Friday, November 04, 2005

Whoa! Missed this one:

Volcanoes ruled out for Martian methane

"I can't rule out a geological source of methane" because there are many conceivable mechanisms, Krasnopolsky told New Scientist, but "this makes biological methane more plausible".

3 comments:

W.M. Bear said...

I'm starting to wonder about the implications finding current life on Mars would have for the hypothesis that there a ruins of artificial structures on Mars? Personally, I'm inclined to believe that life would have to have originally evolved when conditions were much more hospitable to life (oceans or seas, a thicker, warmer atmosphere, etc.) These conditions would only need to have persisted for around 500 million years (the length of time multicellular organisms have populated the Earth) in order for intelligent life to arise. If Mars was "front loaded" and had these habitable conditions almost from the start, complex life could have evolved there much more quickly than on Earth, which was basically uninhabitable for multicellular orgranisms for nearly 90% of its lifespan. There would still then be plenty of time (billions of years, in fact) for Mars to "decline" from the original "Martian Spring" to what we see now. (And for the ancient Martians to build their mighty starship engines and....)

Mac said...

Of course, the "Martians" could have been passing through from somewhere else...

W.M. Bear said...

Yeah. There's really no way to tell from where we are now. I'm kind of partial to BOTH ideas, actually. If the ancient Martians DID arrive from elsewhere, though, they must have settled Mars instead of Earth either:
A) Because they were from a low-gravity home planet themselves....
OR
B) Earth was at the time of their arrival uninhabitable. This possibility is interesting because it gives us a way of very roughly "dating" about the latest they could have arrived, which would have been roughly 500 million years ago, when Earth became habitable to multicellular organisms, after possibly a long period as "Snowball Earth" during which most of the water was apparently locked up in the form of a planet-wide Ice Age (to say nothing of the scarcity of oxygen in the air plus too much methane).

Or both A & B. My main argument against interstellar settlement, though, is the nature of some of the large-scale anomalies such as the Face and the D&M; pyramid. It's not clear to me why, if the ancient Martians ALREADY possessed star-travel technology they would build megalithic structures typical of a much earlier phase of civilization. I know from your speculations and those of others it's possible that these structures were actually arcologies of some kind, but still....