Ever wondered as to the origin of the water we have on Earth? A new study conducted by researchers from the University of Hawaii suggests that water was present at the formation of our planet, and that our oceans did not necessarily come later from external sources such as comets. The paper is published in Science.
The researchers came to this conclusion after they analysed rocks from Baffin Island, Canada. These rocks, said to originate from the mantle of the Earth and having remained untouched, contain tiny water droplets shown to have the same composition as the water we currently have on Earth.
Water can exist in different forms as per its type of hydrogen atoms: normal water is made of oxygen and hydrogen atoms and heavy water consists of oxygen and deuterium atoms. According to previous research, comets have a greater ratio of heavy water to normal water. However, the researchers’ analysis shows that the rocks have a lower amount of deuterium.
The lead author of the study, Dr Lydia Hallis, explains in a statement to IFLScience that it is very unlikely for this water to have come from comets because the latter could not have been powerful enough to impact on the deep mantle to affect the composition of the latter’s rocks. Rather, their findings pertaining to the heavy and normal water ratio suggest that water was present on our planet from the very start at its formation and that water coming from external sources such as comets were not necessarily the origin of our oceans.