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Boffin's software found a possible dwarf planet - a result so rare he thought it must be a bug

Space2 min read

A scientist using software built for the Rubin Observatory in Chile may have found a new dwarf planet, called 2026 ED138. It is far out past Neptune and may be the smallest dwarf planet ever seen.

A possible new dwarf planet

A researcher working with data from the Rubin Observatory found a strong candidate for the Solar System's sixth known dwarf planet. The object is named 2026 ED138. The software that found it was so good at spotting rare things that the researcher first thought it might be a mistake. After checking, the team confirmed the find, and the Minor Planet Center published data about its path around the Sun.

Key facts

  • 2026 ED138 orbits at about 46 astronomical units (au). One au is the distance from Earth to the Sun.
  • Pluto's orbit averages about 40 au.
  • Scientists think the object is between 600 and 1,500 kilometers across.
  • If it is 600 km wide, it would be the smallest dwarf planet yet seen.
  • The data included ten years of older records.

What is a dwarf planet?

A dwarf planet is a round object that orbits the Sun. It is not big enough to clear other debris out of its path, so it is not a full planet. Dwarf planets share their orbit area with many rocky and icy objects. The Rubin Observatory is in Chile. It is run by the US National Science Foundation and Department of Energy, and it uses a very large camera to scan the sky.

Why it matters

Finding a dwarf planet this far away is rare. It was hidden because it sits near the flat band of our galaxy, the Milky Way, where billions of stars make it hard to pick out moving objects. The find shows that new tools can reveal hidden parts of our Solar System. If confirmed, it would be a new member of this small group of dwarf planets.

What to watch

  • Whether the object is officially certified as a dwarf planet.
  • Better measurements of its exact size.
  • More observations from the Rubin Observatory as it scans the southern sky.
  • Whether other hidden objects are found with the same software.

Glossary

Rubin Observatory
A telescope facility on a remote hilltop in Chile, run by the US National Science Foundation and Department of Energy, that scans the sky.
Minor Planet Center
An organization that collects and publishes data on small objects in the Solar System, such as newly found asteroids and dwarf planets.
dwarf planet
A round object that orbits the Sun but has not cleared its orbit of other debris.
Milky Way
The galaxy that our Sun and Earth belong to, seen as a band of stars across the night sky.

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