spacetoday.net: Lunar mascons linked to impacts

Posted: Sun, Jun 2, 2013, 8:40 AM ET (1240 GMT)
GRAIL illustration (NASA)

Scientists have associated irregularities in the Moon's gravity field with impacts by asteroids and comets early in the Moon's history. In a paper in the journal Science, scientists used the detailed gravity map of the Moon created by NASA's GRAIL mission last year to study the origin of mass concentrations, or mascons, below the lunar surface that create localized variations of the lunar gravity field. Using models of large impacts, scientists believe the mascons formed after impacts by asteroids and comets early in the Moon's history, when its interior was much hotter than now. Those models showed the mixing of light crust material and denser mantle material in the impacts created the mascons, which crate bullseye-like patterns in the lunar gravity map.