On Mars, there were scars from 5 giant blows, including the ancient Great Northern Plain (above), Hellas (bottom right) and Argyer (bottom left).
The collisions occurred from the very beginning of the formation of the solar system and played a decisive role in the creation and evolution of planets and other celestial bodies. Studying the history of the early bombardment of Mars, scientists from the Southwestern Research Institute and the University of Arizona discovered a 400-million respite between major clashes at the beginning of the history of the Red Planet. The lead author of the study is Bill Botke.
“According to the new results, the shock Martian history is closely connected with the bombings assumed for the Moon, the asteroid belt and Mercury,” said Bottke. “We refer to the period of earlier attacks, such as the Late heavy bombardment. The data throw new information into the controversial theory. It seems that calm is the most important period in the evolution of Mars and other planets. We call it the “depressive state.”
The early shock attack of Mars is directly related to the history of the entire inner solar system as a whole. The Great Northern Plain is the largest and oldest Martian basin. The width extends over 6000 miles and covers most of the northern hemisphere. New evidence shows that its edge was excavated by one much later crater, known as the Isis plain. This puts statistical restrictions on the number of basins that could have formed on Mars after the northern plain. Moreover, the state of preservation of the foursomes of the youngest large basins (Hellas, Isis, Argir and Utopia) is incredibly similar to the states of the much larger and older Great Northern Plain. Then, relying on this, it must be the case that all the pools between them must remain the same. But none passed the test.
“Previous studies have shown that the age of Hellas, Isis and Argyrs is 3.8–4.1 billion years old,” says Bottke.
Scientists believe that the plain was created from shock fragments, which after reached the Earth. And this means that the Great Northern Plain is 4.5 billion years old. That is, as old as the planet.
The study takes a new look at the history of the bombing. A giant blow carved the northern depressions 4.5 billion years ago. After that, Mars remained calm for 400 million years. Then came the second period of attacks, creating basins 4.1-3.8 billion years ago. Their age is different and requires other foreign shock objects. It turns out that the first shock wave touched the moment of the formation of the inner planets, and the second one has already damaged the Martian surface fairly.