Venus is a good illustration of hell, and the illustration is quite real. 470 ° C on the surface, pressure of 90 bar, acid fumes – there can be no question of the existence of life on or under the surface, even deep, microscopic, and out of the question. But the conditions are completely different – in the upper cloud layer, at an altitude of 50 to 65 km.
Everything is relatively good here. According to a number of scientists, if you look for life on the Earth’s neighbor, it is in the clouds. True, not the entire scientific community agrees with this opinion either. Let’s see what versions of cloud life are on Venus.
Clouds on Venus and conditions
The planet’s troposphere begins at the surface and ends at an altitude of 65 km. Below, as far as we know, the winds are relatively weak, but in the upper part of the troposphere, the temperature and pressure decrease to Earth values, so that the wind speed increases to tens of meters per second.
As for the pressure, at the very surface of the planet it is more than 90 times higher than that of the Earth, but just in the upper part it reaches values characteristic of the near-surface layers of the Earth. The height of the clouds on the night and day sides of the planet is different. In the first case, it is about 90 km, in the second – 65 km.
According to scientists, the tropopause is closest to terrestrial conditions. This is the border between the troposphere and the mesosphere, which is located above 50 km. Measurements were carried out here by Soviet and American probes, as a result of which it was possible to find out the temperature and pressure. As for the temperature, it reaches 20 – 37 ° C, with a pressure of about 1 bar. The troposphere contains carbon dioxide and water vapor, albeit in small amounts.
Clouds and clouds, why so much attention?
The fact is that scientists have been observing them for several decades, and the instruments and methods of observation are constantly being improved. Among the tools are specialized equipment for three spacecraft at once:
- UV scanners “Venera-Express”, devices of the European Space Agency.
- UV scanners “Akatsuki”, the Japanese interplanetary station.
- Spectrometers “Messenger”, the American interplanetary station.
- Hubble Space Telescope Capabilities.
Thanks to all this, it was possible to find out that the albedo of clouds, consisting mainly of sulfur dioxide and sulfuric acid, reaches 75%. But there are also areas with much lower albedo – up to 50% and below. The spots are not constantly in one place, but change both location and configuration. There are several explanations for this phenomenon, but the most attractive for us is biogenic. Scientists believe that these spots are clusters of certain particles that absorb radiation in a wide range, from UV to visible light. Of course, the nature of the particles can be different, including just biogenic.
There are grounds for this assumption – the fact is that the spectrum of absorbed radiation and the particle size are approximately the same as that of microorganisms in the atmosphere of our planet. Among the admirers of the biogenic hypothesis of the origin of the Venusian “spots” is Carl Sagan.
Another argument in favor of biogenicity is the detection of Venus in the atmosphere glycine and phosphine… Glycine is very important for the prebiological “evolution” of organic matter and is one of the factors in the emergence of life. As for phosphine, this compound is one of the signs of the existence of life – on Earth it is produced by anaerobic organisms.