No, these are actually referring to the gyroscopic sensors on the spacecraft. This article [0] makes it a little bit more clear. While there are actuators that

No, these are actually referring to the gyroscopic sensors on the spacecraft. This article [0] makes it a little bit more clear. While there are actuators that use gyroscopic torque, referred to as Control Moment Gyros (CMG) Hubble uses reaction wheels for pointing the spacecraft. [0] https://science.nasa.gov/mission/hubble/observatory/design/hubble-one-gyro-mode/ https://science.nasa.gov/mission/hubble/observatory/design/h...