Far out cosmology: the source of meteorites (Introduction)

by David Turell , Thursday, October 17, 2024, 20:42 (13 hours, 10 minutes ago) @ David Turell

90% identified:

https://www.sciencedaily.com/releases/2024/10/241016115629.htm

"An international team led by three researchers...has successfully demonstrated that 70% of all known meteorite falls originate from just three young asteroid families. These families were produced by three recent collisions that occurred in the main asteroid belt 5.8, 7.5, and about 40 million years ago. The team also revealed the sources of other types of meteorites; with this research, the origin of more than 90% of meteorites has now been identified. This discovery is detailed in three papers.

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"While more than 70,000 meteorites are known, only 6% had been clearly identified by their composition (achondrites) as coming from the Moon, Mars, or Vesta, one of the largest asteroids in the main belt. The source of the other 94% of meteorites, the majority of which are ordinary chondrites2, had remained unidentified.

"Why are these three young families the source of so many meteorites?

"This can be explained by the life cycle of asteroid families. Young families are characterised by an abundance of small fragments left over from collisions. This abundance increases the risk of collisions between fragments and, coupled with their high mobility, their escape from the belt, possibly in the direction of Earth. The asteroid families produced by older collisions, on the other hand, are "depleted" sources of meteorites. The abundance of small fragments that once made them up has naturally eroded and finally disappeared after tens of millions of years of successive collisions and their dynamic evolution. Thus, Karin, Koronis and Massalia will inevitably coexist with new sources of meteorites from more recent collisions and eventually give way to them.

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"Thanks to this research, the origin of more than 90% of meteorites has now been identified. It has also enabled scientists to trace the origin of kilometre-sized asteroids (a size that threatens life on Earth). These objects are the focus of many space missions (NEAR Shoemaker, Hayabusa1, Chang'E 2, Hayabusa2, OSIRIS-Rex, DART, Hera, etc.). In particular, it appears that the asteroids Ryugu and Bennu, recently sampled by the Hayabusa2 (Japanese Aerospace Exploration Agency JAXA) and OSIRIS-REx (NASA) missions and studied in laboratories around the world, particularly in France, are derived from the same parent asteroid as the Polana family."

Comment: the more we learn is vital. The big ones, kilometer-size, are every dangerous to us. Maybe God is not so perfect at all! OR, this is the way it had to be as we see in the issue of why life has so many problems. Can there be limits God cannot traverse?