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Astronomy Cast, episode 199 from Monday, September 20, 2010.

The Voyager Program.

Welcome to Astronomy Cast, our weekly facts based journey through the cosmos, where we 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, and with me is Dr. Pamela Gaea, professor at Southern Illinois University.

Hi Pamela, how are you doing?

I'm doing well, how are you doing Fraser?

Great, 199. That's really close to 200.

Yes, yes it is.

I know a lot of people want to do something special for 200.

I don't know, no, I have to think of something.

Yeah.

Either that or you can just like, you know, explain how to do gravitational mathematics.

Everyone get a piece of pen and paper out, alright?

No, there are some things I like myself too much to do, and explaining tensor calculus falls into that category.

Yeah, over the radio.

Over the radio, yes.

Alright, so launched in 1977, the Twin Voyager spacecraft were sent to explore the outer planets, Jupiter, Saturn, Uranus and Neptune.

Because of a unique alignment of the planets, Voyager 2 was the first spacecraft to ever make a close approach to Uranus and Neptune.

Let's take a look back at this amazing program and see where the spacecraft are today.

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