北海道大学 · 물리·천문학
히사요시 유리모토 교수의 연구실은 태양계의 초기 물질, 특히 극히 나이가 많고 변하지 않은 근원성 천체 물질의 산화물과 동위원소 조성을 중심으로 연구를 진행합니다. 주로 극한의 산소 동위원소 비율 변화가 나타나는 우주 물체, 예를 들어 퇴적성 흑색 편석우주석, 태양계 형성 초기의 칼슘알루미늄 포함체(CAI), 그리고 소행성 Ryugu와 Itokawa의 표면 물질을 분석하여 태양계 형성 과정에서의 물질 이동과 화학적 변화를 규명하고자 합니다. 특히, 태양계 내부에서의 산소 동위원소 분馏, 얼음 먼지의 운반, 수소 및 산소 동위원소의 비정상적 분포 메커니즘을 중심으로 기초 천체물리학과 천체화학의 융합 연구를 수행하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Meteorites and their components have anomalous oxygen isotopic compositions characterized by large variations in 18O/16O and 17O/16O ratios. On the basis of recent observations of star-forming regions and models of accreting protoplanetary disks, we suggest that these variations may originate in a parent molecular cloud by ultraviolet photodissociation processes. Materials with anomalous isotopic compositions were then transported into the solar nebula by icy dust grains during the collapse of t
Carbonaceous meteorites are thought to be fragments of C-type (carbonaceous) asteroids. Samples of the C-type asteroid (162173) Ryugu were retrieved by the Hayabusa2 spacecraft. We measured the mineralogy and bulk chemical and isotopic compositions of Ryugu samples. The samples are mainly composed of materials similar to those of carbonaceous chondrite meteorites, particularly the CI (Ivuna-type) group. The samples consist predominantly of minerals formed in aqueous fluid on a parent planetesima
Oxygen isotopic composition of our solar system is believed to have resulted from mixing of two isotopically distinct nebular reservoirs, 16O-rich and (17,18)O-rich relative to Earth. The nature and composition of the (17,18)O-rich reservoir are poorly constrained. We report an in situ discovery of a chemically and isotopically unique material distributed ubiquitously in fine-grained matrix of a primitive carbonaceous chondrite Acfer 094. This material formed by oxidation of Fe,Ni-metal and sulf
Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relativ
Research Article| January 01, 2008 Oxygen Isotopes of Chondritic Components Hisayoshi Yurimoto; Hisayoshi Yurimoto Department of Natural History Sciences, Isotope Imaging Laboratory of CRIS, Hokkaido University, Sapporo 060-0810, Japan, yuri@ep.sci.hokudai.ac.jp Search for other works by this author on: GSW Google Scholar Alexander N. Krot; Alexander N. Krot Hawai'i Institute of Geophysics and Planetology, School of Ocean and Earth Science and Technology, University of Hawai'i at Manoa, Honolulu
A calcium-aluminum-rich inclusion (CAI) from the Allende meteorite was analyzed and found to contain melilite crystals with extreme oxygen-isotope composition (approximately 5 percent oxygen-16 enrichment relative to terrestrial oxygen-16). Some of the melilite is also anomalously enriched in oxygen-16 compared with oxygen isotopes measured in other CAIs. The oxygen isotopic variation measured among the minerals (melilite, spinel, and fassaite) indicates that crystallization of the CAI started f
