Written by Guy Webster
Pasadena, CA – Scientists using images from NASA’s Mars Reconnaissance Orbiter have estimated that the planet is bombarded by more than 200 small asteroids or bits of comets per year forming craters at least 12.8 feet (3.9 meters) across.
Researchers have identified 248 new impact sites on parts of the Martian surface in the past decade, using images from the spacecraft to determine when the craters appeared. The 200-per-year planetwide estimate is a calculation based on the number found in a systematic survey of a portion of the planet.
Written by Nancy Neal-Jones / Bill Steigerwald
Greenbelt, MD – Electrically charged lunar dust near shadowed craters can get lofted above the surface and jump over the shadowed region, bouncing back and forth between sunlit areas on opposite sides, according to new calculations by NASA scientists.
The research is being led by Michael Collier at NASA’s Goddard Space Flight Center, Greenbelt, MD, as part of the Dynamic Response of the Environment At the Moon (DREAM) team in partnership with the NASA Lunar Science Institute (NLSI), managed at NASA’s Ames Research Center, Moffett Field, CA.
Written by Jia-Rui Cook
Pasadena, CA – Titan’s siblings must be jealous. While most of Saturn’s moons display their ancient faces pockmarked by thousands of craters, Titan – Saturn’s largest moon – may look much younger than it really is because its craters are getting erased.
Dunes of exotic, hydrocarbon sand are slowly but steadily filling in its craters, according to new research using observations from NASA’s Cassini spacecraft.
Written by Dr. Tony Phillips
Washington, D.C. – Just when you thought Christmas was over: At the end of the day on December 25th, a pair of holiday lights will pop out of the deepening twilight. Jupiter and the Moon are having a Christmas conjunction.
It’s a beautiful apparition, visible all around the globe. Even city dwellers, who often miss astronomical events because of light pollution, can see the show. Separated by less than 2 degrees, the bright pair will beam right through urban lights.
Written by D.C. Agle
Pasadena, CA – NASA has named the site where twin agency spacecraft impacted the moon Monday in honor of the late astronaut Sally K. Ride, who was America’s first woman in space and a member of the probes’ mission team.
Last Friday, Ebb and Flow, the two spacecraft comprising NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission, were commanded to descend into a lower orbit that would result in an impact Monday on a mountain near the moon’s north pole.
Written by Jia-Rui C. Cook and D.C. Agle
Pasadena, CA – In a preliminary analysis of images from NASA’s Dawn mission, scientists have spotted intriguing gullies that sculpt the walls of geologically young craters on the giant asteroid Vesta.
Led by Jennifer Scully, a Dawn team member at the University of California, Los Angeles, these scientists have found narrow channels of two types in images from Dawn’s framing camera – some that look like straight chutes and others that carve more sinuous trails and end in lobe-shaped deposits. The mystery, however, is what is creating them?
Written by Dr. Tony Phillips
Washington, D.C. – Observations by NASA’s MESSENGER spacecraft provide compelling support for the long-held hypothesis that Mercury harbors abundant water ice and other frozen materials in permanently shadowed polar craters.
“The new data indicate the water ice in Mercury’s polar regions, if spread over an area the size of Washington, D.C., would be more than 2 miles thick,” said David Lawrence, a MESSENGER participating scientist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, MD, and lead author of one of three papers describing the findings in the online edition of Science Express.
Written by Priscilla Vega and Jia-Rui Cook
Pasadena, CA – A new video from NASA’s Dawn mission reveals the dappled, variegated surface of the giant asteroid Vesta.The animation drapes high-resolution false color images over a 3-D model of the Vesta terrain constructed from Dawn’s observations.
This visualization enables a detailed view of the variation in the material properties of Vesta in the context of its topography.
NASA’s Mars Science Laboratory mission to land near Mount Sharp to link Mars Geology’s Past and Future
Written by D.C. Agle
Pasadena, CA – One particular mountain on Mars, bigger than Colorado’s grandest, has been beckoning would-be explorers since it was first sighted from orbit in the 1970s. Scientists have ideas about how it took shape in the middle of ancient Gale Crater and hopes for what evidence it could yield about whether conditions on Mars have favored life.
No mission to Mars dared approach it, though, until NASA’s Mars Science Laboratory mission, which this August will attempt to place its one-ton rover, Curiosity, at the foot of the mountain. The moat of flatter ground between the mountain and the crater rim encircling it makes too small a touchdown target to have been considered safe without precision-landing innovations used by this mission.
Written by Jia-Rui C. Cook
Pasadena, CA – NASA’s Cassini spacecraft has “sniffed” molecular oxygen ions around Saturn’s icy moon Dione for the first time, confirming the presence of a very tenuous atmosphere.
The oxygen ions are quite sparse – one for every 0.67 cubic inches of space (one for every 11 cubic centimeters of space) or about 2,550 per cubic foot (90,000 per cubic meter) – show that Dione has an extremely thin neutral atmosphere.
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