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Earth's Water Didn't Come From Outer Space

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."

5 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. Re:Um... by Zero__Kelvin · · Score: 4, Informative

    Um ... By definition, no.

    --
    Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
  3. 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.

    1. Re:It is just way more complicated actually by Taibhsear · · Score: 4, Funny

      pfft. Leave it to Oxygen to over react...

  4. Re:So... there is a God? by vivian · · Score: 4, Interesting

    Keep up, will you? The water, which is the lifeblood of living things, came out of stones.

    I wonder how much this removal of water from the rocks depends on the earth having a hot mantle? If the mantle were cooler, then the water would stay there instead of being cooked out as steam and being able to re-condense else where. This is massively speculative of course - but could part of the reason mars no longer has a liquid ocean be that since the planet has cooled now, all it's water is locked up back in the rocks again? Is the fact that we have a hot interior on our planet the main driving factor that allows us to have a liquid ocean?