Water is abundant on our planet and plays a crucial role in the existence of life on Earth. For a long time, scientists were puzzled by the way in which the water appeared. Some argued that it was brought by traveling comets that crashed into the planet, while others thought that it appeared during the formation of the planet.
A new study elaborated by a team of researchers argues that most of the water came from the original building blocks which formed the planet. The results are based on the analysis of ancient meteorites.
An analysis of meteorite samples revealed that only 2% of the meteorites that made it to the surface could be classified as enstatite chondrite meteorites. Their chemical structures are similar to the rocks which formed Earth more than 4.5 billion years ago.
The main information sought by researchers was the amount of hydrogen present in the meteorites, as the element is essential for the formation of water. Since Earth formed closer to the sun in comparison to other planets, some scientists thought that high temperatures might have prevented the formation of ice water.
Before the new study, there were little to no measurements related to the presence of hydrogen or water in the meteorites, which were analyzed. Some measurements were made, but the meteorites which were used could have been affected during the fall to the surface.
The amount of hydrogen which was observed is lower than what can be found in standard meteorites, but it can explain the massive amount of water that surfaced on the planet before the oceans formed. Additional measurements of the deuterium-to-hydrogen ratio reinforce the fact that the building materials played an important role in the formation of water. More water could have arrived from other sources, according to the team.
A paper was published in a scientific journal.