Breathtaking” new maps of likely sites of water on Mars showcase their association with geologic features such as Vallis Marineris, the largest canyon in the solar system. The maps detail the distribution of water-equivalent hydrogen as revealed by Los Alamos National Laboratory-developed instruments aboard NASA’s Mars Odyssey spacecraft. In an upcoming talk at the Sixth International Conference on Mars at the California Institute of Technology, in Pasadena, Los Alamos space scientist Bill Feldman and coworkers will offer current estimates of the total amount of water stored near the Martian surface. His presentation will be at 1:20 p.m., Friday, July 25.