Ancient water 4.6 billion years hidden thousands of kilometers underground

Scientists for the first time found water molecules at the time of new Earth formation about 4.6 billion years ago under a depth of 2,900km in the ground.

Found the oldest water molecule on Earth

According to Live Science, about 4.6 billion years ago, the Earth was formed from the multitude of collisions of dust and rocks around the Sun. Planetary scientists at the University of Hawaii hypothesize that ancient minerals hidden below 2,900 kilometers of the Earth's surface, may contain the first water molecules. They searched for a lava from 1985, on Baffin Island in the Canadian Arctic, at that depth to find the answer.

After obtaining lava from deep shells, they began to search for traces of water molecules that were not impure in basalt, the rocks that formed when lava cooled.

The key to finding the origin of water comes from hydrogen, more precisely the ratio of hydrogen between two types of isotopes: a type of neutron-free nucleus, usually named hydrogen, while the other has a neutron, called is deuterium . This ratio is unique to each planet, meteorite and comet in the solar system. More often, objects closer to the Sun will have more hydrogen in the water molecule; on the contrary, the more deuterium the more Sun will be.

Previous studies on Earth's surface water indicate that deuterium has a high rate. These results lead to the hypothesis that water on Earth comes after it forms, from meteorites or comets that have lots of water, from outside the solar system.

Baffin Island, where research lava samples are taken.(Photo: Ansgar Walk).

However, according to new research, dust samples deep below the Earth's surface for billions of years show more hydrogen in water molecules than deuterium. This means that saturated dust has mixed in the rocks that form the Earth.

According to Lydia Hallis, the lead author of this study, the exact depth is very important. The study is published in the journal Science on November 12.

"We need a specimen that is not affected by Earth's formation , " she said. She is a planetary scientist at Glasgow University. The surface of the Earth has a huge change after billions of years, but lava in deep shells remains unchanged from the time of Earth's formation. Lava near the surface may have erupted and mingled with substances on the surface.

In addition, in the process of searching for primitive water , she and her colleagues had to make sure that the minerals analyzed were Earth's right after forming, without impurities from lesser age rocks. This is really a challenge.

"Hydrogen is everywhere on this planet. It is difficult to say that the hydrogen you are analyzing is not hydrogen from impurities. It took us years to make sure we did not analyze water from the left surface. Land, " she said.

"This study changes everything , " commented Steve Desch, an astronomer and professor at Arizona State University, USA.

"Discussions about the origin of water on Earth for decades have focused on the hypothesis that water comes from meteorites or comets. This study shows that dust and gas around the Sun is also a closed source. Significant contributions suggest that it is necessary to reassess previous conclusions when ignoring the role of the so-called " solar nebula" .

According to Desch, this study also helps decode the process of formation and disappearance of water over time on other planets in the solar system, and possibly planets of other distant star systems.

"A new chapter in understanding the process of forming water on planets like Earth has begun."