Spirit, the first of two Mars Exploration Rovers, has begun its journey to the Red Planet. Dr. Joy Crisp is Project Scientist for the mission at the Jet Propulsion Laboratory. She tells us about her job and how she got there on this week's show. Bruce Betts has another trivia contest, and news from his friend, Biff Starling the Astrobot. Emily Lakdawalla is on the trail of the missing Martian atmosphere.