For nearly 2 years the 3rd ESA EXPOSE mission, the 2nd on the Russian Zvezda module of the ISS, exposed a variety of astrobiological samples to space and simulated Mars environmental conditions. Various chemical compounds and organisms like bacteria, archaea, fungi, plant seeds, lychens, mosses and animal eggs and larvae from the international experiments BIOMEX, BOSS, P.S.S. and the IBMP-experiment were exposed to space vacuums dryness, extraterrestrial short wavelength UV, radiation and temperature oscillation or Mars-like conditions comprised of a 980 Pa pressure CO₂ dominated gas mixture and solar UV modulated to simulate Mars surface solar radiation. The complete mission was simulated under ESA contract in the Planetary and Space Simulation facilities at DLR Cologne according to mission data received from the ISS and to UV radiation calculations by RedShift.