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ANCHORAGE, Alaska—
This week, as a $2.5 billion rover touched down on the surface of Mars, U.A.A students were watching intently. And they weren't watching out of mere "curiosity" either (pun intended). They were watching because their research may play a pivotal role in answering the question that the Curiosity Rover is trying to answer: was there once microbial life on Mars.
Allison Zimont, a Biological Engineering student of Dr. Fred Rainey at U.A.A, was with a group of students on a field expedition to the Matanuska glacier. It just so happens that a sample of snow and ice that she collected contained a dormant microorganism that had been "asleep" under the cold conditions that existed on the glacier.
When researchers warmed the organism, and put it in nutrient rich petri dishes, it thrived. When they bombarded it with Gamma and Ultraviolet radiation, it proved hard to kill. In fact, they hit it with doses of Gamma Rays that would destroy many other organisms, including animals. They found that "Hymenobacter was able to repair its own DNA.
This is precisely the kind of evolutionary adaptation that could prove useful in an organism trying to survive on Mars. And NASA believes that if there is life on Mars, it should have the kind of cold and radiation resistance that is key to survival in places like Antarctica and much of Alaska.
The question of current life on Mars is highly controversial. The planet has offered tantalizing clues that it might be something other than a completely dead world, but no outright proof. For example, Mars emits methane gas, an unstable molecule that's prone to catch fire here on earth. A big source of methane on our planet is living microorganisms and even full-sized animals like cattle. No one knows whether the source of the mysterious methane is biogenic (from life) or abiogenic (of non-living origins). All we know is that it's there, and out-gassing from the Martian Soil.
To further complicate the issue of life on Mars, consider the tale of the Viking Landers.
36-years ago those two American Spacecraft -- credited with the first successful landing on Mars -- found no evidence of life.
Or did they?
The fact is that while two biological experiments aboard Viking seemed to rule out microbial life, a third experiment -- called "The Labelled Release" gave highly ambiguous results.
At first NASA actually suspected that the Labelled Release might have actually made a significant biological finding. It found a big out-gassing in Martian Soil deposited in its test chamber. It was an out-gassing consistent with the presence of microorganisms eating and metabolizing radioactively labelled nutrients fed to them.
But later analysis attributed spikes in gasses in the to non-organic sources, such as so-called "Super-Oxides" in the Martian Soil.
But -- to this day -- no one really knows what the results of the Labelled Release Experiment really mean. That's because since 1976, the experiment has never been duplicated on the surface of Mars.
Of the five spacecraft that have landed on Mars since Viking -- none has carried a life-seeking laboratory.
Part of the reason is complexity expense. After all, how do you build a portable biological laboratory designed to find microorganisms which -- by definition -- are unlike any microorganisms you ever seen before?
Another reason no biological lab has again been flown to Mars is frustration with the ambiguous Viking results. After all, why send a Rover on a biological mission to the Red Planet if all you're going to do is argue over the results for 36 years?
Some scientists think that a Mars "Sample Return" mission is the only proper way to scrutinize a Mars rocks for signs of life.
That's why Curiosity was designed to be the Rover it is: a Rover with no biology lab. It simply cannot search for life directly.
