BIOPAN is a multi-user research program by the European Space Agency (ESA) designed to investigate the effect of the space environment on biological material. The experiments in BIOPAN are exposed to solar and cosmic radiation, the space vacuum and weightlessness, or a selection thereof. Optionally, the experiment temperature can be stabilized. BIOPAN hosts astrobiology, radiobiology and materials science experiments. The BIOPAN facility is installed on the external surface of Russian Foton descent capsules protruding from the thermal blanket that envelops the satellite.