WASHINGTON, Oct. 19 - The Hubble Space Telescope, which normally surveys the edges of the universe, has turned its attention to our nearby Moon and found mineral concentrations that might prove to be sources of oxygen for human visitors, researchers said Wednesday. In an unusual use of the Hubble, astronomers trained the large Earth-orbiting telescope on the Moon in August to take the first high-resolution ultraviolet images of certain geologically interesting areas. The images allow scientists to see areas of mineral variation within the crust and could help identify the most valuable sites for sending robotic and human missions. "This...