New Minor Planet Found at the Edge of the Solar System

New Minor Planet Found at the Edge of the Solar System

2017 OF201 is a freshly christened “minor planet” living way off in the outskirts of our solar system. It’s huge, cold, and its orbit is enormous. First spotted lurking in archival data by a team led by Sihao Cheng of the Institute for Advanced Study, 2017 OF201 finally earned some legitimacy from the International Astronomical Union on May 21. It’s got a diameter that could be anywhere from 290 to 510 miles. If it’s closer to the 510, that mean…

New minor planet found in the distant solar system

These are the orbits of 96 minor planets and extreme trans-Neptunian objects around the sun. On May 21, 2025, the Minor Planet Center announced a new minor planet in orbit around the sun: 2017 OF201. This is one of the largest solar system objects discovered in the past decade. But it’s still not Planet 9. Image via Nrco0e/ Wikimedia Commons. (CC BY-SA 4.0) Looking up has never felt more important. Please donate to help EarthSky keep bringing th…