As we continue to explore the edges of our solar system astronomers continue to discover new celestial bodies that make us rethink what we know about the universe, and a new discovery has shaken us up more than we thought it would the discovery of a new dwarf planet. Called, for now, 2017 OF201 this new planet is so far out that it takes about 25,000 years just to go around the sun once.
It was discovered by a joint team from the Institute for Advanced Study and Princeton University who were looking for something completely different, the elusive and still-hypothetical Planet Nine, a mysterious world believed by some scientists to be several times the size of Earth and hiding far beyond Neptune. This potential celestial body could help explain the odd behaviors and orbits of other distant space object, but it seems to be a lot harder to find than anticipated.
Sihao Cheng, who led the research explains how they found this new catalogued addition to out system “It’s not very different from how Pluto was discovered. This project was really an adventure.”
The new dwarf planet that was found and its place in our solar system
Comparisons are odious, but most of us still have not gotten over the demotion of Pluto, and this 2017 OF201 is quite reminiscent of it. Although it is not exactly the same as Pluto, Cheng calls it an “extreme cousin” of the former planet. It measures an estimated 435 miles in diameter, which is much smaller than Pluto’s roughly 1,500-mile width, but still big enough to be considered a dwarf planet.
What makes it so is that it still orbits the sun and is round-ish, but it has not cleared out the space around it like full-fledged planets do. Its orbit is one of the most curious things about it, as it is quite stretched-out and at its farthest, it drifts more than 1,600 times farther from the Sun than Earth does, which is quite the stretch.
2017 OF201 was found because of archival data of a telescope from Chile, which, although it had been scanning the skies for clues about dark energy, allowed them to spot a faint object slowly moving across the sky. Over time, its motion added up into a clear, consistent orbit.
“We were using public data that has been there for a long time,” said Jiaxuan Li, another member of the team. “It was just hidden there.”
Right now, 2017 OF201 is near its closest approach to the Sun, which gives researchers a small window to do follow-up observations with ground-based telescopes, but researchers will likely need to wait a few weeks before they can get clearer data. Even with this exciting new find, Cheng is not ready to give up on Planet Nine just yet.
“This whole project started as a search for Planet Nine, and I’m still in that mode,” he said. “But this is an interesting story for scientific discovery. Who knows if Planet Nine exists, but it can be interesting if you’re willing to take some risks.”
Ironically, the discovery of 2017 OF201 might complicate things for Planet Nine supporters, as the theory hinges on the idea that the planet’s gravity causes certain icy objects to cluster in specific ways. But this new object doesn’t quite fit into those groupings.
“Under the influence of Planet Nine, all objects that do not have this specific orbital geometry will eventually become unstable and get kicked out of the solar system,” said Eritas Yang, another researcher on the project.
Konstantin Batygin, a planetary scientist at Caltech and one of the original Planet Nine theorists, does not think the new object says much either way about the elusive celestial body. “This object is on a chaotic orbit. So when it comes to the question of ‘What does it really mean for Planet Nine?’ The answer is not very much, because it’s chaotic.”