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Galileo: the journey of satellites 33 and 34

On 17 December 2025, two new Galileo satellites lifted off from Europe’s Spaceport in French Guiana. This was the 14th launch for Europe’s satellite navigation operational satellite programme, reinforcing Europe’s resilience and autonomy. The flight, VA266, was the first launch of Galileo satellites on Europe’s newest heavy-lift launcher Ariane 6.

The satellites, designated SAT 33 and SAT 34, separated from the launcher after a flight of just under four hours. The launch was declared successful after acquisition of signal and the confirmation that both satellites are healthy with their solar arrays deployed.

“With these new satellites, we strengthen Europe’s global navigation services - delivering greater precision, reliability and autonomy in space”, affirmed Andrius Kubilius, EU Commissioner for Defence and Space.

“Galileo stands as the world’s most accurate global navigation satellite system – and today we have increased its reliability and robustness,” said Josef Aschbacher, ESA’s Director General. 

The European Space Agency was responsible for carrying out the Galileo launch with Arianespace on behalf of the European Commission. The Galileo satellites were manufactured by OHB, under contract with ESA. Now in orbit, the EU Agency for the Space Programme (EUSPA) brings the satellites into service and oversees their operation.

Follow the launch campaign.

Introducing the 250 N ARIEL thruster

Spanish company Arkadia is developing a thruster called ARIEL (Attitude for Reusable and Innovative European Launchers). Many satellites and rockets have two types of engines, one for moving large distances and one for controlling their orientation, or attitude. This thruster has been developed to be part of a reliable and affordable Reaction Control System that adjusts orientation of space transportation vehicles.

ARIEL uses hydrogen peroxide as fuel which is more sustainable and less toxic than the hydrazine commonly used in most reaction control systems. It is one of the first hydrogen peroxide monopropellant thrusters of this size in Europe. Providing thrust of up to 250 N, it could suspend a 25 kg sack of cement on Earth, more than enough to orient a spacecraft or steer a rocket.

The European Space Agency (ESA) Future Launchers Preparatory Programme (FLPP) prepares European industry for the future space ecosystem, supporting companies with promising technology for the future. The first test firing was done just seven months after signing the initial contract in June 2023. The engine has now passed an extensive test campaign at the Arkadia Space Test Center in the Castellón airport, Spain, reaching technology readiness level six within two years from the contract signature.

The project includes tank prototypes that feed the ARIEL thrusters with its propellant, even operating in efficient ‘blowdown mode’ whereby the hydrogen peroxide gases in the tank push the liquid fuel to the engine.

Arkadia built a test bench inhouse to withstand the thrust and long burns over repeated cycles needed to thoroughly test ARIEL.

Throughout the campaign ARIEL proved itself by performing:

over 178 seconds of specific impulse in vacuum

continued steady firing up to 5 minutes

firing in short pulses of just 40 milliseconds

over 2000 pulses in total per engine

over 100 kg of hydrogen peroxide fired per engine

342nd Council: Media information session

Watch the replay of the media information session in which ESA Director General Josef Aschbacher and ESA Council Chair Renato Krpoun (CH) update journalists on key decisions taken at the ESA Council meeting, held at ESA Headquarters in Paris on 17 and 18 December 2025.

A first in space autonomy

The European Space Agency (ESA) has achieved a historic milestone, autonomous formation flying with millimetre-level precision.

“Proba-3 proves that bold in-orbit experimentation is essential to turning breakthrough ideas into real space capabilities. ESA does not just design innovation, it flies it,” explains Ian Carnelli, ESA Head of Systems Department.

With Proba-3, two spacecraft operate as one distributed system – fully autonomously, without guidance from Earth.

Powered by onboard autonomous vision and optical and laser metrology, they detect each other from kilometres away, rendezvous, and maintain an ultra-stable formation in orbit.

At the core of Proba-3:

Cooperative and non-cooperative navigation
Autonomous GNC and manoeuvring capability
On-board formation management
Autonomous safety & collision avoidance

The result
A virtual rigid structure in orbit, reconfigurable and resizable, with no continuous ground control or manual intervention. Just trusted onboard intelligence. Proba-3 is not a demo. It is a blueprint for next-generation space systems and represents how Europe is leading autonomous spaceflight.

