Do you think space exploration is important? Is it worth the billions our governments spend?
Yes and no. I do think that we should know something about our universe or at the very least our solar system. Doing so lets us learn more about Earth (its history and prospective future). It also leads us to important scientific discoveries, such as the theory of relativity, a better understand of how gravity works, and quantum mechanics. I recently took a cosmology class and greatly enjoyed it, so I'm not against learning about our universe. I do think, however, that the amount of money spent and the way in which it is spent is in need of reform.
I do not think we should be spending so much money exploring the moon and Mars so that we may colonize them or find other life forms on them. The exploration and research of these places should instead be geared towards better understanding Earth, the solar system, the galaxy, and the universe in general.
As for how much money is spent on space exploration, I frankly find it appalling. NOAA (National Oceanic and Atmospheric Administration) gets a fourth (I belive; it's on an episode of Colbert Report which I do not have the time to look up right now) as much money as is given to NASA. Are not researching how the weather on our own planet works and what lies beneath us in our own seas more important than looking for alien life forms or another planet to inhabit? We know less about our own oceans than we do about the universe, and we still can't predict day to day weather. Is this not disgusting? Spending more time, money, and effort on exploring space than on our own planet personifies humanity's constant inability to be happy with what we have.