Life is in the clouds or why Venus is attracting the attention of scientists
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.
Since 2019, phosphine, hydrogen phosphide (PH3), has been used as one of the indicators of a possible sign of life on exoplanets during their study. With all this, there is a lot of phosphine on Venus – more than it can be obtained as a result of electrical discharges (lightning) or any other means. Another interesting point – phosphine was found just in the “potentially habitable” layer of clouds – we wrote about it above. The production of phosphine requires a large amount of energy, and it is most efficiently produced by living organisms of an aerobic nature.
The chemical environment of the clouds of Venus is very acidic, phosphorus cannot exist there in free form, and phosphine in such an environment is very quickly destroyed. That is, there must be a constant source of connection – and this source is very powerful.
Healthy skepticism and cons
A team of scientists led by Queen’s University Belfast approvesthat life on Venus is impossible – neither on the surface, nor above it. Scientists studied all the data on Venusian clouds for the entire time of observing them, and then tried to understand what microorganisms of the Earth can survive on Venus. The answer is simple and straightforward – none. And we are talking about survival, and not the development of large colonies, which can be seen from the Earth for one reason or another.
According to experts, the water in the upper layer of Venus is 100 times less than even the most unpretentious microorganisms require. Despite the high concentration of phosphine, which science is still finding it difficult to explain, it is impossible to believe that Venus can be “inhabited”, even if from the point of view of the presence of extremophile microorganisms.
But, of course, all this needs to be studied, tested and rechecked – for now, we humans can only make assumptions.
If you want to do something well – do it yourself
Yes, the best test is personal. A man will hardly ever fly to Venus (although there is a project to create an aeronautical colony based on huge aircraft lighter than the Venusian atmosphere, its upper layers). Therefore, people are planning to send an automatic expedition to Venus – and not one, but two at once.
The first mission is called Davinci +, the second is Veritas. Organizer – NASA. The head of the space agency said that both aim to study the features of the development of Venus. Experts want to understand how and why the planet has evolved along its current path, reaching a stage where puddles of molten lead may well exist on the surface, and sulfuric acid rains in the atmosphere.
DAVINCI + (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging). Within its framework, NASA is sending a device to Venus that will study the atmosphere of the “morning star”. Scientific instruments on board the station will measure the concentration of various gases and other chemical elements and their compounds.
The device will first study the upper atmosphere, and then begin to search for traces of recent volcanic activity near the surface. The module will descend to the surface for about an hour, studying everything that surrounds it as it descends. It will be carried by an interplanetary station, whose task is to deliver the module to Venus and release it into the atmosphere upon arrival in the planet’s orbit. After that, the station will remain in orbit and will study the geological structure of the planet.
VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy). Its task is to map the surface of the planet (as far as possible in such a dense atmosphere and cloudiness). The system will be equipped with radar, which will help to break through to the surface. The device will be in the orbit of Venus. By the way, one of its tasks is to search for sources of infrared radiation, which gives scientists the opportunity to search for active volcanoes and tectonic plates. Scientists hope that they will be able to find analogues of ocean ridges and find other interesting details of the surface of Venus.
In general, until life on Mars was discovered, Venus still has a chance. Perhaps this planet will become the first planet, besides our own, where it will be possible to find life. One life, reasonable, will try to find at least some kind of “relatives”. I would like to hope that everything will work out.