Scientists at the California University of Technology have found that the Apollo 17’s left-over lunar module is causing ‘moonquakes’ on the lunar surface.
A new study by researchers from the California University of Technology has revealed that the Apollo’s left-over lunar module is causing tiny “moonquakes” on the lunar surface.
Apollo 17 was launched in December 1972, when NASA astronauts Gene Cernan and Harrison Schmitt landed on the moon and left few things behind- a US flag, a Moon buggy and lunar module’s descent stage. It is this module that is now shaking the lunar surface.
The left-over lunar module contained an array of four geophones that are used to conduct seismic activity. They were reactivated between October 1976 and May 1977 for passive listening. These seismometers recorded thousands of subtle tremors on the moon.
Moonquakes on lunar surface
The tremors on the lunar surface are caused by the result of daily temperature variations. Unlike Earth, the surface of the Moon does not have atmosphere to insulate itself. Therefore, it experiences temperature variations between day and night.
When the lunar surface heats up, it expands, and when it cools down again, it contracts. These movements result in cracking near the surface and tremors known as “thermal moonquakes”.
How is Apollo 17’s left-over tech causing moonquakes?
The team of geophysicist Allen Husker of the California University of Technology found that thermal moonquakes occur with the regularity of clockwork, every morning and afternoon. The latter are the result of the Sun leaving its peak position in the sky, allowing the lunar surface to begin to cool off.
However, the team’s artificial intelligence model revealed that the seismic activity detected in the morning has a different profile and are not regular thermal moonquakes at all.
Using the data from the seismometer array to triangulate the source of the morning quakes, Husker and his team found that they were coming from the left-behind descent stage of the Apollo 17 lunar module.
Lying mere hundreds of feet from the geophones, this lander base comprises an octagonal prism some 14 feet across, mounted on four legs and with an attached ladder for astronauts to climb in and out of the module that sat atop it.
The researchers believe that it is causing the extra moonquakes when it warms up and expands in the morning sunlight.
These findings from Apollo 17’s lunar module can help NASA as they plan to return humans to the Moon in the coming years as part of the Artemis mission.
(Wion, With inputs from agencies)