Two new papers appearing in the journal Nature this week are "slam-dunk" evidence that energies from supernovae have buffeted our planet, according to astrophysicist Adrian Melott of the University of Kansas.
Melott offers his judgment of these studies in an associated letter, entitled "Supernovae in the neighborhood," also appearing this week in Nature.
One paper, authored by Anton Wallner and colleagues, proves the existence of ancient seabed deposits of iron-60 isotopes, tracing their source to supernovae occurring about 325 light years from Earth. The second paper, by a team headed by Deiter Breitschwerdt, estimates explosion times of these supernovae, isolating two events: one 1.7 to 3.2 million years ago, and the other 6.5 to 8.7 million years ago.
Two new papers appearing in the journal Nature this week are "slam-dunk" evidence that energies from supernovae have buffeted our planet, according to astrophysicist Adrian Melott of the University of Kansas.
Melott offers his judgment of these studies in an associated letter, entitled "Supernovae in the neighborhood," also appearing this week in Nature.
One paper, authored by Anton Wallner and colleagues, proves the existence of ancient seabed deposits of iron-60 isotopes, tracing their source to supernovae occurring about 325 light years from Earth. The second paper, by a team headed by Deiter Breitschwerdt, estimates explosion times of these supernovae, isolating two events: one 1.7 to 3.2 million years ago, and the other 6.5 to 8.7 million years ago.
"This research essentially proves that certain events happened in the not-too-distant past," said Melott, a KU professor of physics and astronomy. "They make it clear approximately when they happened and how far away they were. Knowing that, we can consider what the effect may have been with definite numbers. Then we can look for events in the history of the Earth that might be connected to them."
Melott said both supernovae events were beyond the "kill zone" of roughly 30 light years, but they might have had other impacts -- including influence on human evolution.
Supernova image via Shutterstock.
Read more at EurekAlert.
