If and when the nuclear holocaust begins to bring down society as we know it, it isn't the initial blasts you should be worrying about. Carl Sagan and other scientists once hypothesised that dust blocking out the Sun could bring a nuclear winter. It probably happened before - to the dinosaurs.
Tagged With extinctions
Several million years ago, a series of nearby supernovae explosions lit up the sky, rained radioactive particles down on our planet and might have kickstarted a major climactic shift. That's according to a pair of studies published today in Nature, which link radioactive debris spread across the seafloor to cosmic fireworks hundreds of light years away.