The European Space Agency (ESA) has just confirmed the development of its EnVision mission, which targets the planet Venus. This project will complement the other two announced by NASA last week. More than ever, Venus is back in the spotlight.
Long neglected, Venus will once again receive visitors. A few days ago, Bill Nelson, the new NASA administrator, announced the retention of the DAVINCI+ and VERITAS missions. Both finalists of the Discovery program, they will be launched at the end of the decade. But they won't be alone.
This Thursday, June 10, the European Space Agency announced the upcoming development of its own mission:EnVision , slated for launch in the early 2030s . Europe's last foray into Venus was a few years ago, with the Venus Express orbiter which surveyed the planet between 2006 and 2014 .
These next three missions will be complementary, each carrying different instruments with the aim of solving a common objective:to understand how this planet, once "Earth's twin", came to be. transformed into a hellish world.
With surface temperatures around 460°C (hot enough to melt lead), an atmospheric pressure more than 90 times greater than that of the Earth, and clouds of sulfur dioxide and particularly corrosive sulfuric acid, Venus indeed presents itself today as a veritable post-apocalyptic wasteland.
However, the data collected on site suggests that this was not always the case. Once upon a time, Venus was indeed very similar to Earth. But then, what happened? Why did these two planets, which started from the same starting point, follow different paths? These three new missions will have to answer these questions.
For its part, EnVision will carry with it radar systems capable of scanning the thick atmosphere of Venus, mapping both the surface and the rock layers up to thousand meters below the surface . An array of spectrometers sensitive to ultraviolet and infrared light will also analyze the chemical composition of the atmosphere and differentiate between the types of rocks on the ground.
Finally, a radio experiment will aim to rely on slight changes in the planet's gravity to analyze the layered structure of its geological innards.
The spacecraft will also be able to peer into Venus' past for scar tissue left by ancient plate tectonics and relics of its volcanic activity that may having triggered the greenhouse effect which dried up the planet.
Finally, these instruments will answer another major question:is Venus still geologically active ? Although most scientists suspect that this is indeed the case, the thick cloud cover that coats its surface makes it impossible to confirm this hypothesis. It is therefore essential to go directly to the site to completely dispel this uncertainty.
