Word: pulsars
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Dates: during 1980-1989
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Scientists have been able only to theorize about the origin of pulsars, those superdense, fast-spinning celestial objects that appear to blink on and off as % often as every millisecond. Now the mystery seems to be solved. Last week an international team of astronomers announced that they had detected a pulsar emerging from the murky dust clouds left over from Supernova 1987A, a giant star that exploded about 170,000 light-years from earth and was first seen two years...
Astronomers have long believed that pulsars are produced by stellar explosions. Until now, though, no pulsar had been observed so soon after its birth. The first pulsar was discovered in 1967, its radio signals so regular that they were suspected of coming from an alien civilization. Several hundred pulsars have since been found...
Because the new pulsar is so young, it is spinning almost unimaginably fast. Its "day" is only one two-thousandth of a second long, and while the earth's equator rotates at about 1,000 m.p.h., the pulsar's is moving at more than 200 million m.p.h. By rights, the pulsar should fly apart, but it is so dense -- a teaspoon of it would weigh 300,000 tons on earth -- that its gravity holds it together. Says Richard Muller of Lawrence Berkeley Laboratory, a member of the discovery team: "We can't help being astounded by what we are seeing...
...decaying cobalt 56 should start showing up this summer. Concedes Woosley: "I'm out on a limb." A more radical theory, put forth by Princeton Astrophysicist Jeremiah Ostriker, proposes that the neutron star that formed at 1987A's center when Sanduleak exploded has turned into an extremely rapidly rotating pulsar that is leaking energy and illuminating the surrounding debris...
...long it takes for a pulsar to develop is one puzzle 1987A may help answer. In addition, says Taylor, scientists would like to learn what kind of supernovas make pulsars. "We have a good idea that stars between eight and 15 times the mass of the sun are in the right range," he says, "but that is still somewhat speculative...