Freeman Dyson, climate-change denier, has also said “no” to humans as a pivotal part of space exploration, despite once believing flying Mayflowers would eventually land on asteroids. Dyson says machines must do the pioneering and if we want to colonize worlds beyond our own, we have to spend centuries devising and executing such “urban planning” and need to be open to altering our physiology. Listen to audio of these and other Dyson ideas at Raw Science.•