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  • Cassini Sees the Two Faces of Titan’s Dunes
    they have formed and evolved Using radar data from the Cassini spacecraft Alice Le Gall a former postdoctoral fellow at NASA s Jet Propulsion Laboratory currently at the French research laboratory LATMOS in Paris and collaborators have discovered that the size of Titan s dunes is controlled by at least two factors altitude and latitude In terms of altitude the more elevated dunes tend to be thinner and more widely separated The gaps between the dunes seem to appear to Cassini s radar indicating a thinner covering of sand This suggests that the sand needed to build the dunes is mostly found in the lowlands of Titan Scientists think the sand on Titan is not made of silicates as on Earth but of solid hydrocarbons precipitated out of the atmosphere These have then aggregated into grains 0 04 inches in size by a still unknown process In terms of latitude the sand dunes on Titan are confined to its equatorial region in a band between 30 south latitude and 30 north latitude However the dunes tend to be less voluminous toward the north Le Gall and colleagues think that this may be due to Saturn s elliptical orbit Titan is in orbit around Saturn and so the moon s seasons are controlled by Saturn s path around the Sun Because Saturn takes about 30 years to complete an orbit each season on Titan lasts for about seven years The slightly elliptical nature of Saturn s orbit means that the southern hemisphere of Titan has shorter but more intense summers So the southern regions are probably drier which implies they have less ground moisture The drier the sand grains the more easily they can be transported by the winds to make dunes As one goes to the north we believe the

    Original URL path: http://www.lpi.usra.edu/features/cassini/012612/ (2016-02-15)
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  • Educators Selected to Fly on SOFIA Airborne Observatory
    astronomical research said John Gagosian SOFIA program executive at NASA Headquarters in Washington Working with astronomers educators participate in a research project from beginning to end and integrate that unique perspective with classroom lessons and public outreach programs SOFIA s Airborne Astronomy Ambassadors program is a yearly professional development opportunity extended to educators through a competitive peer reviewed process This year s educators are Melvin Gorman and Gordon Serkis Chinle Junior High School in Chinle Arizona Ira Harden and Vincente Washington City Honors College Preparatory Charter School in Inglewood California Clifford Gerstman and Susan Groff Middle College High School in Santa Ana California Mike Cimino Heritage Middle School and John Clark Deltona High School in Deltona Florida Randi Brennon Hawaii Academy of Arts and Sciences in Pahoa Hawaii Jo Dodds Twin Falls Senior High School in Twin Falls Idaho Ralph Peterson North Gem High School in Bancroft Idaho Jennifer Carter and Claudett M Edie Rowan County Senior High School in Morehead Kentucky Chelen Johnson Breck School in Golden Valley Minnesota Matt Oates Dilworth STEM Academy in Sparks Nevada Dan Ruby Fleischmann Planetarium and Science Center in Reno Nevada Ryan Munkwitz and John Walsh Southampton Intermediate and High School in Southampton New York James Johnson Children s Center for Treatment Education in Custer City Pennsylvania Adriana Alvarez and Mariela Aguirre Alicia R Chacon International School in El Paso Texas David V Black Walden School of Liberal Arts in Provo Utah Carolyn Bushman Wendover Jr Sr High School in Wendover Utah Sarah Scoles National Radio Astronomy Observatory and Anne Smith Green Bank Middle School in Green Bank West Virginia Constance Gartner Wisconsin School for the Deaf in Delavan Wisconsin These educators submitted applications describing how they plan to take what they learn from SOFIA back to their classrooms and communities to help

