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Plasma Ben

Watch: WTF Is Going on With This Object Spinning in Zero Gravity?

BEC CREW
21 AUG 2015

If ever there was a symbol for what astronauts put themselves through in the name of science, it would be this crazy spinning T-handle. Up there in the zero-gravity environment of the International Space Station (ISS), everything happens according to a completely different set of rules, and the things you take for granted on Earth suddenly no longer apply. For example, in zero gravity, your sweat doesn't evaporate, there's a constant concern that your eyeballs might be going flat, and carbonated beverages hurt because it's physically impossible to burp out all that extra gas. But as that T-handle so elegantly demonstrates, we can learn so much from what's going on.

 

Found recently by Digg, the video above shows an astronaut spinning a T-handle in the SpaceDRUMS (Space Dynamically Responding Ultrasonic Matrix System) facility aboard the ISS, and as they so delicately point out, "You thought things in space pretty much follow the rule 'go in one direction forever' right? Well it turns out you are wrong and not a physicist."

For those of us who aren't physicists, what's going on here? Our friend Henry Reich from MinutePhysics actually discusses it in the video below, when he was lucky enough to ask astronaut Scott Kelly to demonstrate it using a Leatherman tool. He calls it the "instability of rotation around the intermediate axis of an object," and explains that if you rotate an object around its largest and smallest axes, it will spin in a stable, consistent manner.

But if you rotate it on an intermediate axis (watch the video below to see what he means), the rotation is unstable. The object will flip back and forth in orientation as it spins, because it's trying to spin itself on the more stable large or small axes instead. The only difference between how this works on Earth and in zero gravity is that in space, you can actually see the results of this instability without the help of slow-motion footage.

Watch the footage of Scott Kelly trying it out for himself, it's like a crazy, uncoordinated dance, but there's a certain grace and dignity to it too (yes I'm talking about an inanimate object. And yes, I'll show myself out):