It’s one of the great questions of our age: Are we alone in the universe? A long line of films—from Contact to Close Encounters of the Third Kind to the latest entry, Arrival—have explored whether intelligent life is somewhere out there in the cosmos and wondered what would happen if, or when, we finally come face-to-face with it.

Now, to get the scientific perspective on extraterrestrials, National Geographic has turned to a comedian, albeit one who pursued a Ph.D. in physics. The host of the British TV show It’s Not Rocket Science, Ben Miller has recently published a book called The Aliens Are Coming! The Extraordinary Science Behind Our Search for Life in the Universe.

Speaking