    Original URL path: http://www.lpi.usra.edu/features/sofia/012612/ (2016-02-15)
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  • Vesta Likely Cold and Dark Enough for Ice
    tilted at only about 1 5 As a result of its large tilt Vesta has seasons and every part of the surface is expected to see the Sun at some point during Vesta s year The presence or absence of water ice on Vesta tells scientists something about the tiny world s formation and evolution its history of bombardment by comets and other objects and its interaction with the space environment Because similar processes are common to many other planetary bodies including the Moon Mercury and other asteroids learning more about these processes has fundamental implications for our understanding of the solar system as a whole This kind of water ice is also potentially valuable as a resource for further exploration of the solar system Although temperatures on Vesta fluctuate during the year the model predicts that the average annual temperature near Vesta s north and south poles is less than roughly 200 F 145 K That is the critical average temperature below which water ice is thought to be able to survive in the top 10 feet or so few meters of the soil which is called regolith Near Vesta s equator however the average yearly temperature is roughly 190 F 150 K according to the new results Based on previous modeling that is expected to be high enough to prevent water from remaining within a few meters of the surface This band of relatively warm temperatures extends from the equator to about 27 north and south in latitude On average it s colder at Vesta s poles than near its equator so in that sense they are good places to sustain water ice says Stubbs But they also see sunlight for long periods of time during the summer seasons which isn t so good for sustaining ice So if water ice exists in those regions it may be buried beneath a relatively deep layer of dry regolith The modeling also indicates that relatively small surface features such as craters measuring around 6 miles 10 kilometers in diameter could significantly affect the survival of water ice The bottoms of some craters could be cold enough on average about 100 K for water to be able to survive on the surface for much of the vestan year about 3 6 years on Earth Stubbs explains Although at some point during the summer enough sunlight would shine in to make the water leave the surface and either be lost or perhaps redeposit somewhere else So far Earth based observations suggest that the surface of Vesta is quite dry However the Dawn spacecraft is getting a much closer view Dawn is investigating the role of water in the evolution of planets by studying Vesta and Ceres two bodies in the asteroid belt that are considered remnant protoplanets baby planets whose growth was interrupted when Jupiter formed Dawn is looking for water using the gamma ray and neutron detector GRaND spectrometer which can identify hydrogen rich deposits that could be associated with water

    Original URL path: http://www.lpi.usra.edu/features/vesta/ (2016-02-15)
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  • Kepler Mission Finds Three Smallest Exoplanets
    by continuously monitoring more than 150 000 stars looking for telltale dips in their brightness caused by crossing or transiting planets At least three transits are required to verify a signal as a planet Follow up observations from groundbased telescopes also are needed to confirm the discoveries The latest discovery comes from a team led by astronomers at the California Institute of Technology in Pasadena The team used data publicly released by the Kepler mission along with follow up observations from the Palomar Observatory near San Diego and the W M Keck Observatory atop Mauna Kea in Hawaii Their measurements dramatically revised the sizes of the planets from what was originally estimated revealing their small nature The three planets are very close to their star taking less than two days to orbit around it The KOI 961 star is a red dwarf with a diameter one sixth that of our Sun making it just 70 bigger than Jupiter This is the tiniest solar system found so far said John Johnson the principal investigator of the research from NASA s Exoplanet Science Institute at the California Institute of Technology in Pasadena It s actually more similar to Jupiter and its moons in scale than any other planetary system The discovery is further proof of the diversity of planetary systems in our galaxy Red dwarfs are the most common kind of star in our Milky Way galaxy The discovery of three rocky planets around one red dwarf suggests that the galaxy could be teeming with similar rocky planets These types of systems could be ubiquitous in the universe said Phil Muirhead lead author of the new study from Caltech This is a really exciting time for planet hunters The discovery follows a string of recent milestones for the Kepler mission In December

    Original URL path: http://www.lpi.usra.edu/features/kepler/011912/ (2016-02-15)
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  • Montana Students Pick Winning Names for Moon Craft
    September 2011 The 28 students of Nina DiMauro s class at the Emily Dickinson Elementary School have really hit the nail on the head said Maria Zuber GRAIL principal investigator from the Massachusetts Institute of Technology in Cambridge We were really impressed that the students drew their inspiration by researching GRAIL and its goal of measuring gravity Ebb and Flow truly capture the spirit and excitement of our mission Zuber and Sally Ride America s first woman in space and CEO of Sally Ride Science in San Diego selected the names following the contest which attracted 890 proposals via the Internet and mail The contest invited ideas from students ages 5 18 enrolled in U S schools Although everything from spelling and grammar to creativity was considered Zuber and Ride primarily took into account the quality of submitted essays With submissions from all over the United States and even some from abroad there were a lot of great entries to review Ride said This contest generated a great deal of excitement in classrooms across America and along with it an opportunity to use that excitement to teach science GRAIL is NASA s first planetary mission carrying instruments fully dedicated to education and public outreach Each spacecraft carries a small camera called GRAIL MoonKAM Moon Knowledge Acquired by Middle school students Thousands of students in grades five through eight will select target areas on the lunar surface and send requests for study to the GRAIL MoonKAM Mission Operations Center in San Diego The winning prize for the Dickinson students is to choose the first camera images Dickinson is one of nearly 2000 schools registered for the MoonKAM program which is led by Ride and her team at Sally Ride Science in collaboration with undergraduate students at the University of California in

