Professor Shogo Tachibana of UTOPS and Associate Professor Yoshiko Baba of the Office of Research Strategy and Development (ORSD), Graduate School of Science, UTokyo participated in the session “Frontiers of Research Knowledge with UTokyo URA” at “esse-sense Forum 2024 – Toward Social Implementation of Research Knowledge -” (September 24-25) organized by esse-sense, one of the largest researcher media in Japan.
For details, please refer to the following URL.
Joint Press Release
Shogo Tachibana (Professor, UTOPS, Department of Earth and Planetary Science, ISAS)
An international joint research group led by Deputy Chief Researcher Toshihiro Yoshimura and Senior Researcher Yoshinori Takano of the Japan Agency for Marine-Earth Science and Technology, Chief Researcher Daisuke Araoka of the National Institute of Advanced Industrial Science and Technology, and Professor Hiroshi Naraoka of the Graduate School of Science, Kyushu University, together with researchers from the University of Tokyo, Horiba Techno Service, Hokkaido University, Tokyo Institute of Technology, and Tokai National University Organization Nagoya University, have conducted an international joint research project on the asteroid Ryugu. Precise chemical analyses of magnesian minerals such as breunnerite and primitive brines in samples from the asteroid Ryugu revealed their composition and content.
Asteroid Ryugu is one of the most primitive bodies that retain the chemical composition of the entire solar system before the birth of the Earth. Although analyses by various research groups have revealed aqueous metamorphism involving minerals, organic matter, and water, the reaction history of the so-called “brine chemical composition and precipitation of ionic components” has remained unknown.
In this study, we isolated and identified small carbonate minerals (breunnerite) from samples from the asteroid Ryugu, extracted the cationic components with solvents, and performed precise chemical composition analysis. As a result, the cation composition of the last water in contact with the minerals in Ryugu was found to be rich in sodium ions (Na+). There are several minerals in Ryuguu that are very rich in magnesium, which elucidated the precipitation order of magnesium removal from the water. Sodium ions may have acted as electrolytes that stabilized the surface charges of minerals and organic materials.
This achievement is an important finding that unravels the chemical evolution of the early solar system and provides primary information on primordial brine material and water-mineral interactions on carbonaceous asteroids.
The results were published in the scientific journal Nature Communications on September 5, 2024 (JST).
For more information, please refer to the following
Graduate School of Science web: https://www.s.u-tokyo.ac.jp/en/press/10478/
Publication URL: https://www.nature.com/articles/s41467-024-50814-y
UTokyo Organization for Planetary Space Science (UTOPS) and Department of Earth and Planetary Science cooperated in the “Asteroid Itokawa and Ryugu Double Sample Exhibition in Nagoya City Science Museum” held from August 6 (Tue) to August 25 (Sun), 2024, at the 5th floor demo space of the Nagoya City Science Museum’s Astronomy Building.
Samples from the asteroid Itokawa, brought back to Earth by the asteroid explorer Hayabusa in June 2010, and samples from the asteroid Ryugu, brought back to Earth by the asteroid explorer Hayabusa2 in December 2020, were displayed side by side.
For details, please refer to the following URL.
https://www.ncsm.city.nagoya.jp/visit/attraction/event/2024/itokawa_ryuugu.html
On August 5 (Mon.) and 6 (Tue.), 2024, we held an astronomy training for students from Kariya High School in Aichi Prefecture and Matsumoto-Fukashi High School in Nagano Prefecture. The students observed a sample of Ryugu and took a class about results of Hayabusa2 mission. They estimated the distance to galaxies from photographs of galaxies and used the recession speeds of these galaxies to determine the age of the universe.
On Friday, August 2, 2024, students from Komatsu High School in Ishikawa, Japan, visited UTOPS. We gave them a mock lecture about the Hayabusa2 exploration and the rock brought back from the asteroid Ryugu, and showed them around our laboratory.
The nano-satellites developed by our laboratory so far and the future of Japanese space development will be introduced on BS Teleto’s “Imakara Science,” which will be broadcast from 10:00 p.m. on the evening of the 17th today. Professor Shinichi Nakasuka will also appear on the program. Please watch the program!
URL : https://t.co/UdEcUs6Ynw
Joint Press Release
Shogo Tachibana (Professor, UTOPS, Department of Earth and Planetary Science, ISAS)
An international research group led by Senior Scientist Yoshinori Takano of the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Professor Hiroshi Naraoka of Kyushu University, and Principal Investigator Jason Dworkin of the National Aeronautics and Space Administration (NASA), along with researchers from Keio University, Human Metabolome Technologies, Hokkaido University, Tohoku University, Hiroshima University, Nagoya University, Kyoto University, the University of Tokyo, extracted soluble components in samples from the asteroid Ryugu and performed precise chemical analysis. A total of 84 diverse organic acids (including newly discovered monocarboxylic, dicarboxylic, tricarboxylic, and hydroxy acids) and nitrogen-containing compounds with a high affinity for water were identified, providing conclusive evidence for the current state of chemical evolution and water quality metamorphism (Figure). These include oxalic acid, citric acid, malic acid, pyruvic acid, pyruvic acid, lactic acid, mevalonic acid, and others, as well as a group of alkylurea molecules, an organic-inorganic complex, revealing the origin of chemical evolution dominated only by physical and chemical factors. We then summarized the light element composition (carbon, nitrogen, hydrogen, oxygen, and sulfur) and organic material science properties, including stable isotope composition, molecular composition, and content, of the organic matter at the two touchdown sampling sites.
These results provide primary information on the chemical evolution of the early solar system and are important for understanding the larger scientific inquiry into how non-living organic molecules led to the evolutionary processes that ultimately led to the emergence of life.
This research was supported by Grant-in-Aid for Scientific Research on Innovative Areas (Grant-in-Aid for International Cooperative Research Enhancement, Project No. 21KK0062), the Institute of Low Temperature Science, Hokkaido University Joint Project, and other research grants.
The results were published in the scientific journal Nature Communications on July 10, 2024 (18:00 JST).
Asteroid Ryugu was once a parent body rich in water (H2O) and has been repeatedly frozen/thawed during its evolution in the solar system. By analyzing soluble components with high precision, we found conclusive evidence of “aqueous alteration” recorded in hydrophilic organic molecules. A total of 84 new species (including structural isomers) of organic acids (65 newly identified species including oxalic acid, malonic acid, citric acid, malic acid, pyruvic acid, lactic acid, and mevalonic acid) and nitrogen-containing molecules (19 new organic-inorganic complexes including alkylureas) with high affinity to water were discovered. It is believed that the primary molecular evolution involving water-organic-mineral interactions is still underway.
For more information, please refer to the following
Graduate School of Science web: https://www.s.u-tokyo.ac.jp/en/press/10423/
Publication URL: https://www.nature.com/articles/s41467-024-49237-6
Professor Nicolas Dauphas, Department of the Geophysical Sciences, University of Chicago, visited UTOPS and gave a lecture “The origin and evolution of the Moon” from a cosmochemical perspective.
(2024.6.26)
