The moment of first contact with extraterrestrials is a staple of science fiction. It usually involves a frantic scientist having a Eureka moment, realising in a single dramatic instant that Earth is being visited by creatures from light-years away. Aliens are in the public consciousness once again thanks to Steven Spielberg’s latest film, Disclosure Day, which follows a whistleblower’s attempts to reveal extraterrestrial visitations to the world. In reality, the discovery of extraterrestrial in