Researchers May Have Discovered the 6th Dwarf Planet Candidate ED138

Researchers from the Vera C. Rubin Observatory have reported the discovery of a potential new dwarf planet candidate named ED138. The object was identified in October when team member Matthew Holman spotted an unusually large moving object using a program developed with colleague Kevin Napier to scan observatory data. Holman subsequently verified the findings across archived data and external services, tracing observations back to 2016. The object has been submitted to the International Astronomical Union’s Minor Planet Center for further analysis to determine its official classification.

Understanding Dwarf Planets and the Discovery of ED138

Dwarf planets are extremely rare in our solar system, with only five currently recognized examples: Pluto, Eris, Haumea, Makemake, and Ceres. ED138 is being evaluated as a potential sixth candidate because preliminary estimates indicate it possesses properties consistent with dwarf planets:

• Location: It orbits farther from the sun than Neptune, categorizing it as a trans-Neptunian object.
• Size and Shape: Preliminary estimates suggest the icy body is between 600 and 1,500 kilometers wide, which is expected to be large enough for self-gravity to pull it into a round shape.
• Orbital Characteristics: Like other dwarf planets, it has not cleared its orbit of space debris.

Practical Implications and Verification

The discovery highlights the capabilities of modern sky surveys. The Rubin Observatory has submitted thousands of asteroid discoveries since it began scanning in June 2025. Researchers note that ED138 is located against the crowded starry backdrop of the Milky Way, which likely caused it to remain unnoticed in older telescope observations.

To verify official updates regarding ED138, readers can consult announcements from the International Astronomical Union’s Minor Planet Center or official publications from the Vera C. Rubin Observatory.