[M-TT38] Brand-new scope of coupling geophysics being established by infrasound and associated waves

[MTT38-10] Investigation of the mechanism of infrasound generation during atmospheric re-entry of Sample Return Capsules (OSIRIS-REx and HAYABUSA series)

*Yuta Hasumi¹, Masa-yuki Yamamoto², Yasuhiro Nishikawa² (1.Graduate school of Engineering Kochi University of Technology, 2.Department of systems engineering, Kochi University of Technology)

Keywords:sample return capsules, Infrasound, HAYABUSA, OSIRIS-REx

Infrasound refers to sound waves with frequencies below 20 Hz, below the lower limit of human audibility (inaudible sound). It is associated with large-scale natural events like volcanic eruptions, earthquakes and tsunamis. This field holds significant potential for disaster prevention applications. One of the natural events expected to be detected by infrasound observation is the atmospheric entry of meteorites. On September 24, 2023, the Sample Return Capsule (SRC) of NASA’s OSIRIS-REx asteroid probe re-entered Earth’s atmosphere at supersonic speed. We considered the SRC that re-entered the atmosphere as an artificial meteor, we conducted infrasound observations. We formed a simple airwave observation network using several portable infrasound sensors and microphones, ew successfully captured infrasonic and sound waves generated by the the SRC. In this study, we focus on observed pressure fluctuations, we aim to understand the mechanisms of shock wave generation associated with different SRCs, such as OSIRIS-REx and Hayabusa2.