Has the Earth been exposed to numerous supernovae within the last 300 kyr?

Abstract

Firestone (2014) asserted evidence for numerous (23) nearby (d<300 pc) supernovae within the Middle and Late Pleistocene. If true, this would have strong implications for the irradiation of the Earth; at this rate, mass extinction level events due to supernovae would be more frequent than 100 Myr. However, there are numerous errors in the application of past research. The paper overestimates likely nitrate and 14C production from moderately nearby supernovae by about four orders of magnitude. Moreover, the results are based on wrongly selected (obsolete) nitrate and 14C datasets. The use of correct and up-to-date datasets does not confirm the claimed results. The claims in the paper are invalidated.

8 pages, 1 figure. to be published in the Interenational Journal of Astrobiology

References in corpus (3)

• Astrophysical Ionizing Radiation and the Earth: A Brief Review and Census of Intermittent Intense Sources
• Modeling atmospheric effects of the September 1859 Solar Flare
• Galactic Supernova Remnants: an Updated Catalogue and Some Statistics

Cited by in corpus (5)

• A rapid cosmic-ray increase in BC 3372-3371 from ancient buried tree rings in China
• Anchoring historical sequences using a new source of astro-chronological tie-points
• Supernovae and Single-Year Anomalies in the Atmospheric Radiocarbon Record
• Long-Term Prospects: Mitigation of Supernova and Gamma-Ray Burst Threat to Intelligent Beings
• Nitrate Deposition following an Astrophysical Ionizing Radiation