When it arose, Earth was not as calm blue as the oceans it seems today, but a huge mass of extremely hot magma, before gradually cooling down over tens of millions of years and forming the atmosphere and oceans appearing. Where did all that water come from?
In a new scientific study recently published in the journal Nature, a group of researchers presented a new hypothesis that the water on the planet's surface was formed as a result of interactions between Earth's ancient atmosphere and the magma that covered its surface early after its creation.
Various hypotheses
Two hypotheses about the source of Earth's water are common in the scientific community, according to the website of the SciTech Institute in Arizona. The first assumes that water on Earth, or a large part of it, came to it from space early after it formed.
At the time, the Earth was smaller, making its way into orbit amid a large number of chaotic objects orbiting the sun, and meteorites and icy comets collided with the fledgling planet to carry water to it. This water then deposited on the surface over time forming the oceans.
Meteorites that hit Earth early after they formed may be the source of water, according to one hypothesis (NASA)
The second hypothesis suggests that most of Earth's water was already inside the planet, and it surfaced over time. It says that elements of some of the wet materials that contain water are found inside the cloak of the earth, in an area between the upper and lower mantle.
When hot magma rises from below and cold magma descends from above, it exerts great pressure on these materials, crushing them and then squeezing them like sponges. During this process, water finds its way to the surface through volcanoes and underwater vents.
But in recent years, the study of exoplanets far from the solar system has made it possible to deepen knowledge about the different interactions that could occur in Earth's atmosphere when it was forming, allowing scientists to develop new theories about the formation of water on Earth.
The new hypothesis is that water was formed from reactions that occurred early after the formation of the Earth (Pixaby)
From the ground
In the recently published study, researchers from the Carnegie Endowment for Science and the University of California, Los Angeles presented a different hypothesis about where the water on Earth comes from. The hypothesis says that water was formed from interactions that occurred early after the formation of the Earth, between the atmosphere and the magma oceans that cover the surface of the planet.
According to a press release published on the Carnegie Institution for Science website on April 12, researchers demonstrated that early in Earth's existence, interactions between the magma ocean and the hydrogen-rich protoatmosphere could have led to the emergence of some distinctive features of the Earth, such as the abundance of water and its overall oxidative state.
The researchers revealed that even if all the rocky material that collided to form the growing planet were completely dry, these interactions between the molecular hydrogen atmosphere and the magma ocean would generate copious amounts of water.
But the study's authors say other hypotheses about where water comes from on Earth are still possible, but they are not enough to explain the presence of all this amount of water on our planet. Their findings only provide a possible explanation for the evolution of our planet, but they establish an important link between the history of Earth's formation and the most common exoplanets discovered orbiting distant stars.