It takes a few years to prepare for a space mission. It takes a couple of years just to get the background and knowledge that you need before you can go into detailed training for your mission. So most astronauts are astronauts for a couple of years before they are assigned to a flight. Once you are assigned to a flight, the whole crew is assigned at the same time, and then that crew trains together for a whole year to prepare for that flight.

It is true that we were cautious in our planning. There were many uncertainties about how well our Lunar module systems and our Pressure suit and backpack would match the engineering predictions in the hostile lunar environment. We were operating in a near perfect vacuum with the temperature well above 200 degrees Fahrenheit with the local gravity only one sixth that of Earth. That combination cannot be duplicated here on Earth, but we tried as best we could to test our equipment for those conditions. For example, because normal air conditioning is inadequate for lunar conditions, we were required to use cold water to cool the interior of our suits. We did not have any data to tell us how long the small water tank in our backpacks would suffice. NASA officials limited our surface working time to 2 and 3/4 hours on that first surface exploration to assure that we would not expire of hyperthermia.

Always before, people ready to enter space have been civilized in a way you humans have avoided altogether. We fear if the people of Earth are allowed into space in their uncivilized state, the results could be disastrous beyond anything you imagine. At the moment, we are considering a permanent quarantine on Earth. We don't mind you exploring your own solar system; there's not much there anyway. But we cannot allow you to carry this sickness, whatever it is, into the galaxy at large.

When stuck in outer space, moonwalk home. I can dance as well as any hitchhiker in the galaxy, and you can 42 off if you don’t believe me.

An ironic death for someone with a leaky space suit: too much oxygen.

If a Martian (who, we’ll imagine, never dies except by accident) came to Earth and saw this peculiar race of creatures — these humans who live about seventy or eighty years, knowing that death is going to come — it would look to him like a terrible problem of psychology to live under those circumstances, knowing that life is only temporary. Well, we humans somehow figure out how to live despite this problem: we laugh, we joke, we live.

Space is dangerous. It's what we do here. If you want to play it safe all the time, go join an insurance company.

It's like if you're an astronaut and you've been to the moon, what do you want to do with the rest of your life?

If a Martian (who, we'll imagine, never dies except by accident) came to Earth and saw this peculiar race of creatures - these humans who live about seventy or eighty years, knowing that death is going to come - it would look to him like a terrible problem of psychology to live under those circumstances, knowing that life is only temporary. Well, we humans somehow figure out how to live despite this problem: we laugh, we joke, we live.

That’s right. Five minutes into the all-hands meeting, the fundamental values of this totalitarian society had received the support of the vast majority of the crew. So, let me tell you, when humans are lost in space, it takes only five minutes to reach totalitarianism.

If we had a starship, we could move near a black hole, stay there for a half hour and then come out. Outside hundreds of years could have gone. So we could... come away from the black hole into the far future easily.

When you're getting ready to launch into space, you're sitting on a big explosion waiting to happen. So most astronauts getting ready to lift off are excited and very anxious and worried about that explosion — because if something goes wrong in the first seconds of launch, there's not very much you can do.

I give you three examples: first, medical space research may open up new understanding of man's relation to his environment. Examinations of the astronaut's physical, and mental, and emotional reactions can teach us more about the differences between normal and abnormal, about the causes and effects of disorientation, about changes in metabolism which could result in extending the life span. When you study the effects on our astronauts of exhaust gases which can contaminate their environment, and you seek ways to alter these gases so as to reduce their toxicity, you are working on problems similar to those in our great urban centers which themselves are being corrupted by gases and which must be clear.

I don't think the human race will survive the next thousand years, unless we spread into space. There are too many accidents that can befall life on a single planet. But I'm an optimist. We will reach out to the stars.