Scientists have found that oxygen and the life that generates it might have enriched the Earth far earlier than currently supposed. Muzi.com News 10018490-0 (muzi.com)
The discovery, sure to be controversial, suggests life could arise earlier than now thought on alien planets, too. Muzi.com News 10018490-1 (muzi.com)
Currently, scientists widely believe photosynthetic microbes helped oxygenate the planet roughly 2.4 billion years ago, and that oxygen was scant in the atmosphere before then. They base this idea on isotopes of sulfur in ancient rocks. Isotopes of sulfur all behave virtually the same chemically but have slightly different masses
Read full
newshere