The team travels across Great Britain to investigate evidence that suggests the search for alien life may lie within Earth's own solar system. Off the east coast of Scotland, Chris Lintott meets Claire Cousins, who explains the fundamental conditions needed for life, while Maggie Aderin is in Milton Keynes to meet Mark Fox-Powell, whose team are recreating the freezing conditions of the icy moons of Jupiter and Saturn in the lab to understand how chemistry behaves there