The mission will move into action, after more than two years of defining the details of this orbiter which will lift the veil on the internal processes of Venus. Volcanism, cartography, exploration beneath the surface, there is still much to understand about the hell planet and its past.
It was two and a half years ago, in June 2021, that the European Space Agency chose its new mission around Venus, EnVision. Since then, the team in charge of the project has mobilized different scientific groups, defined exactly the role of the different agencies and the properties of each instrument that will be on board, so that the file is solid. Now that the ESA has given the green light and “adopted” EnVision, manufacturers will come into play through calls for tenders, to build this new orbiter then test it as much as possible before its departure for our neighbor in the Solar System, planned for 2031. A mission which will not be easy, even for its arrival in orbit! Indeed, EnVision should use the very precise method of aerobraking, which will consist of braking itself using the highest layers of the very dense atmosphere of Venus. Risky method, but which saves a lot of fuel, and especially since the ESA is the only one to have already tested around Venus with its previous mission, Venus Express.
Venus agrees, but how?
For its scientific objective, its reason for being, EnVision seeks to answer a question: when and how did Venus become so inhospitable? With its surface temperature of 464°C on average, it is pyrolysis every day (and one day lasts 355 Earth days on site…), all with a particularly dense atmosphere at ground level (90 bars) and clouds with high sulfuric acid content. However, on paper, Venus is something of a neighbor to Earth, with a comparable mass and size. So, EnVision will have to reveal how volcanoes, plate tectonics and asteroids made this planet the way it is, and whether it is still geologically active.
Precision instruments
EnVision will have several major instruments. It will observe rocks and volcanic massifs with a series of special spectrometers designed to pass through the atmosphere, called VenSpec. EnVision will map the surface using a large synthetic aperture radar, provided by NASA and capable of readings 10 times more precise than those of the Magellan mission (VenSar) and will have another radar, this time Italian and adapted to observations under the surface named SRS. Enough to detect possible ancient watercourses, pockets of materials under the surface or even magmatic reserves. Finally, the mission will carry a “classic” experiment on the gravity of the planet Venus using variations in radio data during exchanges with Earth, which should bring its share of discoveries on the deep internal structure and the core of the planet.
With more than 2.6 tonnes on the scale, this will be a major mission, which is already envisaged as a collaboration with NASA, not only via the radar instrument, but also with privileged and coordinated scientific data exchanges with the future vehicles of the American agency, which is preparing two missions (DAVINCI and VERITAS) towards the hell planet. Even if it is rumored that with budget concerns, NASA could remove one of the two…
Source : Esa
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