A permittivity sensor integrated into melting probes for in-situ cryospheric characterisation

The TRIPLE project aims to develop key technologies for a future space mission dedicated to the search for extraterrestrial life on Jupiter’s moon Europa. The mission concept is based on a melting probe designed to penetrate Europa’s ice shell and deploy scientific instruments into the underlying subsurface ocean to search for life and biosignatures. To validate the feasibility of this approach, the developed technologies are tested stepwise in terrestrial analogue environments under extreme conditions.

Within the TRIPLE-FRS project, a Forefield Reconnaissance System (FRS) for these ice-penetrating melting probes is being developed that combines radar and sonar sensing to scan the probe’s forefield. To enable in-situ correction of radar and sonar wave velocities, an additional sensor is integrated into the melting probe to measure the complex permittivity of the surrounding medium.

This contribution presents the integration of the permittivity sensor into the melting probe TRIPLE-IceCraft, the achievable measurement accuracy for a wide range of dielectrics, and the results of validation experiments conducted in controlled freezer environments and on alpine glaciers. Furthermore, the role of the sensor system within an upcoming Antarctic field campaign at Neumayer Station III during the 2026/2027 season is outlined.