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Ways the world could end: NASA edition

By: Katherine Butler on Feb. 16, 2012, 5:56 p.m.

Photo: European Space Agency and Justyn R. Maund

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Supernova: When the sky explodes

A supernova occurs in space when a supergiant star explodes, sending out almost incomprehensive amounts of energy. One expert measures this energy as “total output of the sun during its 10 billion year lifetime.” Further, experts believe that a supernova “within 100 light-years of the Earth would likely be a catastrophic event for our planet.” Has such an event ever happened in Earth’s history? Around 250 million years ago, a mysterious mass extinction took place on Earth. It is referred to as the Permian-Triassic extinction, or “The Great Dying.” Some experts hypothesize that a supernova blast may have caused the extinction.