Does Our Water Really Come From Outer Space?
Photo via Maryanne Ventrice via Flickr CC
The theory generally goes that our water is the result of chemical reactions created when our planet was in its formation stage. However, a new theory poses that our water was actually a chemical hitchhiker, finding a home on Earth after being brought here as ice on incoming meteors. And it could have been receiving just the right amount from space that sets Earth apart from our dry sister planets.Francis Albarède of the Laboratoire des Sciences de la Terre published an article in the journal Nature late last month that proposes, "that the Moon and the Earth were essentially dry immediately after the formation of the Moon--by a giant impact on the proto-Earth--and only much later gained volatiles through accretion of wet material delivered from beyond the asteroid belt."
In other words, water came quite a bit after the formation of the planet, via icy rocks from outer space.
Science Daily reports, "According to books, the ocean and the atmosphere were formed from volcanic gases and the Earth's interior is the source of volatile elements. However, the rocks of the Earth's mantle are deficient in water (geochemists estimate its concentration at two hundredth percent). The same is true on Earth's sister planets, Venus and Mars. The main reason proposed by Albarède is that, during the formation of the Solar System, the temperature never dropped sufficiently between the Sun and the orbit of Jupiter for volatile elements to be able to condense with planetary material. The arrival of water on Earth therefore corresponds to a late episode of planetary accretion."
And further, receiving the water started plate tectonics, which started life on Earth. Albarède proposes that the delivery of volatile elements to Earth was part of the largest planets in the solar system pulling ice-rich chunks of space rubble into their gravitational fields, and our planet was one recipient. Once water arrived, it helped to loosen up the planet's mantel, leading to plate tectonics, continents, and conditions that helped life get rolling.
So water, and therefore life on Earth, might be here only thanks to gravity and some crash-landing rocks.
More Cool Connections Between Space and Water
Can A Billionaire Clown Help the Water Crisis from Space?
Clearing Space Junk from Earth's Orbit By Launching Water At It?
Could the Moon Be the Answer to Our Water Woes?