The Moon, long treated as a geologically inert relic, is still contracting and cracking. A growing body of peer-reviewed research now confirms that tectonic faulting on the lunar surface has occurred within the last few million years, and some of it may be ongoing. That finding carries real consequences for future crewed missions, because faults that slip can trigger moonquakes strong enough to shake loose boulders and destabilize slopes near planned landing zones.
A Shrinking World Still Breaking Apart
As the Moon’s interior slowly cools, the entire body contracts, much like a grape drying into a raisin. That contraction pushes crustal blocks together and creates thrust faults that show up on the surface as low ridges called lobate scarps. Thousands of these scarps have been mapped in high-resolution imagery, and individual examples appear as sharply defined, curving ridges that cut across craters and smooth plains. What makes the scarps remarkable is how fresh they look. Images from the Lunar Reconnaissance Orbiter Camera reveal bright, minimally weathered material, fresh landslides, and boulder tracks along fault faces, all signs that the faulting is geologically recent rather than billions of years old.
A peer-reviewed study in Nature Geoscience examined hundreds of small-scale tectonic landforms and identified crisp, minimally degraded graben (shallow troughs that open when the surface stretches) adjacent to compressional scarps. By modeling how quickly such features should soften and erode under micrometeorite bombardment and thermal cycling, the authors concluded that many formed within the last 50 million years, with some much younger. Follow-up work published in Icarus pushed the timeline closer to the present, documenting sub-meter-deep extensional fractures in the hanging walls of lobate scarps whose sharp morphology implies activity within just the last few million years. Together, these studies challenge the older assumption that the Moon finished reshaping itself long ago and instead present a world that is still adjusting to its gradual loss of internal heat.
Moonquakes Traced to Fault Scarps, Not Meteoroids
Seismic evidence increasingly ties specific faults to specific moonquakes. A study by Watters and Schmerr in Science Advances analyzed boulder falls and landslides in the Taurus-Littrow valley, the site explored by Apollo 17 astronauts, and concluded that they were triggered by tectonic shaking rather than meteoroid impacts. By using exposure ages of displaced boulders and modeling the forces required to move them, the team inferred body-wave magnitudes of roughly 2.9 to 3.3 for the causative quakes. Those magnitudes are modest on Earth but significant on an airless body where loose regolith, steep crater walls, and tall boulder piles are common near potential landing and habitat sites.
NASA’s broader analysis supports this link between contractional faulting and seismicity. The agency reports that the ongoing shrinkage of the lunar interior, combined with tidal stresses from Earth, can generate shallow moonquakes along young thrust faults. According to this work, Earth’s gravity not only flexes the Moon but also influences the preferred orientations of active scarps, effectively “massaging” the crust so that faults align with the strongest tidal stress directions. One line of interpretation describes the Apollo-era evidence as revealing “ancient” activity, while the Watters and Schmerr results emphasize recent reactivation, but both can be true: faults that initiated hundreds of millions of years ago can continue to slip in smaller, episodic events. For mission planners, the key point is that some of these structures are still capable of producing shaking strong enough to dislodge rocks and destabilize slopes today.
Mapping the Full Scale of Recent Tectonics
Individual fault studies are compelling, but understanding risk for future missions requires a global view of where the crust is still deforming. Smithsonian planetary scientists recently produced a comprehensive catalog of small compressional ridges across the dark volcanic plains, identifying 1,114 previously unmapped segments and bringing the total to 2,634. The team estimated an average age of about 124 million years for these features, which is extremely young on a 4.5‑billion‑year‑old world. Their distribution shows that contractional tectonics is not confined to a few isolated basins but affects mare regions across much of the lunar near side and far side, suggesting a global stress field that remains active on geologic timescales.
Targeted case studies add depth to this emerging picture. Work on a prominent fault in Jules Verne Crater used orbital data to reconstruct the evolution of a large scarp, tying surface offsets to layered deposits and impact structures to constrain the sequence of deformation. Other research from Brown University has argued that some ridges overlying buried magmatic intrusions are still being pushed upward, implying that residual magmatic or thermal processes may supplement simple cooling and contraction in driving present-day tectonism. Taken together, the global mapping and local reconstructions point to a Moon where multiple mechanisms (cooling, tidal flexing, and subsurface intrusions) combine to keep the crust in slow but measurable motion.
Implications for Artemis Landing Sites and Habitats
For NASA’s Artemis program and other planned crewed missions, the existence of active faults is not just a scientific curiosity; it is a design constraint. Analyses of historical seismic data and modern imagery have begun to quantify how often tectonic events might threaten infrastructure. One recent modeling effort, available through an open-access lunar hazard assessment, illustrates how shallow moonquakes could interact with local topography to amplify ground motion, particularly along crater rims and steep scarps. The combination of loose regolith, low gravity, and abrupt slopes means that even moderate shaking may be sufficient to topple boulders or trigger dry granular flows, especially in regions already marked by fresh landslides and boulder tracks.
That risk is especially relevant near the lunar south pole, where many Artemis landing zones have been proposed. A recent study in The Planetary Science Journal modeled how active scarps near the poles might respond to ongoing contraction and tidal stresses, finding that some polar regions could experience repeated small quakes over million‑year timescales. While the probability of a mission‑ending event during any single expedition is low, the cumulative risk rises for permanent bases, fuel depots, and long‑lived surface power systems. Engineers therefore need to factor tectonic hazards into site selection, favoring locations away from the steepest scarp faces and known boulder-fall zones, and to design structures that can tolerate intermittent shaking without catastrophic failure.
Designing for a Slowly Moving Moon
Mitigating lunar tectonic hazards will likely involve a mix of smart siting, robust structural design, and continuous monitoring. Landing and habitat sites can be placed on relatively flat, low-slope terrain set back from obvious fault scarps and crater walls, reducing exposure to rockfalls and slides. Foundations may need to be anchored more deeply into competent bedrock or engineered regolith pads to limit differential settlement during shaking. Critical systems such as habitats, power units, and propellant tanks could be clustered to simplify protective berms or shielding, while nonessential equipment is sited farther downslope where potential debris paths are less threatening.
At the same time, future crews and robotic precursors can deploy seismometers, ground-penetrating radar, and repeat-imaging campaigns to refine local hazard models in near real time. Networks of small, distributed instruments would help pinpoint active faults, track the frequency and magnitude of moonquakes, and test whether particular scarps are still slipping. Over the coming decades, this feedback loop, combining global mapping, detailed fault studies, and on-the-ground monitoring, will turn the Moon’s subtle tectonic rumblings from a poorly constrained risk into a manageable engineering factor. Rather than a dead, unchanging landscape, the Moon is emerging as a slowly evolving world, and successful long-term exploration will depend on learning to live with its ongoing, if gentle, geological restlessness.
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*This article was researched with the help of AI, with human editors creating the final content.
