Seismic Detectability of a Subsurface Ocean on Europa

Abstract A seismometer placed on Jupiter's moon Europa can use passive monitoring to determine the presence or absence of a possible liquid water ocean beneath Europa's surface ice and estimates of the thickness of the ice shell itself. Using probable seismic velocities for Europa's ice it is demonstrated that surface waves propagating in the frequency band of 0.1 to 0.5 Hz (wave periods of 2 to 10 s) can discriminate ice shells varying from 5 to 20 km in thickness. Miniature, light-weight seismometers with appropriate sensitivities are available.

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