Earth has three parts water and one part land — even so, scientists have still not been able to totally agree on a theory about how this water came to be.
A new paper by Arizona State University researchers states that the water on earth was formed by material and gas brought by asteroids along with left over gas from the formation of Sun.
This study can tell us a lot about how planets are formed and their potential to support life.
Most of Earth is covered in water but we still don’t know the origin of water for sure.
Asteroid water and comet ice are not the only possible water sources
Researchers noted that since comets contain a lot of ices, it could have supplied some water. Asteroids, which are not as water-rich yet still plentiful, could be a source as well.
Asteroids being Earth’s water source during the earliest days of its formation is not a new concept. It has been proven in previous studies that water sources created that early could have survived through all the heated remodelling the blue planet went through.
In fact this is the easiest explanation as the chemical signatures found in Earth’s water are the same ones found in the water on asteroids.
However, the hydrogen found in Earth’s water is not the exact same kind of hydrogen found in other parts of Earth — especially near its source. This suggest that asteroids were probably not the only source.
“But there’s another way to think about sources of water in the solar system’s formative days,” said Peter Buseck, Professor at the Arizona State University.
“Because water is hydrogen plus oxygen, and oxygen is abundant, any source of hydrogen could have served as the origin of Earth’s water,” Buseck added.
Earth went through many rapid changes at the time of its formation.
So, where did Earth’s water-making hydrogen come from?
The study challenges widely-accepted ideas about hydrogen in Earth’s water by suggesting the element partially came from clouds of dust and gas remaining after Sun’s formation — called the solar nebula.
If the abundant hydrogen in the nebula could combine with Earth’s rocky material as it formed, that could be the ultimate origin of Earth’s global ocean, the researchers said.
This is supported by recent research which states that solar nebula gas could have co-existed with growing planets which would give hydrogen the chance to incorporate itself into the deepest parts of the planets.
“The solar nebula has been given the least attention among existing theories, although it was the predominant reservoir of hydrogen in our early solar system,” said lead author Jun Wu, an assistant research professor at the varsity.
How can this new study help us better understand the birth of planets?
The new finding fits neatly into current theories of how Sun and the planets formed. Instead of trying to explain the origin of all of earth’s water with a single source, the study also takes into account multiple factors that could have caused such a big change.
It also has implications for habitable planets beyond the solar system as this finding says that even if planets are far away from water-rich asteroids, they could still hold water. This in turn means that the formation of habitable planets is not as much of a time-taking process as predicted before.
The formation of habitable planets is not as much of a time-taking process as predicted before.
Astronomers have discovered more than 3,800 planets orbiting other stars, and many appear to be rocky bodies not greatly different from our own.
The research team is trying to gather more data samples from Earth’s mantle to support the new study and also moving forward with lab experiments to understand the chemical processes in greater detail as they might have occurred in atmosphere conditions existing in early Earth.
(With inputs from IANS)