- 29 Medien
- hochgeladen 19. Februar 2019
In our galaxy explode in 100 years around 1 to 2 supernovae (SN). Hence chances are high that such a titanic event could have happened during the last 10 Million years close to our solar system, so to speak on our doorstep. The ejected debris of such a close SN should have entered our solar system, and then a fraction must have been deposited on our Earth or on the Moon. A clear signal is exposed by long-living radioisotopes which do not exist naturally on Earth; such as 60Fe (with a half-life of 2.6 Million years). In this presentation I will explain the ultrasensitive detection method (ams, accelerator mass spectrometry) which has been used to detect 60Fe. I will discuss the samples where we have found traces of this radioisotope; in dated deep ocean sediments and ferromanga-nese crusts, and also in lunar regolith, collected during the Apollo missions between 1969 and 1972. The revealed time slot where we found 60Fe deposition, coincide with a drop in Earth’s temperature before about 2 and 3 Million years, which induced major gla-ciations of the Earth. These glaciations are considered as the cause for the development and evolution of mankind. I will discuss possible correlations.