So, media excitement leading to Curiosity's landing is picking up and this article serves as well as any other, as an overview summary of the history of the hunt for organics on Mars: Curiosity's search for organics.
Trying to not anticipate too much from Curiosity, is not all together easy, particularly because of the controversy and debate stemming from Viking's findings, and the subsequential McKay speculation based on soil Perchlorates destroying any hypothesised organics during the heating process. Team leader for Viking's GC-MS instrument, Klaus Biemann's refutation of McKay's ideas, also help to bring things back to a balanced outlook. Hopefully, at the very least, Curiosity's findings may progress thinking incrementally …
The following quote provides some background:
The main instrument package on Curiosity for detection of organics is the Sample Analysis on Mars (SAM) package.Klaus Biemann, leader for the Viking GC-MS experiment, has sharply criticized the perchlorate theory. In a published comment on the Navarro-Gonzalez and McKay paper, he and Jeffrey Bada of the Scripps Institution wrote that the theory is based on faulty data and unfounded extrapolations, and that it ignores the known presence of several cleaning compounds found in the GC-MS during the Viking experiments. They also contend that if the process described by McKay and Navarro-Gonzalez had taken place, that other compounds – in this case other chlorinated aromatic molecules – would also be produced on Mars, yet they were not.
The two agree that meteorites with organic carbon do indeed fall continuously onto Mars, as they do throughout the galaxy. But they argue that the organics are destroyed by high-energy radiation, which in turn leads to a build-up of equally destructive oxidizing agents. Biemann says that the GC-MS instrument used by Curiosity is, in some ways, an advance over the ones on the Viking landers. That’s why, he said, if Curiosity is not able to detect organics, then it becomes ever more apparent that those compounds can’t survive on the Martian surface. “It’s end of story,” he said.
The Principle investigator for SAM, Paul Mahaffy, has some interesting questions:
I'm not quite sure how much could be learned from a non-organics finding although, I do think it would be a quite a surprise for some.Originally Posted by Mahaffy
Its also interesting that the approach seems to be more along the lines of developing an explanation for why organics may not be present … I guess the overall non-life interpretation coming from the Viking findings, has resulted in this approach for Curiosity.
Anyway, let's hope Curiosity makes it alive in one piece and retrieves some solid, reliable data to move things along, one way or the other.
Feel free to use this thread to capture comments on the search for Mars organics as it progresses ..