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  • Kring Named as Fellow of the Geological Society of America
    has also studied the environmental effects of impact cratering and shown how impact processes can affect both the geological and biological evolution of a planet This work includes studies of the dramatic environmental perturbations e g prolonged darkness acid rain wildfires expected after the Chicxulub impact event plus studies of several smaller local regional and global effects produced by the thousands of impact events that affected Earth after life evolved Kring has also explored how impact cratering may have affected the early evolution of the Earth Moon system In particular he has led a decade long campaign to test the lunar cataclysm hypothesis which is one of the great intellectual legacies of the Apollo program Indeed the bombardment of the Earth Moon system remains the highest science priority for our nation s return to the Moon Kring has suggested that an intense period of impact bombardment may have affected the origin and early evolution of life on Earth In particular he suggested that early impact bombardment created vast subsurface hydrothermal systems that were crucibles for prebiotic chemistry and provided habitats for the early evolution of life He calls this concept the impact origin of life hypothesis GSA Fellowship is an

    Original URL path: http://www.lpi.usra.edu/features/kring/ (2016-02-15)
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  • Back to the Future: Space Shuttle Shows Tunguska Explosion was Caused by a Comet
    the atmosphere by the comet s icy nucleus was caught up in swirling eddies with tremendous energy by a process called two dimensional turbulence which explains why the noctilucent clouds formed a day later many thousands of miles away Noctilucent clouds are the Earth s highest clouds forming naturally in the mesosphere at about 55 miles over the polar regions during the summer months when the mesosphere is around 180 F 117 C The space shuttle exhaust plume the researchers say resembled the comet s action A single space shuttle flight injects 300 metric tons of water vapor into Earth s thermosphere and the water particles have been found to travel to the Arctic and Antarctic regions where they form the clouds after settling into the mesosphere Kelley and collaborators saw the noctilucent cloud phenomenon days after the space shuttle Endeavour STS 118 launched on August 8 2007 Similar cloud formations had been observed following launches in 1997 and 2003 Following the 1908 explosion known as the Tunguska Event the night skies shone brightly for several days across Europe particularly Great Britain more than 3000 miles away Kelley said he became intrigued by the historical eyewitness accounts of the aftermath and concluded that the bright skies must have been the result of noctilucent clouds The comet would have started to break up at about the same altitude as the release of the exhaust plume from the space shuttle following launch In both cases water vapor was injected into the atmosphere The scientists have attempted to answer how this water vapor traveled so far without scattering and diffusing as conventional physics would predict There is a mean transport of this material for tens of thousands of kilometers in a very short time and there is no model that predicts that Kelley

    Original URL path: http://www.lpi.usra.edu/features/tunguska/ (2016-02-15)
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  • NASA Scientists Bring Light to Moon’s Permanently Dark Craters
    as they target for an encounter with a permanently dark crater near the lunar south pole Since the beginning of time these lunar craters have been invisible to humanity said Barbara Wilson a scientist at JPL and manager of the study Now we can see detailed topography inside these craters down to 40 meters 132 feet per pixel with height accuracy of better than 5 meters 16 feet Full resolution versions of the images are available at NASA Mission News Scientists targeted the Moon s south polar region using Goldstone s 70 meter 230 foot radar dish The antenna three quarters the size of a football field sent a 500 kilowatt strong 90 minute long radar stream 373 046 kilometers 231 800 miles to the Moon Signals were reflected back from the rough hewn lunar terrain and detected by two of Goldstone s 34 meter 112 foot antennas on Earth The roundtrip time from the antenna to the Moon and back was about two and a half seconds The scientists compared their data with laser altimeter data recently released by the Japanese Aerospace Exploration Agency s Kaguya mission to position and orient the radar images and maps The new map

