The Ganymede Laser Altimeter – Instrument design overview with radiation hard transmitter

The JUICE (Jupiter Icy Moons Ex-plorer) mission is part of ESA‘s Cosmic Vision Programme and its objective is to study Jupiter‘s plasma environment and the three icy moons Ganymede, Eu-ropa and Callisto. The JUICE spacecraft will be launched in 2022 on an Ariane 5 rocket. After its 8 year cruise it will enter an orbit around Jupiter. During the following three years the orbit will be gradually adjusted and after several fly-bys at Callisto, Europa and Ganymede the spacecraft will reach its final circular orbit around Gany-mede. One of the ten scientific instruments is the Ganymede Laser Altimeter – GALA. It will determine the topography and time dependent shape of the moon by direct laser altimetry approach. This talk presents the instrument design of GALA with the focus on the transmitter laser. In particular radiation hardness and efficiency aspects are explained.