Rare Trans Neptunian Object Reveals Unexpected Orbital Dance with Neptune

Rare Trans Neptunian Object Reveals Unexpected Orbital Dance with Neptune
by Clarence Oxford
Los Angeles CA (SPX) Jul 22, 2025

A rare celestial body drifting far beyond Neptune, designated 2020 VN40, has been identified by astronomers from the Center for Astrophysics | Harvard and Smithsonian as the first confirmed object to complete one orbit around the sun for every ten orbits made by Neptune. This discovery adds a new chapter to the understanding of orbital resonances in the outer solar system.

The trans-Neptunian object (TNO) was discovered through the Large inclination Distant Objects (LiDO) survey, which uses the Canada-France-Hawaii Telescope for primary detection and Gemini Observatory and Magellan Baade for further observations. The survey seeks out distant bodies on steeply inclined orbits, often overlooked in traditional surveys focused on flatter orbital paths.

"This is a big step in understanding the outer solar system," said Rosemary Pike, the lead researcher. "It shows that even very distant regions influenced by Neptune can contain objects, and it gives us new clues about how the solar system evolved."

Unlike other resonant TNOs that tend to approach the sun when Neptune is at a distance, 2020 VN40's orbit brings it closest to the sun precisely when Neptune appears nearby-though the two are not physically close due to 2020 VN40's steep orbital tilt. From a top-down perspective of the solar system, they align visually, an orbital behavior unseen in other known 10:1 resonators.

"This new motion is like finding a hidden rhythm in a song we thought we knew," said co-author Ruth Murray-Clay of the University of California Santa Cruz. "It could change how we think about the way distant objects move."

Dr. Samantha Lawler, a core member of the LiDO team from the University of Regina, added, "It has been fascinating to learn how many small bodies in the solar system exist on these very large, very tilted orbits." 2020 VN40's average distance from the sun is about 140 times greater than Earth's.

The object's unusual dynamics support theories that Neptune temporarily captures distant objects into resonant orbits. This phenomenon may have played a key role in shaping the distant solar system.

"This is just the beginning," said Kathryn Volk of the Planetary Science Institute. "We're opening a new window into the solar system's past."

Research Report:LiDO: Discovery of a 10:1 Resonator with a Novel Libration State