The Moon Is Shrinking and It's Threatening NASA's Artemis Lunar Mission

The moon, long perceived as a static celestial body, is revealing signs of change, and it could pose challenges for NASA's Artemis lunar mission.

The revelation comes from a recent study published in the Planetary Science Journal, shedding light on the lunar surface's evolving nature and its potential impact on future missions and lunar settlements.

For years, NASA has been aware of the moon's contraction, attributed to the cooling of its interior and the resulting brittle crust fractures, forming what scientists term "thrust faults."

These geological shifts can trigger moonquakes, a phenomenon observed through the Apollo Passive Seismic Network during the Apollo missions.

Moonquakes

In 2019, scientists estimated a contraction of approximately 150 feet in the moon's diameter over the last few hundred million years.

However, the study points out that some of these thrust faults are alarmingly close to identified landing sites for NASA's Artemis III mission, raising concerns about the mission's feasibility and the long-term sustainability of lunar settlements.

The Artemis program, designed to return humans to the lunar surface, has identified the lunar South Pole as a strategic area for exploration.

The study, funded by NASA's Lunar Reconnaissance Orbiter (LRO) mission, suggests that the cooling and shrinking moon's interior may induce shallow moonquakes, particularly in the south polar region, impacting stability in potential landing zones.

"Our modeling suggests that shallow moonquakes capable of producing strong ground shaking in the south polar region are possible from slip events on existing faults or the formation of new thrust faults," said Tom Watters of the Smithsonian Institution, Washington, lead author of the study.

Young Thrust Faults

The LRO Camera aboard NASA's Lunar Reconnaissance Orbiter has identified numerous young thrust faults on the lunar crust, presenting as cliff-like landforms.

These formations result from contractional forces breaking and pushing the crust, a consequence of the moon's interior cooling and tidal forces exerted by Earth, causing a global shrinking effect.

The study also models the stability of surface slopes in the lunar south polar region, identifying areas susceptible to regolith landslides even from light seismic shaking. Notably, some of these vulnerable regions are situated in permanently shadowed areas.

NASA highlights the need for new seismic data, not just at the lunar South Pole but globally, to better understand the seismic hazards that future lunar activities may face.

Upcoming missions, like the Farside Seismic Suite, aim to enhance seismic measurements and expand our knowledge of lunar seismicity beyond what was captured during the Apollo missions.

This research underscores the evolving nature of the moon and the imperative for comprehensive data collection to ensure the success and safety of future lunar exploration endeavors.

As NASA embarks on the Artemis program, the challenges posed by the moon's changing landscape necessitate a nuanced approach to mission planning and settlement development.