|Zircon in Jack Hills, Australia's Narre Gneiss Terrane|
Image credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team
Zircon crystals—little time capsules preserving bits of Earth’s ancient past—have in our recent past given evolutionary scientists a whole new view of conditions on the early Earth. Previously thought to have been a Hadean hell of molten magma for a very long time, the early Earth is now seen in the light of zircon-trapped atoms as a place that cooled enough for water to condense within 160 million years of being spit out of a solar nebula and coalescing as a fiery ball. Now the discovery of flecks of graphite in an Australian zircon crystal has raised the possibility that life evolved very quickly in that ancient world, 300 million years earlier than previously thought.To read the rest, click on "Did Earth’s Earliest Life Leave Carbon Footprints in a 4.1 Billion-Year-Old Zircon?"