The European Space Agency (ESA) will launch the LISA (Laser Interferometer Space Antenna) Pathfinder satellite this month. Its 12-month mission is to test measuring instruments whose qualification is only possible in space. One such instrument is Kugler GmbH's gold-platinum cube for measuring gravitational waves. Gold-platinum cube. Courtesy of Kugler GmbH. The test device weights 150 kg and is 64 × 38 × 38 cm. It contains two vacuum chambers at a distance of about 40 cm, each of them holding a gravitational free-falling, cube-shaped test mass made from a gold-platinum alloy and having an edge length of 46 mm. The main payload is a laser interferometer, which determines the distance of the two cubes. The test values are used to precisely control the satellite's position and keep the cubes centered, thereby drawing on an ultraprecise micropropulsion system. ESA has commissioned Airbus Defence and Space Ltd. to build and deliver the ready-to-launch integrated satellite.