In March 2022, the European rover Rosalind Franklin of ExoMars was ready to be shipped to the Baikonur cosmodrome, for a liftoff in September using a Russian rocket before landing on Martian soil thanks to a lander, Russian too.

But the war in Ukraine had just broken out and in application of the sanctions imposed on Russia by its 22 member states, the European Space Agency (ESA) suspended the mission.

A shipwreck for hundreds of scientists invested for 20 years in this crucial project for the search for extraterrestrial life.

The shock was all the more severe as ExoMars was coming back from afar.

Launched in 2003, the mission quickly proved to be too expensive for Europe, which has never landed a robot on Mars.

The ESA then turned to the United States, which accepted a contribution... before NASA, forced to cut budgets, backtracked in 2012.

An unexpected partner then enters the scene: the Russian space agency Roscosmos.

Despite its support, in 2016, the mission suffered a major technical setback with the crash of the demonstration lander Schiaparelli, postponing the launch of ExoMars to 2020.

Difficult negotiations

The Covid-19 pandemic inflicts two more years of delay on the mission, which is finally weighed down by the invasion of Ukraine.

At the end of 2022, the ESA Ministerial Council decides to continue it with an extension of 500 million euros over three years, a minimum amount to keep the program alive.

"One of the key arguments to convince was to say that it is a unique European scientific work, of the same level of ambition as the James Webb space telescope", explained at the end of January David Parker, director of human and robotic exploration of the ESA.

The scenario is to build a European lander, for takeoff in 2028. A date that some do not believe.

Technicians work on the Rosalind Franklin rover of the ExoMars mission, February 7, 2019 in Stenevage, England © BEN STANSALL / AFP/Archives

ESA must first recover its equipment (on-board computer, altimeter radar, etc.) inside the Russian "Kazatchok" lander, still stuck at its assembly site in Turin, Italy.

Only the Russians know how to use it and difficult negotiations are underway to get them to dismantle it.

"We were expecting them in mid-January, they didn't come.... We asked them to have everything done by the end of March," Thierry Blancquaert, head of the ExoMars program, told AFP. ESA.

The new mission will depend on support from NASA, which has been ready to help since the invasion of Ukraine.

For its lander, ESA hopes to benefit from the American engines which made it possible to land the Curiosity and Perseverance rovers.

It will also need an American launcher suitable for transporting radioactive materials to keep the Rosalind Franklin warm.

"Traces of Life"

NASA has not yet voted the necessary budget, but "we are preparing the collaborative work together and things are progressing well", welcomed Thierry Blancquaert during the screening of a documentary on the mission, broadcast on National Geographic. .

The discussions are even more fluid than in the past.

"This new impetus in cooperation is linked to the fact that this time, the United States has a joint project with Europe, + Mars Sample Return +", analyzes planetary scientist François Forget, researcher at CNRS.

This program to return Martian samples to Earth, planned around 2030, will analyze the harvests from Perseverance and ExoMars, making the two missions complementary.

Image provided by NASA on September 10, 2021 of the Perseverance rover using one of its cameras on the Jezero crater on the planet Mars © Handout / NASA/AFP/Archives

"ExoMars is not just another rover, it is currently the only mission that can detect traces of past life," argues David Parker.

The robot is equipped with a single drill that can dig up to two meters underground, where potential traces of ancient organisms would be better preserved than on the surface, where Perseverance works.

The chosen landing site is also older than the lands already explored.

Its geology is closer to the period when conditions may have been conducive to the appearance of life.

"We think there was a lot of water there. It's another planet Mars to explore, so even in ten years the mission will not be obsolete", according to François Forget.

© 2023 AFP