A5045053808- Astro and Planetary Science
- Isotope Analysis in Ecology
- Geological and Geochemical Analysis
- Planetary Science and Exploration
- Mass Spectrometry Techniques and Applications
- High-pressure geophysics and materials
- Nuclear Physics and Applications
- Geology and Paleoclimatology Research
- earthquake and tectonic studies
- Paleontology and Stratigraphy of Fossils
- Geochemistry and Geologic Mapping
- Mineralogy and Gemology Studies
- Metabolomics and Mass Spectrometry Studies
- Metallurgy and Cultural Artifacts
- Marine and environmental studies
- Mineral Processing and Grinding
- Ion-surface interactions and analysis
- Ancient and Medieval Archaeology Studies
- Crystal Structures and Properties
- Space Exploration and Technology
- Origins and Evolution of Life
- Chemical Analysis and Environmental Impact
- Molecular Spectroscopy and Structure
- Metal Alloys Wear and Properties
- Astronomical and nuclear sciences
Life Science Institute
2021-2024
Tokyo Institute of Technology
2021-2024
Chiba Institute of Technology
2022-2024
Institut de Planétologie et d'Astrophysique de Grenoble
2019-2022
Earth-Life Science Institute
2022
Centre National de la Recherche Scientifique
2020-2021
Université Grenoble Alpes
2020-2021
Kyushu University
2018
University of California, Los Angeles
2013-2017
Planetary Science Institute
2013-2017
The Hayabusa2 spacecraft collected samples from the surface of carbonaceous near-Earth asteroid (162173) Ryugu and brought them to Earth. were expected contain organic molecules, which record processes that occurred in early Solar System. We analyzed molecules extracted samples. identified a variety containing atoms CHNOS, formed by methylation, hydration, hydroxylation, sulfurization reactions. Amino acids, aliphatic amines, carboxylic polycyclic aromatic hydrocarbons, nitrogen-heterocyclic...
Samples from the carbonaceous asteroid (162173) Ryugu provide information on chemical evolution of organic molecules in early solar system. Here we show element partitioning major component ions by sequential extractions salts, carbonates, and phyllosilicate-bearing fractions to reveal primordial brine composition primitive asteroid. Sodium is dominant electrolyte salt fraction extract. Anions NH4+ are more abundant than carbonate phyllosilicate fractions, with molar concentrations order...
Polycyclic aromatic hydrocarbons (PAHs) contain ≲20% of the carbon in interstellar medium. They are potentially produced circumstellar environments (at temperatures ≳1000 kelvin), by reactions within cold (~10 kelvin) clouds, or processing carbon-rich dust grains. We report isotopic properties PAHs extracted from samples asteroid Ryugu and meteorite Murchison. The doubly-13C substituted compositions (Δ2×13C values) naphthalene, fluoranthene, pyrene 9 to 51‰ higher than values expected for a...
Abstract We report primordial aqueous alteration signatures in water-soluble organic molecules from the carbonaceous asteroid (162173) Ryugu by Hayabusa2 spacecraft of JAXA. Newly identified low-molecular-weight hydroxy acids (HO-R-COOH) and dicarboxylic (HOOC-R-COOH), such as glycolic acid, lactic glyceric oxalic succinic are predominant samples two touchdown locations at Ryugu. The quantitative qualitative profiles for hydrophilic between sampling shows similar trends within order ppb...
Abstract We performed in-situ analysis on a ~ 1 mm-sized grain A0080 returned by the Hayabusa2 spacecraft from near-Earth asteroid (162173) Ryugu to investigate relationship of soluble organic matter (SOM) minerals. Desorption electrospray ionization-high resolution mass spectrometry (DESI-HRMS) imaging mapped more than 200 CHN, CHO, CHO–Na (sodium adducted), and CHNO compounds. A heterogeneous spatial distribution was observed for different compound classes SOM as well among alkylated...
Abstract The sample from the near-Earth carbonaceous asteroid (162173) Ryugu is analyzed in context of meteorites soluble organic matter. analysis molecules samples collected by Hayabusa2 spacecraft shines light on an extremely high molecular diversity C-type asteroid. Sequential solvent extracts increasing polarity are using mass spectrometry with complementary ionization methods and structural information confirmed nuclear magnetic resonance spectroscopy. Here we show a continuum size...
Joegoldsteinite, a new sulfide mineral of end-member formula MnCr2S4, was discovered in the Social Circle IVA iron meteorite. It is thiospinel, Mn analog daubréelite (Fe2+Cr2S4), and member linnaeite group. Tiny grains joegoldsteinite were also identified Indarch EH4 enstatite chondrite. The chemical composition sample determined by electron microprobe (wt%) S 44.3, Cr 36.2, 15.8, Fe 4.5, Ni 0.09, Cu 0.08, total 101.0, giving rise to an empirical (Mn0.82Fe0.23)Cr1.99S3.95. crystal structure,...
