Observatory on Instagram: "In the move - Interstellar, Cooper experiences gravitational time dilation - a real effect predicted by Einstein’s theory of relativity. When he and the crew land on Miller’s planet, it’s orbiting close to a massive black hole called Gargantua. The gravity there is so strong, it literally slows down time. Just 1 hour on that planet equals 7 years on Earth. So while Cooper and Brand spend only a few hours there, 23 years pass for people back home - including his daughte