After a saga of broken promises, a European rover finally has a ride to Mars

NASA confirmed Thursday that SpaceX will launch the European Space Agency’s Rosalind Franklin Mars rover, perhaps as soon as late 2028, on a Falcon Heavy rocket from Kennedy Space Center, Florida.

So why is NASA deciding which rocket will launch a flagship European Mars mission? It’s a long story involving the search for extraterrestrial life, crippling political hatchets, and of all things, Russia’s invasion of Ukraine.

You can trace the history of Europe’s Rosalind Franklin mission back a nearly a quarter-century. A few years after NASA landed its first rover on Mars in 1997, the European Space Agency came up with a plan to send its own mobile robot to the red planet. The European rover was part of a program named Aurora, and officials hoped to launch it in 2009. Russia would have supplied a Soyuz rocket to send the rover on its way.

Stops and starts

“Delays ensued and plans changed,” ESA officials wrote in a 2016 fact sheet on the mission. This has become quite the understatement. What was originally a mostly European project, renamed ExoMars, became the centerpiece of a joint initiative with the United States in 2009, when NASA and ESA signed an agreement to pursue the exploration of Mars together.

The European rover was to fly to Mars in tandem with a similarly-sized US rover in 2018. A landing system based on the Jet Propulsion Laboratory’s “sky crane” architecture would deliver both rovers to the surface of Mars at the same time. A European orbiter designed to sniff out traces of methane in the Martian atmosphere would launch in 2016, two years before the rovers. NASA agreed to launch the 2016 and 2018 missions on a pair of United Launch Alliance Atlas V rockets.

But NASA pulled out of the agreement less than three years later. The Obama administration canceled most of NASA’s participation in ExoMars in 2012, citing budgetary constraints such as cost overruns with the James Webb Space Telescope. ESA had its own funding limitations, and could not afford to replace NASA’s launch and landing system contributions on its own.

Instead, the agency turned to Russia to launch the orbiter and rover on two Proton rockets and provide the descent system to deliver the rover to Mars. In exchange, ESA agreed to add Russian science instruments to the orbiter and rover missions. This was a boon for Russian scientific institutions. Without an international partnership like ExoMars, they lacked any realistic prospect of ever sending their own research payloads to the red planet.

Russia successfully launched the European-built ExoMars Trace Gas Orbiter spacecraft on a Proton rocket in 2016. The orbiter is still operating around Mars today, returning scientific data and serving as a communications relay for NASA’s Curiosity and Perseverance rovers. A small European tech demo probe riding piggyback on the orbiter crash landed upon reaching the red planet.

Artist’s illustration of the Rosalind Franklin rover departing its landing platform on Mars.

Credit: Airbus

Additional delays pushed the the launch of the ExoMars rover from 2018 until 2020. The rover, by then named for the late British chemist and DNA research pioneer Rosalind Franklin, was nearly ready for launch in 2020 when a series of parachute test failures and the COVID-19 pandemic prompted another delay until late 2022.

Everything changed again when Russian forces invaded Ukraine in February 2022. ESA severed most ties with Russia’s space agency, ending the partnership on ExoMars after all of the mission’s elements, including the Russian rocket and Mars descent stage, were already built and ready for final assembly. ESA also removed two Russian science instruments from the mission.

Once again, the US government stepped in to give the Rosalind Franklin rover a ride to Mars. NASA and ESA formalized the new agreement in 2024, with the US side committing to provide a launch vehicle, the braking engines needed to land, and small nuclear-powered heaters to keep the rover’s sensitive electronics warm during Martian nights. NASA long ago delivered a mass spectrometer for the European rover that will analyze Martian soil to look for markers of organic molecules.

ESA is providing the rover and the carrier spacecraft to ferry it to Mars. Europe is also responsible for the overall assembly of the landing platform and operating the rover on the Martian surface. Airbus built the rover in the United Kingdom and is supplying the main structure for the lander, which will settle onto Mars and deploy ramps for the rover to disembark and begin its mission. The German company OHB manufactured the carrier spacecraft, or cruise stage, to shepherd the rover from Earth to Mars. Thales Alenia Space of Italy is in charge of putting all the pieces together and readying the mission for launch.