image: These concavity index maps are overlaid on digitized Lunar Orbiter IV images. High values of the index (red) indicate increasingly silicic compositions. (A) Aristarchus Crater. (B) Gruithuisen Domes. (C) HansteenAlpha. (D) Lassell. (E) Helmet and Southern Montes Ripheus. This image relates to an article that appeared in the Sept. 17, 2010, issue of Science, published by AAAS. The study, by Dr. Timothy Glotch of Stony Brook University in Stony Brook, N.Y., and colleagues was titled, "Highly Silicic Compositions on the Moon." view more
Credit: Image courtesy of <i>Science</i>/AAAS