Seismic Waves Could Reveal Ice Hidden on the Moon
A study published July 31 shows that ice on the Moon could be detected and measured through seismic waves. The first real test comes from a Chinese probe landing near Shackleton crater late this year.
Ice on the Moon could be found and measured using seismic waves, according to a study that geologists from the University of Maryland, Lawrence Berkeley National Laboratory and the University of Hawaii published on July 31, 2026, in the journal Science Advances. Through calculations and laboratory experiments, the authors argue that frozen ground leaves a distinct signature in vibrations, one that can reveal not just whether ice is present but roughly how much. The first chance to put the idea to the test comes within a few months, at the Shackleton crater near the lunar south pole.
Why look for it at all. Water is the most expensive thing a crew can bring from Earth. Melted and purified, an ice deposit becomes drinking water, and split by electricity it becomes oxygen to breathe and hydrogen for fuel. That is why the south pole region was chosen for crewed landings under the Artemis program in 2028, even though how much ice actually sits there remains unknown. Satellites can scan the surface from orbit, but they only see the top layer of soil, while deposits may lie far deeper.
“It’s critical to identify all the materials on the Moon that an astronaut could use while they’re up there,” said Nicholas Schmerr, associate professor of geology at the University of Maryland and a coauthor of the study.
Why ice shows up in vibrations
The basic idea is simple. Dry ground and frozen ground do not behave the same way when a seismic wave passes through them. Ice stiffens the material it is mixed into, so vibrations travel through it two to three times faster than through dry dust. Ice-rich zones bounce part of that energy back instead of letting it pass, much like an echo off a wall. A well-placed seismometer would pick up those differences.
“We can use seismic waves not just to see whether there’s ice, but roughly how much there is,” Schmerr said in a university statement.
How the study was done
The team approached the problem from three directions:
- lead author Harrison Lisabeth, a rock physicist at Lawrence Berkeley National Laboratory, froze volcanic rock from Arizona that, once ground down, closely mimics lunar dust, then used X-rays to track how the ice settled into the tiny cracks between grains
- Matthew Siegler of the University of Hawaii built detailed temperature maps of the south pole and singled out craters that have stayed cold enough for ice to survive inside them for billions of years
- Schmerr ran computer simulations at Maryland of weak moonquakes passing through ice-bearing ground
In every simulation, the ice left a clear, measurable signature in the seismic data. That is a prediction, not a measurement: no one has yet physically measured ice on the Moon.
The first test comes with Chang’e-7
China’s Chang’e-7 mission, which carries a seismometer, is set to land near Shackleton crater in late 2026, in an area that holds several suspected ice deposits. The next step is Artemis, whose astronauts would set up, in 2028, a monitoring outpost on the lunar surface, the Lunar Environment Monitoring Station (LEMS), an instrument Schmerr helped develop.
“Our findings lay the groundwork for the observations we’ll get over the next two years,” Schmerr said.
The same instrument also measures the danger
A seismometer at the south pole would not just do a geologist’s job of hunting for water. Schmerr, together with Thomas Watters of the Smithsonian, published a study in the same journal a year earlier on how dangerous moonquakes could be for future bases. By analyzing landslides and rockfalls at the Apollo 17 landing site, they estimated that over the past 90 million years the Lee-Lincoln fault has repeatedly produced quakes of roughly magnitude 3.0 in the Taurus-Littrow valley, and that the fault may not yet be fully settled. Their math puts the odds of a damaging quake striking near an active fault on any given day at one in 20 million, which over a decade of a permanent crew works out to roughly one in 5,500.
Prospecting and risk assessment, in other words, rely on the same data. Every vibration recorded in the polar ground says something both about where the ice is and about how much the ground is shifting.
The ice carries value beyond its use as a resource, too. Lunar rocks are about four billion years old, and shadowed craters freeze and preserve volatile materials with little change over vast stretches of time.
“The Moon witnessed some of the most important parts of the early solar system, including how water got delivered,” Schmerr said.
What the study does not show
The study does not show that ice exists near Shackleton, or how much. It shows what a seismic record would look like if ice is there. The lab work used volcanic rock from Earth that mimics lunar dust, not an actual Moon sample, so the figures drawn from the experiment carry over to the Moon only under assumptions about how densely packed and how cold the ground is. The temperature maps show which craters could preserve ice, not which ones actually hold it. And how much ice can be estimated also depends on how many quakes a seismometer picks up and how close to a deposit it happens to be placed, neither of which is known in advance. Whether ice is really there, and how much, is a question only an instrument on the ground can answer.
