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  • John Grunsfeld to Head NASA Science Directorate
    veteran of five space shuttle flights Grunsfeld visited Hubble three times as an astronaut performing a total of eight spacewalks to service and upgrade the observatory John s understanding of the critical connection between scientific research and the human exploration of space makes him an ideal choice for this job NASA Administrator Charles Bolden said I look forward to working with him to take the agency s science programs to even greater heights and make more of the groundbreaking discoveries about Earth and our universe for which NASA is known Grunsfeld graduated from the Massachusetts Institute of Technology in 1980 with a bachelor s degree in physics Returning to his native Chicago he earned a master s degree and in 1988 a doctorate in physics from the University of Chicago using a cosmic ray experiment on space shuttle Challenger for his doctoral thesis From Chicago he joined the faculty of the California Institute of Technology as a Senior Research Fellow in Physics Mathematics and Astronomy Grunsfeld joined NASA s Astronaut Office in 1992 He logged over 58 days in space on five shuttle missions including 58 hours and 30 minutes of spacewalk time He first flew to space onboard Endeavour in March 1995 on a mission that studied the far ultraviolet spectra of faint astronomical objects using the Astro Observatory His second flight was onboard Atlantis in January 1997 The mission docked with the Russian space station Mir and exchanged U S astronauts living onboard the outpost Grunsfeld then flew three shuttle missions onboard Discovery in December 1999 Columbia in March 2002 and Atlantis in May 2009 that successfully serviced and upgraded the Hubble Space Telescope He served as the payload commander on the 2002 mission and lead spacewalker in charge of Hubble activities on the 2009 flight In 2004

    Original URL path: http://www.lpi.usra.edu/features/grunsfeld/ (2016-02-15)
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  • NASA’s Kepler Confirms Its First Planet In Habitable Zone
    universe Kepler discovers planets and planet candidates by measuring dips in the brightness of more than 150 000 stars to search for planets that cross in front or transit the stars Kepler requires at least three transits to verify a signal as a planet Fortune smiled upon us with the detection of this planet said William Borucki Kepler principal investigator at NASA Ames Research Center who led the team that discovered Kepler 22b The first transit was captured just three days after we declared the spacecraft operationally ready We witnessed the defining third transit over the 2010 holiday season The Kepler science team uses groundbased telescopes and NASA s Spitzer Space Telescope to review observations on planet candidates the spacecraft finds The star field that Kepler observes in the constellations Cygnus and Lyra can only be seen from groundbased observatories in spring through early fall The data from these other observations help determine which candidates can be validated as planets Kepler 22b is located 600 light years away While the planet is larger than Earth its orbit of 290 days around a Sun like star resembles that of our world The planet s host star belongs to the same class as our Sun called G type although it is slightly smaller and cooler Of the 54 habitable zone planet candidates reported in February 2011 Kepler 22b is the first to be confirmed This milestone will be published in The Astrophysical Journal The Kepler team is hosting its inaugural science conference at Ames December 5 9 announcing 1094 new planet candidate discoveries Since the last catalog was released in February the number of planet candidates identified by Kepler has increased by 89 and now totals 2326 Of these 207 are approximately Earth sized 680 are super Earth sized 1181 are Neptune

    Original URL path: http://www.lpi.usra.edu/features/kepler/120611/ (2016-02-15)
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  • NASA’s Voyager Hits New Region at Solar System Edge
    18 billion kilometers from the Sun it is not yet in interstellar space In the latest data the direction of the magnetic field lines has not changed indicating Voyager is still within the heliosphere the bubble of charged particles the Sun blows around itself The data do not reveal exactly when Voyager 1 will make it past the edge of the solar atmosphere into interstellar space but suggest it will be in a few months to a few years The latest findings come from Voyager s Low Energy Charged Particle instrument Cosmic Ray Subsystem and Magnetometer Scientists previously reported the outward speed of the solar wind had diminished to zero in April 2010 marking the start of the new region Mission managers rolled the spacecraft several times this spring and summer to help scientists discern whether the solar wind was blowing strongly in another direction It was not Voyager 1 is plying the celestial seas in a region similar to Earth s doldrums where there is very little wind During this past year Voyager s magnetometer also detected a doubling in the intensity of the magnetic field in the stagnation region Like cars piling up at a clogged freeway off ramp the increased intensity of the magnetic field shows that inward pressure from interstellar space is compacting it Voyager has been measuring energetic particles that originate from inside and outside our solar system Until mid 2010 the intensity of particles originating from inside our solar system had been holding steady But during the past year the intensity of these energetic particles has been declining as though they are leaking out into interstellar space The particles are now half as abundant as they were during the previous five years At the same time Voyager has detected a 100 fold increase in

