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  • NASA's Hubble Finds Pluto's Moons Tumbling in Absolute Chaos
    the University of Maryland at College Park appeared in the June 4 issue of the journal Nature Prior to the Hubble observations nobody appreciated the intricate dynamics of the Pluto system Showalter said Our research provides important new constraints on the sequence of events that led to the formation of the system Showalter also found three of Pluto s moons are presently locked together in resonance meaning there is a precise ratio for their orbital periods If you were sitting on Nix you would see that Styx orbits Pluto twice for every three orbits made by Hydra noted Hamilton Hubble data also reveal the moon Kerberos is as dark as a charcoal briquette while the other frozen moons are as bright as sand It was predicted that dust blasted off the moons by meteorite impacts should coat all the moons giving their surfaces a homogenous look which makes Kerberos coloring very surprising NASA s New Horizons spacecraft which will fly by the Pluto system in July may help settle the question of the asphalt black moon as well as the other oddities uncovered by Hubble These new discoveries are being used to plan science observations for the New Horizons flyby The turmoil within the Pluto Charon system offers insights into how planetary bodies orbiting a double star might behave For example NASA s Kepler space observatory has found several planetary systems orbiting double stars We are learning chaos may be a common trait of binary systems Hamilton said It might even have consequences for life on planets if found in such systems Clues to the Pluto commotion first came when astronomers measured variations in the light reflected off Nix and Hydra Analyzing Hubble images of Pluto taken from 2005 to 2012 scientists compared the unpredictable changes in the moons brightness

    Original URL path: http://www.lpi.usra.edu/features/061215/pluto/ (2016-02-15)
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  • NASA Instrument on Rosetta Makes Comet Atmosphere Discovery
    its various colors Scientists can identify the chemical composition of gases by examining their light spectrum Alice is the first such far ultraviolet spectrograph to operate at a comet Alice data indicate much of the water and carbon dioxide in the comet s coma originate from plumes erupting from its surface It is similar to those that the Hubble Space Telescope discovered on Jupiter s moon Europa with the exception that the electrons at the comet are produced by solar radiation while the electrons at Europa come from Jupiter s magnetosphere said Paul Feldman an Alice co investigator from the Johns Hopkins University in Baltimore Maryland By looking at the emission from hydrogen and oxygen atoms broken from the water molecules Alice scientists can actually trace the location and structure of water plumes from the surface of the comet The far ultraviolet region of the spectrum allows scientists to detect the most abundant elements in the universe hydrogen oxygen carbon and nitrogen However such measurements must be made from outside Earth s atmosphere either from orbiting observatories such as the Hubble Space Telescope or from planetary missions such as Rosetta From Earth orbit the atomic constituents can only be seen after their parent molecules such as water and carbon dioxide have been broken up by sunlight hundreds to thousands of kilometers or miles away from the nucleus of the comet The Alice spectrograph has also studied the surface of Comet 67P Churyumov Gerasimenko and will be used in further studies of its atmosphere as the comet approaches the Sun and its plumes become more active due to solar heating The comet observations will help scientists learn more about the origin and evolution of our solar system and the role comets may have played in providing Earth with water and perhaps

    Original URL path: http://www.lpi.usra.edu/features/061215/rosetta/ (2016-02-15)
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  • Mars Missions to Pause Commanding in June, Due to Sun
    restrictions on commanding such as using only reduced data rates or communicating only in an emergency during the days before and after that period Spacecraft will continue making some science observations during the conjunction period though rovers will not do any driving or arm movements Our overall approach is based on what we did for the solar conjunction two years ago which worked well said Nagin Cox a systems engineer at NASA s Jet Propulsion Laboratory Pasadena California who is leading conjunction planning for NASA s Curiosity Mars rover It is really helpful to have been through this before NASA s MAVEN spacecraft which arrived in Mars orbit last September will be experiencing its first solar conjunction Its team has prepared thoroughly MAVEN short for Mars Atmosphere and Volatile Evolution will continue monitoring the solar wind reaching Mars and making other measurements The data will be stored and transmitted back to us after communications are reestablished at the end of the solar conjunction period said James Morrissey MAVEN deputy project manager at NASA s Goddard Space Flight Center Greenbelt Maryland Transmissions from NASA s two other Mars orbiters Mars Odyssey and Mars Reconnaissance Orbiter will continue through the conjunction period but some of those transmissions are not expected to reach Earth Science data transmitted during conjunction will also remain stored aboard the orbiters for reliable retransmission in late June The active Mars rovers Curiosity and Opportunity will send limited data to orbiters throughout conjunction for relay to Earth during and after conjunction Mars Odyssey which reached Mars in 2001 will be in its seventh solar conjunction For Opportunity and Mars Reconnaissance Orbiter the 2015 solar conjunction is the sixth and fifth respectively In preparation for conjunction orbiter and Curiosity mission teams have been clearing some science data from spacecraft memories

