ScienceHubble Uses Reaction Wheels and Magnetic Bars for Steering
The Hubble Space Telescope changes its orientation by adjusting the speeds of four internal reaction wheels, causing it to rotate without firing thrusters, which it lacks. To manage excess momentum, magnetic torquer bars interact with Earth's magnetic field to unload it. This propellant-free steering system has been in use since 1990, enabling precise movement between galaxies.
Spacedaily·


