Posted on 05/23/2025 9:22:44 AM PDT by Red Badger
Astronomers just found a frozen world on a 25,000-year orbit—hidden in plain sight and ready to rewrite the outer solar system.
================================================================
Image Credit: images of dwarf planets from NASA/JPL-Caltech; image of 2017 OF201 from Sihao Cheng et al. | The Daily Galaxy --Great Discoveries Channel
=================================================================
A distant, icy world has just been added to our solar system’s official roster, and its strange orbit might challenge one of the biggest space mysteries of our time. According to a study published on arXiv, the object—known as 2017 OF201—is not just any distant rock. It’s a trans-Neptunian object (TNO) that could potentially be classified as a dwarf planet, orbiting the Sun once every 25,000 years. The discovery, announced by the International Astronomical Union’s Minor Planet Center on May 21, 2025, could drastically reshape our understanding of the outer solar system and raise major questions about the controversial Planet 9 hypothesis.
A Hidden Giant in the Outer Solar System
At an estimated 700 kilometers (435 miles) in diameter, 2017 OF201 is roughly a third the size of Pluto, but its orbital path is far more extreme. This icy body travels in an enormous elliptical orbit with a perihelion (its closest approach to the Sun) of 44.5 astronomical units (AU) and an aphelion (its furthest point) of over 1,600 AU—a staggering distance. For context, Earth’s orbit is 1 AU. That vast orbital range means the object is practically invisible to us most of the time. “2017 OF201 spends only 1 percent of its orbital time close enough to us to be detectable. The presence of this single object suggests that there could be another hundred or so other objects with similar orbit and size; they are just too far away to be detectable now,” said Sihao Cheng from the Institute for Advanced Study, who led the discovery team.
Telescope Tech Meets Cosmic Luck
Despite groundbreaking advances in telescope technology, this discovery was not made with a next-gen observatory but with archival data—publicly available records from previous sky surveys. “Even though advances in telescopes have enabled us to explore distant parts of the universe, there is still a great deal to discover about our own Solar System,” Cheng added. The fact that such a significant object remained hidden in plain sight for so long suggests that our own cosmic backyard still holds secrets waiting to be uncovered. The orbit of 2017 OF201 is so extreme and its visibility window so narrow that its discovery required both technical savvy and a bit of astronomical serendipity.
Image showing the current location of Pluto, Neptune, and 2017 OF201. Image Credit: Jiaxuan Li and Sihao Cheng
====================================================================
Planet 9 May Be in Trouble
The orbit of 2017 OF201 doesn’t just add a new name to the solar system; it throws a wrench into the Planet 9 hypothesis—a theory proposing a large, unseen planet far beyond Pluto that influences the orbits of TNOs. While many extreme TNOs appear to be clustered in specific orbital alignments, 2017 OF201 defies this pattern. “Many extreme TNOs have orbits that appear to cluster in specific orientations, but 2017 OF201 deviates from this,” explained Jiaxuan Li from Princeton University, co-author of the discovery. If more objects like this are found—objects that break the clustering pattern—it could dismantle the logic behind Planet 9 altogether. What was once thought to be gravitational proof of a hidden ninth planet might just be statistical noise caused by limited sampling.
The Democratization of Discovery
Perhaps the most inspiring element of this discovery is how it was made. “All the data we used to identify and characterize this object are archival data that are available to anyone, not only professional astronomers,” Li said. “This means that groundbreaking discoveries aren’t limited to those with access to the world’s largest telescopes. Any researcher, student, or even citizen scientist with the right tools and knowledge could have made this discovery, highlighting the value of sharing scientific resources.” In a field often dominated by billion-dollar equipment and elite institutions, this find serves as a powerful reminder: the next big discovery could come from anyone, anywhere—with a laptop and a passion for the stars.
It's really a religion with some folks.
Who do they think they Ar? Jason and the Hughgonauts?
Then don’t classify this new object as a planet either.
Got it.
Mondas.
I hope nothing bumps into 2017 OF201 that changes its elliptical orbit to set up a disastrous chain reaction threatening Earth. I hope the scientists are looking at that possibility.
Trans Neptune Orbit ... what are its pronouns?
Just don’t say Barada Nikto.
That is very unlikely to happen. The new object, assuming it is large enough to be gravitationally rounded, would almost certainly be a dwarf planet, not a planet.
The orientation or longitude of perihelion of 2017 OF201's orbit does not align with other extreme TNOs like Sedna, whose orbits are thought to be clustered because of the gravitational influence of a distant massive planet, dubbed Planet Nine. Simulations run by Cheng's team suggest that Planet Nine would have ejected 2017 OF201 from its current orbit within 100 million years, though 2017 OF201's current orbit could be a temporary state.[6][1][8] Konstantin Batygin, the co-author of the Planet Nine hypothesis, argued that the discovery of 2017 OF201 means nothing in relation to the hypothesis because the object's orbit is significantly influenced by Neptune.[10] Cheng, however, notes that 2017 OF201 "is right at the boundary between being stable and unstable."[10] Nevertheless, Cheng's team agree that their simulations do not disprove Planet Nine.[6] In an interview with The New York Times, Cheng "still thought Planet Nine was possible" while Yang "was neutral on Planet Nine's existence."[6] Li initially thought "OK, this kills Planet Nine" upon seeing 2017 OF201's orbit, but later conceded that the results were not definitive, jokingly stating that "it's 49 percent killed."Implications for the Planet Nine hypothesis
Wikipedia page for 2017 OF201
We report the discovery of a dwarf planet candidate, 2017 OF201, currently located at a distance of 90.5 au. Its orbit is extremely wide and extends to the inner Oort cloud, with a semi-major axis of 838 au and a perihelion of 44.9 au precisely determined from 19 observations over seven years. Assuming a typical albedo of 0.15, we estimate a diameter about 700 km, making it the second-largest known object in this dynamical population and a likely dwarf planet. Its high eccentricity suggests that it is part of a broader, unseen population of similar objects totaling about 1 % of Earth's mass. Notably, the orbit of 2017 OF201 lies well outside the clustering of longitude of perihelion observed in extreme trans-Neptunian objects, which has been proposed as dynamical evidence for a distant, undetected planet.Discovery of a dwarf planet candidate in an extremely wide orbit: 2017 OF201Sihao Cheng, Jiaxuan Li, Eritas Yang | Cornell University
Submitted on 21 May 2025
Astronomers Were Looking for Planet NineAstronomers have just identified what could be a new dwarf planet using observations from the Dark Energy Camera in Chile and the Canada-France-Hawaii Telescope. The discovery wasn't made through a single lucky image, but by carefully analyzing seven years of archival data, which revealed nineteen separate detections, enough to reconstruct its orbit.
when this Guy Showed Up in the Telescope Image | 13:11
Territory | 61.3K subscribers | 58,569 views | June 10, 2025
And once they mapped it out, they found the object follows an extreme orbit. 2017 OF201 travels in a long elliptical path around the Sun. At its closest, it comes in at about 44.5 astronomical units, just a bit beyond Pluto. But at its farthest? It swings out past 1,600 AU. For scale, that's over 50 times farther than Neptune. One orbit takes about 25,000 years.
That's not just far. That's outer Oort Cloud territory!
The ellipse is always symmetrical. The other focus would be at the opposite side of the ellipse, at the same distance to the ellipse itself. Just draw a straight line through the entire ellipse, intersecting the perihelion and the Sun.
In the above image, the foci are at F and F'.
In the case of a perfectly circular orbit, the two foci collapse to a single point.
Regards,
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.