Terrestrial effects of moderately nearby supernovae

Abstract

Abstract-Recent data indicate one or more moderately nearby supernovae in the early Pleistocene, with additional events likely in the Miocene. This has motivated more detailed computations, using new information about the nature of supernovae and the distances of these events to describe in more detail the sorts of effects that are indicated at the Earth. This short communication/review is designed to describe some of these effects so that they may possibly be related to changes in the biota around these times. Adrian L. Melott

Climate change via CO2 drawdown from astrophysically initiated atmospheric ionization?

“…If we add in the cosmic ray trapping effect of the magnetic field in the walls of the Local Bubble and/or multiple supernovae (Breitschwerdt et al ., 2016) the duration of the effect may be greater. Muon irradiation has the additional effect of affecting life up to a kilometre below the surface of the ocean (Melott and Thomas, 2018; Melott et al ., 2019). Nevertheless, only a small increase in mutation and carcinogenesis is expected for phytoplankton, although the effect may be large for megafauna (Melott et al ., 2019).…”

“…(1999). Recent studies of the effects upon the Earth of such an event have included enhanced solar ultraviolet-B (UVB 280–315 nm) due to ozone depletion, visible light effects on nocturnal organisms, increased radiation from cosmic ray secondaries (primarily muons and neutrons) and direct deposition of cosmogenic radioisotopes (Melott et al ., 2017; Melott and Thomas, 2018; Thomas, 2018; Melott et al ., 2019).…”