    Original URL path: http://www.lpi.usra.edu/features/lunar/southPolar/ (2016-02-15)
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  • Lunar Mission Launches, Successfully Enters Moon Orbit
    powering up the components necessary to control the spacecraft The satellite will relay more information about the lunar environment than any other previous mission to the Moon During transit to the Moon engineers performed a mid course correction to get the spacecraft in the proper position to reach its lunar destination Since the Moon is always moving the spacecraft shot for a target point ahead of the Moon When close to the Moon LRO used its rocket motor to slow down until the gravity of the Moon caught the spacecraft in lunar orbit Lunar orbit insertion is a crucial milestone for the mission said Cathy Peddie LRO deputy project manager at Goddard The LRO mission cannot begin until the Moon captures us Once we enter the Moon s orbit we can begin to buildup the dataset needed to understand in greater detail the lunar topography features and resources We are so proud to be a part of this exciting mission and NASA s planned return to the Moon A series of four engine burns over the next few days will put the satellite into its commissioning phase orbit During the commissioning phase each of its seven instruments is checked out and brought online The commissioning phase will end approximately 60 days after launch when LRO will use its engines to transition to its primary mission orbit For its primary mission LRO will orbit above the Moon at about 31 miles 50 kilometers for one year The spacecraft s instruments will help scientists compile high resolution three dimensional maps of the lunar surface and also survey it at many spectral wavelengths The satellite will explore the Moon s deepest craters examining permanently sunlit and shadowed regions and provide understanding of the effects of lunar radiation on humans LRO will return more

    Original URL path: http://www.lpi.usra.edu/features/lunar/lro/launch/ (2016-02-15)
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  • NASA Selects Student’s Entry as New Mars Rover Name
    in our next generation of explorers said Mark Dahl the mission s program executive at NASA Headquarters Many of the nominating essays were excellent and several of the names would have fit well I am especially pleased with the choice which recognizes something universally human and essential to science Ma decided to enter the rover naming contest after she heard about it at her school I was really interested in space but I thought space was something I could only read about in books and look at during the night from so far away Ma said I thought that I would never be able to get close to it so for me naming the Mars rover would at least be one step closer Curiosity is an everlasting flame that burns in everyone s mind It makes me get out of bed in the morning and wonder what surprises life will throw at me that day Ma wrote in her winning essay Curiosity is such a powerful force Without it we wouldn t be who we are today Curiosity is the passion that drives us through our everyday lives We have become explorers and scientists with our need to ask questions and to wonder The naming contest was conducted in partnership with Disney Pixar s animated film WALL E The activity invited ideas from students 5 18 years old enrolled in a U S school The contest started in November 2008 Entries were accepted until midnight on January 25 Walt Disney Studios Motion Pictures supplied the prizes for the contest including 30 for semifinalists related to WALL E Nine finalists have been invited to provide messages to be placed on a microchip mounted on Curiosity The microchip also will contain the names of thousands of people around the world who have

    Original URL path: http://www.lpi.usra.edu/features/mars/roverName/ (2016-02-15)
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  • NASA Study Shows Asteroids May Have Accelerated Life on Earth
    the heating of Earth by the bombardment Results from their project show that while the late heavy bombardment might have generated enough heat to sterilize Earth s surface microbial life in subsurface and underwater environments almost certainly would have survived Exactly when life originated on Earth is a hotly debated topic said Michael H New the astrobiology discipline scientist and manager of the Exobiology and Evolutionary Biology Program at NASA Headquarters These findings are significant because they indicate that if life had begun before the LHB or some time prior to 4 billion years ago it could have survived in limited refuges and then expanded to fill our world Our new results point to the possibility life could have emerged about the same time that evidence for our planet s oceans first appears said Mojzsis principal investigator of the project A growing scientific consensus is that during our solar system s formation planetary bodies were pummeled by debris throughout the late heavy bombardment A visual record of the event is preserved in the form of the scarred face of our Moon On Earth all traces of the bombardment appear to have been erased by rock recycling forces like weathering volcanos or other conditions that cause the crust to move or change Surface habitats for microbial life on early Earth would have been destroyed repeatedly by the bombardment However at the same time impacts could have created subsurface habitats for life such as extensive networks of cracks or even hydrothermal vents Any existing microbial life on Earth could have found refuge in these habitats If life had not yet emerged on Earth by the time of the bombardment these new subsurface environments could have been the place where terrestrial life emerged Even under the most extreme conditions we imposed on our

