It would appear that the so-called "great instability" event that wreaked chaos among the planets, sending the gas giants careening through space until they settled into the orbits we know today, occurred between 60 and 100 million years after the birth of the solar system . This is the conclusion of some careful scientific detective work that has connected a type of meteorite to an asteroid that was once pushed around by those marauding planets.
Thanks to studies of the compositions and locations of various types of asteroids and comets , scientists know the aforementioned carnage occurred early in the history of the solar system. Still, there are some puzzles yet to be solved when it comes to how exactly everything went down.
For instance, scientists are aware that the objects in the solar system we see today, including Earth, formed around the sun from a disk of gas and dust. However, some of those objects, namely asteroids and comets, appear to consist of material that was not present in the disk ⁘ at least, the material shouldn't have been present in the locations those objects currently find themselves in. Instead, it'd make more sense for these items to have formed closer to the sun before being scattered farther afield. If Jupiter and the other giant planets migrated from where they formed , maybe asteroids and comets could've as well.
"The idea of this orbital instability is now well established in the planetary community, however the time at which this instability occurred is still a matter of debate," planetary scientist Chrysa Avdellidou of the University of Leicester told Space.com.
The team focused on a kind of meteorite called an EL enstatite chondrite, which has a low iron abundance and is very similar in composition and isotopic ratio to the material that formed Earth. This tells scientists that Earth and EL chondrites likely condensed out of the same part of the planet-forming disk.
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