Earth's water was present when the planet was formed, not added later by comets or asteroids, according to a new study of ancient rocks from deep inside the Earth's mantle.
The findings reported in the journal Science, provide new insights into the formation of terrestrial bodies throughout our solar system and beyond.
"Our measurements suggest that Earth had its water from the very beginning of its formation and the water originated from the proto-solar disk," study lead author Dr Lydia Hallis, of the University of Hawaii NASA Astrobiology Institute and the University of Glasgow, said.
The proto-solar disk was the cloud of molecular gas and dust from which the Sun, Earth and rest of the solar system were formed 4.6 billion years ago.
"Initially people thought that heat generated through the accretion process would make the early Earth very hot, boiling off all the original water, which was later replaced with water from comets and asteroids. But we found that's not the case," Dr Hallis said.To read more, click here.