A team of geophysicists from the Scripps Institution of Oceanography (University of California, San Diego) has explained the origin of mysterious structures on the surface of Venus, known as coronae. This discovery has been key to understanding why the planet, known as Earth’s “sister,” has evolved in a radically different way. The results of the study are published in the journal Proceedings of the National Academy of Sciences.
\Venus has long attracted the attention of researchers with its unusual surface. Instead of tectonic plates, like on Earth, it has a single solid crust scattered with hundreds of round or oval formations ranging from tens to hundreds of kilometers in diameter. They are called coronae because they resemble rings or hoops. In images from orbit, the coronae sometimes look like hills, and sometimes like giant “collapsed” soufflés. They are one of the most mysterious features of Venus, as there are no analogues to these structures on Earth.
To find an explanation for these structures, researchers conducted a series of computer simulations and concluded that the crowns are caused by hot magma plumes rising from the mantle. This is reminiscent of plumes – giant columns of molten rock that form, for example, the volcanic islands of the Hawaiian archipelago on Earth.
At the same time, Venus has a significant feature. At a depth of about 600 km, there is a transition layer where the crystalline structure of rocks changes. It acts as a “glass ceiling”: large plumes can break through this barrier and create giant volcanic uplifts, while smaller ones stop and spread under the surface, forming crowns. This explains why there are so many such structures on the planet and why they have different shapes.
“What surprised us most was the behavior of magma at depth. It literally ‘lines up’ under the barrier until one of the bubbles finds its way up,” notes lead author Madeline Kerr.
Thus, the new model helps scientists figure out why Venus lost its chance to become a “second Earth.” After all, the fate of these planets turned out to be opposite: while Earth developed conditions favorable for life, Venus turned into a scorching hell with an atmosphere saturated with carbon dioxide and temperatures above 460 °C. In addition, the study opens up new perspectives for studying the evolution scenarios of other planets and searching for worlds similar to it.
“This discovery is comparable to the significance of plate tectonic theory for Earth. We are only beginning to understand how the second closest planet to the Sun works,” explains Professor Loretta O’Neill.
To confirm or refine this model of crown formation, several new missions will study Venus in the coming years: NASA’s VERITAS and DAVINCI (launch expected in the 2030s), as well as Europe’s EnVision. They will be able to collect more data about the planet’s surface and internal structure.
