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

[PPS01-P11] Toward measurements of elastic wave velocities of laboratory analogs of Titan’s organic materials

*平井 英人^1,2、関根 康人^2,3、辻 健⁴、西澤 修、大内 智博⁵、肥後 祐司⁶ (1.東京工業大学 理学院 地球惑星科学系 地球惑星科学コース、2.東京工業大学 地球生命研究所、3.金沢大学 環日本海域環境研究センター、4.東京大学大学院 工学研究科、5.愛媛大学 地球深部ダイナミクス研究センター、6.(公財)高輝度光科学研究センター)

キーワード：タイタン、探査、ドラゴンフライ、地震波探査、有機物エアロゾル、惑星科学

The seismometer of Dragonfly Geophysics and Meteorology Package (DraGMet) onboarded on NASA’s Dragonfly will measure the seismic activity occurred in Titan. In addition to the passive seismic survey using natural Titan quakes, we will perform the active seismic survey, in which a shaker artificially generates vibrations and wave fields transmitted in shallow subsurface are analyzed. Through the active seismic survey, the shallow subsurface structure down to several to tens meters in depth will be investigated. The shallow subsurface structure includes ice and organic sediments, organic aerosol layer, linear dunes and interdunes, impact structures, and liquid hydrocarbon aquifer. Thereby, the active seismic survey by the DraGMet will first provide geological and geophysical evidence to understand surface processes occurred on Titan. To reveal the detailed subsurface structure, however, the elastic wave velocities of target materials are required. Despite its importance, there are no experimental studies to investigate the elastic wave velocities of laboratory analogs of organic materials on Titan. Here, we will present our methodology development to measure elastic wave velocities of laboratory analogs of Titan’s organic materials at low temperatures. We first generate laboratory analogs of Titan’s organic materials using a radio-frequency generator and low-temperature chamber (Hirai et al., submitted). The small amount of analog material produced makes it challenging to measure its elastic wave velocity at low temperatures. We will present our progress report toward measurements of elastic wave velocities of laboratory analogs.