Research presented at the European Planetary Society conference in Potsdam reveals that Venus was once as humid as Earth, but has lost the water
Observations by the European Venus Express spacecraft have provided new evidence that the solar wind has ripped large amounts of water from Earth's twin. The data also shed new light on the process of transport of trace gases in the Venusian atmosphere, and the pattern of the winds. The results were presented at the European Planetary Science Conference held in Potsdam, Germany last week.
The SPICAV and VIRTIS instruments on board the spacecraft were used to measure the water vapor concentrations in Venus' atmosphere at altitudes between 10 km and 110 km, far above the cloud tops. The studies led by researchers from Belgium and Russia revealed that the proportion of heavy water, which contains the isotope deuterium instead of hydrogen, and normal water is double at an altitude of 110 km compared to the values in the lower atmosphere.
"Water vapor is a rare species at all in the Venusian atmosphere: if it were in a liquid state today, it would pocket the surface of Venus with only another few centimeters of water. However, we believe that Venus had a large volume of water that has since escaped into space or been torn apart by the solar wind. These Monos Express results show that the heavy water could not escape the Venusian atmosphere as easily as normal water. This enrichment of heavy water provides new evidence of the loss of water occurring in the upper atmosphere, and that Venus was almost certainly moist in the distant past and more similar to Earth." said Dr. Emmanuel Mark from the LATMOS laboratory in France.
A team led by Mark also used SPICAV to study the variation in sulfur dioxide concentrations at different latitudes and found that there is a gradual decrease in the concentration of the gas towards the poles. "This corresponds to our knowledge about the movement of spirits" says Dr. Mark. "Energy coming from the sun is redistributed so that the air rises near the equator and descends towards the poles. We also see a decrease in the amounts of sulfur dioxide in the upper atmosphere, where the gas is broken down by the sun's ultraviolet radiation. In general, our measurements confirm the trend of decreasing sulfur dioxide concentrations since the first measurements carried out in the XNUMXs, indicating that there may be strong volcanic activity on Venus, although we have never directly observed it."
The VIRTIS and VMC instruments were also used to measure the wind speed at different heights by analyzing observations at different wavelengths. The tops of the clouds are at an altitude of 70 km and can be observed in visible and ultraviolet light on the day side of the planet. The lower atmosphere can be observed on the night side in the infrared frequencies that manage to escape the atmosphere despite the clouds.
Observations of the lower cloud layer over a period of two years showed that the wind strength is almost constant on days when there is no seasonal effect or variation related to the position of the sun in Venus' sky. The study led by Dr. Ricardo Huasso from Pais Vasco University, revealed variations in wind strength from time to time, especially in the sub-polar regions close to the 65 degree south latitude line. "The changes appear to be related to the polar cyclone that tends to affect latitudes distant from it, but we still do not know how to explain how the phenomenon occurs." says Dr. Huaso.
For information on the website of the European Planetary Society
3 תגובות
to 1. Logic says that at the time the planet was formed, the water evaporated from it because
The intense heat caused by the process on the one hand and the relatively low gravity at the time
the formation. That is: water reached Venus (like Earth) only in the phase after the formation.
Despite being a layman on the subject of the article, it seems that the findings reported in it are more in the form of faint hints than proof.
Based on the above findings, is it really possible to determine, with a high level of probability, that Nega was covered in water in the past?
According to what I know, the water on the surface of the Earth originates from comets and asteroids and not from the water that was in the planetary nebula at the time of its formation. When talking about the escape of the water from Venus, does it mean the same water that arrived in the second stage?