The organic matter in carbonaceous chondrites potentially records a succession of chemical histories that started with reactions in the interstellar medium, followed by reactions that accompanied the formation and evolution of the early solar nebula, and, ultimately, ended with reactions driven by hydrothermal and metamorphic alteration in the meteorite parent bodies. Recent analysis of a broad suite of organic matter isolates (IOM) from many different chondrite classes, groups, and types using NMR and XANE reveal clearly defined reaction pathways that appear to radiate from a simple molecular precursor. We also find, however, that the isotopic signatures of IOM do not correlate in any simple way with reaction history.

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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.

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Two organic analysis, which are organic compounds analysis in the captured micrometeorides and stability experiment under cosmic environments, were proposed in the "Tanpopo" mission. Now, we have performed the simulation experiments for the mission in order to confirm the feasibility and obtaine some comparison data. Firstly, alteration of organic compounds at the capturing was examined by using the two-stage light gas gun at ISAS/JAXA. Insoluble organic matter were able to be collected, without hardly alteration using the ultra low density silica aerogel. Secondly, stability of organic compounds under the high-atomic oxygen environment was examined, since atomic oxygen is abundant at ISS altitude. Weight loss of standard capton film and changing color of PAH were observed.

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Racemic solid films of DL-isovaline were irradiated with circularly polarized light from free electron laser. Circular dichroism spectra of the films after the irradiation showed new Cotton peaks. The signs of the peaks were completely reversed depending on the helicity sign for the circular polarization (left- or right-handed) and, therefore symmetric circular dichroism spectra were obtained. Absorption spectra of the films after irradiation slightly shifted to low-energy direction but the absorption peak profile was hardly changed. The new Cotton peak appearance is due to not simple asymmetric photolysis of the molecule but to chirality emergence caused by construction distortion accompanied with conformation change of the molecule. These results show that abiotic synthesized organic molecules in racemic body on interstellar materials may emerge chirality, whose asymmetric direction is according to the helicity of the circularly polarized light exposed in space.

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When a frozen mixture simulating interstellar dust ice mantle was irradiated with high-energy heavy ions, complex amino acid precursors with large molecular weights were formed. Such complex organics gave enantiomeric excesses after irradiation with CPL. Such organics may have been delivered to the primitive Earth by interplanetary dust particles (IDPs). We are planning the Tanpopo mission, where IDPs are captured on the JEM Exposed Facility of ISS.

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How to polymerize single amino acids into peptides is the most fundamental question for origin of life. In addition, there exist no clear constraints as to which geological conditions are suitable for such peptide formations. We performed several high pressure and temperature experiments. We were successful to polymerize glycine, valine and aspalic acid. The results further suggest that Hadean oceanic crustal conditions were suitable for peptide formations.

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Frequent impacts of extraterrestrial objects melted the embryonic Earth, forming an inorganic body with a CO2 and N2-rich atmosphere. How and when abundant organic molecules appeared in such an inorganic world are fundamental inquiries into the origin of life. Here we report a facile impact synthesis of some biomolecules and their precursors from solid carbon (13C), iron, nickel, water, and nitrogen all of which would have been available during impact events on Earth's early oceans. Geological and geochemical studies on the terrestrial, lunar and meteoritic materials suggest that such impacts were frequent on the Hadean Earth and indicate that ordinary chondrite, the most abundant meteorite, contains a substantial amount of iron-nickel and small quantities of solid carbon. Biomolecules and their precursors identified in the present shock recovery experiments are carboxylic acids (fatty acids), amines, and an amino acid. Therefore impacts of extraterrestrial objects on Hadean oceans might have prepared organic molecules in necessary abundance, variety, and complexity for life's origin, because there might be additional, as yet undetermined, products in the recovered samples and because natural impacts necessarily have greater duration and pressure than those of the experiment.

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A flow-type reactor has been developed, which simulates physicochemical settings of hydrothermal vents, and dehydration condensation of an amino acid, glycine, in hot and compressed aqueous environments is studied.

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I will talk about my experiences through the six-year postdoc life as one case of academic career paths. The talk will includes what I did to get the postdoctoral fellowships and the current assistant professor position, a significance of continuing, being social, and broadening your perspective, my own opinion for 'numbers' of paper, and what I gained via being a postdoc. Hope that the talk will assist undergraduate/graduate students in finding their own paths.

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The study was conducted to determine the concentrations of metals (Cd, Co, Cr, Cu, Mo, Ni, Pb and Zn) and their association with various geochemical substrates in sediments of Old Nakagawa River, Tokyo, Japan. Hall sequential extraction procedure was employed for the fractionation of metals and the concentrations were measured in the liquid extracts by inductively coupled plasma mass spectrometry (ICP-MS). The association of Cd (76-98%) and Zn (48-67%) were found highest with AEC (adsorbed/ exchangeable/ carbonate) phase; Cu (45-60%), Ni (18-40%) and Pb (44-73%) with amorphous Fe oxyhydroxide phase, and the maximum fractionation of Co, Cr and Mo were in both crystalline Fe oxide (12-43, 12-60 and 11-70%, respectively) and amorphous Fe oxyhydroxide phase (20-35, 15-60 and 15-40%, respectively). The observed order of potential trace metal mobility in the aquatic system was: Cd > Zn > Pb > Cu > Ni > Cr > Co > Mo. The sediments of Old Nakagawa River was considered to be polluted on the basis of unpolluted sediments and geochemical background values with respect to Cd, Cr, Cu, Pb, Mo and Zn. Only the AEC fraction was surpassed the toxicological reference values for Cd, Cr, Zn, Cu and Ni recommended by the U. S. Environmental Protection Agency (US EPA). According to the enrichment factors (EFc), geoaccumulation index (Igeo) and pollution load index (PLI), most of the sites have higher values for Cd, Cr, Cu, Pb, Mo and Zn. However, on the basis of marine sediment pollution index (MSPI), the sediment quality range was good to bad although the mean value indicated average quality of sediments of Old Nakagawa River. The study will also make some recommendations to clean up the river systems.

