13 books
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13 voters
Astrophysics
“
Like the Great Oxidation Event, the Great Unconformity injected an enormous quantity of oxygen into the atmosphere through a massive and efficient subduction of organic carbon into Earth's mantle. When this event occurred, the oxygen quantity in Earth's atmosphere jumped from 1% or less up to 8%. Just before the time of the Cambrian explosion 543 million years ago, another major continental erosion event coupled with oceanic sediment subduction led to a jump in the atmosphere oxygen level from 8
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”
― Designed to the Core
― Designed to the Core
“
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives.
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”
― Pale Blue Dot: A Vision of the Human Future in Space
― Pale Blue Dot: A Vision of the Human Future in Space
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