The Vera C. Rubin Observatory has discovered a new potential dwarf planet, designated 2026 ED138, located approximately 4.3 billion miles from the Sun. Mario Jurić, lead solar system scientist at the observatory, announced the find during an International Astronomical Union (I.A.U.) meeting in Spokane, Washington. The discovery marks the largest of about 2,300 objects beyond Pluto identified by the observatory, increasing the known population of such bodies by roughly 50 percent.
The object was detected not by visual inspection but by software developed by Matthew Holman and Kevin Napier, which tracked shifting points across images taken between March and July. The orbit of 2026 ED138 is tilted nearly 25 degrees relative to the planetary plane, and its brightness suggests a diameter between 370 and 930 miles, depending on surface reflectivity. While too distant to confirm roundness, scientists estimate icy bodies over 250 miles in diameter likely qualify as dwarf planets under I.A.U. criteria.
The discovery does not confirm or refute the existence of Planet Nine, but it demonstrates the observatory’s capacity to find distant solar system objects. Holman noted that even if Planet Nine is absent, other large bodies may remain undetected. The last official dwarf planets—Ceres, Pluto, Eris, Haumea, and Makemake—were designated in 2006.
Source: New York Times Top Stories · Summarized by HeadlinesBriefing