Material from the plumes could well up through the fractures as magma, according to the study.Īt the same time, slabs of surface rock could dip, or subduct, under the rims of the larger patches of rock sitting on top of the pillars - a process the scientists called "plume-induced subduction." In these experiments, the simulated mantle plumes could fracture the mostly rigid surface. Similar "mantle plumes" are seen on Earth. These experiments suggested that on Venus, mushroom-shaped plumes of hot rock rising up from the mantle can rest under patches of the Venusian surface, the researchers said. They dried these fluids from above to simulate the way the Venusian surface cooled and hardened over time, and heated these fluids from below to simulate the way the planet's hot interior would cause rock to circulate. In the experiments, glass tanks were filled with fluids loaded with particles of silica, the same material from which sand and glass are usually made. These findings hint that the surface of Venus is not as stagnant as scientists previously thought. Now, laboratory experiments simulating Venus support the idea that plumes of hot rock ascending up the planet's mantle layer could help explain these coronae. The round shape of these coronae suggested that they formed because of pillars of hot rock ascending up from underneath them, but trenches seen around them also indicated that rock was sinking beneath their upraised rims. These coronae "appear to be unique to Venus," Fabio Crameri, a researcher at the Centre for Earth Evolution and Dynamics at the University of Oslo in Norway, wrote in a commentary accompanying the study published online April 10 in the journal Nature Geoscience. These features consist of a round central region, often surrounded by cracks in the surface or streaks stretching out from the center, creating a feature that looks like a crown from above. However, previous research also found that the surface of Venus has quasi-circular structures known as coronae. Scientists will continue the data analysis and retrieval to understand the phenomenon, which is very important to clarify the complex chemical processes and cycles at work in the atmosphere of Venus under the influence of solar radiation.The surface of Venus, revealed by probes that peer through the planet's thick cloud layer. However, Venus Express has revealed the presence of carbon monoxide as low as the cloud-layer top. In fact, Venus Express has already spotted the presence of an oxygen (O2) airglow high in the atmosphere. The incoming solar radiation dissociates this molecule into carbon monoxide (CO) and oxygen in the upper atmospheric layers. Venus’ atmosphere is mainly composed of carbon dioxide (CO2). In the colour scheme shown in the image at right, the brighter the colour (that is, the more radiation comes up from the lower layers), the less cloudy is the observed area.ĭuring capture orbit, preliminary data about the chemical composition of the atmosphere were also retrieved. The first infrared images making use of the ‘windows’ show complex cloud structures, all revealed by the thermal radiation coming up from different atmospheric depths.
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