Robert Zubrin is an American aerospace engineer and author, best known for his advocacy of human exploration of Mars with his Mars Society Organization. He and his colleague at Martin Marietta, David Baker, were the driving force behind Mars Direct, a proposal in a 1990 research paper intended to produce significant reductions in the cost and complexity of such a mission. Robert established the Mars Society in 1998. This is an international organization advocating a human mission to Mars as a goal.