- The Moon is shrinking due to cooling and contraction of its interior over time
- Surface crust wrinkles and compresses, forming lobate scarps and small mare ridges
- These tectonic features indicate the Moon remains geologically active without plate tectonics
The Moon - Earth's closest celestial neighbour - is slowly shrinking as its interior cools, according to research by scientists studying lunar geology. While the process has been unfolding for billions of years, new analysis suggests the contraction may be happening faster than previously estimated. Researchers at the National Air and Space Museum's Centre for Earth and Planetary Studies say the phenomenon is linked to the gradual cooling of the Moon's interior. As the Moon loses heat over time, its interior contracts, causing the surface crust to wrinkle and compress.
The discovery builds on work by Thomas R Watters, a senior scientist emeritus at the centre, who first presented evidence in 2010 that the Moon has been shrinking over geological time.
What If the Moon Disappeared?
Scientists stress that the Moon is not vanishing anytime soon. But if it did disappear, the consequences for Earth would be profound. The Moon stabilises Earth's axial tilt, moderates ocean tides and influences long-term climate patterns.
Without it, researchers say Earth could experience far more extreme climate shifts, unstable seasons and dramatically weaker tides - fundamentally altering life on the planet.
A phenomenon like this occurred more than 900 years ago that saw torrential rainfall damaging crops and famine stalking the land and the Moon 'disappearing'. "On the fifth night in the month of May appeared the moon shining bright in the evening, and afterwards by little and little its light diminished," one scribe wrote in the Anglo-Saxon manuscript known as the Peterborough Chronicle in the year 1110, as per Live Science.
"As soon as night came, it was so completely extinguished withal, that neither light, nor orb, nor anything at all of it was seen. And so it continued nearly until day, and then appeared shining full and bright," the article further said.
Researchers later attributed this disappearance to a "veil" of sulfur-rich particles in the stratosphere from a volcanic eruption.
How The Moon Is Shrinking
As the Moon cools, its surface develops tectonic features known as lobate scarps - small cliff-like ridges formed when the crust compresses and thrusts upward. Scientists have also identified small mare ridges (SMRs) across the lunar surface, suggesting that the Moon is still undergoing subtle geological changes.
According to research published in scientific journals and cited by NASA and other space agencies, these features are relatively young in geological terms. Their presence indicates that the Moon remains tectonically active, even though it lacks plate tectonics like Earth.
Researchers say understanding these structures is crucial because they may reveal new sources of moonquakes, which could influence where future lunar missions land.
"Since the Apollo era, we've known about lobate scarps throughout the lunar highlands," said Cole Nypaver, lead author of the study, quoted by Science Daily. The latest findings show similar structures are widespread across lunar plains, offering new insights into the Moon's internal history.
