Today in History - 185
Some 1,800 years ago, Chinese astronomers witnessed the sudden appearance of a brilliant "guest star." Scientists now widely regard this celestial event, carefully noted in an official history at the time, as the oldest supernova ever recorded. Indeed, researchers have suggested several candidates for the glowing stellar remnant cast off during this apparent supernova, the explosive death of a massive star.
But a new analysis of the historical record suggests the ancient Chinese didn't see a supernova explosion after all. Instead, two radioastronomers now argue, the discovery was in fact a comet.
Astronomer Bradley E. Schaefer of Yale University finds the new report intriguing but says it's too early to settle the controversy. He maintains that the ancient Chinese discovered the object low in the sky just before sunrise. A comet at the reported position would have had to have been very bright to be seen at all. And a bright comet is either unusually large or passing very near Earth. In the latter scenario, the comet couldn't remain visible for as long as 7 months, Schaefer says.
But a new analysis of the historical record suggests the ancient Chinese didn't see a supernova explosion after all. Instead, two radioastronomers now argue, the discovery was in fact a comet.
Astronomer Bradley E. Schaefer of Yale University finds the new report intriguing but says it's too early to settle the controversy. He maintains that the ancient Chinese discovered the object low in the sky just before sunrise. A comet at the reported position would have had to have been very bright to be seen at all. And a bright comet is either unusually large or passing very near Earth. In the latter scenario, the comet couldn't remain visible for as long as 7 months, Schaefer says.
