Optical component and instrument developer Optical Surfaces Ltd. has been selected by Hensoldt Optronics GmbH to supply key precision optics for optical testing the Ganymede Laser Altimeter (GALA), one of 10 scientific instruments on board the Jupiter Icy Moon Explorer (JUICE) mission. The JUICE mission is part of the European Space Agency’s (ESA’s) cosmic vision program with the objective to study Jupiter’s plasma environment and the three icy moons Ganymede, Europa, and Calisto. The JUICE spacecraft will be launched in 2022 on an Ariane 5 rocket. After its eight-year voyage, it will enter an orbit around Jupiter. During the following three years, the orbit will be gradually adjusted, and after several flybys at Callisto, Europa, and Ganymede, the spacecraft will reach its final orbit around Ganymede. GALA will be used to determine the topography and time-dependent shape of the moon by a direct laser altimetry approach. The GALA instrument is composed of a transceiver unit, a laser electronics unit, and an electronics unit, all designed to withstand the challenging environment of Jupiter. At the heart of the transceiver unit is a lightweight Ritchey-Chrétien telescope incorporating precision optics capable of providing topographical vertical resolution of less than 5 m, and of accurately measuring radial tidal deformations of the moon's "ice shell." Hensoldt selected Optical Surfaces Ltd. to manufacture and supply a 550-mm-diameter off-axis parabolic mirror and two 600-mm-diameter identical folded flat mirrors for optical verification testing of the Ritchey-Chrétien telescope in the GALA instrument. “To be chosen as a supply partner to help enable the JUICE mission is a great honor,” said Aris Kouris, sales manager for Optical Surfaces. “Drawing upon our many decades' experience in building telescope systems, we were able to propose a solution to overcome the considerable difficulties posed by the manufacture and testing of the high-precision optics.” Optical Surfaces is a producer of optical components and systems. Hensoldt Optronics is a provider of technology in the defense and security electronics fields.