2005/03/31 by Adrian L. Melott, Brian C. Thomas, D. P. Hogan +4
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Gamma-ray bursts and supernovae #Pulsars and Gravitational Waves Research #astro-ph #physics.ao-ph #physics.geo-ph #physics.space-ph #q-bio.PE
paper · pdf · doi:10.1029/2005gl023073
published as Geophys.Res.Lett. 32 (2005) L14808 · 12 pages, 2 figures, in press at Geophysical Research Letters. Minor revisions, including details on falsifying the hypothesis
arxiv created 2005/06/27 · openalex publication_date 2005/07/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It is likely that one or more gamma ray bursts within our galaxy have strongly irradiated the Earth in the last Gy. This produces significant atmospheric ionization and dissociation, resulting in ozone depletion and DNA‐damaging ultraviolet solar flux reaching the surface for up to a decade. Here we show the first detailed computation of two other significant effects. Visible opacity of NO 2 is sufficient to reduce solar energy at the surface up to a few percent, with the greatest effect at the poles, which may be sufficient to initiate glaciation. Rainout of dilute nitric acid could have been important for a burst nearer than our conservative “nearest burst”. These results support the hypothesis that the characteristics of the Late Ordovician mass extinction are consistent with GRB initiation.