New research indicates that meteorites found in Antarctica contain grains of sand formed from a supernova that took place billions of years ago. The supernova may even have been the one that formed our solar system.
It appears as if the meteorites are older than the solar system itself, which was formed 4.6 billion years ago. The chemical signature of the grains found in the meteorites is identical and also quite rare, indicating that both grains derived from the same supernova. The grains are the first to be found in early meteorites and are distinguished by the type of oxygen contained in the silica.
The grains "cannot be explained by any known process acting in the solar system," the study states. "Their isotopic compositions can only be explained by nuclear reactions occurring in stellar environments."
"It's a bit like learning the secrets of the family that lived in your house in the 1800s by examining dust particles they left behind in cracks in the floorboards," a Washington University news release states.
The grains of the meteorites were discovered by two scientists. Since the grains cannot be detected without instrumentation, Washington University in St. Louis graduate student Pierre Haenecour used a NanoSIMS 50 ion microprobe to detect one. The instrument magnifies objects 20,000 times. The other grain was detected by Xuchao Zhao, a scientist at the Institute of Geology and Geophysics in Beijing, who was studying a meteorite found by the Chinese Antarctic Research Expedition.
The find has important implications not only for the understanding of supernovae but also the origin of our solar system. It follows the recent determination that green meteorites found in Morocco last year may be the first ever to come from the planet Mercury.
The findings of the study are published in the May 1 issue of Astrophysical Journal Letters.