When I did my spacewalks, it was during space station construction. So the shuttle was docked to the fledgling ISS at the time. So we would always stay tethered.
After the loss of Columbia a couple of years ago, I think we were reminded of the risk. All of us, though, have always known that the Space Shuttle is a very risky vehicle, much more risky than even flying airplanes in combat.
You can't 'control' a Mars mission from Earth. The Mars mission is going to have to be controlled by the people on Mars... There is just too much involved that is out of sight of Earth.
Spacemen die if they stay in one place.
The whole Hubble program has just been a fabulous testament to the NASA science community and the NASA astronaut community.
Things felt pretty crazy on earth in 1969, but the cosmos was friendly. Astronauts had round-trip tickets; they got home.
Land on Mars, a round-trip ticket - half a million dollars. It can be done.
When you think about exploring deep space, it's very dangerous for humans. To potentially sacrifice human life is a delicate proposition. On the flip side, if you want to send a robot to another planet for an extended period of time and at some point you know it'll cease to function, it's not considered a tragedy.
Spaceflight will never tolerate carelessness, incapacity, and neglect.
You can be an astronaut, knowing it can be super dangerous but understand intuitively what the risk issues are. Not having the same usable knowledge about the risk of football, or any line of work, doesn't work.
Astronauts have been stuck in low-Earth orbit, boldly going nowhere. American attempts to kick-start a new phase of lunar exploration have stalled amid the realisation that NASA's budget is too small for the job.
No, I think most astronauts recognize that the space shuttle program is very high-risk, and are prepared for accidents.
It's very dangerous to put astronauts on a moon base where there's radiation, solar flares and micro meteorites. It'd be much better to put robots on the moon and have them mentally connected to astronauts on the Earth.
We'll go back to the moon by not learning anything new.
One of the major problems with long-term deep space human flight is the requirement for radiation shielding.
Just to continue a space program because it's a space program? No, I don't think we have an obligation for that.
Space travel is the only technology that is more dangerous and more expensive now than it was in its first year. Fifty years after Yuri Gagarin, the space shuttle ended up being more dangerous and more expensive to fly than those first throwaway rockets, even though large portions of it were reusable. It's absurd.
Flying in space is risky. It will never be safe, and the best thing we can do is manage those risks. It's important for people, for human beings, to be in space because they're adaptable and because they're not pre-programmed software that can go off and do tasks that are appropriate for machines.
If you're in space on the way to Mars, and a conflict develops... you can't turn around and go back, because Earth is already gone on its orbit.
During my 8 years as chairman, I had the privilege to peer into the future to see dynamic citizen astronauts returning to and from the heavens which we can expect in the future.
I think even in bad times it's good to keep some money going into research. And that's the purpose of the whole space program. It's not just exploration and going to see how far we can go out into space and keep people alive and bring them back, although exploration certainly has its place.
The earth appears fragile and defenceless in the harsh environment of space and when one sees the amount of technology required to keep a human alive in that environment, one begins to feel blessed that one is an inhabitant of planet earth that supports human life.
The first two missions have some test objectives, some new capabilities that we're going to try to develop on orbit to possibly be used on later flights.
The NASA humans-to-Mars program is all sizzle and no steak.
My view is that we should go back to the moon, build up the infrastructure to make flights there commonplace - be comfortable with it - then use that infrastructure to expand and go to Mars.
