I was somewhat surprised that the simulation would lead to precession, though. I would have expected the orbit to wobble, but it the type of error introduced in these simulations tend to always go the same way...
Perfect A.T. Thank you! That is what I thought, but running a simulation I wrote, there appeared to be precession. I thought that it was an artifact, but wanted to be sure.
If we had a literal two body system (point masses M and m), with one orbiting the other according to Newton's Law of gravitation, would there be orbital precession? Or would they map out the same ellipse each time?