Word: supernova
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...name astronomers gave to known neutron stars: pulsars. The spinning neutron stars have intense magnetic fields generating precisely spaced electromagnetic pulses that can be picked up by radio telescopes. Some 440 pulsars have been discovered so far, all of them thought to be remnants of Type II supernovas. The youngest found to date sits right at the center of the Crab nebula, site of the great supernova...
...little wonder, then, that within hours of 1987A's discovery, an extraordinary array of scientific brainpower and hardware was brought to bear on the celestial phenomenon. Throughout the southern hemisphere (the supernova is not visible in northern skies), in South America, Australia and South Africa, telescopes of every size were focused on the bright newcomer in the Large Magellanic Cloud. NASA promptly ordered some of its satellites to do the same. On its way to a rendezvous with Neptune in 1989, the Voyager 2 spacecraft pointed its two ultraviolet-light detectors at the supernova. The Solar Max satellite turned...
...mine in Japan, in the Mont Blanc Tunnel linking Italy and France, and in 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...
...data than they could immediately analyze, confirming some theoretical predictions and making several observations that for the time being puzzled everyone. Earliest readings showed that the shell of gases expanding around 1987A was initially traveling outward at nearly 10,000 miles per second. Since then the color of the supernova has been changing from blue to red much faster than expected. "That change is five to ten times faster than other supernovas," says Robert Williams, director of the U.S.-financed Cerro Tololo Inter-Observatory in Chile. This phenomenon indicates that the rapid expansion of the shell is causing...
Those early characteristics lead Williams to speculate that 1987A "may have had an antecedent star that was not that massive, as supernovas go." By comparing the supernova's position with older photographs of the Large Magellanic Cloud, many astronomers at first identified a hot blue supergiant star, called SK-69 202, as the probable progenitor of 1987A. But that conclusion troubled everyone; theory holds that a star with these characteristics is too young to expire in a final explosion. Two weeks ago, as the initial ultraviolet radiation from the blast began to die down, the astronomers breathed a collective sigh...