New study reveals half of Earth's water is older than the Sun BEC CREW FRIDAY, 26 SEPTEMBER 2014 Half the water on Earth and much of the water in the Solar System is older than the Sun, astronomers have discovered. This new finding, led by Ilsedore Cleeves from the University of Michigan in the US, suggests that our water is significantly older than we’d ever imagined, and that water should be plentiful in other planetary systems too. The discovery was made through the use of new computer simulations, developed by Cleeves and her team, of the early Solar System. “While we can't go back in time to see the Sun and Solar System at its formation, the wonderful thing about the vastness of the galaxy is that we can observe many other young Sun-like stars that are currently forming or have recently formed,”Cleeves told Becky Ferreira at Motherboard."By studying these astrophysical objects using high power
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8/11/2019 New study reveals half of Earth's water is older than the Sun
FRIDAY, 26 SEPTEMBER 2014Half the water on Earth and much of the water in the Solar System is older than the Sun, astronomers have discovered.
This new finding, led by Ilsedore Cleeves from the University of Michigan in the US,suggests that our water is significantly older than we’d ever imagined, and that watershould be plentiful in other planetary systems too.
The discovery was made through the use of new computer simulations, developed byCleeves and her team, of the early Solar System.
“While we can't go back in time to see the Sun and Solar System at its formation, thewonderful thing about the vastness of the galaxy is that we can observe many other youngSun-like stars that are currently forming or have recently formed,” Cleeves told BeckyFerreira at Motherboard. "By studying these astrophysical objects using high power
telescopes and numerical techniques, we can use this information to model theprotoplanetary disk environment in great detail.”
The protoplanetary disk environment is where planets form. Containing large amountsof dust and gas particles that resulted from the collapse of an interstellar star-foundingcloud, the protoplanetary disk and the new star next to it will rotate together, and the debrissurrounding the disk will form new planets.
Publishing their results in the journal Science today, Cleeves and her team modelled
the ‘heavy water’ in ice that was floating in the protoplane tary disk that formed our SolarSystem. Heavy water contains an isotope of hydrogen called deuterium, and it’s found inall water in the Solar System, including that on planets, icy moons, and inside comets andmeteorites.
The team simulated how much heavy water would have formed during the birth of theSolar System to find that it was much less than expected. So then they wanted to figureout if the high levels of deuterium found in this water was passed on from preexistinginterstellar gas, or if it was the result of chemical reactions from the protoplanetary disk asits debris formed several planets.
“The short answer was that disks did not synthesise heavy water in abundance, and so
could not have been the original source of our water,” Cleeves told Ferreira. “This workimplies that much of the Solar System's water ice was inherited from the original birthenvironment of the Sun in very dark, cold interstellar gas.”
"In other words, much of the water that flows on Earth is older than the planet itself, aswell as its host star. Its a mindboggling notion, especially when extended to otherexoplanets and stars,”says Ferreira at Motherboard.
According to Aviva Rutkin at New Scientist, the team calculates that half the water onEarth and maybe all of the water found in comets came from this ancient source.The team will continue their investigation, looking into what else might have been deliveredby materials that existed before the Solar System’s formation.
