Strongest Attractor

The Strongest Attractor of an object is the object in the simulation that has the strongest gravitational effect on the first object. This is a read-only property, as Universe Sandbox automatically calculates an object's Strongest Attractor based on the forces of gravity acting on the object. If the object is the only one in the simulation, it has no Strongest Attractor.

Location
The Strongest Attractor property is located in the Impacting Objects section of the Motion tab of an object's properties panel.