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Earth's Water Didn't Come From Outer Space

Posted by Soulskill on from the no-word-on-elvis dept.

sciencehabit writes "Where did Earth's oceans come from? Astronomers have long contended that icy comets and asteroids delivered the water for them during an epoch of heavy bombardment that ended about 3.9 billion years ago. But a new study suggests that Earth supplied its own water, leaching it from the rocks that formed the planet. The finding may help explain why life on Earth appeared so early, and it may indicate that other rocky worlds are also awash in vast seas."

2 of 181 comments (clear)

  1. it would be too nice to be true by Anonymous Coward · · Score: 5, Insightful

    If this is true, then most earth sized rock planets in the habitable zone are also having water by default. Whoa, this simplifies the drake equation.

  2. It is just way more complicated actually by Framboise · · Score: 4, Insightful

    The water we drink must have been reprocessed many times for eons by living beings.
    Remember that the amount of sedimentary rocks made of dead stuff is much larger than
    the total of oceans. This implies that striclty speaking each molecule has been dissociated
    and recombined with different oxygen and hydrogen atoms. Many O and H atoms now in
    water have been in other compounds (CO, H2SO4, ...) for a while and vice versa.