WHAT'S NEW
February 2022. A Hayabusa-2 sample paper published in Science [Link][ISAS/JAXA press release (EN)] [ISAS/JAXA press release (Jp)]
December 2021. Two Hayabusa-2 sample papers published in Nature Astronomy [Link] [Link] [ISAS/JAXA press release (EN)] [ISAS/JAXA press release (EN)]
December 2021. Appears on the TBS radio to talk about Hayabusa 2 (in Japanese) [Link] [podcast]
December 2021. A book published online (in Japanese) "火星の歩き方", 光文社新書. [Link]
August 2021. A paper published online (Hyodo & Usui, Science) [Link]: Searching for life on Mars and its moons [ISAS/JAXA press release (EN)] [ISAS/JAXA press release (Jp)]
SELECTED PUBLICATIONS [complete publication list]
Mars water & habitability
Hyodo R. and Usui, T. (2021) Searching for life on Mars and its moons. Science. 373, 742. [Link] [ISAS/JAXA press relase (EN)] [ISAS/JAXA press relase (Jp)]
Koike, M., Nakada, R., Kajitani, I., Usui, T.., Tamenori, Y., Sugahara, H., Kobayashi, A. (2020) In-situ preservation of nitrogen-bearing organics in Noachian Martian carbonates. Nature Communications, 11, 1988. doi.org/10.1038/s41467-020-15931-4 [Open Access] [EurekAlert] [msn.com] [space.com] [science alert]
Ramirez, R. M, Craddock, R. A., and Usui, T. (2020) Climate simulation of early Mars with estimated precipitation, runoff, and erosion rates. Journal of Geophysical Research–Planets, doi:10.1029/2019JE006160. [Link]
Kurokawa, H., Kurosawa, K. and Usui, T. (2018) A lower limit of atmospheric pressure on early Mars inferred from nitrogen and argon isotopic compositions. Icarus, 299, 443-459 [Link]
Usui, T. (2017) Martian water stored underground. Nature, 552, 339-340. [Link]
Ehlmann, B. L. et al. (incl. Usui, T.) (2016) The sustainability of habitability on terrestrial planets: insights, questions, and needed measurements from Mars for understanding the evolution of Earth-like worlds. Journal of Geophysical Research-Planets, 121, DOI: 10.1002/2016JE005134. [Open Access] [Top-10 most downloaded paper in 2016-2017 JGR]
Kurokawa, H., Usui, T. and Sato, M. (2016) Interactive evolution of multiple water-ice reservoirs on Mars: Insight from hydrogen isotope compositions. Geochemical Journal, 50, 67–79. DOI:10.2343/geochemj.2.0407.
Usui T., Alexander C. M.O'D., Wang J., Simon J. I., and Jones J. H. (2015) Meteoritic evidence for a previously unrecognized hydrogen reservoir on Mars. Earth and Planetary Science Letters 410, 140-151. [Top-rated article in EPSL] [NASA press release]
Kurokawa H., Sato M., Ushioda M., Matsuyama T., Moriwaki R. Dohm, J. M., and Usui, T. (2014) Evolution of Water Reservoirs on Mars: Constraints from Hydrogen Isotopes in Martian Meteorites. Earth and Planetary Science Letters 394, 179-185.
Usui T., Alexander C. M.O'D., Wang J., Simon J. I., and Jones J. H. (2012) Origin of water and mantle–crust interactions on Mars inferred from hydrogen isotopes and volatile element abundances of olivine-hosted melt inclusions of primitive shergottites. Earth and Planetary Science Letters 357-358, 119-129. [NASA press release]
Earth's water circulation
Kurokawa, H., Foriel, J., Laneuville, M., Houser, C., and Usui, T. (2018) Subduction and atmospheric escape of Earth's seawater constrained by hydrogen isotopes, Earth and Planetary Science Letters 497, 149-160 [Link]
Usui T., Kobayashi K., Nakamura E., and Helmstaedt H. (2007). Trace element fractionation in deep subduction zones inferred from a lawsonite-eclogite xenolith from the Colorado Plateau. Chemical Geology 239, 336-351.
Usui T., Nakamura E., and Helmstaedt H. (2006). Petrology and geochemistry of eclogite xenoliths from the Colorado Plateau: Implications for the evolution of the subducted oceanic crust. Journal of Petrology 47, 929–964.
Usui T., Nakamura E., Kobayashi K., Maruyama S., and H. Helmstaedt (2003). Fate of the subducted Farallon plate inferred from eclogite xenoliths in the Colorado Plateau. Geology 30, 589-592.
Terrestrial magmatisms & differentiation
Nakada, R., Usui, T., Ushioda, M., Takahashi, Y. (2020) Vanadium micro-XANES determination of oxygen fugacity in olivine-hosted glass inclusion and groundmass glasses of martian primitive basalt Yamato 980459. American Mineralogist. 105, 1695–1703. [Link]
Moriwaki, R., Usui, T., Tobita, M. and Yokoyama T. (2020) Geochemically heterogeneous Martian mantle inferred from Pb isotope systematics of depleted shergottites, Geochim. Cosmochim. Acta, 274, 157-171. DOI:10.1016/j.gca.2020.01.014. [Link]
Moriwaki, R., Usui, T., Simon, J.I., Jones, J.H., Yokoyama, T. and Tobita, M. (2017) Coupled Pb isotopic and trace element systematics of Tissint meteorite: geochemical signatures of the depleted shergottite source mantle. Earth and Planetary Science Letters, 474, 180-189. [Link]
Peters, T. J., Simon, J. I., Jones, J. H., Usui, T., Moriwaki, R., Economos, R. C., Schmitt, A. K., and McKeegan, K. D. (2015) Tracking the source of the enriched martian meteorites in olivine-hosted melt inclusions of two depleted shergottites, Yamato 980459 and Tissint. Earth and Planetary Science Letters 418, 91–102.
Usui T., Sanborn M., Wadhwa M., and McSween H. Y. (2010). Petrology and trace element geochemistry of Robert Massif 04261 and 04262 meteorites, the first examples of geochemically enriched lherzolitic shergottites. Geochimica et Cosmochimica Acta 74, 7283-7306.
Usui T., McSween H. Y., and Clark B. C. III. (2008). Petrogenesis of high-phosphorous Wishstone-class rocks in Gusev crater, Mars. Journal of Geophysical Research–Planets 113, E12S44, doi:10.1029/2008JE003225.
Usui T., McSween H. Y., and Floss C. (2008). Petrogenesis of olivine-phyric shergottite Yamato-980459, revisited. Geochimica et Cosmochimica Acta 72, 1711-1730.
DAWN & asteroid
Usui T., Jones J. H., and Mittlefehldt D. W. (2015) A partial melting study of an ordinary (H) chondrite composition with application to the unique achondrite Graves Nunataks 06128 and 06129. Meteoritics & Planetary Science 50, 759-781.
Usui, T. and Iwamori, H. (2013) Mixing relations of the howardite-eucrite-diogenite suite: a new statistical approach of independent component analysis for the Dawn mission. Meteoritics & Planetary Science 48, 2289-2299.
Usui T., McSween H. Y., Mittlefehldt D. W., and Prettyman T. H. (2010). K-Th-Ti systematics and new three-component mixing model of HED meteorites: Prospective study for interpretation of gamma-ray and neutron spectra for the Dawn mission. Meteoritics & Planetary Science 45, 1170-1190.
Usui T. and McSween H. Y. (2007). Geochemistry of 4 Vesta based on HED meteorites: Prospective study for interpretation of gamma ray and neutron spectra for the Dawn mission. Meteoritics & Planetary Science 42, 269–283.