The planets move in mysterious ways. Or at least their surfaces do. The Earth has a tectonic plate system that drives the movement of its crust. This plate tectonics is ultimately driven by the flow of matter in the mantle – the layer directly below the crust. Now scientists have found a slightly different deformation mechanism on our nearest sister planet – Venus.
The research, conducted by Dr Paul Byrne of North Carolina State University and his colleagues, used data from NASA Magellan spacecraft that visited Venus in the 1990s. Orbiting the planet, the probe collected a radar map of its surface, which is obscured by a thick atmosphere at wavelengths visible to the human eye.
In one part of this radar map, the researchers noticed something interesting – a series of boulders where the planet’s crust (known as “lithosphereâ) Seemed to have moved. This discovery went against conventional wisdom of Venus, that the lithosphere of Venus was stationary.
As any good scientist knows, if the data disproves an old theory, a new theory is needed. So the team set out to model the deformation to see if they could figure out what could have caused it. The answer seems to be that the deformation is caused by the slow movement of the interior of the planet.
What’s more, the researchers also believe that the process that caused these deformities may still be ongoing. Venus has active volcanoes which are another way its surface warps. These volcanoes form lava plains, relatively young in geological terms. Some of these lava plains showed signs of deformation in Magellan’s data, implying that, even after being recently resurfaced due to volcanic activity, Venus’ lithosphere is again deformed by its active interior.
This active interior causes deformations that interact in the same way as ice caps that break and jostle on top of each other. Sometimes these even create small ice caps or jagged patterns, and the resulting stampede resembles what the researcher saw on the lava plains of Venus.
Fortunately, they won’t be the last to watch – a group of three new missions will be visiting our sister planet in the decades to come. They will be equipped with new and improved sensors, including one (VERITAS) whose main mission is to accurately map the surface of the planet. He will no doubt see the formations found by Magellan, but maybe higher resolution data will lead to even more information.
Learn more –
NCSU – “Ice floe” tectonics reveal the geological secrets of Venus
PNAS – A globally fragmented and mobile lithosphere on Venus
BBC – Signs of geological activity found on Venus
Technology review – Scientists may have spotted tectonic activity inside Venus
Main picture –
Photo of one of the large boulders in the Venus Lowlands they found, known as the NÃ¼wa Campus
Credit – Paul K. Byrne and Sean C. Solomon