According to new research published in the journal Icarus, the demoted dwarf planet Pluto may have been formed as the result of a collision between one billion comets. Scientists studying an ice-covered region of Pluto known as Sputnik Planitia noticed the chemical composition of the area is strikingly similar to Comet 67P—both are rich in nitrogen.
"We found an intriguing consistency between the estimated amount of nitrogen inside the glacier and the amount that would be expected if Pluto was formed by the agglomeration of roughly a billion comets or other Kuiper Belt objects similar in chemical composition to 67P, the comet explored by Rosetta," said Dr. Christopher Glein. He and his team have developed what they refer to as 'the giant comet' cosmochemical model of Pluto formation. The scientists also think liquid water likely altered the initial chemical makeup of Pluto.