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Pluto is not a planet – it's a billion comets squished together

点击量:   时间:2019-03-06 09:08:01

NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute By Leah Crane Pluto might be made of a billion comets squashed together. Its chemical makeup hints that this might be its origin story, and that it may even have once had a liquid ocean. Pluto is chock full of nitrogen. Currently, it is found in gas form in Pluto’s tenuous atmosphere, and in solid form in giant glacier made of nitrogen-rich ice, called Sputnik Planitia,