Word: nasa
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Dates: during 1980-1989
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...NASA used similar generators on 22 space missions, but no one paid much attention until the Challenger tragedy dramatized the risks of space launches. The space agency admits that there have been three accidents involving RTG- powered vehicles. The most significant was in 1964, when a satellite launched by the Air Force burned up over the Pacific, tripling the amount of radioactive plutonium 238 in the environment. It is not clear what health effects that might have had. The generators were then redesigned, and in two subsequent accidents in which spacecraft broke apart, no radioactivity is known to have escaped...
...NASA has gone to extraordinary lengths to make sure the RTGs are safe. Each of the 144 plutonium pellets in the generators, designed by General Electric, is surrounded by an iridium shell. Coated pellets are then encased by two graphite shells and finally by an aluminum shroud. The U.S. Department of Energy has spent $50 million testing the generators. In one experiment, engineers fired shrapnel traveling 700 ft. per sec. at the iridium casings. None was pierced. In another test, scientists tacked an RTG to a solid rocket booster and blew it up. No damaged graphite shells were detected...
Space officials calculate that the chances of plutonium being released in an aborted mission are no greater than 1 in 1,428. Declares Dudley McConnell, nuclear safety manager for NASA: "You have a thousand times greater chance of dying on the ground from debris falling from an airplane crash than you do from the Galileo mission." Critics, though, remain unconvinced by such assurances. For them, the only real comfort will come when Galileo is gone from earth...
...totally out of the fuzzy picture yet. A small firm in Irvine, Calif., Togai InfraLogic, has already achieved several of the goals MITI set for itself, including a fuzzy computer chip that can perform 28,600 fuzzy-logical inferences per sec. (FLIPS). And NASA is experimenting with fuzzy controllers that could help astronauts pilot the shuttle in earth orbit. The results so far, say NASA officials, are encouraging, and there is growing interest at such aerospace firms as Rockwell and Boeing. "The only barrier remaining" to wider use of fuzzy logic, says Kosko, "is the philosophical resistance of the West...
...November virus infected 6000 computers around the nation and hit systems at the National Aeronautics and Space Administration (NASA) and the U.S. Air Force Logistics Command, among others. Friends have said that Morris meant the virus to be a harmless prank but that it spiraled beyond his control...