Pluto has been intriguing astronomers and space-lovers for decades, and ever since New Horizons visited the distant, icy world in 2015, we’ve been learning more about it than ever before. We’ve also been learning more about the various other planets, asteroids, comets, and other bodies in the solar system thanks to an extensive network of spacecraft built by NASA and ESA.

A new study by scientists at the Southwest Research Institute used information from two of these spacecraft, NASA’s New Horizons and the ESA’s Rosetta, to develop a unique theory of Pluto’s origins. According to the idea, Pluto was formed from the remains of a billion icy comets in the early days of the solar system.

While New Horizons spent a decade racing to visit some of the most distant objects in the solar system, Rosetta explored a single comet called 67P that spent the last few years a little closer to the sun. Studying this ball of ice can tell us a great deal about what other comets in the outer solar system are like.

Comparing results from New Horizons and Rosetta, the researchers noticed similarities in their makeup. Both Pluto and Comet 67P were made of the same stuff, which suggests that Pluto came from some comets a long time ago. Specifically, the researchers examined the heart-shaped glacier on Pluto’s surface, named Sputnik Planum, and compared the nitrogen levels inside the ice to the nitrogen levels inside 67P.

“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,” says study author Christopher Glein in a press release.

This content is created and maintained by a third party, and imported onto this page to help users provide their email addresses. You may be able to find more information about this and similar content at piano.io