A new study indicates that the moon's shrinking, accompanied by seismic activity like moonquakes, could lead to an increase in landslides, potentially posing dangers to future astronauts in areas near fault zones.
Researchers from the University of Maryland report that the Earth's natural satellite, the moon, has lost up to 100m in circumference over the past few hundred million years due to its core cooling, causing significant surface warping in parts of the lunar south pole.
"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 study co-author Thomas Watters from the National Air and Space Museum.
Researchers have linked faults in the moon's southern polar region to a powerful moonquake recorded by Apollo seismometers over 50 years ago, revealing that certain areas of the Moon's south pole are particularly susceptible to landslides from seismic shaking.
Moonquakes, caused by faults in the moon's interior, can damage human-made structures and equipment on the lunar surface. They can last for hours or even an entire afternoon, potentially devastating for future human settlements.
This is due to loose sediment on the Moon's surface, formed from billions of years of asteroid and comet collisions.
The moon's surface is composed of "dry, grounded gravel and dust," which has been impacted by asteroids and comets over billions of years, according to Dr Nicholas Schmerr, another author of the study.
The resulting fragments, ranging from micron-sized to boulder-sized, are loosely consolidated, making them susceptible to shaking and landslides.
Nasa plans to launch its first crewed flight to the moon in over five decades as part of the Artemis mission in late 2024. Researchers aim to identify more dangerous locations on the moon for future human exploration.
"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," Dr Schmerr said.