News Mars may not be lifeless, say scientists

[garyw]

Source: http://www.bbc.co.uk/news/science-environment-11201699

When Nasa's two Viking landers picked up and examined samples of Martian soil in 1976, scientists found no evidence for carbon-rich molecules or biology.
But after the Phoenix Mars Lander discovered the chlorine-containing chemical perchlorate in the planet's "arctic" region in 2008, scientists decided to re-visit the issue.


They travelled to the Atacama Desert in Chile, where conditions are believed to be similar to those on Mars.


After mixing the soil with perchlorate and heating it, they found that the gases produced were carbon dioxide and traces of chloromethane and dichloromethane - just like the gases released by the chemical reactions after the Viking landers heated the Martian soil more than three decades ago.

Whilst this is all fine and great and I certainly think something odd was going on with those Viking samples I do think that comparing the Atacama desert to Mars is missing the point, after all, Mars surface conditions are much colder, much lower pressure, less water and no oxygen.

Now, if they had lifted some of the soil from the Atacama desert and placed it into a facility that let them truly simulate conditions on Mars I think we would have a better idea of the feasibility of life on Mars.

 

[N_Molson]

Mars is a whole planet to explore... We need a lot more return-samples missions, with a greater variety of geological samples. Also it would be good to make a real drill and collect samples let's say 10 meters under the surface, to get into something else that the superficial sediment layer.

Drilling and in-situ analysis would be a perfect scientific task for a program of manned missions, on different sites like Apollo did.

 

[T.Neo]

Yeah... I think the serious chances of life on Mars are underground, not on the surface in the topsoil.

I've been wondering about simulations putting Earth life through Martian conditions. Life from the Atacama or McMurdo valley would probably be a good bet for test subjects.

 

[RisingFury]

Whilst this is all fine and great and I certainly think something odd was going on with those Viking samples I do think that comparing the Atacama desert to Mars is missing the point, after all, Mars surface conditions are much colder, much lower pressure, less water and no oxygen.

You can't assume that any Martian life would require the same conditions that can be found on Earth. You're saying: Earth life can't survive on Mars therefore no life is possible on Mars.

 

[T.Neo]

While it is important to remember that there is no reason for alien life to be like life on Earth, there is also no reason for alien life to be strange and alien "for the sake of it".

And life on Earth gives a good starting point for life on Mars, especially considering that the two might share a common ancestor in the distant past.

 

[garyw]

You can't assume that any Martian life would require the same conditions that can be found on Earth. You're saying: Earth life can't survive on Mars therefore no life is possible on Mars.

I know what you mean but by the same token you can't use the Atacama Desert as an analogue of Mars.

 

[Orbinaut Pete]

Here's the original JPL press release:

JPL: "Missing Piece Inspires New Look at Mars Puzzle".