In a rebroadcast from October 11, 2009, Keith talks with Brenda Buck, Assistant Professor of Geoscience, University of Nevada, Las Vegas. Buck talks about how the earth's surface has evolved over time due to to changes in chemistry and biology. She also talks about the Mars-like Atacama Desert in Chile, the most arid desert on Earth, and why research there could help scientists learn how to search for life on the red planet.
Aired June 30, 2013.