Publications
Publications (1st author):
S. Koyama, T. Yoshida, Y. Furukawa, et al. (2024) Stable carbon isotope evolution of formaldehyde on early Mars. Sci Rep 14, 21214. https://doi.org/10.1038/s41598-024-71301-w
S. Koyama, A. Kamada, Y. Furukawa, et al. (2024) Atmospheric formaldehyde production on early Mars leading to a potential formation of bio-important molecules. Sci Rep 14, 2397. https://doi.org/10.1038/s41598-024-52718-9
S. Koyama, N.Terada, H.Nakagawa, et al. (2021) Stability of atmospheric redox states of early Mars inferred from time response of the regulation of H and O losses, The Astrophysical Journal, 912, 135. https://doi.org/10.3847/1538-4357/abf0ac
Publications (Co-author):
T. Yoshida, S. Koyama, Y. Nakamura, N. Terada, K. Kuramoto, Self-Shielding Enhanced Organics Synthesis in an Early Reduced Earth’s Atmosphere, Astrobiology, https://doi.org/10.1089/ast.2024.0048 (2024)
A. Mahieux, S. Viscardy, R.V. Yelle, H. Karyu, S. Chamberlain, S. Robert, A. Piccialli, L. Trompet, J.T. Erwin, S. Ubukata, H. Nakagawa, S. Koyama, R. Maggioloa, N. Pereiraa, G. Cessateura, Y. Willamea, and A. C. Vandaele. Unexpected increase of the deuterium to hydrogen ratio in the Venus mesosphere. Proceedings of the National Academy of Sciences, 121, p.e2401638121, https://doi.org/10.1073/pnas.2401638121 (2024)
S. Aoki, G.L. Villanueva, G. Liuzzi, H. Sagawa, F. Daerden, S. Viscardy, S. Koyama, and A.C. Vandaele, Global mapping of HCl on Mars by IRTF/iSHELL. The Planetary Science Journal, 5, 158, https://doi.org/10.3847/PSJ/ad58dc (2024).
Y. Kawamura, T. Yoshida, N. Terada, Y. Nakamura, S. Koyama, H. Karyu, K. Terada, and S. Sakai, Reduced Water Loss due to Photochemistry on Terrestrial Planets in the Runaway Greenhouse Phase around Pre-main-sequence M Dwarfs. The Astrophysical Journal, 967, 95, https://doi.org/10.3847/1538-4357/ad3e7e (2024)
T. Yoshida, S. Aoki, Y. Ueno, N. Terada, Y. Nakamura, K. Shiobara, N. Yoshida, H. Nakagawa, S. Sakai, and S. Koyama. Strong Depletion of 13C in CO Induced by Photolysis of CO2 in the Martian Atmosphere, Calculated by a Photochemical Model, The Planetary Science Journal 4, 53, https://doi.org/10.3847/PSJ/acc030 (2023)
Y. Nakamura, N. Terada, S. Koyama, T. Yoshida, H. Karyu, K. Terada, T. Kuroda, A. Kamada, I. Murata, S. Sakai, and Y. Suzuki, Photochemical and radiation transport model for extensive use (PROTEUS). Earth Planets Space 75, 140, https://doi.org/10.1186/s40623-023-01881-w (2023).
N. Yoshida, H. Nakagawa, S. Aoki, J. Erwin, A.C. Vandaele, F. Daerden, I. Thomas, L. Trompet, S. Koyama, N. Terada, and L. Neary, Variations in vertical CO/CO2 profiles in the Martian mesosphere and lower thermosphere measured by the ExoMars TGO/NOMAD: Implications of variations in eddy diffusion coefficient. Geophysical Research Letters, 49, p.e2022GL098485, https://doi.org/10.1029/2022GL098485, (2022)
Presentations
International meetings (Oral presentations)
S. Koyama, T. Yoshida, Y. Furukawa, N. Terada, Y. Ueno, Y. Nakamura, A. Kamada, T. Kuroda, and A. C. Vandaele, STABLE CARBON ISOTOPE EVOLUTION OF FORMALDEHYDE AND ITS IMPLICATIONS FOR THE ORIGIN OF EARLY MARS’ ORGANIC MATTER, The Tenth International Conference on Mars, Pasadena, USA, July 2024.
