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"I am curious about what effect an asteroid impact, like the one that killed the dinosaurs, would have on the orbit of the earth."
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Photosynthesis in the late Archean
A new study on carbon isotopes in sedimentary rocks from Western Australia by researchers from NAI’s Penn State and Carnegie Institution of Washington Teams supports the idea that small, shallow pools of water containing photosynthetic microbes existed on the early Earth ~ 2.72 Gya, about 300 million years before the rise of oxygen in the atmosphere. Their findings suggest a “global-scale expansion” of these habitats, and a progression away from anaerobic ecosystems and toward photosynthetic communities before the oxygenation of the atmosphere. This work was published in the early edition of this week’s PNAS.
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