Whenever the state of the Earth seems discouraging, we look to outer space. The Space Race of the ‘50s and ‘60s took place against a backdrop of the Vietnam War, civil rights protests and the Cuban Missile Crisis. Now, NASA’s journey to Mars and the discovery of new solar systems are welcome respite from a world in which the US president endorses neo-Nazis, Europe deals with a spate of terror attacks and the UK faces up to the implications of Brexit.