What if Earth’s water fell from the sky?
I read a fascinating article written by Serge Brunier in the February edition of Science et Vie magazine wherein Brunier questions a preconceived idea. The notion that during Earth’s formation, water was put into the atmosphere during magma fusion, resulting in torrential rains is an idea that many scientists reject. Rather, they believe that Earth’s water supply came by comets and asteroids during a period that lasted millions of years.
Francis Albarède, Geochemistry professor at the Ecole Normale Supérieure in Lyon, stated in an October 2009 Nature article that “There was no water on Earth at its beginning, it was brought by comets and asteroids much later”, this analysis was confirmed by English and American geologists who published similar findings in the review Science. The classic explanation for Earth’s waters has become increasingly questionable in light of recent research, which indicates that in the beginning Earth was as dry as the Moon (this is due to the low presence of sulfur and lead in its core). It seems that indeed, water arrived by asteroids some 100 million years after Earth’s formation.
The arrival of an enormous amount of water created a geological process that is unique to the rest of the solar system: plate tectonics. The water penetrated Earth’s terrestrial mantle, making it mobile and allowing for continental drift and for subsequent evolution of life. This evolution is celebrated in the movie La Planète Bleue (“The blue planet”), check out the below clip. While we don’t know whether or not the Gods blessed Earth’s waters we have no doubt that they were heaven sent!