Methane on Mars – biological or geological origin?

[Hercules Rockefeller]

A team of NASA and university scientists has discovered 'substantial plumes' of methane floating through the atmosphere of Mars. The discovery indicates Mars is either biologically or geologically active.

So what do Sciforum members think? Biology or geology? Or maybe something else.

The Red Planet is Not a Dead Planet

Mars today is a world of cold and lonely deserts, apparently without life of any kind, at least on the surface. Indeed it looks like Mars has been cold and dry for billions of years, with an atmosphere so thin, any liquid water on the surface quickly boils away while the sun's ultraviolet radiation scorches the ground.

The situation sounds bleak, but research published today in Science Express reveals new hope for the Red Planet. The first definitive detection of methane in the atmosphere of Mars indicates that Mars is still alive, in either a biologic or geologic sense, according to a team of NASA and university scientists.

"Methane is quickly destroyed in the Martian atmosphere in a variety of ways, so our discovery of substantial plumes of methane in the northern hemisphere of Mars in 2003 indicates some ongoing process is releasing the gas," says lead author Michael Mumma of NASA's Goddard Space Flight Center. "At northern mid-summer, methane is released at a rate comparable to that of the massive hydrocarbon seep at Coal Oil Point in Santa Barbara, Calif."

http://science.nasa.gov/headlines/y2009/15jan_marsmethane.htm

http://antwrp.gsfc.nasa.gov/apod/ap090119.html

 

[John Connellan]

I would instinctively say geological

 

[draqon]

geological origin.

 

[Hercules Rockefeller]

I would instinctively say geological

Okay, but why? This link shows an image made spectroscopically using large ground-based telescopes of ppb methane in the Martian atmosphere. What would a similar image of the Earth look like? Is terrestrial atmospheric methane predominantly due to biology or geology?

 

[draqon]

the reason why its not biological is because its way too harsh of an environment on Mars in order for something to stay alive there.

 

[Hercules Rockefeller]

That’s not sound reasoning. The surface of Mars may be harsh (depending on your definition of “harsh”) but beneath the surface there is almost certainly liquid water, higher pressure, protection from radiation and warmer conditions. Some parts of Earth can throw up harsher conditions than are likely to be found in the Martian subsurface, and in every extreme environment on Earth (natural or man-made) there are bacteria that live there quite comfortably.

Further than that, bacteria have shown that they can withstand conditions harsher than even the Earth can throw up. Bacterial stowaways survived trips to the Moon and back on probes.

Mars was once a lot warmer and wetter than it is today. What’s to say that life didn’t arise back then and has continued on beneath the surface where it is protected from the harsher conditions that have developed on the surface since then?

I also seem to remember reading some botanists that said that even some terrestrial eukaryotes could withstand the present-day Martian surface, such as lichen.

 

[synthesizer-patel]

Deja vu anyone?

the short answer is that at this stage we can't rule out either possibility.

Methane is a very simple molecule and can be synthesized through both biotic and abiotic processes and there are extremophile bacteria here on earth that live or will thrive in all kinds of really nasty extreme environments that would make Mars look like a sunday school outing - here's a nice example - this sucker was found at the bottom of the Marianas trench and will live quite happily in Toluene FFS!!!!!

http://www.sciencedirect.com/scienc...serid=10&md5=736a3f39b77abe450199319d15fa4303

Whether or not the particular example cited by the OP turns out to be one or the other, I would not be at all surprised if extremophiles were found on Mars at some point

 

[John Connellan]

Okay, but why?

I have no idea why - that's why I said instinctively. Somewhere in my brain my subconscious worked out that all this methane is not caused by life that we will or will not find. Unfortunately, my conscious brain cannot argue why not.

You did only ask for an opinion though. Maybe someone else can explain why they think life did not cause this methane.