Time-Resolved Two Million Year Old Supernova Activity Discovered in the Earth’s Microfossil Record
by
Prof.Shawn Bishop(Physik Department E12 Technische Universität München)
→
Europe/Berlin
Auditorium (MPI fuer Physik)
Auditorium
MPI fuer Physik
Description
Using accelerator mass spectrometry, we have conducted a search for live, supernova-produced, 60Fe atoms within biogenically produced magnetite (Fe3O4) crystals contained in two Pacific Ocean sediment cores. We have found a time-resolved 60Fe signal in both sediment cores, above background, centered at approximately 2.1 Myr ago and spanning approximately 800 kyr duration (full width half maximum). The onset of this signal coincides with a known marine extinction event at the Pleiocene/Pleistocene boundary, and its shape will require eventual astrophysical interpretation to understand.
