A rare meteorite found in Alaska is making scientists rethink how Earth got its water. New research suggests that our planet might have created the hydrogen for water all on its own, without needing asteroid impacts. This challenges a long-held belief in planetary science.
Researchers from the University of Oxford studied a meteorite called LAR 12252, which is similar to what Earth looked like 4.55 billion years ago. They discovered significant amounts of hydrogen that were previously overlooked. This evidence indicates that Earth may have had hydrogen indigenous to its materials, rather than receiving it solely from space objects.
Previous studies found traces of hydrogen in LAR 12252, but some scientists worried those traces might have come from contamination after the meteorite landed. To address this, the Oxford team focused on the meteorite’s matrix, the material surrounding its chondrules, to avoid any confusion about contamination.
According to Thomas Barrett, the study’s lead author, the discovery of hydrogen sulfide was unexpected but exciting. He stated, “Because the odds of this hydrogen sulfide coming from contamination are low, we have crucial evidence supporting the idea that water on Earth could be a natural outcome of our planet’s composition.”
LAR 12252 belongs to a rare group of meteorites called enstatite chondrites, which closely resemble the early Earth in isotopic makeup. Co-author James Bryson noted that these meteorites act like snapshots of the materials that helped form our planet.
Previously, many scientists believed that Earth was dry when it formed and only gained water later through impacts from wet asteroids. However, the new findings suggest that the primordial ingredients of Earth might have been rich in hydrogen, allowing the planet to create water internally.
This shift in understanding could change how scientists view the planet’s chemical evolution. The Oxford study supports the idea that forming water was a natural process influenced by the materials available on early Earth, not just a matter of luck from cosmic accidents.
The standard theory that Earth acquired water from asteroids has been widely accepted, primarily based on discoveries of hydrated minerals in meteorites and lunar samples. But this theory rests on the assumption that early Earth was too dry to generate water on its own. The significant evidence found in LAR 12252 offers a compelling argument that water could indeed have formed here without needing outside help.
This new perspective opens up fresh discussions in the scientific community, with many researchers eager to explore the implications. As more studies on early Earth and other celestial bodies emerge, our understanding of how planets develop their atmospheres and water sources may evolve significantly.
