Venus, the second planet from the sun, is often known as ‘Earth’s twin’ or ‘sister planet of Earth’, because of their similarity in size, mass and bulk composition. But due to its dense atmosphere, which composed of carbon dioxide with clouds of sulphuric acid traps heat and causes a greenhouse effect. Thus Venus became the hottest planet in the solar system, even though it is not closest to the sun. Because of its heavy atmosphere, the surface pressure is more than 90 times that of Earth. Also, the surface of Venus is extremely dry and covered with volcanoes.
Earlier Venus was considered as dead or a planet with no geological activities. Later the radar images taken by Magellan mission which scanned the Venus surface between 1990 and 1994 revealed mountain ridges and valleys converged to produce flat plains of cooled lava. Then the experts have spotted the signs of mountain ridge movements.
Now a recent study found 37 recently active volcanic structures on Venus. It provides proof for Venus being still geologically active. The study was conducted by researchers at University of Maryland and Institute of Geophysics at ETH Zurich, Switzerland, was published in the journal Natural Geoscience on July 20, 2020.
From previous studies, scientists got evidences of warm interior and coronae of Venus. Coronae are ring liked geologically activity spots on the surface of a planet, which forms when plumes of hot material deep inside the planet rise through the mantle layers and crust. This is similar to the way in which mantle plumes formed the volcanic Hawaiian Islands.
Although it was considered as the sign of ancient activity and the planet had cooled enough to slow down the geological activity in the interior and harden the crust, such that any warm material from deep inside would not be able to puncture through.
In the new study, researchers applied numerical models of thermo-mechanic activity under the surface of Venus to create high resolution 3D simulation of coronae. From the result researchers found features that are only present in recently active coronae. Also the result shows that, some of the variations in coronae across the planet represent different stages of geological development. Thus the study offers first evidences that the coronae of Venus is still evolving and the interior is still churning.
Laurent Montesi, a professor of geology at UMD and co-author of the research paper said,” This is the first time we are able to point specific structures and say, ‘Look this is not an ancient volcano but one that is active today, dormant perhaps, but not dead.’ This study significantly changes the view of Venus from a mostly inactive planet to the one whose interior is still churning and can feed many active volcanoes.” Montesi and his team are able to tell that at least 37 coronae have been recently active.
Active coronae indicate the areas where the planet is most active. It provides clues about the function of the planet interior. The active coronae in Venus are clustered in handful of location. So the result may help the future Venus missions to identify the target areas where geological instruments should be placed.
REFERENCE: University of Maryland
A 3D model of the surface of Venus.
Source: NASA Visualization Technology Applications and Development (VTAD)
Author
