Current Developments in the Forefield Reconnaissance System for Melting Probes for the Exploration of Subglacial Lakes with the TRIPLE Project

In search of extraterrestrial life within the solar system, Jupiter’s moon Europa emerges as a promising candidate. Previous observations indicate the existence of a global ocean beneath the moon’s icy shell. To explore the hidden water reservoir, future missions need to penetrate the kilometer-thick ice layer. Within the project line TRIPLE (Technologies for Rapid Ice Penetration and subglacial Lake Exploration), initiated by the German Space Agency at DLR, technologies for such a mission are under development.
Three main components are involved: (i) A retrievable electrothermal drill, also referred to as a melting probe, for penetrating the ice shell and investigating the ice layer. (ii) A miniaturized autonomous underwater vehicle (nanoAUV) for exploring the water reservoir and collecting samples. (iii) An astrobiological laboratory for in-situ examination of samples.

For the melting probe to be able to detect obstacles on its trajectory, safely navigate to the ice-water interface and anchor itself there, it needs a robust forefield reconnaissance system. In this contribution, we present a hybrid forefield reconnaissance system (FRS) that combines sonar and radar. This hybrid approach was selected to utilize the complementary advantages of both sensor systems. Both radar and sonar will be integrated into the melting head. To determine the propagation speed of the electromagnetic waves and to further provide scientific data about the ice stratification, a permittivity sensor is included.

The entire TRIPLE system is to demonstrate its operational capability in an analog terrestrial scenario in the Antarctic. Of particular interest is the Dome C region, as it is expected that subglacial lakes in this area lie beneath a several-kilometer-thick ice shell. The next milestone for addressing this challenge is an intermediate test on the Ekström Ice Shelf. Although the introduced FRS concept was successfully tested on Alpine glaciers, adaptations will be necessary for its integration into the full TRIPLE scenario. In this presentation, we will present the latest developments related to the upcoming campaign.