Moon is Shrinking Due to Frequent Earthquakes, Says Study

According to an analysis of the images captured by Lunar Reconnaissance Orbiter (LRO), Moon is steadily shrinking and is caused by the earthquakes on its surface. The study of the analysis was published in Nature Geoscience on Monday.

The study of more than 12,000 images revealed that lunar basin ‘Mare Frigoris’ near Moon’s north pole is one of many vast basins that has been cracking and shifting. Mare Frigoris is long assumed to be a dead site from a geological point of view.

Unlike Earth, the Moon doesn’t have tectonic plates, but its tectonic activity occurs when it slowly loses heat, this, in turn, causes its surface to wrinkle. The procedure is going on since it was formed 4.5 billion years ago.

The crust of the moon is fragile and the forces cause its surface to break as the interior starts to shrink, resulting in what space scientists call thrust faults, where one section of crust is pushed up over an adjacent section and as a result, the Moon has become about 150 feet thinner over the past several hundred million years.

Nicholas Schmerr, who co-authored the study is an assistant professor of geology associated with University of Maryland, says, “It’s quite likely that the faults are still active today. You don’t often get to see active tectonics anywhere but Earth, so it’s very exciting to think these faults may still be producing moonquakes”.

NASA’s Apollo astronauts first started measuring seismic activity on the surface of the Moon in 1960s and 1970s and found that the vast majority of quakes occurred deep in the interior of the Moon’s body while a smaller number have occurred on its surface.

The analysis, which was published in Nature Geoscience, also examined the shallow moonquakes recorded by the Apollo missions thus establishing links between them and the very young surface features.