    Original URL path: http://www.lpi.usra.edu/features/voyager/120611/ (2016-02-15)
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  • New NASA Dawn Visuals Show Vesta’s ‘Color Palette’
    processes such as slumping that have modified the asteroid s surface Images from the visible and infrared mapping spectrometer reveal that the surface materials contain the iron bearing mineral pyroxene and are a mixture of rapidly cooled surface rocks and a deeper layer that cooled more slowly The relative amounts of the different materials mimic the topographic variations derived from stereo camera images indicating a layered structure that has been excavated by impacts The rugged surface of Vesta is prone to slumping of debris on steep slopes Dawn scientists presented the new images at the American Geophysical Union meeting in San Francisco on Monday December 5 The panelists included Vishnu Reddy framing camera team associate Max Planck Institute for Solar System Research Katlenburg Lindau Germany Eleonora Ammannito visible and infrared spectrometer team associate Italian Space Agency Rome and David Williams Dawn participating scientist Arizona State University Tucson Vesta s iron core makes it special and more like terrestrial planets than a garden variety asteroid said Carol Raymond Dawn s deputy principal investigator at NASA s Jet Propulsion Laboratory The distinct compositional variation and layering that we see at Vesta appear to derive from internal melting of the body shortly after

    Original URL path: http://www.lpi.usra.edu/features/dawn/120611/ (2016-02-15)
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  • Dawn Soars Over Asteroid Vesta in 3-D
    red right eye green blue the video incorporates images from Dawn s framing camera from July to August 2011 It was created by Dawn team member Ralf Jaumann of the German Aerospace Center DLR The images were obtained when Dawn was making its approach to Vesta and while orbiting the giant asteroid in its first science orbit survey orbit at an altitude of about 1700 miles 2700 kilometers The video begins with a global view of Vesta from the plane of its equator where a mysterious band of linear ridges and troughs can be seen The movie cuts to a flyover of young craters in the northern hemisphere whose peculiar alignment has led some scientists to refer to them as the snowman Then this virtual tour of Vesta takes the viewer around a massive mountain at the south pole of Vesta that is about 16 miles 25 kilometers high or more than twice the height of Mt Everest If you want to know what it s like to explore a new world like Vesta this new video gives everyone a chance to see it for themselves Jaumann said Scientists are poring over these images to learn more about how the craters hills grooves and troughs we see were created Vesta is the second most massive object in the asteroid belt between Mars and Jupiter Dawn is currently spiraling down to its low altitude mapping orbit which will bring the spacecraft to about 130 miles 210 kilometers above Vesta s surface Dawn s data thus far have revealed the rugged topography and complex textures of the surface of Vesta as can be seen in this video said Carol Raymond deputy principal investigator at NASA s Jet Propulsion Laboratory in Pasadena California Soon we ll add other pieces of the puzzle such

    Original URL path: http://www.lpi.usra.edu/features/dawn/120211/ (2016-02-15)
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  • Caltech-Led Team of Astronomers Finds 18 New Planets
    the theory that planets grow from seed particles that accumulate gas and dust in a disk surrounding a newborn star According to this theory tiny particles start to clump together eventually snowballing into a planet If this is the true sequence of events the characteristics of the resulting planetary system such as the number and size of the planets or their orbital shapes will depend on the mass of the star For instance a more massive star would mean a bigger disk which in turn would mean more material to produce a greater number of giant planets In another theory planets form when large amounts of gas and dust in the disk spontaneously collapse into big dense clumps that then become planets But in this picture it turns out that the mass of the star doesn t affect the kinds of planets that are produced So far as the number of discovered planets has grown astronomers are finding that stellar mass does seem to be important in determining the prevalence of giant planets The newly discovered planets further support this pattern and are therefore consistent with the first theory the one stating that planets are born from seed particles It s nice to see all these converging lines of evidence pointing toward one class of formation mechanisms Johnson says There s another interesting twist he adds Not only do we find Jupiter like planets more frequently around massive stars but we find them in wider orbits If you took a sample of 18 planets around Sun like stars he explains half of them would orbit close to their stars But in the cases of the new planets all are farther away at least 0 7 astronomical units from their stars One astronomical unit or AU is the distance from Earth to the Sun In systems with Sun like stars gas giants like Jupiter acquire close orbits when they migrate toward their stars According to theories of planet formation gas giants could only have formed far from their stars where it s cold enough for their constituent gases and ices to exist So for gas giants to orbit nearer to their stars certain gravitational interactions have to take place to pull these planets in Then some other mechanism perhaps the star s magnetic field has to kick in to stop them from spiraling into a fiery death The question Johnson says is why this doesn t seem to happen with so called hot Jupiters orbiting massive stars and whether that dearth is due to nature or nurture In the nature explanation Jupiter like planets that orbit massive stars just wouldn t ever migrate inward In the nurture interpretation the planets would move in but there would be nothing to prevent them from plunging into their stars Or perhaps the stars evolve and swell up consuming their planets Which is the case According to Johnson subgiants like the A stars they were looking at in this paper simply don t expand enough

