Word: perihelion
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...national medal, with no monetary reward-how quaint. The nationals have always had pride of place, the only event in the sport to be regularly televised and, for an American skater, the imprimatur of success. Yes, there is a world championship, and every four years the perihelion of the Olympics. But to be national champ has meant being at the top of the game...
...warhead-tipped rocket to intercept it and explode, nudging it into a new orbit that would carry it safely past Earth. For a small asteroid detected years and many orbits before its destined collision, the solution would be straightforward. "You apply some modest impulse to it at its perihelion, or closest point to the sun, using conventional explosives," explains Gregory Canavan, a senior scientist at Los Alamos National Laboratory. "The slight deflection that results will amplify during each orbit, ensuring that the asteroid misses Earth by a wide margin...
Meteorologists attributed the abnormally high tides to an unusual cosmic dance. The combination of factors included syzygy (pronounced syz-uhjee), a twice-monthly condition in which the earth, sun and moon are most closely in alignment; perigee, when the moon is closest to the earth in its monthly orbit; perihelion, when the earth is at its shortest distance from the sun; and the tidal bulge caused by the moon when it reaches the southernmost point in its orbit...
...from view, not to be visible from earth again until after it emerged from the sun's glare in mid-February. Unfortunately for earthbound observers, it was during that unseen passage that Halley's put on its most dramatic display so far. As the comet neared its Feb. 9 perihelion, its closest approach to the sun (about 55 million miles), the searing solar rays caused increasing amounts of material to evaporate from its icy surface. Eventually the comet's enveloping gas cloud, or coma, grew to more than 12.5 million miles across, temporarily becoming the largest object in the solar...
...data used to create the image had arrived in California by an unusual route. Looking for ways to view Halley's comet at perihelion, Ames scientists had hit upon the idea of using the Pioneer 12 spacecraft, which has been orbiting Venus since December 1978, surveying the planet with an array of instruments. Around the time of Halley's perihelion, they realized, Venus--and thus Pioneer--would be in position to have a direct view of the comet. Late in December the scientists ordered the spacecraft to pivot 90 degrees and point its ultraviolet scanner at the comet...