We all have a lot of questions about Mars. Recently, at a National Geographic Live event in Seattle, we collected quite a few. Luckily for us, Dr. Ray Arvidson, planetary geologist and professor at Washington University in St. Louis, has answers! Dr. Arvidson directs the Earth and Planetary Remote Sensing Laboratory, and has worked on the Mars Exploration Rover (Spirit and Opportunity) and the Mars … Continue reading Mars Questions? We’ve Got Answers.