    Original URL path: http://www.lpi.usra.edu/features/asteroids/ (2016-02-15)
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  • MESSENGER Spacecraft Reveals a Very Dynamic Planet Mercury
    activity The spacecraft also made the first detection of magnesium in Mercury s thin atmosphere known as an exosphere This observation and other data confirm that magnesium is an important constituent of Mercury s surface materials The probe s Mercury Atmospheric and Surface Composition Spectrometer instrument detected the magnesium Finding magnesium was not surprising to scientists but seeing it in the amounts and distribution observed was unexpected The instrument also measured other exospheric constituents including calcium and sodium This is an example of the kind of individual discoveries that the science team will piece together to give us a new picture of how the planet formed and evolved said William McClintock co investigator and lead author of one of the four papers McClintock who is from the Laboratory for Atmospheric and Space Physics at the University of Colorado at Boulder suspects that additional metallic elements from the surface including aluminum iron and silicon also contribute to the exosphere The variability that the spacecraft observed in Mercury s magnetosphere the volume of space dominated by the planet s magnetic field so far supports the hypothesis that the great day to day changes in Mercury s atmosphere may be a result of changes in the shielding provided by the magnetosphere The spacecraft observed a radically different magnetosphere at Mercury during its second flyby compared with its earlier January 14 encounter said James Slavin from NASA s Goddard Space Flight Center Slavin is a mission co investigator and lead author of one of the papers During the first flyby important discoveries were made but scientists didn t detect any dynamic features The second flyby witnessed a totally different situation The spacecraft s discovery of the impact basin called Rembrandt is the first time scientists have seen terrain well exposed on the floor of a large impact basin on Mercury Landforms such as those revealed on the floor of Rembrandt usually are buried completely by volcanic flows This basin formed about 3 9 billion years ago near the end of the period of heavy bombardment of the inner solar system said Thomas Watters from the Smithsonian Institution in Washington a participating scientist and lead author of one paper Although ancient the Rembrandt basin is younger than most other known impact basins on Mercury Half of Mercury was unknown until a little more than a year ago Globes of the planet were blank on one side Spacecraft images have enabled scientists to see 90 of the planet s surface at high resolution The spacecraft s nearly global imaging coverage of the surface after the second flyby gives scientists fresh insight into how the planet s crust was formed After mapping the surface we see that approximately 40 is covered by smooth plains said Brett Denevi of Arizona State University in Tempe a team member and lead author of a paper Many of these smooth plains are interpreted to be of volcanic origin and they are globally distributed Much of Mercury s crust may have formed

    Original URL path: http://www.lpi.usra.edu/features/messenger/05012009/ (2016-02-15)
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  • Mars Spacecraft Teams on Alert for Dust-Storm Season
    cameras toward the Sun to check the clarity of the atmosphere virtually every day These measurements let the planning team estimate how much energy the rovers will have available on the following day Observations of changes in the martian atmosphere by NASA s Mars Reconnaissance Orbiter which reached Mars in 2006 and NASA s Mars Odyssey which reached Mars in 2001 are available to supplement the rover s own skywatch The Mars Color Imager camera on Mars Reconnaissance Orbiter sees the entire planet every day at resolution comparable to weather satellites around Earth We can identify where dust is rising into the atmosphere and where it is moving from day to day said Michael Malin of Malin Space Science Systems in San Diego principal investigator for the Mars Color Imager Our historical baseline of observing martian weather including data from the Mars Global Surveyor mission from 1998 to 2007 helps us know what to expect Weather on Mars is more repetitive from year to year than weather on Earth Global dust events do not occur every Mars year but if they do occur they are at this time of year Two other instruments the Thermal Emission Imaging System on Mars Odyssey and the Mars Climate Sounder on Mars Reconnaissance Orbiter monitor changes in airborne dust or dust related temperatures in Mars upper atmosphere Orbiters also aid surface missions with radio relays imaging to aid drive plans and studies of possible future landing sites When orbital observations indicate a dust raising storm is approaching a rover the rover team can take steps to conserve energy For example the team can reduce the length of time the rover will be active or can shorten or delete some communication events In recent weeks frequent weather reports from Bruce Cantor of Malin s Mars

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