Overview
- The NSF–DOE Vera C. Rubin Observatory reported the detection of 2026 ED138 after astronomer Matthew Holman flagged the object in images he ran on Oct. 13 and the team recovered matches in about 30 images with precovery frames stretching back to 2016.
- Brightness and distance place ED138 at roughly 46 AU from the Sun and yield a wide diameter estimate of about 600–1,500 km, a range that would make it a dwarf‑planet candidate if its true size and roundness are confirmed.
- Orbital fits show ED138 is a trans‑Neptunian, ‘hot‑classical’ Kuiper Belt object with an inclination near 25 degrees, a pattern consistent with past perturbations by Neptune.
- Follow‑up campaigns are being organized now, including planned thermal/infrared observations and coordinated stellar occultations and proposals for facilities such as JWST and ALMA to nail down size, shape and search for moons.
- If infrared and occultation data show ED138 is in hydrostatic equilibrium, the team will seek formal IAU recognition and a name, and the discovery highlights Rubin’s new survey power to find large objects hidden in crowded Milky Way fields.