The origin of water on earth since long has been main topic of several scientific discussions. Now researchers in a study have presented new evidence of how water actually came on earth.

So far there has been a long list of theories for how water came to earth, but scientists are not sure whether earth formed with water molecules on it or those molecules arrived on earth later.

According to the new study, grains of dust rich in H2O that helped to form the planet were able to hold the liquid water at the time of the birth of earth.

The researchers said that in order to find the evidence for the ancient water they had to find the most pristine samples of an infant Earth. Scientists were lucky enough to find such sample which was volcanic rocks that were taken from the arctic Baffin Island in 1985.

Lead study author Lydia Hallis, a researcher at the University of Glasgow, said, “On their way to the surface, these rocks were never affected by sedimentary input from crustal rocks, and previous research shows their source region has remained untouched since Earth's formation”.

As per researchers the volcanic rocks they took as samples for their study are some of the most primitive rocks they’ve ever found on the surface of earth. As these rocks are quite old the water they contain helped to provide them some really crucial insight into the early history of earth. The data collected also helped them to know how the water actually arrived on earth.

The researchers during the study looked for deuterium, a modified form of hydrogen that creates ‘heavy water’. They found water that was very poor in deuterium.

According to Hallis, this made their point more clear that water on earth came from the dust that formed our solar system's planets.