Word: coronae
(lookup in dictionary)
(lookup stats)
Dates: during 1940-1949
Sort By: most recent first
(reverse)
Meeting at Harvard Observatory, a small group of leading U.S. astronomers agreed last week that a Swedish physicist, Bengt Edlen, had just thrown a good deal of light on the sun. It concerned the nature of the sun's corona-its turbulent halo of incandescent gases...
...half-million miles into space, sink back and leap again. Sometimes, strangely, clouds of gases appear out of nowhere far above the sun and blazing streamers lick back toward the sun's surface like prankish backward-movies of a high diver. What elements, astronomers have puzzled, form the corona? Where do the backward-flowing flames come from...
...corona is bright, but the sun itself outdazzles it except when blacked out by the moon (or by synthetic eclipses created by the device called a coronagraph). Since each of the 92 standard elements, when hot, glows with distinctive spectrum colors, astronomers can analyze the corona's chemical content with spectroscopes during eclipses. They have found in it about two dozen unidentifiable spectrum bands...
...Physicist Edlen demonstrated that the corona probably consists mostly of heavier elements like iron, calcium, nickel. This was a big surprise to astronomers. Surprise No. 2 was Edlen's calculation that this high excitation which causes such heavy atoms to give off new spectrum lines must indicate coronal temperatures...
Scientists had formerly assumed the corona to be scarcely hotter than the sun's surface, a mere 10,000° F. Physicist Edlen was so astonished by his own conclusions that he kept them secret for two years while he cleared up all reasonable doubts...