Changing apoapsis/periapsis without burning at periapsis/apoapsis? I'm currently trying to circularize a probe's orbit, but I can't really wait until I get to periapsis or apoapsis, because I need to keep this probe at a specific distance from a second one (also in circular orbit). Is there a good way to change the apsides from any point on an orbit? (Also the difference between them is small at the moment, only 250 meters)