A piece of shocking news has riveted NASA as well as the astronomical world. It’s regarding our poetic and essential Moon. As per NASA press release, the moon is currently shrinking, and it is shaking too.
It’s not completely old news but it’s shocking nonetheless. It has been a decade since scientists came to the conclusion that our beloved satellite is cooling from the inside. This is resulting in the moon shrinking, almost like a raisin. That’s the reason why it bears ‘thrust faults’ on its surface.
That was supposed to be history. New analyses is suggesting that the moon continues to shrink and now, it is going through moonquakes, accompanied by the thrust faults. The rocks are shaking near the cliffs.
According to the scientists, the process is similar to the shriveling up of grapes. Grapes generally wrinkle up and it has those lines when it shrinks. Imagine a raisin. But the surface of the moon is not flexible. It is brittle and hence, during the shrinking process, it breaks. Hence, as the crust moves or one part of the crush goes over another, the fault forms. They look unusual from the surface and can be quite long.
New research has been able to form an algorithm which could process the seismic data which had been collected back in the 1960s and 70s. Now, we can understand how the moonquakes are working. The location data generated was put on top of the thrust faults collected from a study done in 2010. These pictures were from Nasa’s Lunar Reconnaissance Orbiter.
When the images were compared, it was discovered that 8 of the quakes were actually coming from plate movements in the moon surface and not anything else, like asteroid impacts. There was confirmed tectonic activity.
Back in 1977, the astronauts had left their instruments on the surface of the moon and those instruments are doing the work. The shrinking process is still taking place as can be seen from the recent boulders that were displaced. From the Apollo Data, many quakes were discovered happening near the fault lines, as per Assistant professor of geology at the University of Maryland, Nicholas Schmerr. According to him, the faults might be active today. Such faults can’t be seen on earth, so moonquakes are something exciting.
The data was collected from instruments which had been used during the famous Apollo missions. Apollo 11 left one instrument but it was dead within a couple of weeks. The other 28 continued recording from 1969 to 1977. Since eight of the quakes were picked near the faults, a clear connection was made.
Another interesting discovery was that the quakes happen whenever the moon was furthest from Earth. It might be that the gravity of the Earth interacts and disturbs the crust of the moon.
According to the lead author of the study, Thomas Watters, tidal forces and global contractions may have resulted in stress buildup and thereafter, the slipping of the faults. It just shows that the moon is very active even now, tectonically.
For Schmerr, it is necessary for astronauts to go up there again and use modern seismometers to understand the geology of the moon properly. It would be a great leap for humankind, yet again. The Trump administration is at it too. They have ordered NASA to return to the moon and there is hope that within 5 years, they will be back there.
Let’s keep our fingers crossed.
IMAGE CREDIT: ELENA POLINA