When scientists talk about the possible existence of life beyond Earth, as a rule, their attention is awarded planets and satellites, on which there are at least three conditions for potential formation of living organisms, namely – heat habitable atmosphere and water <. / p> <-! place 8352995, / science / 2016/07 / 01_a_8352995.shtml, nm2015 / v2 / article / incut, incut1_link ->
The largest satellite of Saturn – Titan – is a truly unique place. His atmospheric pressure similar to Earth, the atmosphere rich in nitrogen (in the atmosphere of our planet more than 78% nitrogen). Titan – the only place in the solar system (of course, except the Earth), where it rains and mist formed
In addition, Titan has seas, lakes and rivers -. True , they contain water in place of liquid methane and ethane.
The possible existence of life on Titan has long been debated by scientists. Many researchers believe that this is not possible, as much titanium is removed from the Sun, and because of that it is too cold. Furthermore, in addition to the satellite environment is rich in nitrogen also poisonous methane and water on Titan, and not at all. That is why earlier it was considered as not very suitable place for life
However, a recent study a group of scientists headed by David Shelloueem from Cornell University reveals that life on Titan could be formed in the absence of liquid water -. article about this was published in the latest issue of the journal PNAS.
«We are accustomed to terrestrial conditions. Our scientific activity takes place at room temperature, and the “hothouse” conditions. Titanium – is a different matter, “- says one of the authors of Martin Rahm from Cornell University.
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Scientists have studied the chemical composition of Saturn’s moon, and came to the conclusion that the present on Titan prussic acid (hydrogen cyanide, or – its formula HCN) could create the right conditions for the emergence of life. For a person poisonous prussic acid. This substance is contained in tobacco smoke, coke oven gas, released during the decomposition of polyurethane. However, even in the body prussic acid can perform useful functions – for example, it produce neurons to enhance the efficiency of transmission of nerve impulses, moreover, it is released by leukocytes and promotes the destruction of harmful microorganisms
As a result of chemical reactions. occurring on Titan, hydrocyanic acid HCN molecules contribute to the formation of polymers, in particular polyimines. Polyimines able to absorb a wide range of light rays – in a way that allows the absorption of even a small amount of sunlight that penetrates through Titan’s atmosphere. Furthermore, polyimines may become the basis for the formation of amino acids and nucleic acids (bases for proteins and DNA). “Organic molecules, liquid lakes and seas (methane, not water-), as well as some reaching solar surface – all this suggests the possibility of the formation of the environment, where it can form a kind of exotic form of life” – says an author of the work, Jonathan Lanin <. / p>
«Polyimines may exist in a variety of structures and perform many functions even at low temperatures, especially in terms of Titan,” – says Martin Ram. “Polyimines may take the form of a sheet of paper, – adds Jonathan Lanin
-. They are like the bricks, can serve as a catalyst for the passage of the primary basis of chemical reactions. We also found that polyimines absorb light – where Titan’s atmosphere is more transparent. This light can serve as a source of energy for the reactions. ”
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The authors used data obtained during the mission “Cassini-Huygens”. This device, designed by NASA in cooperation with the European and Italian space agencies, was launched on October 15, 1997. Its purpose is to study Saturn, its moons and rings. January 14, 2005 “Cassini-Huygens” entered the atmosphere of Titan. Originally the mission was scheduled until 2008, but in the end was extended to 2017.
Sample results collected by the spacecraft have enabled scientists to conduct computer modeling of processes in which it was found that polyimine could indeed serve as a “starting point” in the way of the origin of life. In addition, scientists know that the “precursor” polyimine – prussic acid could play a significant role in the origin of life on our planet. The results of this work have been published in the journal Nature Chemistry in 2015.
The authors emphasize that their findings are only theoretical, and on Titan’s surface it was found no direct evidence that this Saturn ever existed lives – even in exotic, unlike the earthly form.
However, the fact that methane can still, in a sense to replace the water and contribute to the emergence of certain forms of living organisms, scientists still disagree: for example, in a recent interview with “Gazeta.ru” Igor Mitrofanov, head of the department of nuclear planetary IKI, reported : «If we do not find anything on the Moon and Mars, the next place where to look for life – in the oceans of these satellites (we are talking about Enceladus and Europe – moons of Saturn and Jupiter -. “Times”), or to search for life forms based not on the water, but, for example, liquid methane »
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