Tragedy, of course, is not unknown to space exploration. Between Challenger, Columbia, Soyuz 1, and Soyuz 11, 18 astronauts have been killed on missions. Eleven more have died during training. Ground workers have also given their lives, including 48 who were killed during a single rocket fueling gone wrong. And then there's the long, harrowing list of close calls where we narrowly avoided disaster.
Now, I don't mention that to scare anyone into thinking that space travel isn't worth the risk, but to explain why we take the risks. When I sat on the launchpad, I knew there was about a 1 in 38 chance that I was about to be killed. Those are decent odds at the casino, but not the greatest when you're strapped to one of the most complicated machines ever built about to rip free from the bonds of Earth. I had no proof that the men and women responsible for my safety didn't rush through the job so they could cut out early for lunch, but because I trusted them, I knew that wasn't the case.
That's why I didn't panic when I went blind. It wasn't just because I have a long history of facing down dangerous situations like a mustachioed John McClane (although I do), but because I knew that no matter what happened, my crew and I would do the best we possibly could to deal with it. You'd be surprised by what sort of risks you're willing to take when you have knowledge, experience, and trust at your back.