Science reporter Mark Washburn's Mars odyssey begins leisurely enough with historical accounts of Schiaparelli's famous ""canali"" blown up into intelligent Martian canals by Percival Lowell. Droll chapters follow on the appeal of the red planet to the likes of Edgar Rice Burroughs, H. G. Wells, Ray Bradbury, or Robert Heinlein. The pace picks up next with a you-are-there story of life at Jet Propulsion Laboratory in Pasadena a little over a year ago during the Viking Orbiter and Lander events. Washburn's savvy knowledge of engineering and science puts the billion-dollar-plus project in the proper perspective of awesome engineering and ingenious science. It is hard not to be moved again by the successful landing on Mars, by the frustrating ""glitches"" and long-range fixes; it is hard not to be disappointed and still hopeful at the equivocal findings of the biology experiments. Acknowledging that scientists may yet learn more about life on Mars through earth simulation, Washburn eloquently demonstrates how much (else) we have learned about Mars past and present. His last pages on future space projects using the space shuttle, solar sails, mobile Rovers on planetary sites--with some Sagan-inspired artificial intelligence to run things--make it clear that space exploration is a Good Thing. Not only does it add to human knowledge in an exciting and dramatic fashion, it may also blunt the effort to put all our brains and dollars into defense.