They all knew the mothership was coming, they all knew it was a flying saucer, they all knew it came from another planet through the vacuum of space. And so what do they do, to the left of that monument? They set up runway lights. And I'm thinking, if you could travel through the vacuum of space, you don't need runway lights. Runway lights are if you're using air for lift. Aliens would not need air for lift.

If cosmological theory were dominated by women, who are no strangers to cycles, how can we know for sure that we wouldn't then be told that the oscillating universe is the more aesthetically fulfilling alternative?

I don't require that the main guest [of StarTalk] have any science knowledge or background at all. It's just, I have a conversation with them, it's long and winding, and we find out what parts of what we learn about the person lend themselves to further scientific discussion with an expert who is brought into the studio. So that's how that comes together.

We only went to the moon for military reasons. The space enthusiasts of the day kept saying, "Oh, we're on the moon; we should be on Mars in ten years." That's if it was driven by exploration, but it's never been driven by exploration.

When we see animals doing remarkable things, how do we know if we're simply seeing tricks or signs of real intelligence? Are talented animals just obeying commands, or do they have some kind of deeper understanding? One of the biggest challenges for animal researchers is to come up with tests that can distinguish between the two.

The first colony on Mars is not going to be built by a private company. How are you going to make money? You're not.

We should not be ashamed of not having answers to all questions yet... I'm perfectly happy staring somebody in the face saying, 'I don't know yet, and we've got top people working on it.' The moment you feel compelled to provide an answer, then you're doing the same thing that the religious community does: providing answers to every possible question.