In a new study, astrobiologists “blew off dust” from the old hypothesis that life can exist in the clouds of Venus.
In this work, a team of researchers, led by Sanjay Limaye of the University of Wisconsin in Madison, USA, suggests the existence of microorganisms in the atmosphere of Venus. The possible habitation of the Venusian clouds was first expressed by the biophysicist Harold Morowitz and the famous astronomer Carl Sagan in the distant year of 1967. A series of measurements carried out with the help of Venusian spacecraft between 1962 and 1978 showed that the temperature and pressure in the middle and lower parts the atmosphere of the planet (at altitudes of 40 to 60 kilometers above the surface) do not exclude the possibility of the existence of microbial life. On the surface of the planet, at the same time, the conditions are unfavorable for the existence of life, since temperatures there reach 450 degrees Celsius.
In his work Limai and his colleagues pay attention to the mysterious dark spots in the carbon dioxide atmosphere of Venus, observed in the ultraviolet and indistinguishable in other ranges. According to the authors of the work, these spots can represent colonies of bacteria fixing sulfur. These spots can retain their shape and position for several days, and the size of the spots is close to the size of the colonies of similar bacteria found on Earth.
As the authors of the study indicate, modern tools for studying the atmosphere of Venus do not allow distinguishing organic substances from inorganic ones, and therefore, to check the hypothesis put forward in the work. Therefore, in terms of testing its assumption, scientists are betting on the future space mission VAMP (Venus Atmospheric Maneuverable Platform), a probe that will be able to “hang” at the same level in the atmosphere of Venus for several months (up to one year), collecting samples, analysis which will determine the presence of microorganisms.