EGU23-1968
https://doi.org/10.5194/egusphere-egu23-1968
EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Hisaki space telescope observations of the large oscillations of Martian hydrogen and oxygen upper atmospheres

Kei Masunaga1, Naoki Terada2, Nao Yoshida2, Yuki Nakamura2,3, Takeshi Kuroda2,4, Kazuo Yoshioka5,6, Yudai Suzuki6, Hiromu Nakagawa2, Tomoki Kimura7, Fuminori Tsuchiya8, Go Murakami1, Atsushi Yamazaki1, Tomohiro Usui1, and Ichiro Yoshikawa5,6
Kei Masunaga et al.
  • 1Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan (masunaga.kei@jaxa.jp)
  • 2Department of Geophysics, Graduate School of Science, Tohoku University, Sendai, Japan
  • 3LATMOS, Sorbonne Universite, Paris, France
  • 4Division for the Establishment of Frontier Science of Organization for Advanced Studies, Tohoku University, Sendai, Japan
  • 5Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan
  • 6Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Tokyo, Japan
  • 7Faculty of Science, Tokyo University of Science, Tokyo, Japan
  • 8Planetary Plasma and Atmospheric Research Center, Graduate School of Science, Tohoku University, Sendai, Japan

Analyzing extreme ultraviolet spectra of the Martian upper atmosphere obtained from the Hisaki space telescope, we found anti-correlation between hydrogen (HI Ly-β) and oxygen (OI 1356 Å and OI 1304 Å) airglow brightness during one of the major regional dust storms in Mars Year 33 (Masunaga et al., 2022). Ly-β brightness gradually increased by a factor of 2 over the observation period (LS=213°–232°) while oxygen airglow temporarily decreased by a factor of 3 during the dust storm period. We also found that their brightness varied alternately with a periodicity of ~6–8 days. The magnitude of their periodic airglow variations was ~20–50% for the whole disk, and the periodicity was consistent with that of atmospheric waves observed by the Curiosity Rover on the surface of Mars. These results suggest that hydrogen and oxygen abundances in the Martian upper atmosphere are highly controlled by dust- and wave-couplings between the lower and upper atmosphere, possibly altering the efficiency of hydrogen and oxygen escape from Mars.

 

Reference

Masunaga, K., N. Terada, N. Yoshida, Y. Nakamura, T. Kuroda, K. Yoshioka, Y. Suzuki, H. Nakagawa, T. Kimura, F. Tsuchiya, G. Murakami, A. Yamazaki, T. Usui, and I. Yoshikawa, Alternate oscillations of Martian hydrogen and oxygen upper atmospheres during a major dust storm, Nature Communications, 13, 6609, 2022

How to cite: Masunaga, K., Terada, N., Yoshida, N., Nakamura, Y., Kuroda, T., Yoshioka, K., Suzuki, Y., Nakagawa, H., Kimura, T., Tsuchiya, F., Murakami, G., Yamazaki, A., Usui, T., and Yoshikawa, I.: Hisaki space telescope observations of the large oscillations of Martian hydrogen and oxygen upper atmospheres, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-1968, https://doi.org/10.5194/egusphere-egu23-1968, 2023.