Martian Astronomer Filter--when Mars moves like this in the sky from our point of view on Earth, how does the Earth appear to move from Mars' perspective? [more inside]
posted by JMB1138 on Feb 24, 2011 - 3 answers

Is there a distance at which a satellite will orbit a body indefinitely? Is this distance a universal constant? [more inside]
posted by doublehappy on Oct 16, 2009 - 28 answers

AstroPhysics: Why doesn't the moon move towards the earth, and other satellite related questions. [more inside]
posted by dpx.mfx on Aug 21, 2006 - 22 answers

Hypothetical from Moon-orbit to Earth-orbit question. I already know about free return trajectories, but what if something went wrong and your ship (currently orbiting the moon) didn't leave lunar orbit at the point it was supposed to? What might happen? [more inside]
posted by np312 on Aug 17, 2006 - 8 answers