The Tanpopo experiment was the first Japanese astrobiology mission on board the Japanese Experiment Module Exposed Facility on the International Space Station (ISS). The experiments were designed to address two important astrobiological topics, panspermia and the chemical evolution process toward the generation of life. These experiments also tested low-density aerogel and monitored the microdebris environment around low Earth orbit. The following six subthemes were identified to address these goals: (1) Capture of microbes in space: Estimation of the upper limit of microbe density in low Earth orbit; (2) Exposure of microbes in space: Estimation of the survival time course of microbes in the space environment; (3) Capture of cosmic dust on the ISS and analysis of organics: Detection of the possible presence of organic compounds in cosmic dust; (4) Alteration of organic compounds in space environments: Evaluation of decomposition time courses of organic compounds in space; (5) Space verification of the Tanpopo hyper-low-density aerogel: Durability and particle-capturing capability of aerogel; (6) Monitoring of the number of space debris: Time-dependent change in space debris environment. Subthemes 1 and 2 address the panspermia hypothesis, whereas 3 and 4 address the chemical evolution. The last two subthemes contribute to space technology development. Some of the results have been published previously or are included in this issue. This article summarizes the current status of the Tanpopo experiments.

中文翻译：

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Tanpopo的科学目标：国际空间站日本实验舱暴露设施的天体生物学暴露和微流星体捕获实验

Tanpopo 实验是国际空间站（ISS）日本实验舱暴露设施上的第一个日本天体生物学任务。这些实验旨在解决两个重要的天体生物学主题，即全精子症和朝向生命产生的化学进化过程。这些实验还测试了低密度气凝胶并监测了近地轨道周围的微碎片环境。确定了以下六个子主题来实现这些目标： (1) 在太空中捕获微生物：估计近地轨道微生物密度的上限；(2) 空间微生物暴露：估计空间环境中微生物的生存时间过程；(3) 国际空间站上的宇宙尘埃捕获和有机物分析：探测宇宙尘埃中可能存在的有机化合物；(4) 空间环境中有机化合物的变化：评价有机化合物在空间中的分解时间过程；(5) Tanpopo超低密度气凝胶的空间验证：气凝胶的耐久性和颗粒捕获能力；(6) 空间碎片数量监测：空间碎片环境随时间变化。子主题 1 和 2 涉及泛精子学假设，而子主题 3 和 4 涉及化学进化。最后两个子主题有助于空间技术的发展。一些结果已在之前发表或包含在本期中。本文总结了 Tanpopo 实验的现状。(5) Tanpopo超低密度气凝胶的空间验证：气凝胶的耐久性和颗粒捕获能力；(6) 空间碎片数量监测：空间碎片环境随时间变化。子主题 1 和 2 涉及泛精子学假设，而子主题 3 和 4 涉及化学进化。最后两个子主题有助于空间技术的发展。一些结果已在之前发表或包含在本期中。本文总结了 Tanpopo 实验的现状。(5) Tanpopo超低密度气凝胶的空间验证：气凝胶的耐久性和颗粒捕获能力；(6) 空间碎片数量监测：空间碎片环境随时间变化。子主题 1 和 2 涉及泛精子学假设，而子主题 3 和 4 涉及化学进化。最后两个子主题有助于空间技术的发展。一些结果已在之前发表或包含在本期中。本文总结了 Tanpopo 实验的现状。最后两个子主题有助于空间技术的发展。一些结果已在之前发表或包含在本期中。本文总结了 Tanpopo 实验的现状。最后两个子主题有助于空间技术的发展。一些结果已在之前发表或包含在本期中。本文总结了 Tanpopo 实验的现状。