The ROBEX Lunar Analogue Mission on Mt. Etna, Sicily

Kurzfassung

The joint development of exploration technologies for highly inaccessible terrains has been central to the Helmholtz Alliance "Robotic Exploration of Extreme Environments" (ROBEX). Within its nominal five-year funding period, an intensive exchange between Germany's Helmholtz centers for space, marine, and polar research, universities and industrial partners has been accomplished. In summer 2017, technology demonstrations were conducted in the Arctic Sea (Expedition PS108 of R/V "Polarstern") and on Mt. Etna, Sicily, the latter aimed at the future installation of an active lunar seismic network (ASN). The partly autonomous experiment scenario consists of a lander, rover and payload boxes, termed "remote units". A seismometer network was used for reference, and the technological goal was to demonstrate the recording of seismic data in scientific quality. In cooperation with Parco dell'Etna and INGV Catania, the field site for the demonstration mission was chosen based on geological and geophysical reasoning. First scouting activities in 2015 revealed similarities between regolith-covered mare regions on the Moon and the Piano del Lago plain on the southern flank of Mt. Etna. Therefore, the latter was considered as lunar analogue test site in terms of expected scientific gain, communication infrastructure, and accessibility. Basaltic lava flows covered by thick tephra layers were deposited during the 2001 flank eruption when the Laghetto ash cone formed. Evaluation of the recorded seismograms revealed that the uppermost, about 10-meter thick layer is composed of material with a very low P-wave velocity and underlain by more consolidated materials with a much higher velocity. Both thickness and velocities are compatible with previous geological studies. In parallel, the annual ROBEX International Summer School for Planetary and Ocean Exploration was held on Vulcano, Sicily, combining lectures and extensive field training for graduate students (MSc, PhD), and using geophysical and oceanographic sensor-packages and robots inside Grand Cratere, Vulcano, and in the coastal waters around.