Thought you meant just automatically.
In that case, the simplest way is a set of actions. You'll want to set your angle via your controls. Then, every tick, set your player to the planet's x and y, and then use the move forward at angle action together to place it in the right place. The distance is how high you want your orbit, and the angle would be angle(planet.x,planet.y,touch.x,touch.y) (or mouse.x and y if you're using mouse). If you're using keyboard arrows, you'll want an angle variable that gets modified by your arrow keys.
So basically I'm just setting the angle of the planets X and Y coordinate?