Researchers from ETH are investigating whether it would be possible to comprehensively monitor the Moon using fiber-optic technology. Thin and lightweight fibers could be deployed on its surface by a lunar rover. According to the university, these cables would function as thousands of small sensors, recording vibrations caused by moonquakes, meteorite impacts, or lunar landings. The research team is led by ETH Professor Johan Robertsson and includes international partners such as the Los Alamos National Laboratory.
The researchers are using Distributed Acoustic Sensing (DAS) technology in their experiments. This involves sending laser light pulses through a fiber-optic cable. Tiny irregularities in the fiber scatter the light, which is then recorded by a measuring device, while seismic waves alter this scattering pattern. The time delay of the signals makes it possible to determine precisely where movement has occurred within the cable network. On Earth, DAS technology is already used to monitor earthquakes and landslides, and even to track whale movements in the oceans.
“Fiber-optic sensing could significantly expand our understanding of the Moon—its internal structure, lava tubes, landing sites, and water resources,” explains Prof. Robertsson. “It has even been suggested that DAS could detect gravitational waves that excite the Moon’s normal modes.” These normal modes, or vibration patterns, are triggered by seismic events such as earthquakes and provide insights into the internal structure of planetary bodies.
For the ETH Zurich team, this research is part of a broader project aimed at developing new sensor technologies.