image: This is a schematic showing the stream of charged hydrogen ions carried from the Sun by the solar wind. One possible scenario to explain hydration of the lunar surface is that during the daytime, when the Moon is exposed to the solar wind, hydrogen ions liberate oxygen from lunar minerals to form OH and H2O, which are then weakly held to the surface. At high temperatures (red-yellow) more molecules are released than adsorbed. When the temperature decreases (green-blue) OH and H2O accumulate. This image relates to an article that appeared in the Sept. 24, 2009, issue of Science Express, published by AAAS. The study, by Dr. Jessica M. Sunshine at University of Maryland in College Park and colleagues, was titled, "Temporal and Spatial Variability of Lunar Hydration as Observed by the Deep Impact Spacecraft." view more
Credit: [Image courtesy of University of Maryland/F. Merlin/McREL]