Are we alone in the universe? Some scientists are attempting to answer this question by exploring the closest planet most similar to Earth–Mars. There are two main ways of studying the surface of Mars. Rovers, like Opportunity and Curiosity, are currently operating on the planet. The other method is satellites. Dr. Deanne Rogers, assistant professor in the Geosciences Department at Stony Brook University, uses satellites to search for signs of past Martian life.