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> Wondering if this technology can be used to control spacecraft attitude

It can indeed, and is already used in the wild today!

https://en.wikipedia.org/wiki/Reaction_wheel#Examples_of_spa...

That list has three examples, but to be clear for others: Nearly every satellite has reaction wheels. There are literally tens of thousands of reaction wheels in orbit.

I guess I have watched Apollo 13 too many times and was under the mistaken impression spacecraft still used propellant thrusters for attitude control.

They still do!

To add, reaction control is used in conjunction with reaction wheels. When the wheels saturate, the rockets are used to desaturate them.

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