Radar Strip Showing Crater Bessel

Mini-RF S-band zoom synthetic aperture radar (SAR) image strip through central Mare Serenitatis on the near side of the Moon (approximate longitude of strip ~ 18° E; center latitude ~ 20° N). The radar strip runs through the crater Bessel (inset; 15 km (9 mile) diameter; center at 21.8° N, 17.9° E) and covers the highlands of the Haemus Mts. (rim of Serenitatis basin) in its southern (bottom) third. The full-resolution SAR data are 30 m (90 feet). The streaks of bright and dark material in the walls of Bessel probably reflect the blockiness of landslides within the crater, brighter streaks having more blocks of the 10-cm (4-inch) scale. The radar strip covers a major geological boundary in Mare Serenitatis; the darker, lower maria has higher titanium content than central Serenitatis. We see this geological boundary in the Mini-RF radar image, caused by higher absorption of RF energy by the high content of the iron-titanium oxide mineral ilmenite. Thus, Mini-RF SAR images can be used to map the titanium content of the lunar maria. The background image is part of the Clementine global mosaic.