To give some insight, I'm creating a simulation, with gravity, planets, forces... And I would like to increase performance, by not doing unnecessary calculations. I could know what calculations, to not perform, if I know whether a planet, body or star is revolving an other body and no the other way around.
I don't know if this is even possible, because both bodies creates attraction forces between them, but:
Imagine a Two-body problem, a body with more mass than the other is located at the center of a reference system, and it has a moon orbiting. How I can, mathematically, know which body is orbiting the other and not the other way around? And if the both have similar masses, is this even possible? If this is not possible let me know I'm wrong.