Help me think of a space-themed gift for an awesome 35-year-old guy. [more inside]
What were the best photos we had of the planets in our solar system before the Pioneer and Voyager missions? [more inside]
Is there a distance at which a satellite will orbit a body indefinitely? Is this distance a universal constant? [more inside]
Planetary magnetic fields and life: Is there any reason to believe that strong magnetic fields on rocky inner planets are relatively uncommon? [more inside]
Why hasn't anyone invented cheap space probes? Some kind of thing that could be sent up en mass to gather just base data we don't have on all the planets/moons/etc . . .? [more inside]
I want to buy my son, who is turning six, a telescope for his birthday. I don't want to spend a fortune, but one site I looked at for advice said anything less than $300 is a piece of junk. Anyone have any advice (including specific models) on one I can by this budding astronomer for $100 or less?