Space Programs

Satellites and Spacecraft

How do satellites and spacecraft move in space?

Once in space, satellites need only a small amount of force to move—either to speed up or slow down, or to change direction and orientation. Small rocket engines (often referred to as thrusters) are usually sufficient. Even small rocket thrusters, however, require large amounts of fuel over time, which weighs down the spacecraft and reduces the payload. Spacecraft designers now use new technologies to move things around in space, such as ion propulsion engines.


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