December 8, 2011
image by Philippe Tosi, Pic du Midi, France
Mare Crisium is one of the most identifiable places on the Moon. It is big and by itself, not connected to other maria. It has little of observational interest on its floor beyond Lick and Yerkes on the shallow bench that hugs the western rim. But all around Crisum are fascinating craters, starting with bright-walled Proclus right in front. With this illumination only one of it avoidance zone-defining rays is visible, plus a few fainter rays deposited on Mare Crisium. Proclus is a very young, but undated, oblique impact crater. At the left edge of Philippe's image is a fascinating crater with severe challenges for observers and imagers. Tiny dark halo craters and narrow rilles are on the floor but are visible only in the best images. The best chance to see the DHC is probably at full Moon when the halos are more conspicuous. One of my favorite craters is at the extreme right. Taruntius is a floor-fractured crater whose elevated floor is wreathed with concentric fractures. As this high Sun view shows a quarter of the floor is draped with dark material, probably ash that erupted from the magma that uplift the floor.
C.14 F/11 + 742 nm IR filter + skynyx 2.1 M camera; processed by Registax 6 (350images) and Photomatix 4 pro developped by HDRsoft.
Rükl plate 26
Yesterday's LPOD: Non-Concentric Basin Scarp
Tomorrow's LPOD: Noticing What is Missing