Swiss Researchers Pioneer Lunar Seismic Monitoring with Fiber Optic Cables
A Swiss research team is developing a novel approach to precisely measure seismic activity within the moon, utilizing kilometer-long fiber optic cables deployed by a small rover. This initiative aims to significantly improve upon existing lunar earthquake data, which primarily stems from the Apollo missions of the 1970s and provides only a limited understanding of the moon’s subsurface.
Limited Data from Apollo Missions
Seismic instruments recorded thousands of moonquakes by 1977, but this dataset offers only a basic understanding of lunar internal activity. Researchers at the Swiss Federal Institute of Technology (ETH) Zurich propose a new method to gain a more precise insight into seismic activities and the structures inside the moon using comparatively simple means as detailed in the journal “Earth Space Science”.
Distributed Acoustic Sensing (DAS) Technology
The core of this project lies in Distributed Acoustic Sensing (DAS) technology. This technique involves sending laser pulses through a fiber optic cable. When seismic waves cause the cable to vibrate, they alter the scattering pattern of the light, which is then recorded by a measuring device. Currently, researchers employ DAS technology on Earth to monitor earthquakes and landslides.
Ideal Conditions on the Moon
According to ETH Zurich, the moon presents an ideal environment for DAS technology due to the absence of an atmosphere and wind, which could otherwise interfere with measurements. Laboratory tests using artificial moon dust have demonstrated that the cables effectively receive signals even when simply lying on the lunar surface, without needing to be buried.
Applications for Future Lunar Missions
Beyond seismic monitoring, the fiber optic cable network could too measure the amount of moon dust ejected by rocket landings. This data is crucial for assessing and mitigating the hazards posed by the extremely fine dust to astronauts on future lunar missions.