Methane! On Mars! OMFG!
So here we go… again. Oh, and good day to you, or night, whatever.
There are rumors about that the Mars Rover Curiosity has found methane in the atmosphere of Mars and therefor we should freak out and get ready for an alien invasion.
Well let’s not. Instead, just read this blog post and we’ll suss it out together.
Click through to read more:
So the methane talk has begun and lots of people are messaging me for some reason asking what it means. First off, I don’t know – I’m not a scientist, and secondly – let’s do a science and find out.
Methane (CH4) is a short-lived compound, the main component of natural gas, and probably the most abundant organic compound on earth. It is a gas above -160 degrees Celsius, and is primarily created (on Earth) through methanogenesis – which is the breakdown of organic compounds by certain bacterias.
Now, because of this last bit the assumption is that finding methane on Mars would indicate the presence of LIFE – especially because methane cannot last in the Martian atmosphere due to ultraviolet radiation and chemical reactions – which would indicate that if there is methane on Mars, something must be replenishing it. That gets everyone’s knickers in twisty modes.
But what’s actually going on – and is it something amazing? Probably not (though possibly so).
First off – Methane on Mars HAS BEEN CONFIRMED by the Mars Express Orbiter in 2009 – at a level of 10 parts per billion – but what we don’t have is verification on the ground. Luckily, that’s one of the thing that the Sample Analysis at Mars (SAM) instrument on Curiosity is supposed to find out.
But let’s assume there IS methane on Mars. Does that mean life?
Due to the fact the any methane on Mars will require a source continually replenishing it, biological activity is an exciting proposition – but, it’s one we probably won’t be able to confirm with Curiosity regardless. Any life that could be contributing to the methane issue on Mars is likely well below the surface and out of range of the rover – and also, who the hell knows where to look? So just take a breath. If it is life – odds are we won’t find out for a long time.
But it could be from something else!
How about volcanoes? Sure, maybe. Mars has been, in the past, a very volcanic planet – most of its rocks are igneous (is that right?) and it boasts the TALLEST volcano in the solar system… seriously, Olympus Mons is 22 KILOMETRES HIGH. Friggen huge.
Volcanoes give off methane as they erupt – so it makes sense to blame it on the Mons… but the trouble with that is that all of Mars’ volcanic activity is, I believe, in the past – and because methane breaks down so quickly any residual effects would have already dissipated by now. So probably not volcanoes.
What else can make methane? Um… how about the sun?
There was a very interesting study published in the journal Nature earlier this year (2012), researchers at the Max Planck Institute for Chemistry in Mainz and the universities in Utrecht and Edinburgh have discovered another possible geological source which doesn’t need life – namely, f–kin’ rocks and light.
Basically, the ultraviolet radiation that breaks down methane so easily due to Mars having no protective ozone layer, shows evidence of also being able to create methane by radiating rocks, which then give off tiny amounts of methane. The rocks and dust are bombarded with ultraviolet radiation and give off methane in tiny tiny amounts, and that builds up – and we see methane on Mars.
This theory is based on research conducted here on Earth using meteorites from Mars – but it’s good science, and it explains an interesting fact, which is that the Express orbiter found highest levels of methane around the equator during the Martian summer – in the place and time where ultraviolet radiation is probably highest. (see the pic above to get a sense of the where on this one.)
Now – none of this totally rules out life. If there is life on Mars and it’s way below the surface then that would also explain the methane, but it’s an unlikely and by no means definite answer to what can only be described as very small amounts of the gas. So what do we do next? Easy – WE DO A SCIENCE.
Curiosity will continue to monitor the atmosphere using SAM and we will start to get a good picture of how the seasons effect the air on Mars and what’s in it. Curiosity will also be able to tell us what KIND of methane we’re dealing with – which isotopes and such we’re looking at – which should give us strong clues as to how the methane was created.
And then, in 2016 the ExoMars Trace Gas Orbiter – a collaborative proposal between the European Space Agency (ESA) and the Russian Federal Space Agency (Roscosmos) – is set to start off on a mission to map out the gases of the Martian atmosphere and trace the movements and possible sources of things like methane in the atmosphere.
After that we’ll have a far better idea of what we’re looking for and how much of it there is. But let’s be clear. While methane IS a very strong indicator of possible life – in the absence of water, oxygen and other signs, it is unlikely that the Martian methane is due to some flipping space-cow we just haven’t seen yet.
Just remember – 95% of the methane on Earth comes from life, but that’s not the only way to get it, and Mars is a long way from having anywhere near enough methane to close the case.
So stay calm, and carry on.
Take care and trick-or-treat.