What does it take to become an astronaut?S

NASA recently began accepting applications for its 21st class of astronauts, and while you can certainly read about what it takes to become one on NASA's website, there's something about hearing it from someone who's actually been through the whole process of becoming an astronaut, and later training as one, that an Astronaut Selection and Training brochure just can't match.

With this in mind, BoingBoing's Maggie Koerth-Baker sat down to talk with astronaut Rex Walheim about some of the finer points of being a NASA spaceflyer. Below is just one of her questions (she asked five reader-submitted questions in total), but the whole thing is really worth the read. Head over to BoingBoing to check it out.

Maggie Koerth-Baker: This question comes from reader kansas: When you're going through the selection process, hoping beyond hope to be chosen to train as an astronaut, would you admit to being afraid of anything, or would than seem not very astronaut-like? Is there a place in the training for people to admit to having fear?

Rex Walheim: I think it would depend on how you talk about something like that. If you say, "I'm scared to death," you might not make it. But you can say, "I'm concerned about my safety." Frankly, if you're not concerned about sitting on 10 stories of high explosives, you're not thinking hard enough. The funny thing is, after 5 years of training, it actually doesn't cross your mind too much.

I remember my first flight. You're so excited. You've been wondering, is it ever going to really happen. You never know whether launch day will actually be launch day. I remember that I felt the engine start and the rocket boosters start, and I thought, "I really get to do this today! Nobody can stop me now!" That was an incredible adrenaline rush. On simulations we have things breaking and going wrong to test us. But on the real day nothing went wrong. I had the chance to look around and think, "Oh, this is kind of dangerous." But 8.5 minutes later we were at 17,000 mph and in orbit. You're so trained to do the job, you just kind of put the danger aside. The harder time is leading up to the mission, when you're with your family and thinking about what could happen several weeks and months ahead.

Image of Spacewalk via NASA Astronaut Selection and Training Fact Sheet