Mysterious moonquakes that occur every day are actually linked to the abandoned Apollo 17 moon base, according to a recent study.
• Read also: Two Russians and an American arrive on the ISS
• Read also: NASA manages to produce 122 grams of oxygen on Mars
• Read also: From the Moon to the Sun: India launches its next space mission
Researchers from California Institute of Technology analyzed data collected over an 8-month period between 1976 and 1977 by seismic sensors installed by the Apollo 17 astronauts.
The graphs created from these show thermal Moonquakes which occur with regularity every day at the same time, in the afternoon, when the sun begins to descend and the temperature begins to drop on the star.
Another seismic activity was, however, captured by the devices affixed by the astronauts, and would be very different from the first.
It would occur every lunar morning and would be characterized by several small, regular seismic signals, which prompted scientists to study it in depth.
They determined that it would ultimately not be a question of lunar tremors, but of the expansion of the Apollo 17 lunar base, located a few hundred meters from the sensors, due to the radical increase in temperature when hit by the sun’s rays.
The temperature on the Moon goes from 121 degrees Celsius during the day to -133 at night, which would have caused this expansion of the materials that make up the lunar base and whose friction with the ground was captured by seismic devices.
“Every lunar morning when the sun hits the lunar base, it starts to move,” says geophysics professor and co-author of the study, Allen Husker, in a press release.
Although it is well documented that the Moon does not have tectonic plates, researchers still wonder about its internal structure.
“It is important to analyze the data we already have to be able to better guide future experiments and missions in order to answer the right questions,” continues Mr. Husker.
The Moonquakes captured are too weak to be felt on the surface, but they give scientists important information about the expansion that future moonlanders will need to be able to absorb in order to complete their missions.