Some planets might produce their own water instead of relying on outside sources.
In laboratory experiments, researchers simulated extreme conditions found within certain exoplanets by blasting olivine — a mineral abundant in planetary interiors — with high-energy lasers in the presence of hydrogen gas. Hydrogen strips the minerals of their oxygen atoms, which then react with the hydrogen to form water, the team reports October 29 in Nature.
The discovery offers a viable explanation for water-rich exoplanets orbiting close to their host stars, the researcher say. The process might even account for the origin of some of Earth’s water, adding a new piece to a longstanding mystery.