Vera C. Rubin Observatory discovers dwarf planet candidate 2026 ED138

Astronomers using the NSF–DOE Vera C. Rubin Observatory have identified a massive trans-Neptunian object, designated 2026 ED138, which is a candidate for the solar system’s sixth dwarf planet. The icy body is estimated to be between 600 and 1,500 kilometers across and is located approximately 46 astronomical units from the Sun, placing its orbit beyond that of Pluto.

The object was detected by Matthew Holman of the Center for Astrophysics | Harvard & Smithsonian using specialized software designed to identify moving objects against the dense background of the Milky Way. The discovery was made possible by the observatory’s ability to process vast amounts of data and its high-precision monitoring. Researchers were able to extend the object's observed timeline by locating it in archival images dating back to 2016.

If officially confirmed by the International Astronomical Union, 2026 ED138 would join Pluto, Ceres, Eris, Haumea, and Makemake as a recognized dwarf planet. Scientists believe the object may have been flung into its current wide orbit by gravitational interactions with Neptune billions of years ago.