. A team of scientists from Hawaii and Glasgow explains why Earth has water. According to the authors, it has been long a topic of controversy as to where exactly Earth got its water. The authors have presented new compelling evidence in their paper that water is a vital part of Earth’s history since it was created from the accretion and dissolution of rock and dust more than 4.5 billion years ago. Around 71% a third of Earth’s surface are covered by water. Lydia Hallis (study leader), was originally at the University of Hawaii, but is now a Marie Curie Fellow at Glasgow. She and her colleagues used advanced ion microscope technology to analyse a group of rocks on Baffin Island in Nunavut, Canada, which is Canada’s largest and most populous island. Scientists were able to see tiny amounts of water in these rocks using the ion microprobe, a large-diameter secondary ion mass spectrumr (SIMS sector) instrument. It is housed at University of Hawaii. Hydrogen-to-deuterium ratio The hydrogen-to-deuterium ratio in the water provided them with valuable new clues regarding its origins. Deuterium (a stable hydrogen isotope) and hydrogen have atomic masses of 1 and 2. Hydrogen, however, has an atomic weight of 1. Researchers have found that water from different types of planet bodies in the Solar System has distinct hydrogen/deuterium ratios. Dr Hallis stated that the Baffin Island rocks had been collected in 1985,, and scientists took a long time to analyze them over the years. We now know they have a component of Earth’s deep crust. Previous research has also shown that their origin region remains untouched from the Earth’s creation. They are, in essence, some of the most primitive rock we have ever seen on the Earth’s surface. Their water gives us valuable insight into Earth’s past and origins. The protosolar nebula, which formed our Solar System’s planets 4.5 billion year ago from dust surrounding the Sun, is believed to be rich in water. The researchers found very little deuterium in water, which suggests that it wasn’t brought to Earth once it has been formed. It is more probable that the water molecules were transported on dust from the disk surrounding the Sun (protosolar Nebula), before the formation the planets. Over time this water-laden dirt was gradually drawn together to create planet Earth. Dr Hallis said: “Even though some water was lost to the surface due to evaporation during the heat of formation, sufficient survived to form the planet’s water.” This is an important discovery that we didn’t have technology for until a few years back. This area is an exciting one and we look forward to more research.” The authors of the Abstract published in the Journal concluded that “Such strongly negative numbers indicate the existence a component inside Earth’s innermost mantle.” Science. 13 November 350 795-797. DOI: 10. 1126/science.aac4834.
Earth was water-rich from its inception. It did not arrive from meteorites or comets
