Does methane mean life on Mars?

Space boffin Richard Hollingham gave Chris Smith his thoughts...

Richard - It's one of those classic examples where scientists can hold their hands up and say, we don't know. The first hints of methane were actually found by the European space agency's Mars express spacecraft quite a few years ago now. And now the curiosity Rover, the NASA Curiosity Rover, which is obviously trundling along the ground on Mars has also detected methane. But the trace gas orbiter, so another spacecraft in orbit around Mars, has not detected this methane in the same places. So it could be that there's a fault with Curiosity with the sensor, or there might be methane, but it's not quite making it to the 3 or so kilometres where the trace gas orbiter can detect it. So the might be methane there might not is the answer to the question. And the reason of course everyone's excited about methane is it could be an indicator of life, it could mean that actually, something is producing methane the way that we do, cows do. And the other weird thing is that methane should, according to the way that Mars atmosphere works, it should last for about 300 years on Mars. So again, there's a mystery as to why the trace gas orbiter in orbit around Mars is not detecting methane if the planet is constantly producing it.

Chris - This would therefore be what - some pockets of microbes that have the metabolic machinery to turn organic carbon rich stuff into methane and that would indicate that they are there doing that. That's why this matters?

Richard - That's why it matters but it could be some sort of geological process as well, so we really don't know

Chris - So how will they investigate? How will they find out what this is?

Richard - Well it's like all these things, the more experiments you can throw at it the better. I mean, we've got new experiments going to Mars, new rovers going to Mars all the time. At the moment what's at Mars has not got the capabilities to prove one way or the other, but we're just getting these tantalising glimpses continuously. And this has been over the last 10 years that there is methane there. As to where it's coming from, we probably won't start knowing the answers to this until we can either go to Mars ourselves or bring samples back from Mars in one of these likely areas. Maybe that'll give hints that there is some sort of, or had been some sort of, life there

Chris - Exciting times, isn't it. We watch with interest to see what happens.