January 8, 2018
The Youngest Large Crater On the Moon?
Originally published July 13, 2008
Giordano Bruno image from JAXA/Kaguya Image Gallery
Recently a 15 m wide impact crater formed in Peru, and the one-km wide Meteor Crater resulted from an impact in northern Arizona about 50,000 years ago. About a million years earlier the 10 km diameter Bosumtwi impact crater was blasted out the the West African jungle. Craters happen, but did a 22 km crater form on the Moon 900 years ago? Most lunar scientists are doubtful, but it could have. The possibly very young crater is Giordano Bruno, 12 degrees around the Moon's northeastern limb. The evidence for its extraordinarily youthful formation is the direct observation by English monks, the problem is the interpretation of their report. In 1978 Jack Hartung reported that on June 18, 1178 five monks saw a bright flash on the edge of the Moon closest to Bruno's position. Hartung proposed that the monks witnessed the impact of the the young, ray-strewing crater. Scientists studying data from the Apollo seismometers liked that theory for they had discovered that the Moon was ringing, presumably caused by a major impact in the last 1000 years. But models of such impacts on the Moon imply that a magnificent meteor shower would occur on Earth soon afterward as the crater's high speed ejecta reached Earth - none was reported. Who are you going to believe, computer modelers or pious monks?
Taken by the HDTV camera May 9, 2008.
Clementine Atlas plate 29
Yesterday's LPOD: No More Crater
Tomorrow's LPOD: Sheet 8