MLL-Kolloquium: Dr. Gunther Korschinek (Physik Department E15, TUM) : Supernova footprint on the doorstep: 60Fe, 53Mn, and other possible correlations

Lecture Hall (ground floor, west) (LMU Building, Am Coulombwall 1, Garching)

Lecture Hall (ground floor, west)

LMU Building, Am Coulombwall 1, Garching


In our Galaxy, around 1 to 2 supernovae (SN) explode over the course of 100 years. Such a titanic event happened during the last 10 Million years close to our solar system, so to speak on our doorstep.  The ejected debris has entered our solar-system, and a fraction lodged on our Earth and on the Moon. Clear signals are long-living radioisotopes, which do not exist naturally or at low amounts on Earth; such as 60Fe (T1/2 = 2.6 Ma). After a short summary of measurement results of 60Fe, performed at TU-Munich and at ANU (Canberra), I will present first indications of another supernova-formed radioisotope in deep-sea crusts, 53Mn (T1/2 = 3.7Ma). The, so called, local fluff (local interstellar cloud), presently imbedding the solar system, could originate from these close-by SNe, hence should comprise 60Fe that enters the solar system now. Search in 500 kg snow from the Antarctica reveals a signal of 60Fe that supports a recent SN-origin of the local fluff. The time slot where we found 60Fe deposition in crusts and sediments, coincides with a drop in Earth’s temperature, that happened between 2 or 3 Million years before now, and it enforced glaciations on the Earth. These glaciations are considered the cause for the evolution and development of mankind. Possible correlations will be discussed.