A colloid thruster (or "electrospray thruster") is a type of low thrust electric propulsionrocket engine that uses electrostatic acceleration of charged liquid droplets for propulsion. In a colloid thruster, charged liquid droplets are produced by an electrospray process and then accelerated by a static electric field. The liquid used for this application tends to be a low-volatility ionic liquid.
Like other ion thrusters, its benefits include high efficiency, thrust density, and specific impulse; however it has very low total thrust, on the order of micronewtons. It could provide very fine attitude control or efficient acceleration of small spacecraft over long periods of time.
Flight use
An electrospray thruster is planned to be used in space on the ST-7 LISA Pathfinder mission, to demonstrate disturbance reduction.
