Among the ringed gas giant planet Saturn's amazing collection of 62 diverse, bizarre, and beautiful moons and moonlets, sometimes one of them just seems to stand out in the crowd. Such a moon is little Methone. Looking like a shiny white egg in Space, and composed of very lightweight fluffy stuff, Methone is less dense than any other known moon or asteroid in our Solar System. In March 2013, astronomers announced at the 44th Lunar and Planetary Science Conference held in the Woodlands, Texas, that this strange little 5-kilometer-size moon is one of a batch of Space eggs in orbit around Saturn!
Tracing our Moon's changing porosity may ultimately help astronomers to track the trajectory of the invading army of a multitude of lunar impactors, that occurred during the Late Heavy Bombardment, 4 billion years ago.
Dr. Soderblom calculated the gravity signatures both in and around 1,200 craters that had been excavated by impacting objects on the lunar far side. He then went on to compare the gravity within each crater with the gravity of the surrounding terrain. Dr. Soderblom did this in order to determine whether an impact increased or decreased the local porosity.