Today's Featured Image highlights the wall of Jansen U crater, located at the northeast section of Mare Tranquillitatis. Jansen U is a 3.28 km diameter crater with a teardrop shaped cavity, and likely originated from a low angled oblique impact (see next NAC context image). The high reflectance area includes many boulders is the crater wall. The low reflectance area in the lower right of the image, which includes a smaller crater (~130 m in diameter), is the rim and shallowly sloping ejecta blanket. The upper left corner of the image, which is covered by low reflectance materials (but not as low as the background surface), corresponds to the crater floor.
Jansen U crater has an eye-catching appearance due its ovoid shape and brilliant contrast between the low reflectance floor higher reflectance crater walls. Since no indication of impact melt is seen on the crater floor (e.g. fractures or viscous flow features), the floor is likely covered by post impact in-filling materials. Little by little space weathering produces the mature regolith everywhere on the surface, while the slope failure slumps mature material away continuously. These mass wasting and weathering processes often result in striking albedo patterns.
Explore Jansen U crater, contrasting reflectance patterns of the wall and the floor in full NAC frame!
Related posts:
Downhill Creep or Flow?, Leathery vs smooth surface, Slope failure near Aratus crater, Crater Covered With Boulders!, Bright ridge near Mons Hansteen, Multiple Flow Lobes
Published by Hiroyuki Sato on 11 June 2013