How was it proved that gravitation was a function of mass? [more inside]
posted by Lorc on Jul 6, 2009 - 10 answers

Gravity/Life/SocietyFilter: So the Earth is all lumpy, with more or less gravity in some places. Has anyone ever corroborated it with life/social/world things? Many questions inside... [more inside]
posted by amberglow on Feb 18, 2006 - 33 answers

Science hour question: My niece asked me this and I didn't have a good answer. People in orbit around the earth are "weightless." But what would happen if an object in space were kept stationary at 150-200 miles up? Would an astronaut in such a stationary but very high station in fact feel significant gravity? Is "weightlessness" (in near-Earth space) an artifact of a free-fall orbit? C'mon rocket scientists, I know you're out there.
posted by socratic on Dec 12, 2004 - 20 answers

ScientificIlliterateFilter: If the sun's gravity is so strong as to keep whole planets circling it in orbit (even ones million of miles away), how come light and heat (incredibly fragile things compared to planets) can escape as rays (or whatever they are)?
posted by amberglow on Nov 14, 2004 - 53 answers