This episode is presented by eBay.

Rob, everyone loves a deal and a bargain from time to time, don't they? Absolutely, mate. And you know where you can grab a great deal? Talk to me. Where? The eBay app. Yes, you are correct. You didn't need to talk to me. I already knew it. I love eBay. When you're buying, you can discover loads of hidden gems. there's so many items where you think I would have never found that anywhere else.

Then when you're buying, you can discover loads of hidden gems. There's so many items where you think I would have never found that anywhere else. Then when you're selling, it's so simple and most

importantly, free. It's free, Rob. When it's this easy to sell for free and there's great deals

on things you love. You can't help but say when it's eBay. It excludes vehicles and business

sellers. Welcome to Science Talk, the

weekly podcast of Scientific American for the seven days starting August 20th, 2008. I'm Steve

Murski. Buzz Aldrin is an American icon. The West Point graduate piloted the lunar module

on Apollo 11 and became the second human being to walk on the moon.

He was in New York City to promote the new animated movie Fly Me to the Moon, in which he plays himself.

We talked about an article he wrote for the March 2000 issue of Scientific American called A Bus Between the Planets, about how gravity-assist

trajectories between Earth and Mars could greatly reduce the cost of getting people and equipment

between the planets.

We also talk about the Constellation Program, which will replace the space shuttle, and is

supposed to return us to the moon by 2020.

We spoke in the lobby of the Gramercy

Hotel in Manhattan. That's why you hear music in the background. Before I even had a chance to

ask him a question, he started to talk about solar power articles he'd seen in Scientific

American. You've had some things recently on terrestrial solar power.

Oh, yes, absolutely.

And I've been in touch with some of the people who've represented that.

And I think, though I'm not sure that whether there has appeared there a review of a recent study on space-based solar.

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