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by accrual 405 days ago
Reminds me of the tumbling T-handle. A small tool is spun up in one axis, and due to some interesting physics, ends up flipping over on another axis every few seconds.

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

1 comments

I wonder if it's reproducible in vacuum or the air is necessary to destabilize it?
It's about angular momentum and happens whenever the axis of rotation differs - even slightly - from the semi-major axis. Interaction with a fluid is not necessary.

You can demonstrate it at home with your smartphone (or, more canonically, a tennis racket), and see for yourself that the tumbling happens much too quickly to be explained by whatever force the air is imparting.