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Dissolved major components and oxygen and hydrogen isotope ratios reveal that the groundwaters <30m depth are recharged by the rain at the Uemachi-daichi (uplifted Pleisocene sediments) and by the seawater and riverwater at the western lowland from the Uemachi-daichi of Osaka City. The seawater invades along the rivers into the shallow groundwater at 3km from the coast.

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To gain a better insight into the influence of redox condition in subsurface shallow sediments that intervene in the formation mechanism of arsenic-contaminated groundwater, detailed geochemistry and mineralogy were studied on modern shallow sediments (up to 5 m thick) including the depth where groundwater table and the associated redox condition change in the dry (December, 2005) and rainy (September, 2006) seasons from the areas at different geological setting and grade of groundwater As contamination in Sonargaon, Bangladesh. Stratigraphic sequences of the studied sediment show three distinct lithofacies, viz. clayey-silt, silty-clay and silty-very fine sand layers, corresponding to fine-grained overbank associations. Total As concentration of the studied sediments ranges from <1 to 16 mg/kg. The comparison of the results of two filed profiles show that slightly increased levels of As are found in the rainy season collected sediments. Sequentially chemical extraction analysis of As reveals that >80 % of As are fixed in insoluble and secondary organic phases, while As in reducible and acid soluble phases is very low (<20%) and changes with respect to the grain size, presence of authigenically formed Fe patches and inversely with the mica content. Total As content varies in accordance with the contents of mica, Al2O3 and Fe2O3, but not that of total organic carbon, indicating that biotite is the major host phase of As. This study is further evident that pyrite and/or other sulfide minerals are not a carrier of As in the study area. In contrast, once As is liberated from biotite due to chemical weathering either from near surface sediments where seasonal cycles the redox conditions or within the aquifer sediments by irregular distribution of local redox conditions in complex subsurface environments, would be partitioning into secondarily formed Fe oxyhydroxides/oxides those are likely to work as a chemical pumps to transport the As in the deeper part of the sediment column in association with vertical infiltration of the groundwater.

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The grains less than 100 nm in seismic slip zones would be generated by mechano-chemical dissolution of fractured grains. The nano grains would behave as lubricant during high speed slip during an earthquake. Large slip weakening would be explained by this mechano-chemical process.

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In Hole B drill cores collected by Taiwan Chelungpu-fault Drilling Project (TCDP), there exist three main fault gouge zones around 1136m, 1194m and 1243m in depth (Hirono et al., 2007), and the 1136m fault gouge zone may have been active in the 1999 Chi-Chi Earthquake (Lin et al., 2008). These fault gouge zones respectively have a black zone with high magnetic susceptibility, which may have been produced due to thermal decomposition of iron-bearing minerals into ferrimagnetic ones by frictional heating (Mishima et al., 2006; Hirono et al., 2007). The inorganic carbon content in the black gouge zones has decreased as compared with the surrounding rocks (Ikehara et al., 2007). This means that carbonate minerals such as calcite in the black gouge zones may have been decomposed by frictional heating. We thus have carried out ESR analysis of the black gouge zones to estimate the degree of frictional heat generation along the Chelungpu fault.Besides the 1194m gouge zone, the black gouge zones show a lower ferrimagnetic resonance (FMR) signal (g=2.1) of maghemite (gamma-Fe2O3), which is produced by thermal dehydration of lepidocrocite (gamma-FeOOH) formed under more oxidative condition, than the surrounding rocks. Step-by-step heating experiments (5 minutes) indicate that the 1136m black gouge zone may have been subjected to heating around 350 degree C at the most, although the temperature depends on the duration of heating. On the other hand, the transformation temperature of maghemite into hematite (alpha-Fe2O3) in a hydrothermal fluid may strikingly decrease (Swaddle & Oltmann, 1980), so that hydrothermal fluids may have passed through the black gouge zone after the production of maghemite. Furthermore, the intensity of Mn2+ ion signal, which is derived from a divalent manganese ion isolated in a crystal such as calcite (CaCO3) under more reductive condition, has been almost annihilated in the black fault zones, whereas Fe3+ ion signal that was isolated in a crystal under more oxidative condition almost remains unchanged in the fault gouge zones. Since calcite can be dissolved in weak acid water containing CO2 (CaCO3+CO2+H2O->Ca2++2HCO3-), the decrease of inorganic carbon content may be subjected to the dissolution of carbonate minerals due to the passing of hydrothermal fluids containing CO2 through the black gouge zones. In this case, Mn2+ ions flowed out of crystals form manganese oxides (MnO) with oxygen ions, and furthermore Mn3O4, which is black and paramagnetic under normal temperature, may be produced by further oxidation during frictional heating. Mn3O4 may be responsible for the blackening of the fault gouge zones with low FMR signal intensity.

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