Reaction wheel

A reaction wheel is a device used to help control spacecraft and satellites in place of thrusters. Reaction wheels have a heavy rotor and sometimes gimbals, allowing them to gradually turn the vehicle they are mounted to using the momentum of the spinning parts.

Reaction Wheel Media

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  A small reaction wheel viewed in profile

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  A momentum/reaction wheel comprising part of a high-accuracy Conical Earth Sensor to maintain a satellite's precise attitude