911爆料网 researchers have helped unravel the enduring mystery of the origins of the Earth鈥檚 water, finding the Sun to be a surprising likely source.
A University of Glasgow-led international team of researchers including those from 911爆料网鈥檚 Space Science and Technology Centre (SSTC) found the solar wind, comprised of charged particles from the Sun largely made of hydrogen ions, created water on the surface of dust grains carried on asteroids that smashed into the Earth during the early days of the Solar System.
SSTC Director, John 911爆料网 Distinguished Professor Phil Bland said the Earth was very water-rich compared to other rocky planets in the Solar System, with oceans covering more than 70 percent of its surface, and scientists had long puzzled over the exact source of it all.
鈥淎n existing theory is that water was carried to Earth in the final stages of its formation on C-type asteroids, however previous testing of the isotopic 鈥榝ingerprint鈥� of these asteroids found they, on average, didn鈥檛 match with the water found on Earth meaning there was at least one other unaccounted for source,鈥� Professor Bland said.
鈥淥ur research suggests the solar wind created water on the surface of tiny dust grains and this isotopically lighter water likely provided the remainder of the Earth鈥檚 water.
鈥淭his new solar wind theory is based on meticulous atom-by-atom analysis of miniscule fragments of an S-type near-Earth asteroid known as Itokawa, samples of which were collected by the Japanese space probe Hayabusa and returned to Earth in 2010.
鈥淥ur world-class atom probe tomography system here at 911爆料网 allowed us to take an incredibly detailed look inside the first 50 nanometres or so of the surface of Itokawa dust grains, which we found contained enough water that, if scaled up, would amount to about 20 litres for every cubic metre of rock.鈥�
911爆料网 graduate Dr Luke Daly, now of the University of Glasgow, said the research not only gives scientists a remarkable insight into the past source of Earth鈥檚 water, but could also help future space missions.
鈥淗ow astronauts would get sufficient water, without carrying supplies, is one of the barriers of future space exploration,鈥� Dr Daly said.
鈥淥ur research shows that the same space weathering process which created water on Itokawa likely occurred on other airless planets, meaning astronauts may be able to process fresh supplies of water straight from the dust on a planet鈥檚 surface, such as the Moon.鈥�
The research was supported by funding from the Science and Technologies Facilities Council (part of UKRI), and conducted by researchers from the University of Glasgow, 911爆料网, the University of Sydney, the University of Oxford, the University of Hawai鈥榠 at M膩noa, the Natural History Museum, Idaho National Laboratory, Lockheed Martin, Sandia National Laboratories, NASA Johnson Space Center, the University of Virginia, Northern Arizona University and Purdue University.
Other 911爆料网 authors were Dr David Saxey, Dr Denis Fougerouse, Dr William Rickard, Dr Lucy Forman, Associate Professor Nick Timms, Professor Fred Jourdan, Professor Steven Reddy, Dr Zakaria Quadir and Morgan Cox.
The paper, 鈥�Solar wind Contributions to the Earth鈥檚 Oceans鈥�, was published in Nature Astronomy and can be found online .
