This is Science Friday. I'm Irafledo. As we make our way towards the end of the year,

it's a good time to step back and take a look at the big picture. And I mean really big.

Few people could put the cosmos in perspective better than the late astronomer Carl Sagan.

And that's why we're taking this opportunity to take another listen to this classic conversation with Sagan,

recorded 25 years ago this month.

His famous book, Pale Blue Dot, had just been published.

And as you'll hear, the development of a movie called Contact was still just in the planning stages.

We talk about U.S. space policy, the search for extraterrestrial intelligence, and the place of humans in the universe.

Here's Carl Sagan on Science Friday, recorded December 16, 1994.

We'd all like to think that we're pretty much the center of attention, the center of the universe.

But in the words of Carl Sagan, we live on a routine planet near a humdrum star stuck away in an obscure corner of an unexceptional galaxy,

which is just one of a hundred billion galaxies in the universe.

And if you think that sounds depressing, consider this.

There is no guarantee that our boring little rocky planet will be around forever.

If we don't destroy it, maybe a stray asteroid will.

And so where does that leave us? Astronomer Carl Sagan might say it brings

us back to our roots as explorers and may drive us to become interplanetary, even intergalactic

wanderers. Now let me welcome my guest. Dr. Carl Sagan is the David Duncan Professor of

Astronomy and Space Science and the director of the Laboratory of Planetary Studies at Cornell University in Ithaca, New York.

He is co-founder and president of the Planetary Society and author of the new book,

Pale Blue Dot, published by Random House, and it's my pleasure to welcome, Dr. Sagan.

Welcome to the program.

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