The bacterium hates oxygen and produces methane, and it grows and reproduces in an environment that is a simulation of that of Mars, which is unable to support most living things on Earth
Terrestrial bacteria were able to grow in conditions similar to those on Mars. An experiment raises the possibility of life on Mars - of methane-emitting bacteria
4.9.2002
By: Avi Blizovsky
Some of the strangest bacteria on Earth can grow in an atmosphere and soil conditions reminiscent of those on Mars, raising the possibility that life may have survived on the Red Planet. This is what scientists claim.
These creatures, called methanogens, survived in a thin atmosphere of hydrogen and carbon dioxide and in extreme areas of volcanic ash designed to mimic the conditions of the Martian soil, including density, grain size and magnetic properties.
The result of the experiment, in addition to the presence of hidden underground water on Mars, helps support the theory that the red planet was once home to life, says Tim Krall, a researcher at the University of Arkansas in Fayetteville.
"This experiment confirms the results of the successful missions to Mars in the last decade - Pathfinder, Global Surveyor and Odyssey, and especially the discovery that there may be a huge ocean that has survived below the surface to this day." Krall said.
Krall and his colleagues grew the bacteria in an experiment in a pressure chamber where the atmospheric pressure was half that of Earth. They measured the increase in the number of bacteria by measuring the methane they produced.
"If life exists below the surface of Mars, it would need alternative energy for photosynthesis, the process that plants use to make fuel from sunlight."
The methanogens, which survive in one of the most hostile environments on Earth - in volcanoes and in areas of volcanic eruptions on the seabed, get the energy they need not from the sun but from the oxidation of inorganic substances, in their case hydrogen and carbon dioxide. Assuming that hydrogen and some water exist below the surface, the basic requirements for the growth and reproduction of the methanogen bacterium are met on Mars. said the scientists who conducted the experiment in a press release.
Even if there is no life on Mars, Kral estimates that if the player survives further experiments they conducted under extremely difficult conditions, they will be able to reach Mars in the future by humans so that they release the methane gas, which is a greenhouse gas, and thus they will raise the average temperature there above the freezing point in favor of The human settlers.
However, such "landing" may take hundreds or thousands of years before it can help the survival of more conventional earthly forms of life. In any case, there are many ethical and environmental questions that need to be resolved, says Kral.
However, Chris McKay of NASA's Ames Research Center in Moft Field, California, reminds Krall and the readers that the atmospheric pressure on Mars is not half that of Earth but a fraction of it, and therefore one of the important data in the experiment was wrong, however, he said, this is an important step in the right direction, and in particular The organism they chose is interesting, since if subterranean life exists on Mars, our best guess was that it would be methanogens." said.
Previous news on the subject
2/6/1999
A rare type of terrestrial bacterium has been able to live in laboratory conditions that mimic the environmental conditions of Mars, raising new hopes that Mars may be a source of life for primitive forms today or at least did so in the past, researchers say.
Timothy Krall from the University of Arkansas, says that the bacterium hates oxygen and produces methane, and it grows and reproduces in an environment that is a simulation of that of Mars, which is unable to support most living things on Earth.
Krall, who reported the results of his research at a meeting of the American Society for Microbiology, said he and his colleague Curtis Beckum (Bekkum) created this environment in culture plates. The plates did not contain any oxygen, but they were immersed in carbon dioxide and hydrogen gases. The soil used in the experiment represented everything known about the Martian dust, and it has no organic nutrients and only traces of water.
"We started from the assumption that there is liquid water under the surface" said Krall. Many planetary experts believe that Mars once contained large amounts of water, and that traces can still be found below the surface. In this mixture, the researchers introduced a group of bacteria called methanogens, a type of bacteria that live in places where there is no oxygen, such as in the depths of the earth or around chimneys on the sea floor. Some types of methanogens even live in the intestines of cows, where they help digest the grass.
All these types of bacteria, he says, use nitrogen and hydrogen to produce methane, a natural gas that can also be used as fuel. To find out whether the bacteria would survive in the simulated environment, Krall said he measured the amount of methane produced inside the sealed culture plates. "They will produce methane as they produce on Earth", he says, "they grow beautifully in the conditions of Mars".
Although the experiment is far from providing a final answer, Krall says that the fact that the bacteria thrived "increases our belief that life on Mars is possible, or at least was possible in the past." Kral says that the experiment also raises the possibility that bacteria can be used to change the climate on the surface of Mars, among other things to adapt to human life in the future. "If humans want to reach Mars one day and bring life to its surface, this could be the form of life they would want to grow there," he says. "If you want to try to create conditions similar to those on Earth, seeding this organism on Mars would be the initial step."
Kral says that the colonies of the methanogens will emit methane gas that can help change the climate and temperatures on Mars. The surface of the planet is very cold, but if methane gas is released into the air it can create the greenhouse effect. Methane is a known greenhouse gas, which means it will help warm the planet. "The greenhouse gases allow the sun's rays to heat the planet's surface, but prevent the sun's heat from escaping back into space." Methane may also provide the energy for a human colony on Mars," says Krall. The gas can be used as fuel and it can even be processed into rocket fuel.
NASA has explored the idea of launching an automated spacecraft that would produce methane on Mars. Kral says, using hydrogen imported from Earth, and carbon dioxide from the Martian atmosphere, it will be able to produce and store the methane. According to him, the fuel will enable sending humans to Mars. They could use the methane to launch themselves back to Earth, he concludes.
Methanogenic bacteria could, in theory, be used on Mars to produce methane and to provide the energy needed for human settlement on Mars, Krall says.
