2D Space Game. Locked Orbit

Hello! I making a 2D space sandbox game where I controll a planet and cruise around. I have made a "gravity" by using a circle collider ( with "is triggerd" and "used by effector" checked in) and a point effector 2D with minus "Force Magnitude" value. But I want other objects when they come near enough to be locked in a orbit. What I mean by a locked orbit is that they orbit around at the same speed and always have the same distance to the player planet.

Im thinking about using another circle collider to trigger the locked orbit but I no idea how to make the locked orbit.