Unlike the late Sagan, who communicated to the general public through books and television shows, Lebofsky has focused on workshops and presentations for science teachers and their students. "I've reached probably 4,000 to 5,000 teachers, and several tens of thousands of students," he says.

Lebofsky, who finances such workshops through grants from the National Science Foundation and other agencies, aims to put space science and technology into a meaningful "context" for teachers and students, he says.

For example, he's encouraged students in mountainous states like Arizona to build accurate scale models of the martian volcano Olympus Mons. They discover that while Olympus Mons is over three times taller than Everest, it also covers an area the size of Arizona -- and thus slopes upward at a gentle 5 degrees.

In other workshops, he's used images of Mars to show the importance of binocular or two-eyed vision in estimating distance. Without 3-D data provided by a nearby camera, he explains, it would have been impossible for the Sojourner rover to maneuver among rocks in the martian landscape.