May 23, 2013
Another Go At Scheiner
top image by Jose Cabello and bottom from LRO QuickMap
When looking at Jose's new mosaic of the south polar region I noticed the odd curved ridge (arrow) on the south side of Scheiner's floor. This looked familiar and checking the Moon Wiki entry for Scheiner I found that I had discovered the ridge at least twice earlier! First, was in 2007 and the second time was just a year ago. Both times I sought unsuccessfully for a reasonable interpretation. And since there were no comments for either LPOD, nobody else must have had a good idea. But now I have a suggestion that is good enough to close the file on Scheiner's mysterious ridge. If you look closely at the LRO image you will notice a smaller parallel ridge closer to the center of the floor, and squashed by the fresh crater Scheiner A. I propose that these two ridges are the sides of a basin secondary crater chain with about 6 craters. As I wrote in an earlier LPOD (with a different interpretation) these craters seem to have been partially covered by the smooth material on Scheiner's floor; probably ejecta from the Orientale basin. The only minor weakness to this new interpretation is that the putative chain doesn't seem to be radial to any basin.
13/05/22 20:54UTC. C11, dmk21au618 e IR-Pass685nm.
Rükl plate 72
21st Century Atlas chart 15.
Yesterday's LPOD: Layers of "B"
Tomorrow's LPOD: A Modest Proposal