    Original URL path: http://www.lpi.usra.edu/features/newPlanets/ (2016-02-15)
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  • NASA Launches Most Capable and Robust Rover to Mars
    technology and a sky crane touchdown to place Curiosity near the foot of a mountain inside Gale Crater on August 6 2012 During a nearly two year prime mission after landing the rover will investigate whether the region has ever offered conditions favorable for microbial life including the chemical ingredients for life The Atlas V initially lofted the spacecraft into Earth orbit and then with a second burst from the vehicle s upper stage pushed it out of Earth orbit into a 352 million mile 567 million kilometer journey to Mars Curiosity s ambitious science goals are among the mission s many differences from earlier Mars rovers It will use a drill and scoop at the end of its robotic arm to gather soil and powdered samples of rock interiors then sieve and parcel out these samples into analytical laboratory instruments inside the rover Curiosity carries 10 science instruments with a total mass 15 times as large as the science instrument payloads on the Mars rovers Spirit and Opportunity Some of the tools are the first of their kind on Mars such as a laser firing instrument for checking the elemental composition of rocks from a distance and an X ray diffraction instrument for definitive identification of minerals in powdered samples To haul and wield its science payload Curiosity is twice as long and five times as heavy as Spirit or Opportunity Because of its one ton mass Curiosity is too heavy to employ airbags to cushion its landing as previous Mars rovers could Part of the MSL spacecraft is a rocket powered descent stage that will lower the rover on tethers as the rocket engines control the speed of descent The mission s landing site offers Curiosity access for driving to layers of the mountain inside Gale Crater Observations

    Original URL path: http://www.lpi.usra.edu/features/MSL/ (2016-02-15)
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  • NASA Orbiter Captures Martian Sand Dunes in Motion
    not budge or moved too slowly for detection MRO was launched in 2005 Initial images from the spacecraft s High Resolution Imaging Science Experiment HiRISE camera documented only a few cases of shifting sand dunes and ripples collectively called bedforms Now after years of monitoring the martian surface the spacecraft has documented movements of a few yards or meters per year in dozens of locations across the planet The air on Mars is thin so stronger gusts of wind are needed to push a grain of sand Wind tunnel experiments have shown that a patch of sand would take winds of about 80 miles per hour nearly 130 kilometers per hour to move on Mars compared with only 10 miles per hour about 16 kilometers per hour on Earth Measurements from the meteorology experiments on NASA s Viking landers in the 1970s and early 1980s in addition to climate models showed such winds should be rare on Mars The first hints that martian dunes move came from NASA s Mars Global Surveyor which operated from 1997 to 2006 But the spacecraft s cameras lacked the resolution to definitively detect the changes NASA s Mars Exploration Rovers also detected hints of shifting sand when they touched down on the Red Planet s surface in 2004 The mission team was surprised to see grains of sand dotting the rovers solar panels They also witnessed the rovers track marks filling in with sand Sand moves by hopping from place to place said Matthew Golombek a co author of the paper and a member of the Mars Exploration Rover and Mars Reconnaissance Orbiter teams at NASA s Jet Propulsion Laboratory in Pasadena California Before the rovers landed on Mars we had no clear evidence of sand moving Not all of the sand on Mars

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