Word: supernovas
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Another question that troubled some astronomers was why 1987A stopped brightening. To be sure, some previously observed supernovas have leveled off in brightness for a time, then shot up to the expected brilliance. In fact, last week southern hemisphere observatories reported that the supernova's magnitude, which had remained relatively constant for almost two weeks, showed signs of increasing slightly, from 4.5 to 4.25. But even if 1987A stays "subluminous," it will be important because it may point to the existence of a previously unknown class of stellar explosion...
What does it all mean? "There will be as many notions of what's going on as there are astronomers," says Woosley. "It's what you might call organized scientific chaos. When it's all over, we'll have a better idea of what causes a supernova, but the one rule now is that you shouldn't trust the theoreticians. Expect the unexpected...
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...
Sure enough, a check of the Kamiokande II detector in Japan disclosed that a burst of eleven neutrinos, with the predicted range of energies, arrived in a span of 13 seconds on Feb. 23, about three hours before light from the supernova was first observed. And data provided by the IMB (Irvine-Michigan- Brookhaven) detector under Lake Erie showed a burst of eight neutrinos in six seconds at the same time as the Japanese reading. Says Physicist Frederick Reines, of the University of California, Irvine: "One observation by one team is not sufficient; it has to be confirmed...
...thus the earth -- would die. Nonetheless, he was basically correct: first fire, then ice. The fire will not be an explosion like the one now brightening the Large Magellanic Cloud; the sun is thought to have only about a tenth of the mass necessary to become a Type II supernova and has no stellar companion to contribute the mass necessary to turn it into a Type I blast. But that will be of little comfort to whatever creatures exist on earth when the sun is in its death throes; the $ final solar convulsions, while feeble compared to those...