A recent study examines how the Earth was hit by blasts from supernovae (plural form of supernova (SN)) that occurred 3 million years ago (Mya) and 7 Mya with the goal of ascertaining the distances of where these blasts originated. Using the live (not decaying) radioactive isotope 60-Fe, which is produced from supernovae, a team of researchers at the University of Illinois was able to determine the approximate astronomical distances to the blasts, which they refer to as Pliocene Supernova (SN Plio, 3 Mya) and the Miocene Supernova (SN Mio, 7 Mya).
“Supernovae are dramatic examples of the fact that stars have life cycles,” Dr. Brian Fields, who is a Professor of Astronomy at the University of Illinois and a co-author on the study, tells Universe Today. “Supernova explosions mark the spectacular deaths of the most massive stars, those at least eight times the mass of the Sun. They play a central role in astrophysics and cosmology for many reasons.” [Continue reading…]