Here, Burrows (Deep Black: Space Espionage and National Security, 1986) offers up a more-or-less definitive history of America's unmanned space exploration from Viking to Galileo--ponderous on occasion, but refreshingly objective and thorough. "In the most honest of all possible worlds there would be two monuments. . .at the Kennedy Space Center. One would be dedicated to the Soviet space program; the other to the news media of the United States. A common tablet might read: 'Without whose presence this establishment might not exist.'" Burrows's tale of the virtual sacrifice of many of the Jet Propulsion Laboratory's valuable deep-space exploration projects for the sake of NASA's flashier manned Apollo project, the Shuttle, and Reagan's SDI program is by now a well-established 20th-century set-piece. The JPL's unmanned projects benefited initially from NASA's enormous budget increases--which were motivated by the USSR's frightening advancements in space and the media's unbounded enthusiasm for astronauts--but time-consuming unmanned space probes soon lost in the p.r. competition to the more instantly gratifying manned missions. The results: the sexy, headline-grabbing Shuttle gobbled up a lion's share of NASA's budget, though it proved undependable and financially disastrous, while the JPL's homely, oft-ignored Viking, Voyager, Magellan, and Galileo probes sent back enough data to keep scientists busy for decades. In the Nineties, a more sober NASA is attempting to better integrate scientific considerations in its future plans. Whether the nation's will to explore can survive the inevitable failures and dull stretches remains to be seen. Former JPL Director Bruce Murray's Journey Into Space (1989) gives a more personal, passionate history of the lab's involvement with NASA, but lacks this book's big picture and its update.