The Moon has no atmosphere, no ocean, and no excuse for all that seismic noise Earth deals with. That is a feature. Researchers at Los Alamos National Laboratory and ETH Zurich have published two peer-reviewed studies showing that fiber-optic cables laid directly on the lunar surface could detect moonquakes with enough fidelity to map the Moon's interior structure, locate lava tubes, and prospect for water ice. Their work appears in Earth and Space Science and Icarus.
The technology is Distributed Acoustic Sensing, or DAS. Send laser pulses through standard telecom fiber and tiny imperfections in the glass scatter light back to an interrogator. That backscatter is readable as vibration data at every point along the cable simultaneously, turning a single fiber into thousands of sensors. Los Alamos physicist Carly Donahue, corresponding author on both papers, put it simply: standard fiber is lightweight, robust, and inexpensive, and the Moon doesn't have wind.
That matters more than it sounds. On Earth, DAS requires burial because even modest wind speeds shake surface fiber and swamp the signal. The Moon has a thin exosphere, essentially vacuum with a few scattered molecules. Surface-draped fiber on the lunar mare is effectively quiet. The ETH Zurich team demonstrated in controlled tests that burial depth in simulated lunar regolith made no significant difference to signal clarity, according to Los Alamos.
Apollo's seismometers, deployed between 1969 and 1977, detected over 12,000 seismic events from a network of four stations, as Universe Today reported. A 2024 reanalysis of the same Apollo data identified roughly 22,000 previously uncatalogued events, nearly tripling the count. The point stands either way: four stations in eight years produced a sparse dataset that geologists have been arguing over for decades. A fiber array deployed along a surface traverse could sample ground motion at meter-scale intervals across tens of kilometers, orders of magnitude more data than Apollo returned in its entire operational life. Moonquakes don't just rumble differently than earthquakes. They last longer because there's nothing to absorb the energy. "The Moon doesn't dissipate energy well," Donahue noted. "It takes a very long time for the seismicity to die down."
The Icarus paper tested which cable designs work best on the surface. Stiffer, thicker cable with continuous ground contact produces stronger signals, but thickness adds weight, always the constraint on any lunar mission. A cable hundreds of meters long could characterize thermal moonquakes, the kind driven by extreme temperature swings as the lunar night drops below minus-200 degrees Fahrenheit and the day climbs above 200 degrees. Cables exceeding 10 kilometers would enable deep interior studies, probing the core-mantle boundary.
The ETH Zurich work was led by Simone Probst, a doctoral researcher in the applied geophysics group run by Johan Robertsson. Their modeling showed fiber arrays could detect lava tubes, map subsurface structures, and help identify water deposits near the poles, the kind of information Artemis crews will need for sustained surface operations, as ETH Zurich reported.
There's a complication nobody has tested in situ. When a rocket lands on the Moon, the lack of atmosphere means particles blast off the surface at roughly 2 kilometers per second. That sandblasting effect can travel far from the landing site and damage equipment or fiber at distance. The papers acknowledge this; it's an engineering problem that flight demonstrations would have to solve.
The economics are worth noting. Traditional seismometers run $10,000 to $100,000 per unit, according to Earth Magazine, and that cost accumulates fast when you need coverage. A fiber array distributes sensing points across however long a cable you deploy, turning one interrogator and a spool of commercial fiber into tens of thousands of sensors. The interrogator units are compact; the cables are off-the-shelf telecom hardware. The expense is in getting a mission selected that carries it as part of its science payload, and no such mission exists yet. DAS makes coverage cheap enough to actually try. The question is when someone decides to try.
