This structure presumably was formed 3.8 billion years ago.
Scientists announced that the unusual layered structure on the moon that resemble ancient amphitheatres, appeared on Earth in the distant past because of outpourings of magma, caused by falling asteroids and the destruction of craters.
The findings of scientists was published in the journal Science.
The researchers analyzed images that were made by the GRAIL probes in the last days of their work during flights over the Eastern sea of the moon. It turned out that it is a giant multi-stage crater in the Western part of the visible hemisphere of the moon, whose diameter, according to the latest estimates by NASA, is about 930 kilometers. This structure presumably was formed 3.8 billion years ago, at the end of the era of “late heavy bombardment”, when the Earth and her companion are constantly “bombarding” large asteroids.
The researchers found that the asteroid has created the crater, whose dimensions were two times less than the current size of the Eastern sea – 320-460 kilometers. This decline was so strong that it completely “ripped off” the entire crust from the moon’s surface at a given point of its surface, throwing about three million cubic kilometres of matter into the surrounding space, part of which then settled on the surface of the companion of the Earth. The crater was so deep that he was unstable from the gravitational point of view, and its walls almost immediately collapsed.
As a result of the collapse of the hot matter of the mantle of the moon rushed to the bottom of the crater, quickly filling it and raising it to a height of about a kilometer. As a result of the movement of the crust in the vicinity of the crater, which was this lava moments before the fall, just cracked, with the result that had two outer rings of the moon “amphitheatre”.
Then the remaining “bubble” of lava began to spread on the inner part of the crater, forming the lower steps of the amphitheatre. According to researchers, similar processes once occurred on Mars and other planets of the Solar system.
