Mesmerising Dzhanibekov Effect

From Superinnovators 24/01/24

The Dzhanibekov Effect, also known as the tennis racket theorem, is a phenomenon in classical mechanics that occurs during the rotation of an object with three distinct momenta of inertia.

When such an object, like a T-handle, wingnut or tennis racket, is tossed in the air with a spin around its intermediate axis, it unexpectedly flips its orientation.

This surprising behaviour, most powerfully observed in microgravity, is due to the instability inherent in rotation around the intermediate axis.

The effect, named after Soviet cosmonaut Vladimir Dzhanibekov who first observed it in space in 1985, highlights the complex dynamics of rotational motion.

More info:

https://en.wikipedia.org/wiki/Tennis_racket_theorem

https://rotations.berkeley.edu/a-tumbling-t-handle-in-space/

Chinese astronaut demonstrating Dzhanibekov Effect

Composite video of a tennis racquet rotated around the three axes – the intermediate one flips from the light edge to the dark edge (note that the numbering is off-set by 1 from the diagram above). Credit: Wikipedia