Scientists have discovered a mysterious new object far beyond Neptune, and it could be one of the most distant dwarf planets ever found.
Named 2017 OF201, this icy world was recently spotted by a team led by Sihao Cheng from the Institute for Advanced Study’s School of Natural Sciences.
Cheng worked with Jiaxuan Li and Eritas Yang from Princeton University to make the discovery using powerful computer tools and publicly available telescope data.
This new object belongs to a group called trans-Neptunian objects (TNOs), which are small planetary bodies that orbit the Sun beyond Neptune.
What makes 2017 OF201 so special is its size and extremely stretched-out orbit.
Scientists estimate it could be around 700 kilometers wide—large enough to be considered a dwarf planet like Pluto, though still much smaller than Pluto’s 2,377 kilometers.
What really stands out is how far it travels from the Sun.
Its orbit takes it 1,600 times farther than Earth at its most distant point and 44.5 times farther at its closest—about the same as Pluto’s average distance.
A single trip around the Sun takes this object roughly 25,000 years!
The object’s strange path suggests it didn’t end up there by accident. Scientists believe it was likely pushed out to the far edges of the solar system after close encounters with a giant planet.
It might have even reached the Oort Cloud, a distant region full of icy bodies, before being sent back inward again.
Interestingly, most extreme TNOs have orbits that line up in a way that some scientists think points to the presence of a hidden giant planet—nicknamed Planet Nine or Planet X. But 2017 OF201 doesn’t follow this pattern. That makes it an important piece of the puzzle and could challenge the idea that Planet Nine exists.
The object was found in images taken by the Victor M. Blanco Telescope and the Canada-France-Hawaii Telescope over seven years. Cheng’s custom algorithm helped identify it in 19 separate images where it appeared as a small moving dot among the stars.
This discovery also suggests that the outer solar system may be more crowded than we thought. Since 2017 OF201 is only visible during about 1% of its orbit, many similar objects could still be hiding out there, too far away for us to detect right now.
Even more exciting, the team made this discovery using open-access data. That means anyone with the right tools and skills—not just professional astronomers—could make similar discoveries, showing how powerful and inclusive modern science can be.
