TANPOPO, dandelion, is the name of a grass whose seeds with floss are spread by the wind. We propose the analyses of interplanetary migration of microbes, organic compounds and meteoroids on ISS-JEM. Ultra low-density aerogel will be used to capture micrometeoroid and debris. Particles captured by aerogel will be used for several analyses after the initial inspection of the gel and tracks. Careful analysis of the tracks in the aerogel will provide the size and velocity dependence of debris flux. The particles will be analyzed for mineralogical, organic and microbiological characteristics. To test the survival of microbes in space environment, microbial cells will be exposed. Organic compounds are also exposed to evaluate the possible denaturation under the conditions. Aerogels are ready for production in Japan. Aerogels and trays are space proven. All the analytical techniques are ready.

  A great number of experiments have been done to examine possible prebiotic formation of bioorganic compounds such as amino acids in possible primitive environments. There are two scenario of prebiotic formation of bioorganic compounds: An endogenous formation scenario and an exogenous formation scenario. The latter scenario was supported by the facts that a wide variety of organic compounds were detected in meteorites and comets. It is now suggested that organic compounds in extraterrestrial bodies were originally formed in extremely cold environments such as in molecular clouds. Laboratory experiments showed that complex precursors of amino acids could be formed from simulated interstellar media by irradiation with high-energy particles. It was suggested that such extraterrestrial organic compounds were delivered mainly by cosmic dusts. We have, however, very limited information on organic compounds in cosmic dusts since they are captured within terrestrial environments. We proposed a novel astrobiology mission “Tanpopo” by utilizing the international space station. In the mission, cosmic dusts will be collected with ultra-low-density aerogel, and organic compounds in them will be analyzed. In the mission, organic compounds simulating extraterrestrial organics will be directly exposed to solar ultraviolet light and cosmic rays at the same time to study the fate of organic compounds in cosmic dusts near the Earth orbit.

  Analyses of organic compounds in the extraterrestrial materials, e. g. carbonaceous chondrites, micrometeorites, and cometary dust, are important for the study of origins of life on the Earth, since the terrestrial living organisms are formed by highly organized organic compounds and, organic compounds and their source materials should be transported into the Earth from the outside of the Earth. To avoid the contaminants from the terrestrial organisms is the most important for organic analyses of the extraterrestrial materials. Therefore, intact micrometeoroids captured on the exposure facility of the “Kibo” module at the International Space Station by “TANPOPO” mission are suitable for the astrobiological studies concerning with origins of life. In this review, organic analyses of extraterrestrial materials are summarized and tasks for the analyses of organic compounds in the sub-mm sized micrometeoroids, especially captured particles in the “TANPOPO” mission, are described.