Scientists discover a stable object moving with Uranus, call it its ‘girlfriend’

In a research paper titled ‘A Minor Planet in an Outer Resonance with Uranus,’ scientists led by Daniel Bamberger from Norholt Branch Observatories, K Ly from the University of California, LA, Sam Deen from Deep Random Survey, and Elvis Oliveira Mendis from Instituto de Física, Brazil, have discovered a rare and stable object moving in sync with Uranus, which they reportedly call its ‘girlfriend’.

The team found that the centaur 2015 OU194 is in a special orbital pattern, known as a 3:4 resonance with Uranus, meaning it completes three orbits around the Sun for every four orbits completed by Uranus. 

This pattern is remarkably stable and has remained intact for at least one million years in the past and is expected to continue for another 500,000 years into the future.

The space object 2015 OU194 was officially announced on May 14, 2025, with additional details released on June 27, 2025.

It was first observed on July 12, 2015, using the Subaru Telescope in Hawaii, with the last observation within that year-long window taken on July 12, 2016. Later, scientists discovered more archived images of the object from September 16, 2017, and December 7, 2018, which helped refine its path.

In total, scientists now have 34 observations of this object, which they have submitted to the Minor Planet Center, the official body responsible for tracking such celestial objects. Using this data and specialised software, they calculated its precise orbit.

Key facts about 2015 OU194:

It is 23.3 times farther from the Sun than Earth on average.

It takes approximately 113 years to complete one orbit around the Sun.

Interestingly, no previous reports have documented any other objects in this exact orbital pattern between Uranus and Neptune.

While searching for other objects with similar orbital behavior, scientists identified:

2013 RG98, which also follows this pattern for hundreds of thousands of years around the present time.

2014 NX65, which is influenced more by Neptune’s gravity.

This discovery highlights a rare and stable dance between Uranus and small objects in the outer Solar System, providing valuable insights into how distant celestial objects move far from the Sun.