[P-PS01] Outer Solar System Exploration Today, and Tomorrow

[PPS01-03] Titan Seismology with DraGMetSEIS

*Taichi Kawamura¹, Hiroaki Shiraishi², Satoshi Tanaka², Takefumi Mitani², Keisuke Onodera³, Hideki Murakami⁴, Ryuhei Yamada⁷, Shunichi Kamata⁸, Jun Kimura⁹, Hiroyuki Kurokawa¹⁰, Kiwamu Nishida³, Yasuhito Sekine¹¹, Takeshi Tsuji¹⁰, Mark Panning⁶, Ralph Lorenz⁵, Sébastien Rodriguez¹, Antoine Lucas¹ (1.Universite Paris Cite Institut de physique du globe de Paris CNRS, 2.ISAS/JAXA, 3.Earthquake Research Institute / The University of Tokyo, 4.Kochi University, 5.Applied Physics Laboratory Johns Hopkins University, 6.Jet Propulsion Laboratory, California Institute of Technology, 7.The University of Aizu, Revitalization and Creation Support Center, 8.Faculty of Science, Hokkaido University, 9.Osaka University, 10.The University of Tokyo, 11.Earth-Life Science Insitute, Tokyo Institute of Technology)

Keywords:Planetary Science, Titan, Seismology

Dragonfly was selected as the 4th New Frontier Mission to explore Titan and investigate its astrobiological potential. Among the suite of instruments on board, the Dragonfly Geophysics and Meteorology Package (DraGMet) is equipped with various geophysical and meteorological sensors to investigate the Titan’s surface and subsurface environment including a vertical short period seismometer and two 2-axes geophone package on its skids. ISAS/JAXA has been developing the short period seismometer for the spacecraft and we will introduce some tests and current expectations for its performances. The instrument will be performing the first seismic observation in the icy world and there are huge uncertainties in its seismicity as well as the noise environment. To be well prepared for the observation, we describe here our approach to evaluate the seismic signal and the noise that we expect on Titan. We mainly focus here on atmospheric signals expected for Titan. We take a similar approach as that for InSight. InSight took numerical models of Mars such as Global Circulation Model (GCM) or Large Eddy Simulation (LES) as inputs and evaluated the ground response. This will enable us to evaluate the expected ambient noise as well as transient seismic events from atmosphere. While atmospheric activities act as a significant source of noise, some transient events such as pressure drops can be detected with seismometer and then be used to study subsurface structure and it would be important to have quantitative evaluation on their detectability. We would also discuss some other possible source that were pointed out in previous studies We compare such signals with known instrumental noise and obtained environmental noise to discuss their detectability.