We found Associate Astronomer Tom Fleming, who organized the lecture “”Beyond UFOs: The Search for Extraterrestrial Life and Its Astonishing Implications for Our Future”” at the Steward Observatory.

Wildcat: You’re on the spot. First of all, what is a planet?

Fleming: There was just a big debate two or three years ago about what a planet is, and Pluto didn’t make the cut. We consider a planet anything that has enough mass to be spherical, it orbits a star, and it sort of has cleared the path of all other competing bodies in its orbit.

W: So it’s like an interplanetary wrestling match or something? How do they do that?

F: Well, gravity. Earth, Venus and Mercury are very low mass, so they don’t have as much mass as Jupiter.

W: They need to work out.

F: Yeah. They have to have more mass to be heavier.

W: Is it hard to orbit the sun?

F: No, it’s not hard. Gravity does it all. All of these planets were formed in a disk of material that existed after the sun and all of the bits of ice and rock came together and coalesced under gravity to form the planets. Some of them are more massive than others.

W: So if there are aliens in this solar system, what would they look like?

F: We’re pretty sure there aren’t aliens like us, meaning humanoid life forms.

W: Is it ’cause they’re hiding?

F: We think that it’s possible that there could be life, but it might be microbial life. Like germs and bugs.

W: Eww.

F: There could be fish, for example, on Europa, which is one of the moons of Jupiter. We believe that the inner part of Europa is molten water, so you’ve got a water ocean. You’ve got ice in a surface, and underneath there’s water and fish.

W: But wouldn’t they be fish sticks already, because it’s so hot?

F: They could survive. I don’t think it would be as hot. It would boil, but it could be the same temperature as any of the oceans.

W: So like sushi.

F: Like sushi, on Europa.

W: That would be expensive! So the quote from Arthur C. Clarke about magic…

F:””Very advanced technology is indistinguishable from magic.”” It’s like, imagine someone from the age of, say, the ancient Greeks, or even someone from pre-historic times, coming to Earth today. Seeing that device (the recorder) or our iPods, or television. They would think it’s magic.

W: So aliens don’t use magic?

F: No. To us, it would seem like magic.

W: I saw that diagram that had the different kinds of life. What are flagellates?

F: You know, I don’t know. I’m not a biologist, I’m an astronomer.

W: Yeah, I was just confused. Flatulence?

F: That confused me too.

W: Yeah, I’m always confused by it.

– interview by Andi Berlin