ESA-space experiments: from BIOPAN 6 experiment "Lithopanspermia" to EXPOSE
ABSTRACT The experiment Lithopanspermia and the experiment Life: The concept of both of the space experiments is to expose different eukaryotic species as there are the lichens Xanthoria elegans, Rhizocarpon geographicum and their mycobiont cultures, the black Antarctic microfungi Cryomyces minteri and Cryomyces antarcticus and Antarctic rocks colonized by cryptoendolithic communities. The aim behind this space research is to analyze the likelihood of Panspermia, which means the interplanetary transfer of life. Whereas the BIOPAN 6 experiment is a short time space experiment with 10 days space exposure, the experiment on the EXPOSE platform on the ISS is a long term experiment of about 1 years of space exposure what is a good tool to realize the second scenario of Panspermia, which means the travel of microorganisms through space. Experiment verification tests: investigations on the mentioned eukaryotic model organisms were still done during experiment verification tests (EVTs) and indicated a relevant high survival capacity. Nearly 70 to 90% of the lichens and up to 70% black microfungi have survived the tests before space exposure experiments. This has been checked by culturing methods, by the use of LIVE/DEAD staining investigations and in case of lichens additionally by photosynthesis activity tests. Space exposure: samples of the same model organisms were used for the space exposure experiments partly on BIOPAN 6 (FOTON M3) and completely on the ISS. The exposure time was between 10 days and 1 years and the results are indicating still maintenance of viability and even a preserved physiologic activity.