The Lunar and Planetary Science Conference announced on 2015-03-16 that a 198 km wide crater has been found on the moon using the GRAIL spacecraft that uses gravitational field mapping. This enabled the discovery of craters below the surface. It's been named the Earhart crater. Nice gravitational photos can be found in the links.
(Score: 1) by KiloByte on Saturday March 21 2015, @12:29AM
The word "massive" doesn't imply "mass", they merely share etymology. In fact, out of four definitions given by WordNet, only one speaks of mass at all -- the other ones being "imposing in size/bulk", "solid", "imposing in scale/scope/degree/power". The crater isn't solid either, but two other definitions apply to it just fine.
Ceterum censeo systemd esse delendam.