A New Dance Partner for Uranus: Discovering a Minor Planet in Outer Resonance

Daniel Bamberger and colleagues discovered that minor planet 2015 OU194 is in a rare, stable 3:4 outer mean motion resonance with Uranus, the first known example. Using extended observations and simulations, they showed its orbit remains resonant for over a million years. Two other candidates were examined, but none matched 2015 OU194’s stability and near-circular orbit.