During the study of the consequences of the collision of the Dart mission with the asteroid Dimorph, scientists discovered that this celestial body was formed no later than 300 thousand years ago, approximately at the same time when on the territory of Africa the first Cro-Magnons appeared. This is stated in a series of scientific papers published in the journal Nature Communications.
"Our analysis of images of the craters on the surface of Didymus and Dimorphus shows that the first celestial body is about 40-130 times older than its companion, and yet it turns out to be significantly younger than other asteroids of the Baptistina family. In turn, Dimorph was formed no later than 300,000 years ago, which is quite recent by the standards of astronomy, and at the same time its surface may have been updated several times subsequently," the researchers wrote.
This conclusion was reached by the Dart science team, led by Johns Hopkins University Applied Physics Laboratory researcher Andrew Rivkin, in a comprehensive study of images and science data that were obtained by the Dart probe's camera before the collision with Dimorph, as well as with the LICIACube microsatellite immediately after the event.
Using these photos and information, scientists produced accurate 3D maps of the surface of the two asteroids, allowing them to estimate how many large and small craters there are on Didymus and Dimorph. Their number, as noted by the researchers, allows us to calculate the age of the celestial body, or at least to determine the time when its entire surface was renewed as a result of some superpowerful cataclysm.
The maps analyzed by the scientists of the surface of Didymus and Dimorph show that both asteroids are very young by cosmic standards. The first appeared at least 12.5 million years ago and subsequently underwent several structural rearrangements, including those associated with the formation of Dimorph, and the second appeared no later than 300 thousand years ago, approximately in the same era, when the first Homo sapiens appeared in Africa.
In addition, the scientists found that both asteroids are composed of extremely friable and fragile matter, which withstands loads about three orders of magnitude worse than the Earth's sand or the lunar soil regolith.
This explains why the collision of Dimorph with the Dart probe led to a global deformation of the surface of this celestial body, as well as evidence in favour of the fact that it was formed from debris ejected from the surface of Didymus, the researchers conclude. | BGNES
