Planetary scientists at ETH Zurich analyzed isotope data from meteorites and found evidence that the material forming Earth came almost entirely from the inner Solar System. Their analysis suggests that less than two percent of Earth’s mass, or perhaps none, came from the outer Solar System.
The finding changes the question of how Earth got its volatile ingredients, including water. It does not settle the planet’s origin story, but it gives researchers a sharper way to think about the young Solar System and the barriers that Jupiter may have created between its inner and outer regions.