After repeated delays and the loss of its Russian-built missiles, Europe’s ExoMars rover has been relaunched, in 2028, ministers agreed last week. The rover was scheduled to depart for the Red Planet in September on a Russian Proton rocket and land on a Russian-built craft until the European Space Agency (ESA) cut ties with Russia following its invasion of Ukraine. At a budget meeting last week, ESA decided to launch the mission on a yet-to-be-determined US rocket and develop its own lander – with some help from NASA.
“This is fantastic news for science and for the search for signs of life elsewhere,” said Andrew Coates of University College London, principal investigator (PI) of a panoramic camera on the rover. “It’s a positive thing: we still have a mission,” adds Valérie Ciarletti of the University of Paris-Saclay, PI of the rover’s ground-penetrating radar. The golf cart–size rover, named Rosalind Franklin after the British DNA pioneer, carries a sample collection drill that can penetrate up to 2 meters underground, where signs of ancient life can be preserved from radiation and other harsh surface conditions.
The announcement came at the end of a budget meeting of ESA’s 22 member states that takes place every 3 years. Ministers approved €16.9 billion in funding over the next five years for science, exploration, missiles, Earth observation and telecommunications. The nearly 17% increase over the previous budget was less than ESA management had asked for, and some programs will come under pressure. But the $2.7 billion — a 16% increase — going to the exploration program is enough to revive the ExoMars program, which has included multiple Mars missions.
The first phase of the project brought the Trace Gas Orbiter to Mars in 2016, as well as a landing demonstrator called Schiaparelli, which failed less than a minute before landing due to a software bug that disabled landing rockets too early. Rosalind Franklin, ESA’s first rover on the surface of Mars, would follow in 2018.
Problems pairing the rover with the Russian-made lander called Kazachok delayed the launch by 2 years. (Mars windows occur about every 2 years, when the planets align.) Then the lander’s parachutes, as well as the solar panels and wiring, caused problems, forcing another delay to 2022. Then in March, with Kazachok and Rosalind Franklin ready to go , war intervened.
When building a new Russia-free landing system, “we’re not starting from scratch,” said Thierry Blancquaert, ESA’s ExoMars team leader. Most components on Schiaparelli worked flawlessly, and ESA supplied – and can reuse – some of the systems on Kazachok, including the parachutes, radar, radio communications and the onboard computer. Engineers will now remove it from the Russian lander, which will remain in Italy, where it would be docked with the rover when Russia invaded. But no European manufacturer makes the kind of thrusters needed to gently bring the 310-kilogram Rosalind Franklin to the surface. This is where NASA comes in, says Blancquaert. It has offered to buy the thrusters from an American manufacturer.
NASA can also provide radioisotope heaters, power packs that use the decay of plutonium-238 to keep the rover from freezing during the frigid Martian nights. If so, US regulations require the heaters to fly on a US launch vehicle, which would most likely be a SpaceX Falcon-Heavy or a United Launch Alliance Vulcan Centaur. NASA would not confirm details of its involvement, but Eric Ianson, the agency’s program director for Mars Exploration, said in a statement: “NASA and ESA are planning important talks in the coming months regarding a possible collaboration for ESA’s ExoMars Rosalind Franklin rover mission, depending on the availability of US funding.”
Two other rovers — NASA’s Perseverance and China’s Tianwen-1 — have a head start of nearly a decade. But an ESA study found that the science ExoMars will provide after it lands in 2030 is still worth investigating, especially research using its deep drill. There is no doubt for the scientists involved: “No mission can replace ExoMars,” says Ciarletti.
The real losers of the new scheme are scientists – both Russian and European – who designed instruments to mount on the Kazakh lander. Due to the tight schedule for the development of the new ESA lander, it will not be doing science. “I feel very discouraged because of the current geopolitical situation,” said Francesca Esposito of the Astronomical Observatory of Capodimonte, who built a dust sensor for the earlier lander. “But I’m very happy that this hasn’t stopped this great mission.”