Overview
- Researchers from Harvard and the Vera C. Rubin Observatory announced the provisional discovery of 2026 ED138 at the Division for Planetary Sciences meeting in Spokane on Tuesday.
- Initial data place 2026 ED138 about 46 astronomical units from the Sun with an orbital tilt near 25 degrees and a diameter estimated between 600 and 1,500 kilometers.
- The object was found by running Rubin survey data through search code developed by Matthew Holman and Kevin Napier and by linking more than 30 Rubin observations from March–July 2026 with archival images back to 2016.
- Astronomers stress that follow-up work is required to confirm dwarf‑planet status, including higher‑resolution imaging, thermal measurements, light curves, and possible occultation observations to test whether the body is in hydrostatic equilibrium.
- If confirmed, ED138 would join the small group of recognized dwarf planets and highlight how Rubin’s wide, repeated deep imaging and archival searches can reveal large bodies hidden in crowded Milky Way starfields.