The Moon Is Getting Smaller and Wrinklier — Here's Why
The physical effects of aging on a human body are universal: our skin gets wrinklier, we get smaller. Apparently, the moon is aging the same way.
According to images from NASA's Lunar Reconnaissance Orbiter, the moon is shrinking, which is causing its crust to wrinkle up. The shrinking is also causing moonquakes, which are similar to their earthly equivalents — earthquakes.
Whereas the Earth’s quakes are caused by the shifting of tectonic plates, the moon’s quakes are caused by the body’s cooling. As the inside of the moon cools down, its surface shrivels up. Think of a grape shriveling into a raisin. However, unlike a grape, the moon’s surface is brittle and when these wrinkles form, the surface can break, “resulting in so-called thrust faults, where one section of crust is pushed up over an adjacent section,” according to AFP.
According to NASA’s images, this process has caused the moon to shrink about 50 meters, or about 164 feet, in diameter from what it was back in 1972.
Researchers believe this process is still active on the moon, meaning it is still changing and still experiencing quakes.
“For me, these findings emphasize that we need to go back to the moon,” Nicholas Schmerr, assistant professor of geology at the University of Maryland an an author of the study, said in a statement. “We learned a lot from the Apollo missions, but they really only scratched the surface. With a larger network of modern seismometers, we could make huge strides in our understanding of the moon's geology. This provides some very promising low-hanging fruit for science on a future mission to the moon.”
We may not have to wait long. NASA announced earlier this year that it hopes to send astronauts back to the moon in 2024.