March 7, 2013
Small Feature Tour
image by Jocelyn Serot, France
How many interesting features do you see here? Let's accept and pass over all the impact craters from 40 km wide Lansberg (the same size as the similar but much younger Aristarchus), the 64 km wide half-rimmed crater Euclides P near the middle of the image, to the RIphaeus Mountains arc, a remnant of a 210 km wide ancient crater. Here are some features that Jocelyn pointed out. Notice the mini-Straight Wall south of Lansberg. This 34 km long fault rises 60-70 m higher on the east side than the west. I don't know why this little fault is here (there is a similar one south of Aristarchus too), but it is about radial to the center of the Imbrium Basin so we can wave our hands and say it must be related somehow. Further west is a cluster of three known swell-like domes. The mare ridge below the domes qualifies as being interesting. Jocelyn notes that it is radial to Mare Insularum, and I like that it has a ghostly look, which is just due to it sticking up a little into the sunlight. Finally, note the 12 km long trough at the north end of the Riphaeus arc. LRO QuickMap reveals this is to be a broad-floored rille, the question is what is this rille doing sandwiched between a mountain chain and an isolated mountain.
Rükl plate 42
21st Century Atlas chart 22.
Yesterday's LPOD: Homeward Bound
Tomorrow's LPOD: 50 Year Uncertainty