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  • Cracks in Pluto’s Moon Could Indicate it Once Had an Underground Ocean
    gas giant planets in the outer solar system have cracked surfaces with evidence for ocean interiors Jupiter s moon Europa and Saturn s moon Enceladus are two examples As Europa and Enceladus move in their orbits a gravitational tug of war between their respective parent planets and neighboring moons keeps their orbits from becoming circular Instead these moons have eccentric slightly oval shaped orbits which raise daily tides that flex the interior and stress the surface It is thought that tidal heating has extended the lifetimes of subsurface oceans on Europa and Enceladus by keeping their interiors warm In Charon s case this study finds that a past high eccentricity could have generated large tides causing friction and surface fractures The moon is unusually massive compared to its planet about one eighth of Pluto s mass a solar system record It is thought to have formed much closer to Pluto after a giant impact ejected material off the planet s surface The material went into orbit around Pluto and coalesced under its own gravity to form Charon and several smaller moons Initially there would have been strong tides on both worlds as gravity between Pluto and Charon caused their surfaces to bulge toward each other generating friction in their interiors This friction would have also caused the tides to slightly lag behind their orbital positions The lag would act like a brake on Pluto causing its rotation to slow while transferring that rotational energy to Charon making it speed up and move farther away from Pluto Depending on exactly how Charon s orbit evolved particularly if it went through a high eccentricity phase there may have been enough heat from tidal deformation to maintain liquid water beneath the surface of Charon for some time said Rhoden Using plausible interior structure

    Original URL path: http://www.lpi.usra.edu/features/new_horizons/062414/ (2016-02-15)
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  • NASA Experiments Recreate Aromatic Flavors of Titan
    The spectral signature of the material suggested it was made up of a mixture of molecules To investigate that mixture the researchers turned to the tried and true approach of combining gases in a chamber and letting them react The idea is that if the experiment starts with the right gases and under the right conditions the reactions in the lab should yield the same products found in Titan s smoggy atmosphere The process is like being given a slice of cake and trying to figure out the recipe by tasting it If you can make a cake that tastes like the original slice then you chose the right ingredients The challenge is that the possibilities are almost limitless in this case Titan s dirty orange color comes from a mixture of hydrocarbons molecules that contain hydrogen and carbon and nitrogen carrying chemicals called nitriles The family of hydrocarbons already has hundreds of thousands of members identified from plants and fossil fuels on Earth and more could exist The logical starting point was to begin with the two gases most plentiful in Titan s atmosphere nitrogen and methane But these experiments never produced a mixture with a spectral signature to match to the one seen by Cassini neither have similar experiments conducted by other groups Promising results finally came when the researchers added a third gas essentially tweaking the flavors in the recipe for the first time The team began with benzene which has been identified in Titan s atmosphere followed by a series of closely related chemicals that are likely to be present there All these gases belong to the subfamily of hydrocarbons known as aromatics The outcome was that best results were obtained when the scientists chose an aromatic that contained nitrogen When team members analyzed those lab

    Original URL path: http://www.lpi.usra.edu/features/cassini/062414/ (2016-02-15)
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  • NASA’s Mars Curiosity Rover Marks First Martian Year
    Mars Measurements of heavy vs light variants of elements in the martian atmosphere indicate that much of Mars early atmosphere disappeared by processes favoring loss of lighter atoms such as from the top of the atmosphere Other measurements found that the atmosphere holds very little if any methane a gas that can be produced biologically The first determinations of the age of a rock on Mars and how long a rock has been exposed to harmful radiation provide prospects for learning when water flowed and for assessing degradation rates of organic compounds in rocks and soils Curiosity paused in driving this spring to drill and collect a sample from a sandstone site called Windjana The rover currently is carrying some of the rock powder sample collected at the site for follow up analysis Windjana has more magnetite than previous samples we ve analyzed said David Blake principal investigator for Curiosity s Chemistry and Mineralogy CheMin instrument at NASA s Ames Research Center Moffett Field California A key question is whether this magnetite is a component of the original basalt or resulted from later processes such as would happen in water soaked basaltic sediments The answer is important to our understanding of habitability and the nature of the early Mars environment Preliminary indications are that the rock contains a more diverse mix of clay minerals than was found in the mission s only previously drilled rocks the mudstone targets at Yellowknife Bay Windjana also contains an unexpectedly high amount of the mineral orthoclase a potassium rich feldspar that is one of the most abundant minerals in Earth s crust that had never before been definitively detected on Mars This finding implies that some rocks on the Gale Crater rim from which the Windjana sandstones are thought to have been derived may have experienced complex geological processing such as multiple episodes of melting It s too early for conclusions but we expect the results to help us connect what we learned at Yellowknife Bay to what we ll learn at Mount Sharp said John Grotzinger Curiosity project scientist at the California Institute of Technology Pasadena Windjana is still within an area where a river flowed We see signs of a complex history of interaction between water and rock Curiosity departed Windjana in mid May and is advancing westward It has covered about nine tenths of a mile 1 5 kilometers in 23 driving days and brought the mission s odometer tally up to 4 9 miles 7 9 kilometers Since wheel damage prompted a slow down in driving in late 2013 the mission team has adjusted routes and driving methods to reduce the rate of damage For example the mission team revised the planned route to future destinations on the lower slope of an area called Mount Sharp where scientists expect geological layering will yield answers about ancient environments Before Curiosity landed scientists anticipated that the rover would need to reach Mount Sharp to meet the goal of determining whether the ancient

