In “Fossil find shows Martian life possible” (ABC News, August 22, 2011), Kate Kelland reports that the world’s oldest fossils to date have been found in Australia, pretty accurately dated to about 3.4 billion years ago:
“We can be very sure about the age as the rocks were formed between two volcanic successions that narrow the possible age down to a few tens of millions of years,” he says. “That’s very accurate indeed when the rocks are 3.4 billion years old.”
The fossils appear to be extremophiles utilizing sulphur, thus able to cope with an almost oxygen-free environment.
An investigator, on early Earth:
“It’s a rather hellish picture,” he says. “Not a great place for the likes of us. But for bacteria, all of this was wonderful. In fact, if you were to invent a place where you wanted life to emerge, the early Earth is exactly right.”
Martin Brasier doesn’t explain why it’s exactly right, but the thought seems to be: If Mars is similarly hellish, there must be life there.
“Could these sorts of things exist on Mars? It’s just about conceivable. This evidence is certainly encouraging and lack of oxygen on Mars is not a problem,” says Martin Brasier of Oxford University, who worked on the team that made the discovery.
So now, hellish environments are sources of hope, not disappointment, when looking for life? Oh yes, of course, galaxy full of exoplanets teeming with life.
Significantly, no one addresses the true conundrum lurking in the find: How soon life got started after Earth cooled. Where is the window for random evolution?
File under: Hope clings eternal, with “The Shroud of Turin makes way more sense than water on Mars