January 20, 2011
A Basin or Just a Big Crater?
image by Павел Пресняков (Pavel Presnyakov), Kiev Ukraine
Have you ever observed Bailly? Its a big crater just on the western limb. It isn't very deep (maybe; there isn't a reliable modern measurement) for its original floor appears to be at least partially filled in, presumably with Orientale's ejecta. There is no evidence of a central peak, but it might not be unusual because at about 290 km diameter, Bailly is big enough to be a two-ring basin. Bill Hartmann and I thought it was 40 years ago, and Pavel's great image and the new overhead view provided by the LRO-WAC global mosaic continues to provide hints of the putative inner ring. The mosaic image shows very well an Orientale crater chain crossing the far floor of Bailly, and a ridge associated with the chain is nicely visible in Pavel's image, as is a linear crater chain on the crater rim. While the terminator is near the western limb take a look for an inner ring.
11-11-08, 16:33 UT. 350 mm newtonian + barlow 5x Vac-135, b/w 1280x1024 500 in Registax 6 alpha
Rükl plate 71
Pavel's new website
Yesterday's LPOD: Solstice Red, Sort Of
Tomorrow's LPOD: A Question of Paternity