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In space, a rocket will keep moving even after the thrusters have stopped working. This is because of Newton's First Law: if there is no force acting on an object, it will keep moving at the same velocity. On Earth, when you stop accelerating a car, it will slow down because of friction, or drag, caused by the air around it. But with no air in space, a rocket has no friction to slow it down. It will keep going at the same speed and in the same direction as it did before the thrusters stopped.