Lunar Serendipity

Mini-SAR nears completion of its first mapping cycle, Paul Spudis, Air&Space
“A particularly interesting and unusual feature was imaged by Mini-SAR almost by accident. Because of a timing error, we started a few mapping passes of the south pole early, before the scheduled start at 80 degrees south latitude. Good thing we did! We covered the fresh, spectacular Schroedinger impact basin, on the lunar far side. Schroedinger shows an unusual, keyhole-shaped crater along a long fissure on the basin floor. This crater is surrounded by optically dark material, which has been interpreted as volcanic ash deposits. The new Mini-SAR image shows that this material is also dark in radar reflectivity, exactly what would be expected from a fine-grained, block-free deposit. Thus, our radar images confirm the geological interpretation first derived in 1994 from Clementine images.”