November 20, 2007

Jump to: navigation, search

Limb Gift

Petavius on Limb.jpg
Apollo 15 M2525 image from LPI Apollo Image Atlas

Looking due south, an Apollo 15 crewman (Al Worden?) clicked away with his Hasselblad camera as the ship came around the eastern limb of the Moon. For completeness, the crater in the foreground - Holden - must be identified, but what is really fascinating is the large crater near the limb. Orbiting spacecraft give us such unexpected views that it is delight to realize that the big crater is familiar Petavius, with its huge rille seen to be a complete dropoff, with no raised lip to give warning. The central mountain is massive, about 30 km wide at is base, with many lower peaks leading toward the summit. The two large dark spots - pyroclastics and maybe mare lava - are visible near the floor’s edge, and beautiful stair-step terraces climb the wall near where the rille touches it. Visual observing when the Sun sets over Petavius suggests that the inner half of the floor is higher that the edges, and that is confirmed by the bowing upward of the rille as it approaches the central peaks. Once you are satiated with this wonderful view, scroll to the far right for an over the rim peek at Wrottesley, and on to another perspective of a recent LPOD.

Chuck Wood

Related Links:
Rükl plates 59 & 60

Yesterday's LPOD: The Case of the Missing Peak

Tomorrow's LPOD: Uninspiring, but an Active History


Register, Log in, and join in the comments.