If I looked up at the sky some time at night, pointed to the moon and gave you the exact orientation of my arm (the two angles in the north/south and east/west directions) and told you the exact time of night and date it was, would you be able to tell my exact location in the world? If so, how?
posted on May 30, 2007 - 39 answers

What would be the effects on the earth if the moon exploded? [more inside]
posted on Aug 28, 2006 - 29 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 on Aug 17, 2006 - 8 answers