There is a theorem that colloquially translates, You cannot comb the hair on a bowling ball. ... Clearly, none of these mathematicians had Afros, because to comb an Afro is to pick it straight away from the scalp. If bowling balls had Afros, then yes, they could be combed without violation of mathematical theorems.
Neil deGrasse TysonThis fear factor, this war driver is a very strong one and it's been with the species ever since the beginning and it motivated the Great Wall of China. War can be aggressive or defensive, right? So it motivated the Great Wall of China. Our space program was reactive to Russia.
Neil deGrasse TysonTo view space as, "Well, let's go to Mars now," or "Let's do this now," maybe we should rethink of space as our backyard and have a suite of launch vehicles that can enable any ambition a person has regarding space. It's the same way you can go to buy a car: I want to go offroading, I'll buy this model. I'm a city driver, that's this model. I want to use less fuel, well, that's this model. They're not selling you one car, you have options. So when I think of space, I think of having options.
Neil deGrasse TysonAny astrophysicist does not feel small looking up at the universe; we feel large.
Neil deGrasse Tyson