Sulfur was key to the first water on Earth

The find suggests all rocky planets get wet soon after birth, boosting the chances for life

Earth ocean

Although Earth formed in a hot, dry region around the newborn sun, hydrogen survived inside the sulfur-bearing mineral pyrrhotite and later joined oxygen to create water on our world.

S.Cristoforetti/ESA, NASA (CC BY-NC-SA 2.0)

A chemical element that’s not even in H2O — sulfur — is the reason Earth first got its water, a new study finds, bolstering a similar claim made a year ago.