S. Koyama, A. Kamada, Y. Furukawa, N. Terada, Y. Nakamura, T. Yoshida, T. Kuroda, Production of atmospheric formaldehyde on ancient Mars: implications for ribose formation, AbGradEPEC 2023, La Palma, Spain, May 2023.
S. Koyama, N. Terada, H. Nakagawa, T. Kuroda, M. Ogawa, The formation of O2-dominated atmosphere under high EUV flux on early Mars, American Geophysical Union fall meeting, American Geophysical Union, Online, Dec. 2020.
International meetings (Poster presentations)
S. Koyama, T. Yoshida, N. Terada, Y. Furukawa, Y. Nakamura, A. Kamada, T. Kuroda, A. C. Vandaele, Y. Ueno, Stable carbon isotope evolution of formaldehyde and implications for the origin of early Martian organic matter, EGU, May 2024.
S. Koyama, A. Kamada, Y. Furukawa, N. Terada, Y. Nakamura, T. Yoshida, T. Kuroda, Production of atmospheric formaldehyde on ancient Mars: implications for ribose formation, BEACON, La Palma, Spain, May 2023.
S. Koyama, A. Kamada, Y. Furukawa, N. Terada, Y. Nakamura, T. Yoshida, T. Kuroda, Photochemical Production of Formaldehyde in the Early Martian Atmosphere, AGU, Chicago, USA, Dec. 2022.
S. Koyama, N.Terada, H.Nakagawa, T.Kuroda, Stability of atmospheric redox states of early Mars inferred from time response of the regulation of H and O losses, JpGU-AGU Joint Meeting 2020, Online, July 2020.
S. Koyama, N.Terada, H.Nakagawa, T.Kuroda, Stability of atmospheric redox states of early Mars inferred from time response of the regulation of H and O losses, American Geophysical Union fall meeting, San Francisco, USA, Dec. 2019.
S. Koyama, N.Terada, H.Nakagawa, T.Kuroda, Stability of atmospheric redox states of Mars-like planets inferred from time response of the regulation of H and O losses, Planet2/RESCEU symposium 2019, Okinawa, Japan, October 2019.
Domestic meetings (Oral presentations)
(Invited) S. Koyama, T. Yoshida, N. Terada, Y. Furukawa, Y. Nakamura, A. Kamada, T. Kuroda, A. C. Vandaele, Y. Ueno, Atmospheric production of formaldehyde and its carbon isotope evolution on early Mars, JPGU, Chiba, Japan, May 2024.
S. Koyama, T. Yoshida, N. Terada, Y. Furukawa, Y. Nakamura, A. Kamada, T. Kuroda, A. C. Vandaele, Y. Ueno, Stable carbon isotope evolution of formaldehyde on early Mars, Symposium on Planetary Science, Sendai, Sendai, February 2024.
S. Koyama, A. Kamada, Y. Furukawa, N. Terada, Y. Nakamura, T. Yoshida, T. Kuroda, Production of Formaldehyde in the Early Martian Atmosphere, the Japanese Society for Planetary Sciences Fall meeting, Mito, Japan, September 2022.
S. Koyama, N.Terada, K. Terada, H.Nakagawa, T.Kuroda, M. Ogawa, The possibility of O2-dominated Atmosphere Formation under High EUV Flux on Early Mars, the Japanese Society for Planetary Sciences Fall meeting, online, November 2022.
Domestic meetings (Poster presentations)
S. Koyama, T. Yoshida, N. Terada, Y. Furukawa, Y. Nakamura, A. Kamada, T. Kuroda, “Carbon isotope composition of formaldehyde in the early Martian atmosphere inferred from CO2 photolysis”, JSPS Fall meeting, Hiroshima, Japan, October 2023.
S. Koyama, A. Kamada, Y. Furukawa, N. Terada, Y. Nakamura, T. Yoshida, T. Kuroda, Production of Formaldehyde in the Early Martian Atmosphere, Symposium on Planetary Science, Sendai, Japan, February 2023.
S. Koyama, N.Terada, H.Nakagawa, T.Kuroda, Stability of atmospheric redox states of early Mars inferred from time response of the regulation of H and O losses, Joint symposium of graduate schools of science and life sciences, Sendai, Japan, February 2020.
S. Koyama, N.Terada, H. Nakagawa, T. Kuroda, Time response of the self-regulation of H and O escapes from Mars, JPGU, Chiba, Japan, May 2019