There are countless space activities that would be no less exciting than the moon missions were, I have no doubt. The search for life on Mars, for example.

I like seeing how people have succeeded when others would have presumed they would have failed, and others just go along with whatever everyone else does.

I wonder if, in fact, we have been observed by aliens and upon close examination of human conduct and human behavior they have concluded that there is no sign of intelligent life on Earth.

If there were biologists among the extremophiles organisms that live in extreme conditions, they would surely classify themselves as normal and any life that thrived in room temperature as an extremophile.

You can deceive yourself into thinking that America is a technological leader, but if you don't see what anyone else is doing you have no accurate assessment - you can't make an accurate assessment of where you fit and why. I consider our moving frontier in space as the anecdote to that downward trend.

If you love what you do, you'll be your best at it compared to anything else you might have chosen as a career. Or at least you will love it more, and you won't lead a depressed day of your life.

The greatest explorer of recent decades is not even human.