Methane Survey Reveals Mars Is Far From 'Dead' 171
astroengine writes "The first planet-wide studies of methane on Mars — incorporating billions of measurements made by NASA's Mars Global Surveyor spacecraft — shows gas concentrations peak in autumn and plummet in winter. Scientists have found significantly higher methane concentrations in the Tharsis, Elysium and Arabia Terrae regions. Tharsis and Elysium are home to Mars' most massive volcanoes and Arabia Terrae has large quantities of subterranean frozen water. This indicates the gas could be generated by geological or biological activity. 'It could be geology or biology, but it is not coming from another source. There is a seasonal pattern, so it could only be a local origin,' Sergio Fonti, with Italy's Universita del Salento, told Discovery News."
OH COME ON (Score:2, Interesting)
Don't get me wrong, I like hearing about space updates. But it feels like there's been a ton of "there may be signs that may indicate signs of biological life from stuff we may or may not have overlooked before. Also? It might not be caused by a biological thing."
I want a "we found fucking life" article. Stop teasing me with this nonsense.
Re:Nice way to narrow it down. (Score:4, Interesting)
Both are big deals - Mars isn't believed to be geologically active, and life would be a massively interesting find for obvious reasons.
The seasonality rules out explanations like cosmic rays generating methane.
Re:Question? (Score:3, Interesting)
Maybe. Let's say it resembles a bacterium on Earth except for the fact that the one on Mars has organelles or other internal structural features that take a very long time to develop that are absent from the one on Earth (or vice versa). You can then say with some certainty that it wasn't contamination during the Space Age. If further samples indicated that the variation in DNA was so great that the most recent common ancestor to all of them was a few million years ago at the earliest, it's old enough to call it Martian life regardless of the ultimate source of organic matter.
Re:Nice way to narrow it down. (Score:3, Interesting)
Another source would include the possibility of freeze/thaw cycles. There is also another method suggested last year involving radiolytic H2reacting in a non-bioligic manner with CO2 dissolved in water. That process would be neither biological nor geological. There are other atmospheric/radiological possibilities too (such as UV interacting with the atmosphere).
Yet another method is one you throw out sarcastically. Last year, as I recall, there was a hypothesis put forth that meteorites released methane as they burn up on entry. They do, in fact. However, the problem with that hypothesis is that this source is not significant enough to account for the large volumes of Methane required to support the cycles shown in the data this report discusses (10kg/year compared to a couple hundred tons/year). Subsurface deposits melting were also proposed as a source.
So yes, that actually does narrow it down. It narrows it down very significantly, and further if you accept the hypothesis that Mars is a 'dead' planet geologically. "Geological processes" are not as broad as you seem to believe. Geology is a rather specific field. Mars is considered dead geologically. Thus, if you accept that all other sources of Methane have been eliminated you are left with the following two possibilities:
1) Biological - life of some sort
2) Mars isn't geologically dead, and it is a geological process.
Either result is pretty damned important. Though technically it could be a third option: Both.
Further, the bigger quandary isn't so much *how* it is produced, but why does the Martian air "lose" so much methane so quickly? It is removed from the atmosphere faster than the usual suspects.
Your analogy would work if rocks could be formed atmospherically, biologically, or radiologically.