Large impacts on the Moon can form wide craters and turn surface rock liquid. Geophysicists once assumed that liquid rock would be homogenous when it cooled. Now researchers have found evidence that pre-existing mineralogy can survive impact melt. Pre-existing mineral deposits on the Moon (sinuous melt, above) survived impacts powerful enough to melt [continue reading]
Large impacts of asteroids may have transferred carbonaceous material to the protoplanet and inner Solar System The protoplanet Vesta has been witness to an eventful past: images taken by the framing camera onboard NASA’s space probe Dawn show two enormous craters in the southern hemisphere. The images were obtained during Dawn’s year-long visit [continue reading]
New study traces Moon evaporation and leads to questions about why Earth has so much water Fresh examinations of lunar rocks gathered by Apollo mission astronauts have yielded new insights about the Moon’s chemical makeup as well as clues about the giant impacts that may have shaped the early beginnings of Earth and [continue reading]
Among the oddities of the outer Solar System are the middle-sized moons of Saturn, a half-dozen icy bodies dwarfed by Saturn’s massive moon Titan. According to a new model for the origin of the Saturn system, these middle-sized moons were spawned during giant impacts in which several major satellites merged to form Titan. Saturn’s [continue reading]
Using the planetary radar system at Arecibo Observatory, astronomers have determined that asteroid 2012 LZ1 is twice as large as originally estimated based on its brightness, and large enough to have serious global consequences if it were to hit the Earth. However, a new orbit solution also derived from the radar measurements shows that [continue reading]
Researchers anticipate that asteroid 2011 AG5, discovered in January 2011, will fly safely past and not impact Earth in 2040. Current findings and analysis data were reported at a recent workshop at NASA’s Goddard Space Flight Center in Greenbelt, Md., attended by scientists and engineers from around the world. Discussions focused on observations of potentially [continue reading]