🌕 The Moon is Shrinking, and It Shows

Recent mapping has revealed that the Moon's surface is dotted with thousands of fresh tectonic ridges, betraying a slow contraction of its internal structure.

For the first time, a scientific team has created a global map of these small wrinkles, called mare ridges. Published in The Planetary Science Journal, their research shows that these formations are young and widely distributed across the dark plains visible from Earth.


Unlike Earth where tectonic plates move, the Moon has a single crust that compresses over time. As it cools, its interior compacts, and this exerts forces that wrinkle the surface, creating these ridges. This phenomenon is comparable to that observed in the lunar highlands, but it occurs here in the maria, these vast basaltic plains.

The analysis identified over a thousand additional ridges, bringing their total number to more than 2,600. Their average age is around 124 million years, placing them among the Moon's most recent geological features. This youth indicates that our satellite is still evolving.

These ridges are not just geological curiosities; they could be associated with moonquakes. Since they form along faults similar to those in the highlands, they signal areas where tremors could occur. This discovery changes the map of seismic risks on the Moon, a factor to consider for future crewed missions.


The authors indicate that this comprehensive mapping helps anticipate where these events might occur. As programs like Artemis prepare, better knowledge of these risks will help ensure astronaut safety and organize explorations more appropriately.

What are moonquakes and how are they detected?

Moonquakes are tremors that occur on the Moon's surface. They are comparable to terrestrial earthquakes but generally less powerful.

Their origins can be multiple: meteorite impacts, tidal forces exerted by Earth, or, as this study indicates, tectonic activity related to contraction. To locate them, researchers use seismometers, instruments sensitive to vibrations. During the Apollo missions, seismometers placed on the Moon recorded many events.

Today, thanks to orbiters and upcoming missions, monitoring is gaining precision. This information helps map risk zones and examine the Moon's internal structure, which is fundamental for the safety of future human and robotic exploration.