Mar 012017
 

And if this is confirmed, both the age and the fact that it’s a fossil, it’s really, really, REALLY old:

Earliest evidence of life on Earth ‘found’

These “fossils” aren’t of recognizable critters, but hematite filaments, which are the traces of life. The age is somewhere between 3.77 billion and 4.28 billion years.. If it’s on the older end, it’s really rather astonishing; the theorized collision of the early Earth with the hypothetical planet Theia, resulting in the creation of the Moon, is believed to have occurred about 4.5 billion years ago. This collision would have turned the entire surface of the planet into liquid hot magma, so it seems life *could* have arisen less than a quarter billion years after the Earth was a molten ball of fire.

 Posted by at 8:31 pm
  • se jones

    Spallation man spallation.
    Prior the whole surface turning into a magma ocean, relatively unscathed chucks ‘o rock go flying off at >escape velocity. To paraphrase my old friend Chris McKay “the inner planets have been swapping spit from the time of their creation”.
    So…rocks with the earliest biological goodies would have rained back down for millions of years, both here on Earth *and* onto Mars, and vise versa of course.

    “…The shock level in the spalls is low, typically half of the dynamic crushing strength of the rock”

    http://web.gps.caltech.edu/~sue/TJA_LindhurstLabWebsite/ListPublications/Papers_pdf/Seismo_1515.pdf

    https://youtu.be/WUKN_YF8tjA?t=44s

    • publiusr

      So–at a certain distance from the crater, you might find an old truck speeding past ISS from spallation? 😉

      • se jones

        >old truck speeding past ISS

        That paints quite a picture. Ford or Ram, a GM would never survive.

        No, I was commenting on the big Moon forming impact returning the Earth to a planet-wide molten magma ocean state, thus resetting the evolution of life back to zero, once things cool down again. However, current understanding of impact theory (and actual meteorites) shows how the interior of some rocks ejected can stay pristine and biological stuff can survive the trip through interplanetary space and back down. The caveat is: in the rock is too small, or stays in solar orbit long enough, galactic cosmic rays will eventually damage any large organic molecules.

        • publiusr

          he caveat is: in the rock is too small, or stays in solar orbit long enough, galactic cosmic rays will eventually damage any large organic molecules.

          Or–just maybe–allow a positive mutation…

          • se jones

            well now there’s an optimist!