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21 January 2011

Viking DID find Organic Compounds

Science is cool.  But sometimes we do something wrong, or look at it the wrong way, and mess things up.  What is cool about it is that science is repeatable, and you can perform more experiments as you learn more things, or get new tools.  That's why it may seem like science is constantly changing, because it is!  But the reason it changes is that it's getting better.  So I am puzzled by some people's resistance to those changes (maybe they prefer leeches and barbers to real hospitals and things like that?).

So this is one of those instances where we really didn't know what we found based on the fact that we didn't know what the surface of Mars was like.  Subsequent missions, rovers, landers, and observations have given us more data, and now we can do some tests to better understand what was really happening.  Read the article carefully though.  Organics are totally different than life.

Viking Found Organics on Mars, Experiment Confirms

Viking 1 LanderMore than 30 years after NASA's Viking landers found no evidence for organic materials on Mars, scientists say a new experiment on Mars-like soil shows Viking did, in fact, hit pay dirt.

The new study was prompted by the August 2008 discovery of powerful oxygen-busting compounds known as perchlorates at the landing site of another Mars probe called Phoenix.

SEE ALSO: To Mars! Zambia's Forgotten Space Program

Scientists repeated a key Viking experiment using perchlorate-enhanced soil from Chile's Atacama Desert, which is considered one of the driest and most Mars-like places on Earth, and found telltale fingerprints of combusted organics -- the same chemicals Viking scientists dismissed as contaminants from Earth.

"Contrary to 30 years of perceived wisdom, Viking did detect organic materials on Mars," planetary scientist Christopher McKay, with NASA's Ames Research Center in California, told Discovery News. "It's like a 30-year-old cold case suddenly solved with new facts."

"If the Viking team had said 'Well, maybe there's perchlorate in the soil,' everybody would have said they're crazy -- why would there be perchlorates in the soil? It was only by having it pushed on us by Phoenix where we had no alternative but to conclude that there was perchlorate in the soil … Once you realize it's there, then everything makes sense," McKay added.

SLIDE SHOW: Remember one of the most successful Mars missions by browsing Phoenix's first photos just after it landed in the Martian arctic.

The Viking team's verdict that Mars lacked organics was the lynchpin argument against another Viking experiment that looked for signs of microbial life. In the experiment, a bit of nutrient-laced water was added to a sample of Martian soil.

The air above the soil was then monitored for signs that the nutrients had been metabolized. The instrument detected tracer gases the first time the experiment was done, but subsequent runs did not. The results were considered inconclusive and remain contested.

New evidence for organics on Mars does not mean Viking found life, cautions McKay.

SEE ALSO: Travel to Mars in 3 Hours

"Finding organics is not evidence of life or evidence of past life. It's just evidence for organics," he said.

But if NASA had realized there were organics on Mars, there might not have been a 20-year hiatus in sending landers for follow-up studies, said Rafael Navarro-González, with the Institute of Nuclear Science at the National Autonomous University in Mexico.

"We might have had continuing missions," Navarro-González told Discovery News.

NASA plans to launch a follow-up mission to look for organics on Mars in November.

SEE ALSO: A Blue Sunset On Mars

The research appears in last month's Journal of Geophysical Research.
I also recommend you go to the page itself. It has tons of links to other cool stories about Mars and science. Well worth a visit.

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