Water buried beneath the moon may be detectable by listening to how vibrations move through the lunar ground.
Researchers from the University of Maryland, Lawrence Berkeley National Laboratory and the University of Hawaii have found that seismic waves, the same type of vibrations scientists measure during earthquakes, could help locate and map ice hidden below the moon's surface.
Lunar Ice Could Support Future Moon Missions
The findings were published in Science Advances on July 31, 2026, as space agencies prepare for a new era of lunar exploration. NASA's Artemis program is aiming for crewed missions to the moon's south polar region in 2028, where permanently shadowed craters may contain valuable deposits of water ice.
For astronauts, that ice could serve several purposes. Once melted and purified, it could provide drinking water. Electricity could also separate it into oxygen for breathing and hydrogen for rocket fuel. A reliable local supply would reduce the amount of material that future missions need to transport from Earth.
"It's crucial to identify any materials on the moon that an astronaut can make use of while they're up there," said Nicholas Schmerr, an associate professor in UMD's Department of Geological, Environmental, and Planetary Sciences and a co-author of the study. "Since they will be limited by the few resources they brought from Earth, anything they find on the moon will help them basically live off the land, especially for longer-term missions or outposts."
Satellites Cannot See Deep Underground
Scientists still do not know exactly how much ice exists on the moon or where most of it is located. Orbiting satellites can examine the lunar surface, but their instruments mainly detect material in the uppermost layer of soil.
Some of the moon's water ice may be buried much farther below the surface. The new study suggests that seismic measurements could reveal deposits that orbital observations cannot reach.
Frozen and dry lunar soil respond differently when seismic waves move through them. Ice makes the surrounding material stiffer, allowing vibrations to travel two to three times faster than they do through dry soil.
Ice-rich areas can also reflect seismic energy instead of allowing it to continue through the ground. The effect is similar to sound bouncing off a wall and producing an echo. According to Schmerr, a seismometer placed in the right location on the moon could detect both of these changes.
"We can use seismic waves to not just see whether ice is present but also roughly how much of it there is," he explained.
Testing the Seismic Signature of Moon Ice
The research team examined the idea in three different ways.
Lead author Harrison Lisabeth (Ph.D. '16, geology), a rock physicist at Lawrence Berkeley National Laboratory and UMD alum, worked with volcanic rock from Arizona. When crushed, the material closely resembles lunar dust. Lisabeth froze the rock and used X-rays to observe how ice formed inside the tiny spaces between individual grains.
Co-author Matthew Siegler of the University of Hawaii created detailed temperature models for the moon's south polar region. These maps helped identify craters that have remained cold enough to preserve ice for billions of years.
At UMD, Schmerr used computer simulations to model small moonquakes traveling through underground deposits of lunar ice. Across all three approaches, the presence of ice produced distinct and measurable changes in the seismic results.
Lunar Ice May Preserve Ancient Solar System History
Moon ice could be useful for astronauts, but it may also contain important evidence about the early solar system.
Deeply shadowed lunar craters can trap water and other volatile materials for extremely long periods. Because the surrounding rocks are about four billion years old, the ice preserved there may offer clues about how water moved through the young solar system.
"The moon witnessed some of the most critical parts of the early solar system, including how water was delivered," Schmerr said. "Studying the ice deposited there could reveal how water spread and ultimately how Earth's oceans formed."
Upcoming Missions Could Test the Method
The researchers may soon have an opportunity to compare their predictions with real measurements from the moon.
China's Chang'e-7 mission is expected to land near Shackleton Crater in late 2026. The mission will carry a seismometer, and several suspected ice deposits are located nearby.
NASA's Artemis astronauts could also deploy the Lunar Environmental Monitoring Station in 2028. Schmerr helped develop the instrument for seismic exploration.
"Our findings are laying the groundwork for an observation we'll get in the next couple of years," Schmerr said. "No one has physically measured the ice on the moon yet, but we now have a prediction for what to look out for. That's an important first step."
This research was funded by the U.S. Department of Energy Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division (Contract No. DEAC02-05CH11231), and the NASA Solar System Exploration Research Virtual Institute CLEVER project (Grant No. GR00024738) and GEODES project (Grant No. 80NSSC19M0216). This article does not necessarily reflect the views of these organizations.
