ESA's (European Space Agency) LISA (Laser Interferometer Space Antenna) Pathfinder spacecraft demonstrated technologies required for LISA, a future space probe designed to detect ripples in space-time called gravitational waves. NASA provided the mission’s disturbance reduction system, which consisted of a novel type of precision thruster and specialized controls for achieving drag-free flight. NASA scientists also participated in the science operations and analysis of LISA Pathfinder data.