The Moon Never Stopped Moving
For decades, planetary scientists treated the Moon as a dead world—geologically frozen in time since the end of heavy bombardment billions of years ago. New research from the National Air and Space Museum's Center for Earth and Planetary Studies has shattered that assumption. A comprehensive global map of small mare ridges (SMRs) reveals that the Moon is actively reshaping itself, with tectonic activity far more recent and widespread than previously understood.
The findings, published in The Planetary Science Journal in December 2025, matter immediately: they fundamentally alter how space agencies should approach site selection for permanent lunar bases and long-duration missions. If the Moon can still generate moonquakes—and the evidence suggests it can—those tremors pose real risks to infrastructure, equipment, and human operations.
Why SMRs Matter More Than They Sound
Small mare ridges are subtle geological features—essentially wrinkles in the Moon's dark lava plains (the "maria"). But their presence tells a critical story: the Moon is still contracting. Unlike Earth, which maintains internal heat through radioactive decay and generates tectonics through plate interactions, the Moon cools slowly from its molten core outward. As it cools, it shrinks. That shrinkage creates stress in the lunar crust, which relieves itself through faulting and ridge formation.
What makes this discovery pivotal is the age of these features. The research team determined that SMRs are geologically young—meaning they formed within the last billion years, and possibly much more recently. For context, that's roughly equivalent to finding evidence of earthquakes happening during the age of dinosaurs and beyond—recent on a geological timescale. Some ridges may have formed within the past 100 million years, making them practically newborns in planetary terms.
The distribution is equally significant: SMRs are scattered across the lunar maria, not isolated to a single region. This widespread pattern suggests the Moon's contraction is a global phenomenon, not a localized quirk. Previous models underestimated both the extent and the active nature of this process.
The Industry Implications
For NASA, China's space program, and private lunar ventures like Axiom Space and Intuitive Machines, this research shifts the calculus on mission planning. Moonquakes triggered by ridge formation could damage sensitive instruments, destabilize structures, or complicate power and communication systems. The team's identification of new potential moonquake sources directly impacts where engineers can safely position habitats, energy systems, and scientific equipment.
Historically, seismic monitoring on the Moon came from the Apollo-era seismometers (1969–1977), which recorded around 28 moonquakes per year, mostly shallow events. Modern lunar missions will carry advanced seismic networks, and these results provide crucial baseline data for interpreting new data. The implications extend to lunar tunnel systems, subsurface habitats, and any long-term infrastructure designed to withstand the environment.
What Comes Next
Upcoming missions—including NASA's Artemis III landing (expected mid-2026) and international lander programs—will test these predictions. Better seismic monitoring, ground-penetrating radar, and high-resolution imaging will help refine models of SMR formation rates and earthquake risk. For the space industry's long-term ambitions of sustained lunar presence, understanding the Moon's active geology isn't optional: it's foundational. The era of treating the Moon as a static target is officially over.
