Word: comas
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...Wasserman and Edward Bowell have calculated 40 points on the comet's route at which it will pass directly in front of a relatively bright star. During one of these passages, which are expected to last about 15 minutes, they hope to learn how dust is distributed in the coma by analyzing the starlight shining through it. At Mauna Kea Observatory in Hawaii, nearly 14,000 ft. above sea level, Astronomer Dale Cruikshank is using infrared photometry and imagery to measure the heat radiation from Halley's coma and the distribution of dust within it, as well as to look...
...with rocky fragments, dust particles and trace elements. As one of these snowballs swoops toward the sun, said Whipple, solar radiation begins to vaporize ice and frozen gases on the comet's sunward surface by a process called sublimation. The gases, carrying dust with them, form a light-reflecting coma that makes the comet visible from earth...
Many other aspects of cometary theory have since been refined or expanded. By studying the spectra of light emitted from molecules broken down in the gaseous coma, scientists have estimated that a comet's nucleus consists of two-thirds water, one-fifth dust (particles averaging one-thousandth the width of a pinhead) and the rest a mixture of methane, ammonia, carbon dioxide and trace elements...
When a comet is still as far away as 5 AU from the sun, about the distance of Jupiter, its most volatile material begins forming a coma that reflects light. By the time the most powerful telescopes first catch a glimpse of a comet, the coma already obscures the nucleus beneath. For every revolution a typical comet makes around the sun, its diameter is estimated to shrink about 6 ft. Hence the original size of the comet, the length of its orbit and how close it gets to the sun will determine its life-span. Astronomers estimate that Halley...
...millionaire father, which would allow him to quit the force. As usual, ex-Policeman Joseph Wambaugh keeps the uniforms blue and the humor black. Blackpool has also lost a son, and the key witness is another graying officer, Harry Bright, who now lies in an apparently irreversible coma. Also hampering the investigation are a midget who hopes for intimate contact with large ladies, and a Palm Springs houseboy who scouts gay bars for murder suspects in his best butch outfit. Without a program, the bad guys are hard to separate from the good guys, and Blackpool...