Bennu the Dust Bunny
The Allegory of the Vacuum Cleaner: A Thought Experiment on Space and Dust Close your eyes and imagine the floor of your house, specifically the corners, the hard-to-reach places where nobody ever goes. Look at that dust. On Earth, when you sweep, you find piles of dust in hard-to-reach places. The dust doesn't stay evenly dispersed; it gathers in clumps, in bunches, in tangles. The clumps get brushed-aside by normal foot traffic. You might even see it swirling into little tornadoes when you walk past. Why? Because on Earth, gravity rules. It pulls everything down, flattening the world. But dust is light, and it has a secret: it clings together. When you look closely at that dust bunny, you are seeing the result of “van der Waals forces.” These are the tiny, invisible magnets of the universe. Even though the dust particles are electrically neutral, their electron clouds fluctuate, creating momentary dipoles. They attract. But on Earth, gravity is so strong that it overpowers...