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I'm good, I'm recording again.

Astronomycast, episode 201 from Monday, October 4, 2010.

Tight.

Welcome to Astronomycast, our weekly facts based journey through the cosmos, where you help you understand not only what we know, but how we know what we know.

My name is Fraser Cain, I'm the publisher of University Day, and with me is Dr. Pamela Gay at Professor at Southern Illinois University, Everto.

Hi Pamela, how are you doing?

I'm doing well, a little bit of hay fever here, how are you surviving up there?

Oh, it's great, we're having like a second summer, it's just roasting here, it's great, I love it.

Okay, so no don't you chat today, we just got Titan.

Titan is Saturn's largest moon, and the second largest moon in the solar system, it's unique as the only moon with an atmosphere.

In fact, scientists think that Titan's thick atmosphere, rich in hydrocarbons, is similar to the early Earth and could give us clues about how life got started on our own planet.

Titan.

All right, well let's go right back to the beginning, little history lesson, we didn't always know about Titan, I guess humans always knew about Saturn,

but they didn't know that it had a gigantic atmosphere moon.

No, no they didn't, and in fact, Saturn was the second planet after Jupiter, I guess third, if you count Earth, that had moons found orbiting it.

And it was in 1655 that Christian Huygens, for whom the Huygens probe was named after.

Right, because Galileo looked at Saturn, he discovered the Galilean moons around Jupiter, he discovered the ears of Saturn, but I guess he missed the moon.

He did indeed miss the moon, so we had to wait a few decades until 1655, and then Christian Huygens, he started finding moons popping up around Saturn.

So back then they started out numbered, it took a good long time before they started figuring out how to name these suckers, but initially Titan was the fourth in it, stayed as Saturn for quite a number of years.

And sometimes in research journals, I've seen, yeah, it'll refer to Titan as just Saturn for.

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