The Moon is shrinking, wrinkling due to quakes

Shrinking Moon may be experiencing powerful quakes to this day

Shrinking Moon may be experiencing powerful quakes to this day

Published on May 13 in Nature Geoscience, the study says the moon is getting smaller as its interior cools and it has become more than about 150 feet thinner over the last hundred million years, said a NASA press release.

The moon is still tectonically active, like Earth, generating moonquakes as our planet creates earthquakes, a new study based on Apollo mission data found. The scarps form when one section of the moon's crust (left-pointing arrows) is pushed up over an adjacent section (right-pointing arrows) as the moon's interior cools and shrinks.

The moon is shrinking - much like the way a grape shrivels into a raisin - and that may be causing it to have "moonquakes", according to NASA.

The researchers in the new study wanted to see if the shallow moonquakes that the Apollo missions detected were linked with faults on the lunar surface, and thus ongoing tectonic activity on the moon.

The findings suggested that these "cliffs", or thrust faults, had formed as a result of tectonic activity related to the moon contracting in size as it cooled. Researchers suggested these faults were evidence of lunar tectonics, although it was unclear how recent this activity was.

More than 3,500 of the faults have been identified by the LRO. Seismometers are instruments that measure the shaking produced by quakes, recording the arrival time and strength of various quake waves to get a location estimate, called an epicenter. "It's quite likely that the faults are still active today". This point, which is called apogee, is also the period during which Earth's gravity inflicts the most stress, or tidal pressure, on the Moon's structure.

Those that appear brighter indicate freshly exposed rock, suggesting an event like a "moonquake". Examples of fresh boulder fields are found on the slopes of a fault scarp in the Vitello cluster and examples of possible bright features are associated with faults that occur near craters Gemma Frisius C and Mouchez L. Other LROC fault images show tracks from boulder falls, which would be expected if the fault slipped and the resulting quake sent boulders rolling down the cliff slope. With almost a decade of LRO imagery already available and more on the way in the coming years, the team would like to compare pictures of specific fault regions from different times to look for fresh evidence of recent moonquakes.

The moon is slowly shrinking over time, which is causing wrinkles in its crust and moonquakes, according to photos captured by NASA's Lunar Reconnaissance Orbiter.

Prof Schmerr said: "For me, these findings emphasise we need to go back to the Moon".

US astronauts placed seismometers on the lunar surface during the Apollo 11, 12, 14, 15 and 16 missions, recording 28 shallow quakes up to nearly 5 magnitude, which is moderate strength. Those missions even saw artificial moonquakes from the impacts of the spacecraft used to bring astronauts to the moon, Schmerr added. With a larger network of modern seismometers, we could make huge strides in our understanding of the Moon's geology.

Noticias recomendada