Much of the water on Earth was present before the cataclysmic collision between two planets, which led to the formation of the Moon, according to an international team of scientists.
The impact between Earth and the other planet would have occurred some 100 million years after the formation of our solar system, which would mean about 4.6 billion years ago.
According to the theory presented by an international team of scientists, most of the water would not have appeared on Earth as a result of the impact of small asteroids or comets, as previously thought. In fact, according to this study, only less than 30% of the water could have reached the Earth after the collision.
The British researcher Richard Greenwood and his colleagues believe that liquid water can survive giant collisions and that it could be abundant on exoplanets. A reality that increases the likelihood of finding life forms beyond our system, according to them.
The water on the Earth could’ve existed before the collision with another planet which led to the formation of the Moon
Nonetheless, the water on the Moon, allegedly discovered earlier this year in large amounts, could’ve reached to the lunar surface through the collision which formed our natural satellite.
The researchers compared the oxygen composition of lunar rocks, from NASA’s Apollo missions on the Moon, with the volcanic rocks of the ocean floor on Earth and they only detected a small difference between lunar rocks and terrestrial rocks.
“Our analysis showed a difference of 3 to 4 parts per million between isotopic oxygen concentrations of lunar rocks and terrestrial basalts, but no significant difference between lunar samples and terrestrial olivine, a common mineral in the subsoil earthly. It shows the great efficiency of the mixing between the two planets during the collision, and places landmarks on the materials that could reach the Earth later,” explained Richard Greenwood.
If most of the water on Earth had appeared after the collision, the oxygen composition of the lunar and terrestrial rocks would be significantly different. This suggests that the liquid water on the Earth must exist at an earlier stage, before the Earth collision with another planet, which led to the formation of the Moon.