New Research Reveals the Moon Is Shrinking Like a Raisin—Here's What That Means for Us

The moon is shrinking, much like the way a grape wrinkles when it turns into a raisin, according to new research published in The Planetary Science Journal.

While this may sound alarming, the shrinkage is too small to affect people living on Earth. Over the past couple hundred million years, the moon shrank only about 150 feet in circumference, University of Maryland news release about the findings states.

However, the shrinkage could disrupt NASA's Artemis III missions—the first Artemis mission planned to have a crewed lunar landing. The scientists found that this continuing shrinkage of the moon led to notable surface warping in its south polar region, including areas NASA identified as candidate landing regions for Artemis III.

Fault formation caused by the shrinkage is often accompanied by seismic activity like moonquakes, meaning locations near or within the fault zones could be too dangerous for human exploration. In fact, the team behind the research linked a group of faults in the south polar region to one of the most powerful moonquakes recorded by Apollo seismometers.

"The global distribution of young thrust faults, their potential to be active, and the potential to form new thrust faults from ongoing global contraction should be considered when planning the location and stability of permanent outposts on the Moon," said the study’s lead author Thomas R. Watters.

Shallow moonquakes occur near the surface of the moon (about a hundred miles deep into the crust) and are caused by faults in the moon’s interior. According to the press release, moonquakes can last for hours and can be strong enough to damage buildings, equipment, and other human-made structures.

The researchers will continue to map out the moon to hopefully identify more locations that may be dangerous for human exploration. "As we get closer to the crewed Artemis mission’s launch date, it’s important to keep our astronauts, our equipment and infrastructure as safe as possible," said Nicholas Schmerr, a co-author of the paper. "This work is helping us prepare for what awaits us on the moon—whether that’s engineering structures that can better withstand lunar seismic activity or protecting people from really dangerous zones."