If a star were to explode near the Earth, we would be hit with millions of deadly particles and cosmic rays, causing mass extinctions due to the high radiation of cosmic rays, which strips away our planet's protective ozone layer. Astronomers think this happens about every 60 million years (NOTE: Subscribers can still listen to this show).
Some people think that supernovas won't be a problem, but 450 million years ago, our oceans were filled with life--then suddenly over half these species died. Scientists now blame this cosmic rays. The question for us is: Will it happen again?