European Earth Return Orbiter reaches design maturity

Today, the critical design review for the spacecraft platform was completed with the cooperation of European industry and NASA.

A critical design review is one of the most important phases in any space project to make a spacecraft a reality. The Platform Critical Design Review (P-CDR) confirmed the performance, quality and reliability of the systems for this unprecedented mission to Mars.

The Earth Return Orbiter (ERO) is ESA’s main contribution to the Mars Sample Return campaign, a complex choreography of missions to return Martian rocks, soil and atmospheric samples to Earth.

Europe ready for Mars

The validation of the design and technical details constitutes a formal step towards the integration phase.

“The European industry is ready for the next chapter. A robust design is the basis for building, testing and assembling the hardware into a complete spacecraft,” said Tiago Loureiro, ERO project team leader.

Production and testing of the spacecraft components can now begin to ensure the mission can be launched.

Suppliers from eleven European countries are on board to build the components for an orbiter that can make a full return trip from Earth to Mars.

The challenges

NASA announced plans in April to revamp its Mars Sample Return program to reduce complexity, risk and cost, using innovative designs and proven technology to bring valuable samples back to Earth from Mars.

ESA’s technical teams worked closely with their NASA colleagues to prepare a review of the programme.

“The spacecraft configuration is robust enough to be flexible with the payload and to help find solutions for a new architecture. ESA and our industrial partners adapted to a new scenario, remained inventive and resourceful, while remaining a reliable partner for NASA,” Tiago explains.

“We have confirmed that the Earth Return Orbiter delivers what was planned and even more, whatever the alternatives,” he adds.

The magic

The Earth Return Orbiter’s essential mission is to bring samples from Mars back to Earth. But before it can do that, the spacecraft must first find those samples in space.

ERO’s design has proven with flying colors that it is capable of accommodating a basketball-sized capsule filled with samples collected by NASA’s Perseverance rover.

“This mission is an example of European technological prowess at its best. From a dizzying distance of hundreds of millions of kilometres, teams on Earth will choreograph a complex orbital dance around Mars,” said Orson Sutherland, ESA’s Mars Programme Manager.

Their challenge: find a tiny capsule, maneuver it into the correct orbit for the rendezvous, and successfully capture it—all while operating remotely across the vast expanse of space.

During ERO’s five-year mission to Mars and back, the spacecraft will also serve as a communications hub with rovers and landers on the surface.

European excellence

Teams in Europe rely on already mature technologies in autonomous navigation, rendezvous and docking, expertise built over decades from missions such as the Automated Transfer Vehicle and Europe’s first mission to Jupiter with JUICE. Knowledge from the ExoMars Rosalind Franklin rover mission to the Red Planet is also being incorporated.

ERO will be the largest spacecraft ever built for interplanetary flights. Contributions come from France, Italy, Germany, the United Kingdom, Spain, Switzerland, Norway, Denmark, Belgium, Romania and the Netherlands.

Airbus Defence and Space is responsible for the ERO mission, building the spacecraft and conducting mission analyses from France, Germany and the UK. Thales Alenia Space will play a key role in assembling the spacecraft, developing the communications system and delivering the orbit insertion module from its facility in Turin, Italy.