What should be the roles of humans and robots in space exploration, including the search for life beyond Earth? This question will be important for the newly announced NASA goal of human landings on the Moon by 2024, followed by a lunar outpost and future human flights to Mars.
Sometimes this issue is posed as a binary choice: humans or robots. But this oversimplifies the issues. First, the answer is almost certainly context dependent. It should be discussed separately depending on the mission being considered. For example, humans might be very useful in exploring the Moon or Mars, but they certainly are not appropriate for the moons of Jupiter. Humans are important on the International Space Station, but they would be worse than useless for an astrophysics mission. Second, this really is a false dichotomy. Humans are deeply involved in all space missions, but in an age of telepresence and artificial intelligence, they do not necessarily need to be physically present. As one example, consider a human on Mars’s moon Phobos teleoperating a vehicle on the martian surface; she would not be on Mars, yet certainly she would be part of a space mission. Or compare that with the same human on Earth teleoperating a vehicle on the mar-tian surface. Where do we draw the line? How important is it for a human to be physically on another world?