The Bizarre Behaviour Of Rotating Bodies

What you are looking at is known as the Dzhanibekov effect or the tennis racket theorem or the intermediate axis theorem. It involves arguably the best mathematician alive, Soviet era secrets, and the end of the world. So in 1985, cosmonaut Vladimir Dzhanibekov was tasked with saving the Soviet space station Salyut 7 which had completely shut down. The mission was so dramatic that the Russians made a movie out of it in 2017 and after rescuing the space station, Dzhanibekov unpacked supplies sent up from Earth which were locked down with a wing-nut and as the wing-nut spun off the bolt, he noticed something strange: The wing-nut maintained its orientation for a short time, and then it flipped, 180 degrees. And as he kept watching, it flipped back a few seconds later and it continued flipping back and forth at regular intervals. This motion wasn’t caused by forces or torques applied to the wing-nut: there were none. And yet it kept flipping. It was a strange and counterintuitive phenomenon. One that the Russians kept secret for 10 years.


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