Why do we go to space?

We all know that space flight is ludicrously expensive, so why do we do it? As unlikely as it might sound, spaceflight could very well be essential to our continued survival as a species. This planet won't last forever, after all.

Genesis space probe

NASA alone has sent up hundreds of scientific space probes and manned shuttle missions over the years. Skeptics of the validity of such space programs invariably point out the lack of any significant instantaneous benefit to society as a whole, but this idea is incredibly short sighted. The main argument that is usually made in defense of space exploration is one of pathos. I agree that it isn't necessarily the most useful argument objectively, but it works. Ever since man first looked up at the sky he has dreamt of touching the stars. It is that ever present urge to explore and to look around the corner, to truly know what's out there. This is an admirable trait of humanity, a trait that has managed to guide us to what we have become today. Curiosity is what makes man great. 

Space exploration is the very symbol of human ingenuity. We evolved on this planet, we have no biological means to leave this tiny little ball, but through our intellect we have managed to touch other worlds. How can an argument like this not pull on your heart strings, at least a little?

Nebulae like this are some of the most beautiful things in the universe

I often find that an argument from logic is more effective. It is foolish to say that there is no reason to develop space technologies or to travel to space, we'll have to eventually. Earth cannot sustain us forever, it has limited resources and we've already begun to destroy it with pollution and general poor care. It will eventually become necessary to look beyond our planet to find the necessities for a modern society, but how can we do that if we haven't developed the technology? We've already seen that it takes a long time to advance in space, it's been 53 years since the NASA space shuttle program started, and look how far we've gotten. If we decide to just worry about earthly problems, we will be entirely unprepared when we finally do have to leave our little rock. That's another problem with the argument against going into space. Sure it sounds good to say "lets focus on more pressing issues" but the problem is that we will never run out of "pressing issues". Society is just one crisis after another, if we don't find time to dream about the universe beyond our planet during the multitudes of everyday crises, then we'll be doomed to stay on this planet until it can no longer sustain us.

In the end, it's all about thinking of the future. Yes, it may be hard for the average person to see the daily benefit of a space program, but it's not the daily benefit that ultimately matters. If we give up on space, then we give up on our dreams, and our hope.