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Interstellar cloud could have wiped out the dinosaurs

作者:陈迎    发布时间:2019-03-07 10:19:01    

Lynn Hilton/Alamy Stock Photo A nebular winter could have doomed the dinosaurs. The clue is a thick layer of an extraterrestrial element on the ocean floor, now claimed to be the result of Earth colliding with a galactic cloud. The most-heard explanation for the dinosaurs’ demise is an asteroid impact, which left a crater off the coast of Mexico and a worldwide 30-centimetre-thick layer of iridium, an element otherwise rare on Earth. But every so often, astronomers suspect,

 

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