Influx of nitrogen-rich material from the outer Solar System indicated by iron nitride in Ryugu samples

Matsumoto, T. et al. (2023) Influx of nitrogen-rich material from the outer Solar System indicated by iron nitride in Ryugu samples. Nature Astronomy, (doi: 10.1038/s41550-023-02137-z) (Early Online Publication)

Abstract

Large amounts of nitrogen compounds, such as ammonium salts, may be stored in icy bodies and comets, but the transport of these nitrogen-bearing solids into the near-Earth region is not well understood. Here, we report the discovery of iron nitride on magnetite grains from the surface of the near-Earth C-type carbonaceous asteroid Ryugu, suggesting inorganic nitrogen fixation. Micrometeoroid impacts and solar wind irradiation may have caused the selective loss of volatile species from major iron-bearing minerals to form the metallic iron. Iron nitride is a product of nitridation of the iron metal by impacts of micrometeoroids that have higher nitrogen contents than the CI chondrites. The impactors are probably primitive materials with origins in the nitrogen-rich reservoirs in the outer Solar System. Our observation implies that the amount of nitrogen available for planetary formation and prebiotic reactions in the inner Solar System is greater than previously recognized.

• Item Type: Articles
• Additional Information: This work was funded by the Japan Society for the Promotion of Science (KAKENHI Grant Nos. 21K113981, 21H05431, 19H0094, 19KK0094, 21H05424, 20H00198, 20H00205 and 20K14537).
• Status: Early Online Publication
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Daly, Dr Luke and Lee, Professor Martin
• Authors: Matsumoto, T., Noguchi, T., Miyake, A., Igami, Y., Haruta, M., Seto, Y., Miyahara, M., Tomioka, N., Saito, H., Hata, S., Harries, D., Takigawa, A., Nakauchi, Y., Tachibana, S., Nakamura, T., Matsumoto, M., Ishii, H. A., Bradley, J. P., Ohtaki, K., Dobrică, E., Leroux, H., Le Guillou, C., Jacob, D., de la Peña, F., Laforet, S., Marinova, M., Langenhorst, F., Beck, P., Phan, T. H.V., Rebois, R., Abreu, N. M., Gray, J., Zega, T., Zanetta, P.-M., Thompson, M. S., Stroud, R., Burgess, K., Cymes, B. A., Bridges, J. C., Hicks, L., Lee, M. R., Daly, L., Bland, P. A., Zolensky, M. E., Frank, D. R., Martinez, J., Tsuchiyama, A., Yasutake, M., Matsuno, J., Okumura, S., Mitsukawa, I., Uesugi, K., Uesugi, M., Takeuchi, A., Sun, M., Enju, S., Michikami, T., Yurimoto, H., Okazaki, R., Yabuta, H., Naraoka, H., Sakamoto, K., Yada, T., Nishimura, M., Nakato, A., Miyazaki, A., Yogata, K., Abe, M., Okada, T., Usui, T., Yoshikawa, M., Saiki, T., Tanaka, S., Terui, F., Nakazawa, S., Watanabe, S.-i., and Tsuda, Y.
• College/School: College of Science and Engineering > School of Geographical and Earth Sciences
• Journal Name: Nature Astronomy
• Publisher: Nature Research
• ISSN: 2397-3366
• ISSN (Online): 2397-3366
• Copyright Holders: Copyright: © The Author(s) 2023
• First Published: First published in Nature Astronomy 2023
• Publisher Policy: Reproduced under a Creative Commons licence