Try to make the pendulums move in the same way 3 times in a row.
Does it work? No, each time they do something entirely different. It’s complete chaos. After all, it’s two times a double pendulum: on each side of the pivot point there is a pendulum with a pendulum attached. Try starting the double pendulums in a slightly different position or at a slightly different speed. Then you’ll see a completely different pattern appear.
So it seems unpredictable what the double pendulums will do.. In fact… it’s not. If we know the initial positions exactly, we can actually predict the movements. At least, scientists who specialise in chaos theory can. They create order in the chaos.
Chaos in the weather forecast
Sound familiar? You go on a school trip. The weather forecast said it would be sunny, so you take your sunglasses with you. An hour later … it’s pouring with rain. How annoying! But why is the weather forecast sometimes wrong?
That’s because the weather is chaotic. To know what weather we will get, meteorologists make weather models. With mathematical calculations which imitate, for example, air currents, these models predict the future weather. But a small change in such a model can have an enormous impact. Such as rain instead of sun.
Chaos on Pluto’s moons
Pluto has not 1, but 5 moons! Astronomers discovered that two of them, Nix and Hydra, rotate chaotically around their axis. So their movements also seem unpredictable. Sometimes they turn faster, sometimes slower and sometimes they simply rock back and forth.