This 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.

Ignorance is a virus. Once it starts spreading it can only be cured by reason. For the sake of humanity, we must be that cure.

If we have the power to turn another planet into Earth, then we have the power to turn Earth back into Earth.

All tweets are tasty. Any tweet anybody writes is tasty. So, I try to have each tweet not simply be informative, but have some outlook, some perspective that you might not otherwise had.

The urge to miniaturize electronics did not exist before the space program. I mean our grandparents had radios that was furniture in the living room. Nobody at the time was saying, 'Gee, I want to carry that in my pocket.' Which is a non-thought.

Scientific inquiry shouldn't stop just because a reasonable explanation has apparently been found.

For all we know, the aliens have already done this and unwittingly concluded that there was no intelligent life on Earth. They would now be looking elsewhere. A more humbling possibility would be if aliens had become aware of the technologically proficient species that now inhabits Earth, yet they had drawn the same conclusion.