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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.
Working under a portion of a one million dollar grant from NASA, the group -- just two months ago (in Mid-June) -- found a species of cold weather, radiation-resistant microbes that's never been seen before. It's called "Hymenobacter" and is the same Genus as microbes found in Antarctica and Arctic Canada.
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.
In the wake of Viking, it seemed less likely that life could exist right now on Mars. But evidence that the planet was once warmer and wetter -- and could have harbored life billions of years ago -- has been accumulating.
One reason scientists now believe that Mars may have harbored life in its distant past is because of all the Carbon Dioxide Ice that is today locked-up at the planet's North and South Poles.
The quantities of CO2 ice are enoromous. In fact, if you sublimated it all, you would end-up with a relatively dense planetary atmosphere -- an atmosphere that would also be warm. The well-documented "greenhouse Effect" of Carbon dioxide would heat Mars up to the point that its average temperature would be about the same as Alaska's. And Alaska, because it has seasonal flowing water, is full of microbes and plant life (not to mention animal life).
Calculations have been done showing that every once in a great while, Mars flips over wildly on its poles. This flipping takes place over a period of tens of millions of years. That's because unlike Earth, Mars does not have a relatively large moon spinning around it. The Earth's Moon -- due to gravitational tugging on the Earth's equatorial bulge -- does not allow our planet to "topple over". It keeps Earth's axis very close to a 23.5 degree inclination with respect to the sun.
But Mars, without a big moon, is free to topple over as much as 60 degrees on its axis -- like a spinning top running out of energy. When that happens, it's hypothesized, the carbon dioxide in the pole facing the sun sublimates, creating a dense, warm atmosphere.
Under such conditions, the permafrost -- believed to exist beneath much of the Martian regolith (or soil) -- would melt, creating flowing water.
On earth, wherever there is liquid water, there is life.
These theories have shaped "Curiosity" into the rover that is only capable of searching extant life. And for that, the vehicle and its mission were beautifully designed.
8 months ago -- when it launched from Florida on its 350 million mile journey -- Curiosity was aimed at a specific section at the edge of a specific crater on Mars. And after that 350 million mile journey the vehicle landed almost precisely in the middle of its touchdown ellipse.
NASA said the trajectory was so precise it was like firing a pea-shooter from Florida and hitting a dime in downtown Los Angeles. Not just ANY dime, the specific dime that you were aiming for!
Such accuracy is important because the "dime" that NASA was aiming at is Gale Crater. It's a crater has evidence of ancient flowing water. It also has evidence of clay-like soil, which is believed to have formed in the presence of ancient seas.
Curiosity is equipped to examine these promising mineral formations, and even test them for signs of organic compounds -- the compounds that make up all life on Earth.
The work that the U.A.A Students are doing is not likely to directly affect the interpretation of data fed to Earth by Curiosity. But it may be helpful for future Mars Missions -- which are designed to search more directly for life.
Cold, desiccated environments -- like the dry valleys of Antarctica, and certain parts of Alaska -- seem to contain microorganisms which have evolutionary adaptations that are very likely to be useful on Mars.
By studying these cold places on our planet, we may -- in the future -- be equipped to recognize evidence of life, or extant life on Mars.
Without studying such "Mars Analogues" on Earth, we risk sending billion-dollar-spacecraft to the Red Planet, and not recognizing what could be the most significant finding in the history of biology: the existence of microbial life beyond Earth.
Is there life on other worlds?
It's a question humanity has asked for much of the 200,000 years that modern man has roamed the earth.
You and I are lucky enough to be part of the first generation of human beings who can ask that question, and reasonably expect to receive an answer.