Astronomers Discover Giant New Dwarf Planet Candidate Beyond Pluto
What Happened
Astronomers using the Vera C. Rubin Observatory have discovered 2026 ED138, a large trans-Neptunian object orbiting beyond Pluto. Early estimates suggest it could be roughly 600-1,500 km across, potentially placing it among the largest dwarf-planet candidates found in the outer Solar System. The object was discovered by astrophysicist Matthew Holman in Rubin data, with researchers subsequently identifying observations dating back to 2016. Its location against the crowded background of the Milky Way may help explain why it escaped detection until now.
Key Takeaways
2026 ED138 is only a dwarf-planet candidate for now. Further observations are needed to establish its physical characteristics before it could potentially join the five dwarf planets currently recognised by the International Astronomical Union: Ceres, Pluto, Eris, Haumea and Makemake.