Martians discovered in Siberian permafrost

Russian microbiologists and their American colleagues recently discovered what hypothetical Martians could be like. They are not little green people, but microbes similar to Carnobacterium bacteria found on Earth. These organisms grow and multiply under conditions close to those on Mars, and were found in the Siberian permafrost.

It is no secret that life on Mars is hard due to the planet's harsh conditions. The Red Planet has a fairly thin atmosphere (its pressure is 160 times lower than that of the Earth) mostly composed of carbon dioxide (95.32 percent). This atmosphere cannot retain solar heat. In addition, there is no water in liquid form on Mars, i.e., there are no heat storage reservoirs and distributors similar to the earthly seas and oceans.

As a result, the average surface temperature of the planet is approximately -50 ° C. It ranges from -153° C degrees at the pole in winter and over +20 ° C on the equator at noon. That is, the main problem for the hypothetical Martian life would be cold, because living organisms would have to spend several times more energy to stay warm than their terrestrial counterparts.

Of course, one cannot rule out a devastating effect of cosmic radiation, because low oxygen atmosphere is not a good protector. Recently, a group of American microbiologists found that the radiation level at the surface of the Red Planet is so high that at the depth of less than ten centimeters long-term existence of organisms "made" of carbon polymers was not possible. However, it should be mentioned that they were talking of the organisms found on today's Earth. In fact, living cells are able to protect themselves from harmful radiation, if need be.

For example, they can create organic pigments or "antidotes" neutralizing harmful effects. Incidentally, according to a wide-spread theory, a long time ago photosynthesis originated on Earth as a way to cope with ultraviolet light. Only later some of the bacteria "thought of" using it for the production of organic matter. This means that the problem of radiation for Martian microorganisms is likely to be solved quickly. However, adaptation to the low temperatures of the Red Planet would be much more difficult.

Yet, "difficult" does not mean "impossible." This was recently proved in an interesting study conducted by Russian microbiologists from the Institute of Physical and Biological Issues of Soil Science and their American counterparts. The researchers suggested that once water on Mars exists only in the form of ice, they would have to look for bacteria that can withstand the difficult conditions of the Red Planet in sandy sediments that lie in the horizon of the permafrost and whose structure resembles Martian regolith.

In fact, there is a number of such deposits in Russia, on the banks of the Siberian rivers in the permafrost zone. The scientists took samples of the bacterial flora at the depth of 20 meters on the right bank of the Kolyma River. Then the scientists washed the sand samples and then placed the substance containing various microorganisms in nutrient-rich environment. Initially, the bacterial colonies were grown at 28 ° C in a normal atmosphere in order to obtain a large number of units.

Once this was achieved, the researchers proceeded to the second stage of the experiment - growing bacteria under the conditions similar to the conditions on Mars. Obviously, not all of the conditions were reproducible. Microorganisms were cultivated under the conditions of zero temperature, low oxygen, and the total pressure of seven millibars (approximately 150 times lower than that on Earth). That is, the pressure and temperature were higher than on Mars. However, not all one-celled "Siberians" were able to withstand the torture. Within 30 days, of ten thousand isolates only representatives of six species grew and multiplied.

Interestingly, all these potential "Martians" belong to the Carnobacterium genus. These creatures are normal inhabitants of the soil in the permafrost and do not occur in a warmer climate. They do not need oxygen, and live by decomposing dead organic matter under anaerobic conditions. Incidentally, during the experiment it was discovered that one of the strains of unicellular "extremists" were more comfortable under cold and low pressure conditions and nearly complete absence of oxygen. Under normal circumstances, their colonies grew poorly, but in the "Martian" environment they blossomed.

Previously, this group of bacteria was found in the lakes of Antarctica. They were known to be able to live in isolation under ice for long periods of time. Incidentally, their Siberian relatives do not mind living in isolation. The scientists suggested that the representatives extracted from the permafrost of Kolyma got there six to eight thousand years ago and have since been cut off from the outside world. Over this period they were able to adapt to the extreme environmental conditions so well that these conditions became the norm for the bacteria.

Microbiologists believe that the results obtained in the course of this experiment are very important for the proper understanding and evaluation of the possible existence of any life on Mars. Simply put, now there is an understanding of what the hypothetical Martian bacteria could be like. This means that now scientists can upload information on the structure and physiology of Carnobacterium into automatic memory research vehicles that study the surface of the Red Planet and order them to look for something similar. It is not ruled out that this would make the search far more productive.

Anton Evseyev

Pravda.Ru 

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