Carbon on Mars

Mars, the Red Planet
wikimedia

In the previous post I introduced Robert Hurt's article on the study of PAHs in the Spitzer Space Center.

There I asked myself a simple question - is there carbon on Mars. After all, galactic clouds of space dust have PAHs and they contain carbon-hydrogen molecules. Carbon is the fundamental chemical element in all Organic Chemistry.

Well, I asked the question from wikipedia where an anonymous article tells us about the atmosphere of Mars

The atmosphere of Mars is relatively thin and is composed mostly of carbon dioxide (95.32%). There has been interest in studying its composition since the detection of trace amounts of methane, which may indicate the presence of life on Mars, but may also be produced by a geochemical process, volcanic or hydrothermal activity.
wikipedia 

So, if already Mars atmosphere has carbon, the matter called organic by chemists, surely also it is present in the elements that constitute the planetary body of the intriguing rocky planet in our neighbourhood.

But carbon is not taken as proof of life - scientists are more interested in the quest of life on the traces of methane present in the atmosphere of Mars. Where does it come from?