Astronomy

I am skeptical of the premise that long chain hydrocarbons can only be explained by life. Mostly because that logic fails whe examining how life arose on Earth in the first place. If complex organic molecules can only form life, then how did life arise on Earth to begin with? Life itself is complex organic chemistry and large organic molecules. If complex molecules like polypeptides and RNA can't form without life, then life can't come into being in the first place. Particularly with these long chain hydrocarbons it's not that hard to imagine exotic conditions where they might be able to form. It is certainly easier to imagine these conditions than imagining the self replicating RNA or polypeptide strands that most likely became life as we know it. If they had found chains of nucleic acids or amino acids I would be a lot more willing to buy that it's a sign of life. But hydrocarbons? It's definitely interesting and a very good thing to look into (particularly in terms of the origins of life) but it's far from a smoking gun.

That said, I am very interested in this finding because, at the end of the day, I do think it is relevant to biochemistry. Mostly that there are two possible explanations and both are important. If it's not proof of life on Mars (I don't think it is), then it is proof that complex organic molecules have formed elsewhere in relatively normal chemical conditions in the universe without existing organisms, which is a major unsolved problem in trying to determine the origin of life.