    Original URL path: http://www.lpi.usra.edu/features/061215/mars/ (2016-02-15)
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  • Saturn Moon’s Activity Could Be ‘Curtain Eruptions’
    curtain eruptions from the tiger stripe fractures rather than intermittent geysers along them said Joseph Spitale lead author of the study and a participating scientist on the Cassini mission at the Planetary Science Institute in Tucson Arizona Some prominent jets likely are what they appear to be but most of the activity seen in the images can be explained without discrete jets In analyzing Cassini s images of the eruptions on Enceladus Spitale and colleagues took particular note of the faint background glow present in most images The brightest eruption features which appear to be discrete jets look to them to be superimposed intermittently upon this background structure The researchers modeled eruptions on Enceladus as uniform curtains along the tiger stripe fractures They found that phantom brightness enhancements appear in places where the viewer is looking through a fold in the curtain The folds exist because the fractures in Enceladus surface are more wavy than perfectly straight The researchers think this optical illusion is responsible for most of what appear to be individual jets The viewing direction plays an important role in where the phantom jets appear said Spitale If you rotated your perspective around Enceladus south pole such jets would seem to appear and disappear Phantom jets in simulated images produced by the scientists line up nicely with some of the features in real Cassini images that appear to be discrete columns of spray The correspondence between simulation and spacecraft data suggests that much of the discrete jet structure is an illusion according to the researchers Curtain eruptions occur on Earth where molten rock or magma gushes out of a deep fracture These eruptions which often create spectacular curtains of fire are seen in places such as Hawaii Iceland and the Galapagos Islands Our understanding of Enceladus continues to

    Original URL path: http://www.lpi.usra.edu/features/051415/cassini/ (2016-02-15)
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  • NASA’s Europa Mission Begins with Selection of Science Instruments
    science instruments includes cameras and spectrometers to produce high resolution images of Europa s surface and determine its composition An ice penetrating radar will determine the thickness of the moon s icy shell and search for subsurface lakes similar to those beneath Antarctica The mission also will carry a magnetometer to measure strength and direction of the moon s magnetic field which will allow scientists to determine the depth and salinity of its ocean A thermal instrument will scour Europa s frozen surface in search of recent eruptions of warmer water while additional instruments will search for evidence of water and tiny particles in the moon s thin atmosphere NASA s Hubble Space Telescope observed water vapor above the south polar region of Europa in 2012 providing the first strong evidence of water plumes If the plumes existence is confirmed and they re linked to a subsurface ocean it will help scientists investigate the chemical makeup of Europa s potentially habitable environment while minimizing the need to drill through layers of ice Last year NASA invited researchers to submit proposals for instruments to study Europa Thirty three were reviewed and of those nine were selected for a mission that will launch in the 2020s This is a giant step in our search for oases that could support life in our own celestial backyard said Curt Niebur Europa program scientist at NASA Headquarters in Washington We re confident that this versatile set of science instruments will produce exciting discoveries on a much anticipated mission The NASA selectees are Plasma Instrument for Magnetic Sounding PIMS principal investigator Dr Joseph Westlake of Johns Hopkins Applied Physics Laboratory APL Laurel Maryland This instrument works in conjunction with a magnetometer and is key to determining Europa s ice shell thickness ocean depth and salinity by correcting the magnetic induction signal for plasma currents around Europa Interior Characterization of Europa using Magnetometry ICEMAG principal investigator Dr Carol Raymond of NASA s Jet Propulsion Laboratory JPL Pasadena California This magnetometer will measure the magnetic field near Europa and in conjunction with the PIMS instrument infer the location thickness and salinity of Europa s subsurface ocean using multi frequency electromagnetic sounding Mapping Imaging Spectrometer for Europa MISE principal investigator Dr Diana Blaney of JPL This instrument will probe the composition of Europa identifying and mapping the distributions of organics salts acid hydrates water ice phases and other materials to determine the habitability of Europa s ocean Europa Imaging System EIS principal investigator Dr Elizabeth Turtle of APL The wide and narrow angle cameras on this instrument will map most of Europa at 164 foot 50 meter resolution and will provide images of areas of Europa s surface at up to 100 times higher resolution Radar for Europa Assessment and Sounding Ocean to Near surface REASON principal investigator Dr Donald Blankenship of the University of Texas Austin This dual frequency ice penetrating radar instrument is designed to characterize and sound Europa s icy crust from the near surface to

