EXPOSE-R with its 8 experiments and approximately 1200 individual samples shall contribute to the question of life’s origin on Earth. Lead-managed by the radiobiology division of the DLR - Institute of Aerospace Medicine and in close cooperation with the Rheinisch - Westfälische Technischen Hochschule Aachen (RWTH Aachen) and the Technical University Munich (TUM) the experiment "Spores – Spores in artificial Meteorites" is operated. This is one of the 6 astrobiological experiments on the ISS of the „ROSE-Consortiums" (Response of Organisms to Space Environment) coordinated by DLR. Additionally integrated into the EXPOSE-R facility are several dosimeters monitoring the ionising and the solar UV-radiation during the mission to deliver useful information to complement the sample analysis.
The involved scientists investigate the question whether life in the form of microorganisms may have been transported embedded in meteorites from one planet to another and if life necessessarily originated on Earth. Each tray is loaded with a variety of biological samples including plant seeds and spores of bacteria, fungi and ferns that will be over layered or mixed with meteorite material. Outside Earth's protective atmosphere, the organisms will be exposed to solar ultraviolet (UV) radiation, vacuum, cosmic rays and extreme temperature variations as the ISS repeatedly passes between areas of direct sunlight and the cold darkness of Earth's shadow. Afterwards the investigators determine the survival rate of the organisms.
At the end of the exposure period, the Expose-R trays will be retrieved from their location outside the Station and returned to Earth on a Russian Soyuz spacecraft. From the landing site in Kazakhstan, the trays will be returned via Moscow to the Microgravity User Support Centre (MUSC) in Cologne, Germany. The radiobiology division of the Institute of Aerospace Medicine will disassemble the various samples and distribute them to the international scientists for further investigation in their individual laboratory. The analysis of the effect of the space parameters on different biological endpoints of the spores of the microorganism Bacillus subtilis will be carried out at the radiobiology division.
Parallel to the space mission an identical set of samples is accommodated into an EXPOSE-R facility identical in construction to perform the Mission Ground Reference (MGR) Test. During MGR Test carried out in the Planetary and Space Simulation Facilities (PSI) of DLR, Cologne the space parameters (vacuum, temperature and extra-terrestrial UV-radiation) as delivered by telemetry are simulated. In the DLR PSIs the mission preparing EXPOSE EVT (Experiment Verification Test) Program was performed.
The Expose-R and -E experiments are part of ESA’s European Astrobiology Programme for Life and Physical Sciences (ELIPS) in the frame of ESA’s Directorate of Human Spaceflight. - studying the origin, evolution and distribution of life in the Universe.