Overview
- A peer-reviewed Nature Astronomy study reports that Earth's building blocks came from the inner solar system with outer input likely below two percent.
- The ETH Zurich team reanalyzed ten isotope systems in meteorites using specialized statistics to compare Earth's makeup with known solar system reservoirs.
- The result supports a scenario where early Jupiter opened a gap in the protoplanetary disk that blocked most outer material from moving inward.
- If the solids were local, water and other volatile elements must have been present in the inner disk during Earth's growth rather than delivered later from afar.
- The authors plan tests of inner-disk water supply and comparisons to exoplanet systems, noting that checks on Venus and Mercury await direct rock samples.