Investigate the influence of astronomical phenomena on the Earth

Fabo Feng (March 28, 2019)

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Abstract

Previous studies claimed various periodicity in the biodiversity variation recorded by fossils and the paleo-geological data. Considering the influence of various astronomical phenomena such as cosmic rays, asteroid impacts, and supernova explosion on the Earth, we build astronomical models of mass extinctions, climate change, and terrestrial impact rate. The occurrence rate of such phenomena are typically modulated by the motion of the Sun in the Galaxy and the motion of the Earth in the Solar System. We investigate the uncertainty in the motions of the Sun and the Earth and account for such uncertainty in Bayesian model comparison. By comparing the astronomical models with null hypotheses, we find strong connection between the Earth’s obliquity and the terrestrial climate change (so-called "Milankovitch cycle") but failed to find strong influence of the solar motion on various terrestrial records. Thus the solar motion at most plays a minor role in the triggering of terrestrial mass extinctions.