The ten most promising mission concepts of the 43 proposed to NASA for possible launch to Mars in 2007 as part of the “Scout” program were selected last week to receive funding for six months of continued studies. Included in the ten concepts selected for study are missions to return samples of Martian atmospheric dust and gas, networks of small landers, orbiting constellations of small craft, and a rover that would attempt to establish absolute surface ages of rocks and soils. NASA plans to evaluate the ten innovative concepts using rapid six- month studies as a means for jump-starting the identification of new Mars Scout missions that will compete for a possible launch in 2007. The proposals were submitted to NASA’s Mars Exploration Program in the Office of Space Science in Washington, DC, in response to a call for proposals in March 2001. Those selected will receive up to $150,000 each for the study.