Back in 1884, a Swiss astronomer by the name of Arndt made headlines when he claimed to have discovered a very curious planet in an orbit beyond Neptune — a surprisingly cubical planet.
Of course even in 1884, everyone knew this was bunk. The New York Times even ran a piece titled “The Cubical Planet” in their Nov. 16 edition. As informative as it is stuffy, the Gilded Age article interviews physicist Dr. Theodore Vankirk, who first dismisses the prospect of a square planet as pure hooey, and then proceeds to wax scientific about just what a cube world would be like. It all comes down to gravity. On our spherical Earth, gravity pulls “down” us toward the planet’s center of mass. So on a flat surface, we naturally stand up straight.
A hypothetical cube world, however, would feature six square faces and you’d only encounter up/down gravity toward the centers of these regions. As you traveled closer and closer to the edge, it would feel like you were walking up an incline and it would be difficult to stand up straight because the gravitational pull would draw you toward the center of the massive cube, which wouldn’t lie directly beneath your feet. Standing on the “edge” of this cube world would feel like standing atop a mountain range. Contemporary cosmologist Karen L. Masters also finds the topic of cube worlds fascinating — especially the atmospheric possibilities. As she explains in Cornell’s Ask a Physicist feature, all six faces of the plant aces would boast temperate weather, centralized bodies of water and none of them would feature polar or equatorial weather. What’s more, the pointy edges of the cube would actually poke through the planet’s atmosphere like titanic mountains. Here’s her explanation : Let’s assume that the atmosphere goes up 1000 km above the Earth (when it is a sphere), and so is a sphere itself of radius 6400km+1000km=7400km. This should be about the right number. A cube with the same volume as the spherical Earth would have a side 10,000 km (6,400 miles) long so the corners are 8700 km from the center! They would definitely stick out above the atmosphere.
