There are no wild, seedless watermelons. There's no wild cows... You list all the fruit, and all the vegetables, and ask yourself, is there a wild counterpart to this? If there is, it's not as large, it's not as sweet, it's not as juicy, and it has way more seeds in it. We have systematically genetically modified all the foods, the vegetables and animals that we have eaten ever since we cultivated them. It's called artificial selection.
Neil deGrasse TysonWith no gravitational force to work against, your body not only doesn't need the same amount of muscle and bone, it starts breaking them down. As on Earth, so in space: use it or lose it. And exercise may not solve the problem.
Neil deGrasse TysonPhysics is the only profession in which prophecy is not only accurate but routine.
Neil deGrasse TysonThe problem, often not discovered until late in life, is that when you look for things like love, meaning, motivation, it implies they are sitting behind a tree or under a rock. The most successful people recognize, that in life they create their own love, they manufacture their own meaning, they generate their own motivation. For me, I am driven by two main philosophies, know more today about the world than I knew yesterday. And along the way, lessen the suffering of others. You'd be surprised how far that gets you.
Neil deGrasse Tyson