The European Space Agency’s LISA Pathfinder spacecraft is on its way to space with the Disturbance Reduction System (DRS), a thruster technology developed at NASA's Jet Propulsion Laboratory. The DRS uses colloid micronewton thrusters, the first of their kind, to keep the spacecraft as still as possible and compensate for solar pressure. These thrusters electrically charge small liquid droplets and accelerate them through an electric field in order to generate thrust.
The thrusters will deliver 5 to 30 micronewtons of thrust (about the weight of a mosquito) continuously, with exquisite precision, to counteract the force of sunlight. The DRS microthrusters aim to control the spacecraft's position to within a millionth of a millimeter, using software provided by NASA's Goddard Space Flight Center. The DRS may also be used for formation flying. For example, a constellation of small satellites could incorporate the thrusters in order to be perfectly synchronous while flying together.