    Original URL path: http://www.lpi.usra.edu/features/grail/011912/ (2016-02-15)
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  • NASA’s Twin Grail Spacecraft Reunite in Lunar Orbit
    unknown GRAIL B achieved lunar orbit at 2 43 p m PST 5 43 p m EST on January 1 GRAIL A successfully completed its burn on December 31 at 2 00 p m PST 5 00 p m EST The insertion maneuvers placed the spacecraft into a near polar elliptical orbit with an orbital period of approximately 11 5 hours Over the coming weeks the GRAIL team will execute a series of burns with each spacecraft to reduce their orbital period to just under two hours At the start of the science phase in March 2012 the two GRAILs will be in a near polar near circular orbit with an altitude of about 34 miles 55 kilometers During GRAIL s science mission the two spacecraft will transmit radio signals precisely defining the distance between them As they fly over areas of greater and lesser gravity caused by visible features such as mountains and craters and masses hidden beneath the lunar surface the distance between the two spacecraft will change slightly Scientists will translate this information into a high resolution map of the Moon s gravitational field The data will allow scientists to understand what goes on below the lunar surface This information will increase knowledge of how Earth and its rocky neighbors in the inner solar system developed into the diverse worlds we see today Each spacecraft carries a small camera called GRAIL MoonKAM Moon Knowledge Acquired by Middle school students with the sole purpose of education and public outreach The MoonKAM program is led by Sally Ride America s first woman in space and her team at Sally Ride Science in collaboration with undergraduate students at the University of California in San Diego GRAIL MoonKAM will engage middle schools across the country in the GRAIL mission and lunar

    Original URL path: http://www.lpi.usra.edu/features/grail/010412/ (2016-02-15)
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  • New Star Cluster W3A Images Captured by SOFIA Observatory
    stars in the cloud have on their smaller siblings and on the cycle of star birth The SOFIA observations reveal the presence of some 15 massive stars in various stages of their birth process Toward the left of the inset image a small bubble arrow has been cleared out of the gas and dust by the most massive star in this cluster This bubble is surrounded by a dense shell green of material in which some of the dust and all of the large molecules have been destroyed That shell is surrounded by mostly untouched cloud material traced by the red emission from cooler dust Astronomers have evidence that the expansion of such bubbles around massive newly born stars acts to compress nearby material and trigger the condensation of more stars Most stars in the Milky Way including our Sun are thought to have formed in such violent environments The processes involved are difficult to follow because light produced by these hot stars at visual and ultraviolet wavelengths can t escape the surrounding clouds of interstellar material Short wavelength starlight absorbed by small dust grains and large molecules sets these clouds aglow at the longer infrared wavelengths observed by SOFIA allowing astronomers to peer inside the clouds and study the internal structures and processes The SOFIA observations were made using the FORCAST instrument Faint Object Infrared Camera for the SOFIA Telescope Principal Investigator Terry Herter Cornell University The data were analyzed and interpreted by the FORCAST team with Francisco Salgado and Alexander Tielens of the Leiden Netherlands Observatory plus SOFIA staff scientist James De Buizer These data are subjects of papers submitted for publication in The Astrophysical Journal The FORCAST camera combined with SOFIA s large telescope allows the W3 region s star formation to be probed at mid infrared

    Original URL path: http://www.lpi.usra.edu/features/sofia/011912/ (2016-02-15)
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  • LPI to Host First FameLab Astrobiology Competition
    without the use of PowerPoint The competitors will focus on astrobiology the study of our origins and the search for life elsewhere in the universe We invite you to cheer on these brave young scientists as they make science story magic of three minutes and one fascinating topic Bring your burning questions about life in the universe and ask an astrobiologist over coffee and dessert after the event Tim Merriman

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