    Original URL path: http://www.lpi.usra.edu/features/052915/Europa/ (2016-02-15)
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  • Barringer Award Recipients Announced
    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

    Original URL path: http://www.lpi.usra.edu/features/052915/Barringer/ (2016-02-15)
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  • NASA’s New Horizons Detects Surface Features, Possible Polar Cap on Pluto
    unprocessed images beamed back to Earth New Horizons scientists interpreted the data to reveal the dwarf planet has broad surface markings some bright some dark including a bright area at one pole that may be a polar cap As we approach the Pluto system we are starting to see intriguing features such as a bright region near Pluto s visible pole starting the great scientific adventure to understand this enigmatic celestial object says John Grunsfeld associate administrator for NASA s Science Mission Directorate in Washington As we get closer the excitement is building in our quest to unravel the mysteries of Pluto using data from New Horizons Also captured in the images is Pluto s largest moon Charon rotating in its 6 4 day long orbit The exposure times used to create this image set a tenth of a second were too short for the camera to detect Pluto s four much smaller and fainter moons Since it was discovered in 1930 Pluto has remained an enigma It orbits our Sun about 5 billion kilometers more than 3 billion miles from Earth and researchers have struggled to discern any details about its surface These latest New Horizons images allow the mission science team to detect clear differences in brightness across Pluto s surface as it rotates After traveling more than nine years through space it s stunning to see Pluto literally a dot of light as seen from Earth becoming a real place right before our eyes said Alan Stern New Horizons principal investigator at Southwest Research Institute SwRI in Boulder Colorado These incredible images are the first in which we can begin to see detail on Pluto and they are already showing us that Pluto has a complex surface The images the spacecraft returns will dramatically improve as New

    Original URL path: http://www.lpi.usra.edu/features/051415/new_horizons/ (2016-02-15)
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  • NASA Research Reveals Europa’s Mystery Dark Material Could Be Sea Salt
    ocean below that would be a simple and elegant solution for what the dark mysterious material is said research lead Kevin Hand a planetary scientist at NASA s Jet Propulsion Laboratory JPL in Pasadena California One certainty is that Europa is bathed in radiation created by Jupiter s powerful magnetic field Electrons and ions slam into the moon s surface with the intensity of a particle accelerator Theories proposed to explain the nature of the dark material include this radiation as a likely part of the process that creates it Previous studies using data from NASA s Galileo spacecraft and various telescopes attributed the discolorations on Europa s surface to compounds containing sulfur and magnesium While radiation processed sulfur accounts for some of the colors on Europa the new experiments reveal that irradiated salts could explain the color within the youngest regions of the moon s surface To identify the dark material Hand and his co author Robert Carlson also at JPL created a simulated patch of Europa s surface in a laboratory test apparatus for testing possible candidate substances For each material they collected spectra which are like chemical fingerprints encoded in the light reflected by the compounds We call it our Europa in a can Hand said The lab setup mimics conditions on Europa s surface in terms of temperature pressure and radiation exposure The spectra of these materials can then be compared to those collected by spacecraft and telescopes For this particular research the scientists tested samples of common salt sodium chloride along with mixtures of salt and water in their vacuum chamber at Europa s chilly surface temperature of 173 C 280 F They then bombarded the salty samples with an electron beam to simulate the intense radiation on the moon s surface After a few

    Original URL path: http://www.lpi.usra.edu/features/051415/europa/ (2016-02-15)
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