The moon appears to have changed shape significantly over the past few hundred million years and the contractions have raised doubt about the feasibility of establishing colonies on the moon because of the likelihood of moonquakes.
The discovery comes after the unsuccessful Peregrine 1 project, which was intended to be the first US soft landing on the moon since the early 1970s. The Nasa commercial mission was aborted after the spacecraft lost propellant and it burnt up as it re-entered the Earth's atmosphere on January 18.
So what is happening to the moon and why does it matter?
Here's what we know.
Is the moon actually shrinking?
The study, which was published in the Planetary Science, claimed that during the previous few hundred million years, the moon's core has got steadily colder, causing the moon's circumference to shrink by more than 150 feet.
Moonquakes arise from the creation of faults caused by the satellite becoming smaller. Scientists from Nasa, the Smithsonian, Arizona State University and the University of Maryland discovered that the shrinking caused surface changes near the lunar south pole.
Thousands of very small, immature thrust faults are extensively dispersed throughout the lunar crust, and the researchers were able to identify them thanks to the Lunar Reconnaissance Orbiter Camera on Nasa's Lunar Reconnaissance Orbiter.
Why is the moon shrinking?
According to the study, the contraction is brought on by Earth's tidal forces and the cooling of the moon's still heated interior.
Moonquakes, which are similar to earthquakes in that they are triggered by internal faults in the moon, have the potential to do harm to technology and structures built by humans on the moon, according to scientists.
However, moonquakes can continue for hours or even an entire afternoon, in contrast to earthquakes, which only last a few seconds. As a result, these shallow quakes have the potential to completely destroy future human settlements.
Why does it matter?
Scientists caution that future human explorers may find themselves in peril in areas close to fault zones. But there isn't much cause for concern among Earthlings. Since the shrinkages are small, they won't affect tidal cycles, eclipses or full moons.
Co-author Thomas Watters from the National Air and Space Museum said: “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.”
The next moon watching date for your calendar
The next moon watching date is on Friday February 9 at 22:59. On this date a new moon will occur, which takes place once every month.
When the moon is exactly between Earth and the Sun, with its darkened side facing our direction, it is said to be new. When a solar eclipse occurs, a new moon can be seen when it passes across the face of the Sun.
