Recent research has established that approximately 70 percent of all known meteorite falls can be traced back to three young asteroid families: Karin, Koronis, and Massalia. This significant finding emerged from a collaborative effort involving scientists from the CNRS, the European Southern Observatory (ESO), and Charles University in the Czech Republic. These families formed through collisions in the main asteroid belt around 5.8, 7.5, and 40 million years ago, with the Massalia family being responsible for a remarkable 37 percent of all meteorite falls.
Identifying Meteorite Origins
Despite the documentation of over 70,000 meteorites, only about six percent had been definitively linked to known celestial bodies, including the Moon, Mars, or Vesta, the largest asteroid in the main belt. The origins of the remaining 94%, mainly ordinary chondrites, had remained largely unidentified until now. The abundance of small fragments from these young families increases the likelihood of collisions among them, which can result in fragments escaping the asteroid belt and potentially reaching Earth.
The Methodology Behind the Discovery
The historic discovery was made possible through a comprehensive telescopic survey of the major asteroid families, complemented by advanced computer simulations of their collisional and dynamical evolution. This innovative approach has also facilitated the identification of the origins of carbonaceous chondrites and achondrites, which expand the knowledge of meteorite sources beyond just the Moon, Mars, and Vesta.
Future Research Directions
Thanks to this research, over 90 percent of meteorite origins have now been identified. Nevertheless, the sources of the remaining 10 percent are still unknown. The research team plans to continue their investigations, focusing on characterising young asteroid families that formed less than 50 million years ago to enhance our understanding of meteorite origins and their impact on Earth.