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Earth Return Orbiter around Mars
Science & Exploration

Europe’s Earth Return Orbiter reaches design maturity

05/07/2024 3537 views 26 likes
ESA / Science & Exploration / Human and Robotic Exploration

ESA’s Earth Return Orbiter, the first spacecraft that will rendezvous and capture an object around another planet, passed a key milestone to bring the first Mars samples back to Earth.

The critical design review for the spacecraft's platform was completed today with the involvement of European industry and NASA.

ERO's engineering qualification model
ERO's engineering qualification model

A critical design review is one of the most important phases in any spaceflight 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 major contribution to the Mars Sample Return campaign, a complex choreography of missions to bring martian rock, soil and atmospheric samples back to Earth.

Europe ready for Mars

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

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

Earth Return Orbiter solar array
Earth Return Orbiter solar array

The manufacturing and testing of the components of the spacecraft can now start to ensure the mission moves ahead for launch.

Suppliers from 11 European countries are on board for building the parts of an orbiter set for a full round-trip from Earth to Mars.

The challenges

NASA announced plans to update the Mars Sample Return programme last April with reduced complexity, risk and cost, including innovative designs and proven technology to return valuable samples from Mars to Earth.

ESA technical teams worked closely with their NASA counterparts to prepare for a revision of the programme.

Bringing Mars rock samples back to Earth
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“The configuration of the spacecraft is robust enough to be flexible with the cargo and to help finding solutions for a new architecture. ESA and our industrial partners adapted to a new scenario, staying inventive and resourceful while remaining a reliable partner for NASA,” explains Tiago.

“We have confirmed that the Earth Return Orbiter works for what was planned to do and more, whatever the alternatives are,” he adds.

The magic

The Earth Return Orbiter has the essential role of bringing samples from Mars back to Earth, but before doing that, it must find them in space.

Earth Return Orbiter lens
Earth Return Orbiter lens

ERO’s design demonstrated with flying colours that it is capable of capturing a basketball-sized capsule filled with samples collected by NASA’s Perseverance rover.

“This mission exemplifies European technological prowess at its finest. From a staggering distance of up to several hundred million kilometres, Earth-based teams will choreograph a complex orbital dance around Mars,” says Orson Sutherland, ESA’s Mars programme manager.

Earth Return Orbiter captures Mars samples
Earth Return Orbiter captures Mars samples

Their challenge: to locate a tiny capsule, maneuver into the precise orbit for rendezvous, and successfully capture it – all while operating remotely across the vast expanse of space.  

ERO’s five-year mission to Mars and back will also see the spacecraft acting as a communication relay with rovers and landers on the surface.

European excellence

Teams in Europe rely on already mature technologies in autonomous navigation, rendezvous and docking, an expertise built up over decades from missions like 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 feeding into it.

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

Earth Return Orbiter infographic
Earth Return Orbiter infographic

Airbus Defence and Space has overall responsibility for the ERO mission to build the spacecraft and to conduct mission analysis from France, Germany and the UK. Thales Alenia Space will play an important role in assembling the spacecraft, developing the communication system and providing the orbit insertion module from its plant in Turin, Italy.