Exploding Star Missing From Formation of Solar System
A new study challenges the notion that the force of an exploding star forced the formation of the solar system. University of Chicago researchers Haolan Tang and Nicolas Dauphas found the radioactive isotope iron 60 — the telltale sign of an exploding star—low in abundance and well mixed in solar system material. As cosmochemists, they look for remnants of stellar explosions in meteorites to help determine the conditions under which the solar system formed. Some remnants are radioactive isotopes: unstable, energetic atoms that decay over time.
Scientists in the past decade have found high amounts of the radioactive isotope iron 60 in early solar system materials. “If you have iron 60 in high abundance in the solar system, that’s a ‘smoking gun’—evidence for the presence of a supernova,” said Dauphas, professor in geophysical sciences. Iron 60 can only originate from a supernova, so scientists have tried to explain this apparent abundance by suggesting that a supernova occurred nearby, spreading the isotope through the explosion. The study was published online in Earth and Planetary Science Letters.