Naked pioneers you to the

final frontier. I'm Matt Kaplan. Pioneer 10 was the first human-built envoy to

Jupiter and the first to pass out of our solar system. We'll talk with the author of a

new book about the plucky probe and its sister ships, and of course

about those revealing plaques they are delivering to ET.

Something tells me what's up is happening at the zoo where Bruce Betts will offer up a new space trivia contest

and Emily will provide a breath of fresh though thin Martian air right after these headlines.

IBM has announced something called the World Community Grid.

The effort is intended to use millions of personal computers to provide a gigantic distributed

computing platform for scientific projects.

If this sounds familiar to you SETI at home participants, it's for good reason.

The Search for Extraterrestrial Intelligence Project paved the way for this new effort,

virtually inventing grid computing. We'll have more on this story next week.

The new Spitzer Space Telescope orbiting the Earth is returning data that may help distant Pluto keep its status as a planet.

Other recently discovered objects that are even farther from the Sun seem to be somewhat smaller than first thought.

And NASA has just concluded an international workshop.

The Washington session considered opportunities and possible collaborations in missions that are part of the U.S. Vision for Space Exploration.

You can read much more about these and other stories at planetary.org. I'll be back with author Mark Wolverton right after

Emily.

Hi, I'm Emily Lochuwala with questions and answers. A listener asked, what happened to Mars's ancient

atmosphere? Most but not all scientists agree that during Mars's early history the

atmosphere was much thicker than it is today.

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