Image derived from the Clementine global color data (in 750-nanometer and 950-nanometer wavelengths) showing the concentration of iron in the soils of the lunar surface. Note the high iron levels of nearside maria and elevated iron associated with the South Pole-Aitken Basin on the farside (see topography on slide #19). The very low iron of the central farside suggests a large amount of nearly pure anorthosite, indicating that the early Moon melted globally. See Lucey et al. (1995) for details on this method of iron mapping.
Image processing by ACT Corporation, Alexandria, Virginia; Lunar and Planetary Institute, Houston, Texas; and University of Hawai’i, Honolulu, Hawai’i.