    Original URL path: http://www.lpi.usra.edu/features/mars_rover/062414/ (2016-02-15)
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  • LPI Releases New Impact Cratering Education Site
    slide sets and image gallery that are used at universities across the country a new series of video simulations of impact cratering processes has been developed for similar classroom use Video Simulations of Impact Cratering Processes explore how impactor size and velocity as well as target gravity and temperature affect the sizes and morphologies of impact craters The videos can be run in real time from the website or if

    Original URL path: http://www.lpi.usra.edu/features/impact_cratering/ (2016-02-15)
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  • High-Resolution Radar at Arecibo Observatory Reveals Asteroid As a Beauty, Not a Beast
    asteroid 2014 HQ124 are some of the most detailed images of a near Earth asteroid ever obtained with Arecibo Observatory and Goldstone Solar System Radar GSSR The images were taken on June 8 when asteroid 2014 HQ124 safely passed Earth a little over three times the distance from Earth to the Moon about 1 3 million kilometers or 800 000 miles Arecibo Observatory together with the GSSR observed HQ124 nine hours after the closest approach These radar observations show that the asteroid is a beauty not a beast said Alessondra Springmann a data analyst at Arecibo Observatory noting the complex structure of the asteroid and its peanut shape visible in the radar data Most radar experiments involve one radio telescope transmitting signal to the asteroid then receiving reflected radio waves from the asteroid Scientists observing asteroid 2014 HQ124 directed the 70 meter 230 foot GSSR also known as DSS 14 to transmit to the asteroid then the 305 meter 1000 foot Arecibo Observatory collected the reflected waves We used two telescopes because that combination allowed us to get images with twice as much detail as Arecibo could achieve otherwise said Lance Benner a scientist at the Jet Propulsion Laboratory who

    Original URL path: http://www.lpi.usra.edu/features/arecibo/061614/ (2016-02-15)
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  • Astronomers Confounded By Massive Rocky World
    is more than twice as large in size This discovery has planet formation theorists challenged to explain how such a world could have formed We were very surprised when we realized what we had found said astronomer Xavier Dumusque of the Harvard Smithsonian Center for Astrophysics Cambridge Massachusetts who led the analysis using data originally collected by NASA s Kepler space telescope Kepler 10c as the planet had been named had a previously measured size of 2 3 times larger than Earth but its mass was not known until now The team used the HARPS North instrument on the Telescopio Nazionale Galileo in the Canary Islands to conduct follow up observations to obtain a mass measurement of the rocky behemoth It was thought worlds such as this could not possibly exist The enormous gravitational force of such a massive body would accrete a gas envelope during formation ballooning the planet to a gas giant the size of Neptune or even Jupiter However this planet is thought to be solid composed primarily of rock Just when you think you ve got it all figured out nature gives you a huge surprise in this case literally said Natalie Batalha Kepler mission scientist

    Original URL path: http://www.lpi.usra.edu/features/kepler/060314/ (2016-02-15)
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  • Barringer Award Recipients Announced
    Albert Ludwigs Universität Freiburg Germany Anna Chanou University of Western Ontario Canada Agnese Fazio Università di Pisa Italy Erik S Heider Auburn University United States Pedro E Montalvo Jiménez University of Puerto Rico United States Mario Mustasaar University of Tartu Estonia Sarah Simpson University of Glasgow United Kingdom The Barringer Family Fund for Meteorite Impact Research was established to support field work by eligible students interested in the study of impact cratering processes The Fund provides a small number of competitive grants each year for support of field research at known or suspected impact sites worldwide The Barringer Family Fund has been established as a memorial to four of Daniel Moreau Barringer s sons Brandon Moreau or Reau as he was called Paul and Richard As the first person to identify the true origin of the Barringer Meteorite Crater aka Meteor Crater Daniel Moreau Barringer instilled a deep interest about the crater and its signficance to his sons Each of them in turn had a lifelong association with the crater and the field of meteoritics from its early beginnings In addition to its memorial nature the Fund also reflects the family s long standing commitment to responsible stewardship of The

    Original URL path: http://www.lpi.usra.edu/features/awards/barringer2014/ (2016-02-15)
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  • NASA Mars Weathercam Helps Find Large New Crater
    was looking for Cantor said I was doing my usual weather monitoring and something caught my eye It looked usual with rays emanating from a central spot He began examining earlier images skipping back a month or more at a time The images revealed that the dark spot was present a year ago but not five years ago He homed in further checking images from about 40 different dates and pinned down the date the impact event occurred the spot was not there up through March 27 2012 and then appeared before the daily imaging on March 28 2012 Once the dark spot was verified as new it was targeted last month by CTX and the orbiter s sharpest sighted camera the High Resolution Imaging Science Experiment HiRISE Of the approximately 400 fresh crater causing impacts on Mars that have been documented with before and after images this is the only one discovered using a MARCI image rather than an image from a higher resolution camera CTX has imaged nearly the entire surface of Mars at least once during the orbiter s seven plus years of observations It had photographed the site of this newly discovered crater in January 2012 prior to the impact Two craters appear in the April 2014 CTX image that were not present in the earlier one confirming the dark spot revealed by MARCI is related to a new impact crater HiRISE reveals more than a dozen smaller craters near the two larger ones seen in the CTX image possibly created by chunks of the exploding asteroid or secondary impacts of material ejected from the main craters during impact It also reveals many landslides that darkened slopes in the 5 mile surrounding area A second HiRISE image in May 2014 added three dimensional information The biggest

    Original URL path: http://www.lpi.usra.edu/features/mro/060314/ (2016-02-15)
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