Researchers say they discovered evidence that early Earth was home to more hydrogen than previously thought, calling into question widely held beliefs about the origins of water and the planet’s evolution.

All that said, the findings can’t confirm the terrestrial life theory beyond a doubt. There’s still a chance hydrogen-heavy meteorites helped us along. Still, the new evidence makes a strong case that ancient Earth had the ability to form water all on its own—no space rocks needed.

A team of researchers at the University of Oxford have uncovered crucial evidence for the origin of water on Earth. Using a rare type of meteorite, known as an enstatite chondrite, which has a composition analogous to that of the early Earth (4.