of space exploration leaders Working in teams the interns will identify sites on the Moon s surface where the nation s lunar science priorities can be accomplished with robotic and human exploration missions The 10 week program runs May 31 through August 5 2011 Applications were accepted from graduate students in geology planetary science and related programs as well as undergraduates with at least 50 semester hours of credit in those fields Now in its fourth year the program continues to produce successful outcomes Last year s interns submitted seven abstracts that were accepted for presentation at the 42nd Lunar and Planetary Science Conference Additionally the 2008 intern team recently published a peer reviewed paper that outlines the strategic advantages of a mission to the Schrödinger Basin on the Moon The Lunar Exploration Summer Intern Program is supported with funding from the LPI and the NASA Lunar Science Institute at NASA Ames Research Center Congratulations to the 10 students chosen to participate in this year s program David Blair Purdue University Sarah Crites University of Hawaii Myriam Lemelin Université de Sherbrooke Daniela Nowka Freie Universität

    Original URL path: http://www.lpi.usra.edu/features/lunar/intern2011/ (2016-02-15)
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  • Dawn Gets Vesta Target Practice
    Under the right conditions Vesta can be seen with binoculars But the best images so far from groundbased telescopes and Hubble still show Vesta as a bright mottled orb Once in orbit around Vesta Dawn will pass about 650 kilometers 400 miles above the asteroid s surface snapping multiangle images that will allow scientists to produce topographic maps Later Dawn will orbit at a lower altitude of about 200 kilometers 120 miles getting closer shots of parts of the surface The Dawn mission will have the capability to map 80 of the asteroid s surface in the year the spacecraft is in orbit around Vesta The north pole will be dark when Dawn arrives in July 2011 and is expected to be only dimly lit when Dawn leaves in July 2012 The mission will map Vesta at a spatial resolution on the order of the best global topography maps of Earth made by NASA s Shuttle Radar Topography mission Vesta formed very early in the history of the solar system and has one of the oldest surfaces in the system Scientists are eager to get their first close up look so they can better understand this early chapter Starting in August 2009 Dawn s optical navigation lead Nick Mastrodemos based at JPL developed a computer simulation of the orbits and images to be taken by the spacecraft He adapted software developed by Bob Gaskell of the Planetary Science Institute in Tucson Mastrodemos created a model using scientists best knowledge of Vesta and simulated the pictures that Dawn would take from the exact distances and geometries in the Dawn science plan He sent those images to two teams that use different techniques to derive topographical heights from imaging One led by Thomas Roatsch was based at the Institute of Planetary Research

    Original URL path: http://www.lpi.usra.edu/features/dawn/vesta/ (2016-02-15)
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  • 2011 LPI Summer Intern Program in Planetary ScienceJune 6, 2011–August 12, 2011
    very rewarding summer For more information about the program visit the summer intern webpage Student Rachel Barnett University of New Mexico Advisors John Jones and Dave Draper JSC Project Parental Liquid Composition of the Martian Meteorite NWS6162 Shergottite Student Kelly Nickodem University of Notre Dame Advisors Kevin Righter Lisa Danielson and Cin Ty Lee JSC Project Core Mantle Partitioning of Volatile Elements and the Origin of Volatiles in the Earth Student Kevin Michael Cannon Queen s University Advisor Brad Sutter JSC Project Sample Analysis on Mars SAM Instrument Data Base Development Evaluating Evolved Gas Release Interactions from the Thermal Decomposition of Volatile Bearing Mineral Mixtures Student Spenser Pantone Weber State University Advisor Paul Spudis LPI Project The Mini RF Experiment on the LRO Mission Fully Polarimetric SAR Images of the Moon Student Mattias Pär Karl Ek University of Gothenburg Advisor David Mittlefehldt JSC Project Investigation of Orthopyroxene Compositions in Diogenites Student Kathryn Elizabeth Powell Rice University Advisor Pat McGovern LPI Project Basin Ringing Olivines on the Moon What Are They and How Did They Get There Student Julia Gorman University of Rochester Advisors Julianne Gross and Allan Treiman LPI Project Discovery of Spinel Rich Rocks Mg Fe Al 2 O

    Original URL path: http://www.lpi.usra.edu/features/interns2011/ (2016-02-15)
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  • Some of Mars’ Missing Carbon Dioxide May be Buried
    smaller unnamed cratering event Observations in the high resolution mode of the Compact Reconnaissance Imaging Spectrometer for Mars CRISM instrument on the Mars Reconnaissance Orbiter show spectral characteristics of calcium or iron carbonate at this site Detections of clay minerals in lower resolution mapping mode by CRISM had prompted closer examination with the spectrometer and the carbonates are found near the clay minerals Both types of minerals typically form in wet environments The occurrence of this type of carbonate in association with the largest impact features suggests that it was buried by a few kilometers or miles of younger rocks possibly including volcanic flows and fragmented material ejected from other nearby impacts These findings reinforce a report by other researchers five months ago identifying the same types of carbonate and clay minerals from CRISM observation of a site about 1000 kilometers 600 miles away At that site a meteor impact has exposed rocks from deep underground inside Leighton crater In their report of that discovery Joseph Michalski of the Planetary Science Institute in Tucson and Paul Niles of NASA Johnson Space Center in Houston proposed that the carbonates at Leighton might be only a small part of a much more extensive ancient sedimentary record that has been buried by volcanic resurfacing and impact ejecta Carbonates found in rocks elsewhere on Mars from orbit and by NASA s Spirit rover are rich in magnesium Those could form from reaction of volcanic deposits with moisture Wray said The broader compositional range we re seeing that includes iron rich and calcium rich carbonates couldn t form as easily from just a little bit of water reacting with igneous rocks Calcium carbonate is what you typically find on Earth s ocean and lake floors He said the carbonates at Huygens and Leighton fit what

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