Venus applies a rejuvenating lotion on herself

Research conducted at JPL NASA used data from the Magellan probe, which was sent to study Venus more than 30 years ago. Scientists decided to unravel the mystery of the dissipation of heat from the planet and how the Earth’s neighbor, devoid of tectonic plates, forms its surface.

Venus – the sister of the beautiful and infernal Earth

The data used in the study came from the Magellan mission, which was launched in 1989 to reach the orbit of Venus and explore our neighboring planet. It took Magellan more than a year to reach its goal, and within four years it became the first spacecraft to photograph the entire surface of the second planet from the Sun. In late 1994, the spacecraft was ordered to descend into Venus’ atmosphere, where it lasted about 10 hours before it burned up and contact was lost. Despite this, it ranks among NASA’s most successful space missions.

Magellan discovered that about 85% of the surface of Venus is covered by volcanic flows and there is no continental drift. The latter fact interested JPL scientists the most, who decided to use 30 years of data again. It was about how the crust of Venus loses heat as a result of its geological activity in regions called crowns. According to the researchers, this may happen in the same way as it did during the early stages of Earth’s tectonic activity.

Earth and Venus are rocky planets with roughly the same size and rock chemistry, so they must lose their internal heat by releasing it into space in the same way and at about the same rate. The hot core of the Earth heats the surrounding mantle, which in turn transfers this heat to the upper layers of the planet’s lithosphere. From there, heat radiates into space, cooling the upper regions of the Earth’s crust. This convection drives tectonic processes and keeps the tectonic plate puzzle moving. Venus, on the other hand, has no such plates at all, so until now the mystery of how it absorbs heat has been a mystery to scientists… well.

Venus applies a rejuvenating lotion on herself

Scientists looked at the halo seen in the images Magellan sent back and concluded that it forms where the planet’s lithosphere is thinnest and most active. Just as a thinner plate releases more heat than a thicker duvet, a thinner lithosphere allows more heat from Venus’ core to escape through plumes of molten rock pushed from the depths into the outer layers. Molten rock is released to the surface in the form of volcanic activity, actively shaping the surface of the planet.

Radar image from the Magellan mission showing circular fault patterns around the corona “Aine” in the southern hemisphere of Venus. Credit: NASA/JPL

To determine the age of a planet’s surface, planetary scientists use the method of calculating the impact of craters visible on its surface. In the case of a tectonically active planet like Earth, impact craters are continuously erased by plate subduction (and in the case of Earth, other factors such as plant growth and human influence). By counting the flower craters, the researchers concluded that the surface is relatively young. The research explains this condition with active volcanism in the regions of the many crowns, which is constantly “flattening” the terrain using the flow of magma from the planet’s interior.

Interestingly, Venus provides us with a window into the past that helps us better understand what Earth might have looked like more than 2.5 billion years ago. It is in a state we expect to occur before the planet forms its tectonic plates.
-Susan Smirkar, chief scientist at NASA’s Jet Propulsion Laboratory, JBL.

Source: sci.news, JBL NASA