ESA confirms new space mission to probe Venus’s surface and below

The EnVision orbiter is designed to help scientists get a better understanding of the planet’s inner core and its upper atmosphere, in order to determine how and why Venus and Earth evolved so differently.

“A new era in the exploration of our closest, yet wildly different, Solar System neighbour awaits us,” says Günther Hasinger, ESA director of science. “Together with the newly announced Nasa-led Venus missions, we will have an extremely comprehensive science programme at this enigmatic planet well into the next decade.”

The team hopes to answer why Venus experienced such dramatic climate change which left it with a toxic atmosphere filled with thick sulphuric acid-rich clouds. They also want to discover whether the planet is still geologically active and whether it could once have hosted an ocean capable of sustaining life.

EnVision will cost around €610m (£525m) and comes equipped with a suite of European-built instruments including a sounder to reveal underground layering, and spectrometers to study the atmosphere and surface.

British researchers from Royal Holloway, University of London, the University of Oxford and Imperial College London will be involved, comparing geologic and atmospheric processes to those on Earth and other planets.

The spectrometers will monitor trace gases in the atmosphere and analyse surface composition, looking for any changes that might be linked to signs of active volcanism. A Nasa-provided radar will image and map the surface while a radio science experiment will probe the planet’s internal structure and gravity field as well as investigate the structure and composition of the atmosphere.

The instruments will work together to best characterise the interaction between the planet’s different boundaries – from the interior to surface to atmosphere – providing an all-encompassing global view of the planet and its processes.

The ESA team will work with Nasa’s upcoming DAVINCI+ and VERITAS missions, announced earlier this month, to build up a comprehensive understanding of the planet.

With the planet’s surface temperatures rising above 471°C, coupled with an extremely acidic atmosphere, previous landers have only lasted around two hours at the very maximum being malfunctioning. This has given scientists only limited glimpses beyond the planet’s atmosphere in the past.

The next step for EnVision is to move to the detailed ‘Definition Phase’, in which the design of the satellite and instruments is finalised. Following the design phase, a European industrial contractor will be selected to build and test EnVision before it is launched on an Ariane 6 rocket. The earliest opportunity for EnVision to launch is 2031, with other possible options in 2032 and 2033.

It will take around 15 months to reach the planet, with a further 16 months to achieve orbit circularisation through aerobraking.

UK science minister Amanda Solloway said: “I’m proud that once again British scientists have been chosen to play a leading role in a mission that will expand humankind’s understanding of the universe.

“It is fascinating to consider just how many similarities Venus shares with our Earth, and what its secrets could tell us about our climate as well as what makes our planet so special to be able to sustain life.”