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Astronomy Cast Episode 210 from Monday, December 6, 2010.

The Mars Exploration Rovers, Spirit and Opportunity

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 Universe Today, and with me is Dr. Pamela Gay, a professor at Southern Illinois University, Evertsfield.

Pamela, how are you doing?

I'm doing well, it's snowing here.

Yeah, and we are having the most horrible rainstorm ever.

Flood warnings.

That's not good.

Yeah, I am really sick of the wonders here at the West Coast, I gotta say.

Anyway, but let's think of another more hostile environment.

Yeah, so the Twin Mars Exploration Rovers, Spirit and Opportunity have been crawling around the surface of Mars since early 2004, years longer than they were expected to live.

And what they have discovered there on Mars has given scientists their best understanding of Martian geology over the last few billion years.

Let's investigate these amazing rovers and their ongoing mission.

You know, when we started Astronomy Cast, we were amazed at how long the Martian rovers had been going, you know, it's amazing.

It's been years and years.

That was 2006.

Now we're in 2010, almost into 2011, amazed by how long the Spirit and the Opportunity have been going for.

Well, we might have actually lost Spirit.

Yeah.

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