Word: vegas
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Dates: during 1980-1989
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...flight by three cosmonauts aboard the Salyut 7 space station, a daring repair mission to restart that station after a near total power failure, and a highly sophisticated radar mapping of Venus by two robot Venera probes. Earlier this month the Soviets dazzled the international scientific community with their Vega 1 and Vega 2 inspections of Halley's comet. Each Vega flyby was preceded by a swing past Venus to drop an instrument-laden balloon into the planet's dense atmosphere...
...Vega 1's camerawork was a triumph of technology. While whipping by Halley's at a speed of 175,000 m.p.h. (relative to the comet), the spacecraft's TV cameras shot some 500 pictures in about three hours. Transmitted across 109 million miles of space, each picture took nine minutes to arrive in Moscow, where it was colored by computer to emphasize differences in brightness. The first images showed only the coma, the great cloud of gas and dust surrounding the nucleus, as a fuzzy, violet-fringed, blue-green ball with a yellow center. But in images that Vega...
Early evaluation of data from Vega 1 showed that the craft encountered less dust than expected as it approached the comet. But Physicist John Simpson of the University of Chicago, who designed the only American instrument -- a dust detector -- aboard Vega, noted that as the spacecraft departed, it passed through a "huge spike of dust" with particles about the size of those in cigarette smoke. Simpson and other scientists interpreted the spike as a burst of dust and gas erupting from the surface of the nucleus. Other Vega instruments seemed to show that the icy cometary surface was being evaporated...
...Vega 1 also served as a pathfinder for two other craft in the Halley's flotilla. By helping scientists determine the comet's precise path, it enabled them to make accurate last-minute corrections in the courses of Vega 2 and Giotto. The second Vega was to pass within 5,000 miles of the comet on March 9, supplementing Vega 1's findings. Giotto's mission four days later was to swoop to about 300 miles of the nucleus, shooting close-up pictures as it passed. Precision pathfinding was less important for the Japanese craft. Suisei, designed to study...
...week's end scientists were worried about Giotto's chances. As they continued to interpret Vega 1's data, they discovered that its passage through the dust jet had damaged 45% of the craft's solar panels. During Giotto's much closer encounter with the comet, the European probe was bound to pass through far thicker clouds of dust on what some scientists characterized as a "kamikaze mission...