SELENE-2 Lunar Broadband Seismometer Observation

Abstract

We propose a broadband seismometer system as a payload instrument of the first Japanese landing mission on the moon SELENE-2. In this presentation, we introduce its scientific significance and current state of the development of the seismometer. In the Apollo projects, a triangular seismometer network provided information on the internal structure shallower than a depth of ~1,000 km. It, however, has slightly insufficient sensitivity to detect often occurred deep moonquakes without PEAKED MODE. Moreover, scattering codas in seismic waveforms are generated in the shallow brecciated layer, and masks reflection and converted waves at a structural interface in the moon. To overcome those issues, we propose a broadband seismometer observation. Due to weak coda in long period components, we can obtain information of the lunar deep interior by detecting reflection and converted waves.