Earlier today, the space shuttle Columbia broke up over Texas. Obviously, this is tragic, especially being so soon after the anniversary of the Challenger disaster.

On other forums, people have commented on how the shuttle was a glorified waste of money. The scientist in me doesn't disagree. I'm sure we could be more efficient and accomplish more science with unmanned probes. But I think that in some respects that's not really ever been the point of space exploration.

Probably everybody has wondered at some point in their childhood what it would be like to travel to the stars; every kid in the last forty years has dreamt of being an astronaut at some point. Most of us never achieve that goal. But some people never give up, they follow their dreams and become the select few who can call themselves astronauts. And that's the biggest tragedy about today's accident; the seven crew members who were lost today represent the distilled dreams of humanity. We need manned space exploration because we need to dream of the future, to explore the unknown and to reach beyond the confines of our world.

Could we accomplish more science with less money, and at less risk? Undoubtedly. But at what price? How do you value the dreams of humanity? I hope that this isn't the beginning of the end for the space program.