After completing the analysis of data collected by satellites, "Pioneer Venus" and "Venus-Express", the researchers concluded that Venus from time to time there are volcanic eruptions, changing the composition of the atmosphere of the planet.
The results of the study, which was conducted by French experts from the laboratory LATMOS in collaboration with Russian scientists Denis Belyaev Institute of Space Research, presented in a paper published in the journal Nature Geoscience.
The presence of volcanoes on Venus indicates a significant amount in the atmosphere of sulfur dioxide (SO2). On Venus, the gas, as on Earth, where its concentration is less than one million times, in all probability, is of volcanic origin. Scientists, however, for a long time could not determine whether the volcanoes of Venus in force or whether they died out long ago, throwing SO2.
The authors managed to work to answer this question by analyzing the observations of the device "Venus Express", which was launched by the European Space Agency. Sputnik by the spectrometer SPICAV fixed constant decrease in the concentration of sulfur dioxide present in the upper atmosphere of Venus, from 2006 to 2012. This, say the researchers, suggests that in August 2006, shortly before the arrival of spacecraft into orbit of Venus, it happened on a number of powerful eruptions.
This has resulted in the release of large amounts of sulfur dioxide, a small amount of which was leaked just above the dense layer of clouds. Molecules of SO2, which is below this layer is protected from solar radiation and therefore may exist infinitely. However, outside the sulfur dioxide is oxidized rapidly, leading to a reduction in the upper atmosphere of Venus concentrations of SO2 (from 1 to 0,1-02 ppm) in the period from 2007 to 2011.
A similar phenomenon has been observed companion "Pioneer-Venus", who worked in the orbit of Venus in 1980. Then, in the period from 1980 to 1986, the concentration of SO2 above the cloud layer has fallen from 0.5 to 0.1 ppm. Hence, the authors concluded that Venus at least once a decade, there are eruptions of volcanoes. In this case, sulfur dioxide goes into the upper atmosphere of Venus, then gradually disappearing.