The surface of Mars and its shallow depths are not suitable for living organisms to exist as liquid on a planet is formed in a fairly harsh environment and can not survive for long in a stable condition. To such conclusion scientists came on the basis of modeling behavior of the Martian “brine” in the modern world. An article telling about the results of a study came in Nature Astronomy.
Today on Mars there is liquid rivers and lakes — water it is found only in deposits of ice and a small amount of vapor in the atmosphere. This is due to the fact that the planet is very cold (average annual temperature is approximately -60 degrees Celsius) and the pressure at the surface is 160 times smaller than the earth, resulting in the water instead of melting, immediately passes into the gaseous state. However, scientists have long attempted to detect liquid water on Mars and, as it turned out, not in vain. The fact that even at temperatures significantly below 0 degrees Celsius water can exist in the liquid state due to the dissolved salts. In 2015, physicist Logendra OGA found on the planet, dark strip, which, as considered by scientists, could be seasonal flows containing salts of perchloric acid. Later it turned outthat, most likely, it is the flow of sand, but the discovery prompted astronomers to new research.
To determine how the salt water will behave on the surface of Mars, Edgar Rivera-Valentin (Dr. Edgard Rivera-Valentín) from the Lunar and planetary Institute in Houston, along with colleagues conducted a computer simulation. The researchers combined information about the weather conditions, measurement of spacecraft data and laboratory experiments with salts, which are found on the Martian surface (perchlorate, magnesium perchlorate and calcium) to understand how stable will the solutions of these salts and where they may occur. For perchlorate, magnesium the index of activity, which can be considered as a measure of salinity (1 — distilled water, 0 — pure salt) was 0.56, and calcium perchlorate — 0,52.
It turned out that the “brine” can meet 40 percent of the surface of Mars, mostly in mid-and high Northern latitudes. However, in a stable condition he would have only seasonal and only 0.04 percent of the year (6 hours for 687 earth days). In addition, its temperature will be very low — about -48 degrees Celsius, about 25 degrees below the known allowable values for life on Earth. From this, the researchers concluded that the known organisms are unlikely to exist in such an environment.
The authors do not rule outthat the Earth may exist not yet discovered forms of life that will feel comfortable in these conditions. On the other hand, their results show that the risk of biological contamination of Mars is quite low, which may be useful in future missions.
Today, many studies indicate that the ancient climate of Mars was much more favorable for the existence of organisms. So, one group of scientists concludedthat about four billion years ago, there could theoretically inhabit lithotrophy — microorganisms that use the energy of inorganic compounds. Today the search for life on Mars associated with the registration in the atmosphere of methane — a frequent companion of living organisms on Earth. In detail about it we wrote in the material “is There a cow on Mars”.