Another failure to discover life on Mars?

    A team of Greek and British scientists talked about a new find in the Martian meteorite: an ovoid structure, which is very similar to a fossilized microorganism.

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    Over the past two centuries of exploration of Mars, life has been "found" there more than once. At first, these were the well-known "canals", and scientists quite seriously discussed the seasonal cycles of vegetation along their shores. Later, the space age killed hopes of discovering complex life. In the 1970s, Mars conducted the first and last astrobiological experiments on NASA Viking landers. The initial experimental results yielded encouraging results - the nutrient broth began to boil, which could be considered confirmation of the activity of microorganisms, but then they reviewed the results and came to the conclusion that the chemically active soil was to blame.

    The next statement about the found Martian life did not come from anywhere - but from the threshold of the White House: in 1996, then US President Bill Clinton talked about a find that could be a sensation: in the Martian meteorite ALH 84001 they found something very similar to fossilized bacteria .

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    True, the discovery immediately cast doubt on both American scientists and Russian. Found "microbes" were too small even for microbes, but similar to the natural formations characteristic of volcanic rocks.

    Managed to contribute to the hype around Martian life and the Curiosity rover. It is not equipped with life search instruments, but it can detect hydrocarbons, i.e. organic compounds. In his first detailed geological survey in 2012, hefound a high content of chloromethanes. However, after analyzing the results, scientists found that the organics were found on the earth - from a cracked ampoule with a solvent, which was supposed to act on Martian soil.

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    The current news came from Europe, and again thanks to a meteorite. Only this is another stone from Mars called "Nakhla" . In 2006, it was already examined under an electron microscope and recognized that there were some hints of signs of petrified life in it. But flimsy.

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    After such a verdict, the study of the meteorite did not stop, it was cut into thin plates and they were already being studied. On one of the plates they found a certain oval structure, which in principle is very similar to a petrified microbe.

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    The "microbe" was examined by almost all available methods, the chemical composition of each fragment was determined, and a detailed history of the meteorite itself and the egg-shaped find was compiled.

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    According to the data obtained, volcanic Martian soil survived about 913 million years ago, one meteorite strike, which led to the instantaneous incandescence and sintering of the rock. The second blow occurred 620 million years ago, it melted permafrost and water saturated the future meteorite. Around this time, the discovered “egg” appeared in the stone. After that, the stone lay at the bottom of the meteorite crater for more than half a billion years, drying up and cracking. Finally, another 11 million years ago, another asteroid flew in, which hit the surface with such force that the stone not only flew outside the atmosphere of Mars, but also escaped from its gravitational field, setting off on a journey through the solar system. In 1911, the Martian messenger met the Earth and fell in a meteor shower in the Egyptian Nakhla region.

    The meteorite was picked up almost immediately, so he did not have time to gain earthly living creatures. However, the researchers note that they identified a lot of factors that allow us to confidently say that the found "egg" definitely flew "on board" the meteorite.

    When examining the "microbe", scientists were primarily attracted by its shape - it is noted that such regular structures had never been encountered before. For example, a "shell" consists of five layers (L1-L5 in the photo), and two clots are found inside, which are also part of the "egg".

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    The minerals that fill the "egg" are clay in nature, and are very different from the basalt glass in which they are ground. Moreover, one of these minerals is greigite .) on Earth has a unique biological origin. A study of the place of contact between the oval and volcanic glass suggests that the Martian microbe not only stuck in the crack, but also managed to bite with pieces of this glass itself.

    Another intriguing detail is where the “shell” is open (b). The correct symmetry of the rounded joints is surprising.

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    I think if this fossil were found in terrestrial rocks, then no one would even doubt its biological origin. But there is Mars, so scientists have developed three scenarios in which a similar structure could have formed without the participation of life, but with the participation of water.

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    As a result, the researchers conclude: "Based on the available data, we have to admit that the formation of the ovoid structure took place without the participation of life."

    In my unprofessional opinion: before us is one of the most convincing, to date, evidence of the existence of life in the past of Mars. But Occam’s razor is merciless to such views: if you can explain the origin without the participation of life, then you could do without it. Although I would still consult with microbiologists, maybe they recognize something familiar in this find?

    Now, if they find another such "egg" in the same meteorite or in another Martian, then we can talk more confidently about alien life. In the meantime, it remains to hope for future Martian missions that can study Mars remotely or bring a handful of stones. But in Russia, the Mars-Grunt project was postponed for the 2030s, while in the USA the Mars Sample Return program is not considered at all - all the money spent on the MSL-2020 rover. Therefore, all hope is for British scientists with microscopes.

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