Word: astrophysicists
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Dates: during 1980-1989
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...another tunnel under Mount Elbrus in the Soviet Union, scientists carefully examined data from computer printouts. They were hoping that some of the ethereal particles called neutrinos, predicted by theory to be produced during a supernova, had penetrated the earth, leaving their trail in huge liquid- filled neutrino detectors. Astrophysicist J. Craig Wheeler, of the University of Texas in Austin, summarized the activity while addressing a hastily convened meeting of astronomers at NASA's Goddard Space Flight Center the week after the discovery, "These are frantic times...
...intermediate steps when the stellar material is compressed so much that its atoms virtually touch, forming what physicists call degenerate matter; what prevents further collapse is the tendency of the atoms' negatively charged electrons to repel one another. The star has become a white dwarf. Says David Branch, an astrophysicist at the University of Oklahoma: "It's the size of the earth but has the mass...
...powerful gravity can draw gaseous matter away from its companion. In some cases, as the dwarf becomes bloated with its companion's substance, gravitational pressure triggers a fusion reaction in the captured gases, which are blown off in the explosion, resulting in a garden-variety (nonsuper) nova. According to Astrophysicist Branch, about 50 novas are observed flaring up each year in the Milky...
...core is fused into iron, the thermonuclear reactions stop. Without enough radiation pressure to sustain it, the now all-iron core, hidden under the star's outer layers, begins its final, catastrophic collapse. In the incredibly short time of just 1 second, according to University of Arizona Astrophysicist Adam Burrows, the core is compressed to more than the density of an atomic nucleus. "It's as if the earth had suddenly collapsed to the size of New York City," says Burrows. "At this point the rest of the star is oblivious. It doesn't know the core has collapsed...
Still, the theoreticians could crow that in at least one way 1987A had performed according to the script. Minutes after hearing about the supernova but before they learned of any neutrino data, Astrophysicist Bahcall and two Israeli colleagues began working on a paper predicting the number of supernova neutrinos that should have been recorded by various detectors on earth; their paper was published in last week's Nature. If the neutrinos had been recorded -- and especially if they arrived before the supernova was seen -- it would be a dramatic confirmation of current supernova theory...