Astrophysicists from the United States and Germany have shown that sunlight penetrating through the clouds of Venus creates conditions for photosynthesis, similar to Earth, and chemical conditions create the possibility of microbial life. The article of scientists was published in the journal Astrobiology.
Researchers at the California Polytechnic University and the Technical University of Berlin, using a radiation transfer model, found that the lower and middle layers of clouds on the planet receive significantly – 87 percent – less ultraviolet radiation. Radiation in the UV-A range is 90 percent less intense there, and the most harmful components – UV-B and UV-C – practically do not penetrate there.
The chemical conditions for photosynthesis in clouds are also favorable, scientists say. According to their estimates, their lower layers may contain a lot of sulfur, as well as non-hazardous derivatives of sulfuric acid, such as ammonium hydrogen sulfate – which may indicate a greater availability of water for microorganisms and a lower acidity of the environment.
The researchers also found that photosynthesis on Venus can also occur at night – due to the energies of light and infrared radiation from the surface and from the upper atmosphere. In order to establish this, the scientists compared the flux of photons from these regions with that measured in habitats of phototrophic bacteria with low amounts of light, such as hydrothermal vents, for example. For Venus, it turned out to be larger.
Earlier, astronomers reported that mysterious traces of phosphine were found in the upper atmosphere of Venus. This compound is a waste product of living organisms, and scientists are not yet aware of other sources of poisonous gas.