A new world may be hiding past Pluto, and it could be bigger than any dwarf planet we already know.
Quick Take
- The Vera C. Rubin Observatory spotted a large, bright object called 2026 ED138 far beyond Pluto’s orbit.
- Scientists call it a dwarf planet candidate, sitting about 46 astronomical units from the Sun.
- Early estimates put its size between 600 and 1,500 kilometers wide, possibly bigger than Ceres.
- Astronomer Matthew Holman found it while testing software built to track distant moving objects.
- Scientists still need infrared data to confirm its true size and official status.
A New Candidate Emerges From The Outer Dark
The National Science Foundation and Department of Energy’s Vera C. Rubin Observatory announced the find on October 27, 2026. Researchers spotted the object, named 2026 ED138, in observation data collected between March and July of that year. The Rubin Observatory called it a large, bright trans-Neptunian object and identified it as a dwarf planet candidate. That label matters. It means scientists see strong signs of something big but haven’t yet nailed down every detail.
Trans-Neptunian means the object orbits farther from the Sun than Neptune does. Right now, ED138 sits roughly 46 astronomical units away. One astronomical unit equals the distance from Earth to the Sun, about 93 million miles. That puts ED138 deep in the frozen edge of our solar system, far past Pluto’s own lonely orbit.
The Man Behind The Discovery And The Machine That Found It
Credit for the discovery goes to Matthew Holman, an astronomer at the Center for Astrophysics, a joint research group run by Harvard and the Smithsonian. Holman works with the Rubin Operations team. He found ED138 while helping build search algorithms designed to hunt for faint, slow-moving objects in the outer solar system. His work shows how modern astronomy now leans heavily on smart software sorting through mountains of telescope images.
Rubin Observatory itself is built for this kind of hunting. During its early test runs, the telescope already discovered more than 11,000 new asteroids, including 380 other trans-Neptunian objects. That track record suggests ED138 will not be the last major find tucked into Rubin’s data streams in the years ahead.
How Big Is Big Enough To Be A Dwarf Planet
CNN reported that scientists estimate ED138’s diameter somewhere between 600 and 1,500 kilometers. That range is wide, but even the low end would place it near the size of some known dwarf planets. The high end would make it noticeably larger than Ceres, the smallest body currently recognized as a dwarf planet and the only one found inside the asteroid belt.
Stanford News independently reported on the discovery the following day, describing ED138 as potentially one of the largest dwarf planet candidates ever found beyond Neptune. That outside confirmation from a separate research institution adds real weight to the initial Rubin announcement, even as the classification itself remains open.
Why Scientists Are Not Calling It Official Yet
Holman has been careful with his words, telling CNN that ED138 is “still a candidate.” Dwarf planet status requires more than size. Scientists must confirm the object is round, shaped by its own gravity into a near-spherical form called hydrostatic equilibrium. Right now, researchers only have early size estimates. They need infrared observations to pin down ED138’s true diameter, surface makeup, and shape.
This process has a history. Pluto itself was classified as a full planet for 76 years before the International Astronomical Union created the dwarf planet category in 2006 and moved Pluto into it. That reclassification did not change what Pluto physically is. It changed how scientists decided to sort objects like it. ED138 may face a similar waiting period before experts settle on its final label.
What Comes Next For 2026 ED138
Astronomers now have a clear to-do list. They need follow-up imaging from other major telescopes to double-check Rubin’s orbit calculations. They need infrared readings to measure heat signatures, which help nail down size and surface material. Finding a moon orbiting ED138 would also help enormously, since a moon’s motion lets scientists calculate the object’s mass through simple physics.
None of that changes what has already happened. Rubin Observatory found a massive object hiding in the dark beyond Pluto, tracked its path for months, and gave it a name. The solar system just got a little more crowded, and a lot more interesting, with one qualified exception: the final chapter on what to officially call 2026 ED138 has not yet been written.
🪐🔭 Scientists Discover a Possible New Dwarf Planet Beyond Pluto! 🌌✨
Did you know that scientists are still discovering large objects in our own Solar System? 🤯
And now, astronomers have found something exciting beyond Pluto!
Researchers using the Vera C. Rubin Observatory… pic.twitter.com/rDlGWU6e1A
— SciTech Talkies (@SciTechTalkies) November 1, 2026
For now, skywatchers and scientists alike have a new object to track. Rubin’s ten-year survey mission has barely started, and ED138 stands as an early reminder of what patient, wide-field telescope work can still find in our own cosmic backyard.
Sources:
foxnews.com, rubinobservatory.org
