Bacteria Can Grow in Simulated Mars
By Paul Recer
AP Science Writer
CHICAGO (AP) _ A methane-making, oxygen-hating microbe is able to thrive in Mars-like laboratory conditions, according to a researcher who says the experiment raises fresh hope about the possibility of life on the red planet. The microbe, said Timothy A. Kral of the University of Arkansas, ``grows just fine and dandy'' in a simulated Martian environment that would kill most every other forms of Earth life. Kral, who is reporting on his research Wednesday at the national meeting of the American Society for Microbiology, said he and a colleague, Curtis Bekkum, created an environment in culture dishes that closely mimics the environment of Mars. The dishes contained no oxygen, but were bathed in carbon dioxide and hydrogen gases. The soil in the experiment resembles what is known about Martian dirt, with no organic nutrients and tomach of cows where they help digest grass. All of these types of microbes, he said, use nitrogen and hydrogen to make methane, a natural gas that can be used as fuel. To determine if the bacteria lived in the simulated Martian environment, Kral said he measured the amount of methane produced inside the sealed culture dishes. ``It made methane just like it does on Earth,'' he said. ``It grows just fine in the Martian conditions. In fact, it grew fine and dandy.'' Although the experiment is far from the final answer, Kral said the fact that the microbes thrived ``cautiously increases our belief that life on Mars is possible, or at least it was possible.'' Kral said the experiment also raises the possibility that the microbes could be used to cause a change in the planetary climate of Mars. ``If man were to go to Mars someday and introduce life, this might be the form of life that would grow there,'' he said. ``If you were going to try to create an Earthlike conditions there, putting this type of organism on Mars might be the thing to start it.'' Kral said that colonies of methanogens would give off methane gas that could help change the climate and temperature of Mars. The planet surface now is very cold; but if methane collected in the atmosphere, it eventually could create a greenhouse effect, he said. ``Methane is a greenhouse gas, which means you could warm up the planet,'' he said. Greenhouse gases allow the sunlight to hit the planet surface, but prevent the solar heat from escaping back into space. Methane also could provide the energy for a human colony on Mars, said Kral. The gas can be used as fuel and could even be processed into a rocket propellant. NASA has been studying the idea of one day sending a methane-producing robot spacecraft to Mars, said Kral. Using hydrogen brought from Earth and carbon dioxide from the Martian atmosphere, it would be possible to make and store methane, he said. The fuel then would be available when people are eventually sent to Mars. ``They could use the methane to rocket themselves back to Earth,'' he said. Methanogen microbes, in theory, also could be used on Mars to make methane and provide the energy needed for a human colony there, said Kral.