Jul 22, 2011 15:02 GMT  ·  By

Undoubtedly, the day when the NASA Viking 1 spacecraft landed on the surface of Mars remains one of our species' most glorious moments. But this flight is also one that may have put us back by a few decades in terms of understanding the origins of life.

The main goal the lander had was to figure out whether Martian life existed. The spacecraft was outfitted with a variety of scientific tools to aid with its investigations, and all of them were heavily used for digging and subsequent studies.

Viking landed on Mars on July 20, 1976, marking the beginning of a new age in space exploration. Finding organic life on our neighboring planet would have most likely changed our lives for ever, but socially, religiously, politically, and philosophically.

This is why when news that life was indeed found on Mars broke loose, people were baffled. The probe's detectors had picked up signs of organic molecules such as dichloromethane and methyl chloride, as well as indications that water was also present on the desert planet.

But the findings were rapidly made the target of controversy, and researchers ultimately established that the organic molecules the spacecraft had found were in fact traces of chemical contaminants taken to the Red Planet from Earth.

The issue of planetary cross-contamination is a very real one, experts at NASA say. They take precautions not only to sterilize spacecraft when they return from other cosmic objects, but also when they are dispatched.

If we want to search for life on Mars, then we destroy our own efforts if we seed life there when there was none. At this point, it's still unclear whether the Red Planet was contaminated or hot. If so, teasing native lifeforms (if any) from the ones originating on Earth will be very difficult.

Even today, the international scientific community is debating Viking's findings. There are innumerable arguments to support the views of both sides, and its highly improbable that the conflict will be resolved any time soon, Space reports.

“One school of thought, exemplified by Gil Levin, made the cause for life, while the other from Norm Horowitz argued against it on Mars. The Viking experiments remain inconclusive,” Mars Society founder and president Robert Zubrin explains.

“The real question of Mars is about life, and to answer it we'll need people there. If one thinks the laws of science of life on Earth are the same elsewhere in the Universe – which I do – then it's rational to believe that life once developed on Mars when it was a warm and wet planet,” he adds.

“There may now be fossils on the surface and maybe living organisms underground,” Zubrin concludes.