Thursday, September 09, 2010
Supernova Shrapnel Found in Meteorite
Scientists have identified the microscopic shrapnel of a nearby star that exploded just before or during the birth of the solar system 4.5 billion years ago.
Faint traces of the supernova, found in a meteorite, account for the mysterious variations in the chemical fingerprint of chromium found from one planet and meteorite to another. University of Chicago cosmochemist Nicolas Dauphas and eight co-authors report their finding in the late Sept. 10, 2010 issue of the Astrophysical Journal.
Scientists formerly believed that chromium 54 and other elements and their isotopic variations became evenly spread throughout the cloud of gas and dust that collapsed to form the solar system. “It was a very well-mixed soup,” said Bradley Meyer, a professor of astronomy and astrophysics at Clemson University who was not a co-author of the study. “But it looks like some of the ingredients got in there and didn’t get completely homogenized, and that’s a pretty interesting result.”