By Dean Murray
New research confirms the moon is shrinking.
Studies have uncovered over a thousand previously unknown tectonic ridges across our celestial neighbor’s surface that show it is contracting.
The find could help keep upcoming lunar exploration missions safe by assessing potential for future moonquakes.
Smithsonian planetary scientists identified the Moon’s ongoing geological activity by examining small mare ridges (SMRs), which are among the youngest features on the lunar surface, and formed by the same compressional forces driving the Moon’s global shrinkage.
The findings build on evidence that the Moon has shrunk by roughly 50 meters in diameter over hundreds of millions of years as its interior cools, creating thrust faults and potential moonquake hotspots.
These recent structures in the lunar maria could trigger seismic events, posing challenges for future missions like NASA’s Artemis programme targeting the lunar south pole.
Tom Watters, a senior scientist emeritus at the Center for Earth and Planetary Studies, said: “Our detection of young, small ridges in the maria, and our discovery of their cause, completes a global picture of a dynamic, contracting moon.”
Cole Nypaver, a post-doctoral research geologist at the Center for Earth and Planetary Studies and the first author on the paper, said: “Since the Apollo era, we’ve known about the prevalence of lobate scarps throughout the lunar highlands, but this is the first time scientists have documented the widespread prevalence of similar features throughout the lunar mare.
“This work helps us gain a globally complete perspective on recent lunar tectonism on the moon, which will lead to a greater understanding of its interior and its thermal and seismic history, and the potential for future moonquakes.
“We are in a very exciting time for lunar science and exploration. Upcoming lunar exploration programs, such as Artemis, will provide a wealth of new information about our moon.
“A better understanding of lunar tectonics and seismic activity will directly benefit the safety and scientific success of those and future missions.”
