Most meteorites are the result of just three asteroid collisions
Until recently, the origin of almost all meteorites was unknown. A research team could now assign more than two thirds to just three asteroid families.
More than two thirds of all known meteorites can be traced back to just three asteroid families that were formed in collisions in the main asteroid belt around six, eight and 40 million years ago. An international research team has now discovered this and added that as many as 37 percent of all known meteorites can be traced back to that collision 40 million years ago. In total, more than 90 percent of all known meteorites can now be assigned to one origin, explains France's national research center CNRS. Until recently, this was only possible for 6 percent.
No end for meteorites
The fact that collisions that occurred comparatively recently are responsible for so many meteorites is not surprising, writes the team. Young asteroid families consist of a particularly large number of small fragments, which are also fast and often leave the asteroid belt. Quite a large number then also reach Earth, where they fall down as meteorites. The asteroid families known as Karin, Koronis and Massalia, which have recently been particularly productive, would eventually make way for others if further large collisions occur between Mars and Jupiter.
This classification of the majority of all known meteorites was made possible by examining the composition of the asteroid families using telescopes and powerful simulations. This also made it possible to determine the origin of some of the largest known asteroids. Both Ryugu and Bennu come from the same asteroid family called Polana. The research team is now presenting its work in the journal Nature, among others, and intends to dedicate itself to the search for the origin of the remaining meteorites in the future.
(mho)