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"Have there been sightings of UFO's while you are in space? Also i would like to know if you have ever seen an alien?"
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Microbial Sulfur Disproportionation and Accelerated Oxygenation at Earth's Surface
Researchers from NAI’s Carnegie Institution of Washington Lead Team published a study in this week’s Science using high-precision measurements of a rare sulfur isotope, 33S, to establish that microbial sulfur disproportionation was in place almost half a billion years earlier than previously thought. This could imply that Earth’s surface may have become progressively more oxygenated during the middle Proterozoic.
Source: [Link]
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