Humans have known for thousands of years that the planet is round, yet the belief in a flat Earth refuses to die. Let us imagine what our planet would be like if it was indeed flat.
First of all, a flat planet might not have any gravity. It's unclear how gravity would work, or be created, in such a world, says James Davis, a geophysicist at Columbia University's Lamont-Doherty Earth Observatory.
Watch the above video to find out more.