|Meteorites on their way to earth and breaking through atmosphere.
Elements of this image furnished by NASA- earthmap for 3Drender
A key mystery about the origins of Earth’s water may have been solved after an international team of scientists uncovered persuasive new evidence pointing to an unlikely culprit—the Sun.
In a paper published in Nature Astronomy, a team of researchers, including two from the University of Hawaiʻi at Mānoa School of Ocean and Earth Science and Technology (SOEST), describe how analysis of dust grains from the surface of an ancient asteroid suggests that extraterrestrial dust grains from asteroids and comets carried water to the surface of the early Earth. The water in the grains is produced by space weathering, a process by which charged particles from the Sun, known as solar wind, altered the chemical composition of the grains to produce water molecules.
The finding could answer the longstanding question about the sources of the water that covers 70% of Earth’s surface—far more than any other rocky planet in our Solar System. Planetary scientists have been puzzled for decades over the source of Earth’s oceans. One theory suggests that comets and asteroids brought the water to the planet in the final stages of its formation 4.6 billion years ago.