Guest: Steven Squyres, Professor of Astronomy at Cornell University.

Twin robotic explorers Spirit and Opportunity have added a great deal to our understanding of Mars. Among other things, they have found substantial evidence that at one time, there was water on the surface of the planet. Today on Focus, Cornell University astronomer Steven Squyres talks us through what we know so far and the big question... was there ever life on the Red Planet?

Guest: Robert Zubrin.

Will astronauts ever return to the moon? Will they venture beyond our own system to other planets? This morning on Focus, we'll discuss Space Shuttle design, interplanetary travel, and Mars missions with former NASA engineer Robert Zubrin, worked on the design of advanced space transportation and propulsion as well as the development of strategies for the exploration of Mars during his time with the space agency.

A discussion about the future of America's space program with expert John M. Logsdon, Director of the Space Policy Institute, George Washington University. 

Guest: Andrew Mishkin.

Sojourner's diminutive size didn't stop it from captivating millions of people when it beamed back the first-ever photos from the red terrain of Mars. But the Pathfinder mission's story goes far back beyond that first contact. NASA engineer Andrew Mishkin joins us today on Focus to give us the details on the massive effort made by the world's best minds to land an artificial intelligence on the surface of Mars.

Guest: Ken Croswell.

Mars is one of the brightest and most beautiful planets—and it may also hold the key to the question of whether life exists elsewhere in the universe. Today on Focus we're joined by astronomer and writer Ken Croswell. His new book Magnificent Mars talks about the geology, topography, and atmosphere of the planet, as well as the spacecraft due to land on its surface within the next few weeks. What do we hope to learn from these latest missions to the Red Planet? This morning, Croswell will be answering that question—and more.