What Happens If A Star Explodes Near The Earth

People have witnessed supernovae for millennia, but what threat do they pose to life on Earth This video is sponsored by Brilliant. You can get started for free, or the first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription. ▀▀▀ A massive thanks to Prof. Hans-Thomas Janka for helping us with the physics of supernovae and GRBs. A massive thanks to Prof. Brian Thomas for all of his help with the terrestrial effects of supernovae and GRBs. This video would not have been possible without them. Also thanks to Dr. Luke Barnes for his initial help with the literature search. Hydrogen bomb vs Supernova fact was taken from this great article by xkcd/Randall Munroe – https://what-if.xkcd.com/73/ (based on the calculation by Andrew Karam, 2002) Cosmic bubble footage from https://www.cfa.harvard.edu/news/1000-light-year-wide-bubble-surrounding-earth-source-all-nearby-young-stars Neutrino driven SN explosion simulations from https://iopscience.iop.org/article/10.1088/2041-8205/808/2/L42 ▀▀▀ References: Melott, A. et al. (2019). Hypothesis: Muon radiation dose and marine megafaunal extinction at the End-Pliocene supernova. Astrobiology, 19(6), 825-830. – https://ve42.co/Melott1 Thomas, B. C. et al. (2016). Terrestrial effects of nearby supernovae in the early Pleistocene. The Astrophysical Journal Letters, 826(1), L3 – https://ve42.co/Thomas1 Melott, A. L., & Thomas, B. C. (2019). From cosmic explosions to terrestrial fires. The Journal of Geology, 127(4), 475-481. – https://ve42.co/Melott2 Fields, B. et al. (2019). Near-Earth supernova explosions: Evidence, implications, and opportunities. arXiv preprint arXiv:1903.04589. – https://ve42.co/Fields1 Thomas, B. C., Atri, D., & Melott, A. L. (2021). Gamma-ray bursts: not so much deadlier than we thought. Monthly Notices of the Royal Astronomical Society, 500(2), 1970-1973. – https://ve42.co/Thomas2 Melott, A. et al. (2004). Did a gamma-ray burst initiate the late Ordovician mass extinction. Internatio