Controversial claim that NASA Viking brought Martian soil contained life

Martian soil analyzed 30 years ago by NASAs Viking landers might contain life, according to a new controversial study.

Washington, Aug 24 : Martian soil analyzed 30 years ago by NASA's Viking landers might contain life, according to a new controversial study.

Joop Houtkooper of the University of Giessen, Germany, has said that the dry, freezing Martian surface could be home to microbes, whose cells are filled with a mixture of hydrogen peroxide and water.

Houtkooper re-analyzed data from the Gas Exchange (GEx) experiment carried out by the robotic landers in the 1970s and said that the Martian soil contained detectable amounts of life.

The GEx experiment detected rises in oxygen and carbon dioxide gas in soil samples collected on the Martian surface.

"If we assume these gases were produced during the breakdown of organic material together with hydrogen peroxide solution, we can calculate the masses needed to produce the volume of gas measured," said Houtkooper.

"It comes out to a little more than one part per thousand by weight, comparable to what is found in some permafrost in Antarctica," he said.

Houtkooper and his colleague Dirk Schulze-Makuch from Washington State University speculate that an organism based on hydrogen peroxide and water could survive the harsh Martian climate, in which temperatures rarely rise above freezing and can reach -238 degrees Fahrenheit (-150 degrees Celsius) at the poles.

The hydrogen peroxide would act like antifreeze for the cell, preventing its insides from crystallizing due to the cold, said Houtkooper.

He said, as hydrogen peroxide-water solutions also tend to attract water, so the alien organisms could scavenge water molecules from the Martian atmosphere.

"There does not appear to be any basic reason why hydrogen peroxide could not be used by living systems. While organisms on Earth have found it advantageous to include salt in their intracellular fluids, hydrogen peroxide may have been more suitable for organisms adapting to the cold, dry environment of Mars," said Houtkooper.

However, other scientists are skeptical of his results.

"It sounds bogus to me. I don't consider the chemical results to be particularly credible in light of the hash conditions that Mars offers," said Norman Pace, a microbiologist at the University of Colorado.

"Hydrogen peroxide inside cells is deadly in terrestrial kinds of cells. In fact, that's one way that our cells combat bacteria, by producing hydrogen peroxide locally," he said.

Houtkooper presented the findings at the European Planetary Science Congress in Potsdam, Germany this week. They are detailed in a recent issue of the International Journal of Astrobiology, reports LiveScience.

ANI