Abstract NWA 10214 is an LL 3‐6 breccia containing ~8 vol% clasts including 5, 6, and shocked‐darkened fragments as well matrix‐rich Clast 6 (a new kind of chondrite). This clast a dark‐colored, subrounded, 6.1 × 7.0 mm inclusion, consisting 60 fine‐grained matrix, 32 coarse silicate grains, 8 opaque grains. The large chondrules chondrule are mainly Type IB ; one small IIA . Also present 450 600 μm spinel‐pyroxene‐olivine CAI 85 110 AOI possesses unique set properties. (1) It resembles...
According to several orbital reflectance spectroscopy studies, numerous widely scattered lunar surface locales feature remarkably high (>98%) abundance of plagioclase. These "pure" anorthosite claims are based on an absorption band at ~1.25 μm, associated with minor Fe2+ within But utilization the 1.25 μm as a direct gauge plagioclase requires underlying assumption that FeO is uniform across all measured materials. Available data for in many cases suspect because electron-probe measurements...
Abstract Biologically relevant abiotic extraterrestrial soluble organic matter (SOM) has been widely investigated to study the origin of life and chemical evolution protoplanetary disks. Synthesis biologically organics, in particular, seems require aqueous environments early solar system. However, SOM primitive meteorites includes numerous species besides ones, reaction mechanisms that comprehensively explain complex nature are unknown. Besides, initial reactants, which formed before...
Basaltic rocks occur widely on the terrestrial planets and differentiated asteroids, including asteroid 4 Vesta. We conducted a shock recovery experiment with decaying compressive pulses basalt at Chiba Institute of Technology, Japan. The sample recorded range pressures, physics modeling was to add pressure scale observed features. shocked examined by optical electron microscopy, back-scattered diffractometry, Raman spectroscopy. found that localized melting occurs lower (~10 GPa) than...
Abstract The unique occurrence of abundant (~1 vol%) near‐pure‐Fe metal in the Camel Donga eucrite is more complicated than previously believed. In addition to that component groundmass metal, scattered within meteorite are discrete nodules much higher kamacite abundance. We have studied petrology and composition two these form samples we call CD 2 3. ovoids 11 ( 2) 15 3) mm across, with or inferred preweathering abundances 12–17 vol% unfortunately quite weathered). 3 nodule also includes at...
Amino acids in carbonaceous chondrites may have seeded the origin of life on Earth and possibly elsewhere. Recently, return samples from a C-type asteroid Ryugu were found to contain amino with similar distribution Ivuna-type CI chondrites, suggesting potential acid abundances as molecular descriptors parent body geochemistry. However, chemical mechanisms responsible for distributions remain be elucidated particularly at low temperatures (<50°C). Here, we report that two representative...
Rationale Acquisition quality in analytical science is key to obtaining optimal data from a sample. In very high‐resolution mass spectrometry, driven by the optimization of multiple parameters, including use scans and micro‐scans (or transients) for performing Fourier transformation. Methods Thirty‐nine spectra single synthesized complex sample were acquired using various numbers determined through simple experimental design. An electrospray ionization source coupled with an LTQ Orbitrap XL™...
Abstract Feather features (FFs) in quartz consist of a planar fracture (PF) and associated fine lamellae (FF lamellae; FFL) have been observed various natural impact structures. However, the mechanisms conditions FF formation are poorly understood. We conducted shock recovery experiments on granite using decaying compressive pulses to investigate FFs. characterized recovered samples an optical microscope equipped with universal stage, scanning electron combined back‐scattered diffraction...
Silica polymorphs occur under various pressures and temperature conditions, their characteristics can be used to better understand the complex metamorphic history of planetary materials. Here, we conducted isothermal heating experiments silica in basaltic eucrites assess formation stability. We revealed that each polymorph exhibits different responses: (1) Quartz recrystallizes into cristobalite when heated at ≥ 1040 °C. (2) Monoclinic (MC) tridymite no other ≤ 1070 (3) glass quartz 900-1010...
The chirality of amino acids in extraterrestrial materials may provide an insight into the origin essential l-enantiopure terrestrial biosphere. In 2020, Hayabusa2 mission succeeded bringing back surface from C-type asteroid (162173) Ryugu to Earth. Amino were one targeted organic molecules be studied samples. To analyze various structural isomers acids, which expected present, limited amount returned samples, development a highly-sensitive and selective analytical method was necessary....