The Weird Thing An Astronaut Noticed In 1985

In this video, viewers are taken back to 1985, when a Soviet cosmonaut aboard the Mir space station casually released a small handle in zero gravity and noticed something deeply strange: as it rotated, it repeatedly flipped 180 degrees around its long axis, over and over, without any external force acting on it. What looked like a simple curiosity turned out to be a striking real-world demonstration of a counterintuitive principle of rotational dynamics now known as the tennis racket theorem, or the Dzhanibekov effect. The footage shows how objects rotating around their intermediate axis are inherently unstable, transforming an everyday tool into visual proof of a theorem that had long existed only on paper.

WATCH:

In 1985 an astronaut noticed this physical behavior of a handle, that turned out to be the proof of a theorem: the tennis racket theorem (also dubbed the Dzhanibekov effect). pic.twitter.com/cPoPdItJqr

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