scott <sco### [at] laptopcom> wrote:
> "Each turn robs the planet of angular momentum"

> Unfortunately not...

  I don't see, technically speaking, why not.

  Let's assume we have a big object in a weightless space in vacuum
rotating. Can this rotation be stopped by the object itself without
applying external forces?

  The answer is yes. The most obvious way to do this is to fire up some
rockets in specific directions. This causes the rotation to slow down,
basically by expelling material at high speed from the object.

  A slightly less obvious way is to rotate some significant part of the
object at a different speed. Why does this slow down the overall rotation?
It's because part of the angular momentum is converted into heat due to
friction, and this heat dissipation is taken away from this angular momentum.

-- 
                                                          - Warp

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