What do you think of NASA's efforts to develop new technologies for getting humans in and out of space?
NASA does R&D in a lot of subjects. For example, the agency spent a lot of money on the X-33 program, which was for a craft that would take off horizontally like a plane and get into orbit. But that project was set aside. The return capsule being developed for the Orion module [the shuttle's replacement scheduled for 2014] is probably the right stage to use at this point. But space tourists in a future inflatable hotel shouldn't have to use a capsule. We need to have redundancy options [for getting people back and forth into space], and these are not being worked on at this time.
A craft that takes off and lands like an airplane would also be highly marketable to India and China and would increase [the U.S.'s] prestige. What we need is a way to deliver people and to do what we originally committed to do, which is have an emergency return vehicle at the International Space Station, rather than relying on the supposed cost effectiveness of a [Russian-made] Soyuz ship. If that's the only way we can get to the $100-billion space station after 2010 [when the space shuttle is retired], that is rather unfortunate. So it may make sense to extend the shuttle for a few more years. There are other ways of filling a gap [in craft availability and mission objectives] rather than squeezing it at both ends. That's what NASA did with the Gemini program between the Mercury and Apollo programs in the 1960s.
What do you think about fellow astronaut Edgar Mitchell's claims that the government is covering up the existence of aliens?
Well, despite the ridicule of other people, some people maintain that improbable things exist. Someone wanted to proclaim that when we landed on the moon that we would sink 50 feet [15 meters] into the lunar dust. That would have been a Nobel Prize–winning statement if it had turned out to be true; this now-unknown person could have been the famous predictor of the Apollo disaster. But for now, Edgar has carved out a future for himself and he's got to live in it.