“Proba-3 shows why in-orbit technology demonstration matters. ESA deliberately takes bold technical risks in space, pushes systems beyond what has ever flown before, and delivers. This is how ground-breaking technologies become operational capabilities, not on paper, but in orbit,” says Damien Galano, Proba-3 mission manager.

Replay: Galileo L14 launch coverage

On 17 December, two new Galileo satellites lifted off from Europe’s Spaceport in French Guiana aboard an Ariane 6 rocket. This marked the 14th launch for Europe’s satellite navigation operational satellite programme, reinforcing Europe’s resilience and autonomy.

The European Space Agency (ESA) is responsible for carrying out the Galileo launch with Arianespace on behalf of the European Commission. The Galileo satellites were manufactured by OHB, under contract with ESA. Once in orbit, the EU Agency for the Space Programme (EUSPA) will bring the satellites into service and oversee their operation.

The flight, designated VA266, was the first launch of Galileo satellites on Europe’s newest heavy-lift launcher Ariane 6.

Follow the launch campaign.

Galileo L14 launch highlights

On 17 December, two new Galileo satellites lifted off from Europe’s Spaceport in French Guiana aboard an Ariane 6 rocket. This marked the 14th launch for Europe’s satellite navigation operational satellite programme, reinforcing Europe’s resilience and autonomy.

The European Space Agency (ESA) is responsible for carrying out the Galileo launch with Arianespace on behalf of the European Commission. The Galileo satellites were manufactured by OHB, under contract with ESA. Once in orbit, the EU Agency for the Space Programme (EUSPA) will bring the satellites into service and oversee their operation.

The flight, designated VA266, was the first launch of Galileo satellites on Europe’s newest heavy-lift launcher Ariane 6.

Follow the launch campaign.

Proba-3 fills the solar observation gap

The ASPIICS coronagraph aboard ESA’s formation-flying Proba-3 mission is able to observe the Sun’s corona in the gap between the fields of view of solar extreme-ultraviolet imagers and conventional coronagraphs, making it uniquely suited for studies of the inner solar corona.

This time-lapse animation captures a coronal mass ejection (CME) in the top right, combining observations made on 16 July over a period of one hour and a half by three different European instruments aboard different missions: the Sun’s disc and low corona (artificially coloured in yellow), as captured by an extreme-ultraviolet telescope (SWAP) aboard Proba-2; the outer corona (in red) observed by the LASCO C2 coronagraph aboard SOHO; and the inner corona (in green), imaged in detail by Proba-3’s ASPIICS coronagraph, filling the gap.

Andrei Zhukov from the Royal Observatory of Belgium, Principal Investigator for the ASPIICS coronagraph on Proba-3, comments: “You can see the CME starting at the edge of the solar disc, captured by Proba-2. Then it extends into the inner coronal region, which is now visible to us thanks to Proba-3, before reaching the high corona observed by SOHO. The continuity with which we can now observe the CME structure extend outwards from the Sun is incredible.”

Galileo L14 liftoff on Ariane 6

On 17 December, two new Galileo satellites lifted off from Europe’s Spaceport in French Guiana aboard an Ariane 6 rocket. This marked the 14th launch for Europe’s satellite navigation operational satellite programme, reinforcing Europe’s resilience and autonomy.

The European Space Agency (ESA) is responsible for carrying out the Galileo launch with Arianespace on behalf of the European Commission. The Galileo satellites were manufactured by OHB, under contract with ESA. Once in orbit, the EU Agency for the Space Programme (EUSPA) will bring the satellites into service and oversee their operation.

The flight, designated VA266, was the first launch of Galileo satellites on Europe’s newest heavy-lift launcher Ariane 6.

Follow the launch campaign.

Ariane 6 for Galileo

Europe’s newest rocket Ariane 6 was made for Galileo.

This video shows a launch of two Galileo navigation satellites on an Ariane 6 rocket.

Ariane and Galileo have a long history together, with 12 satellites launched aboard three Ariane 5 rockets. Ariane 6, the new generation of Europe’s heavy-lift launcher, is taking over as the reference for launching Galileo satellites.

The world’s most precise satellite navigation system, Galileo serves billions of daily users from medium Earth orbit 23 222 km above Earth’s surface. Galileo is also making a difference across key sectors, including rail, maritime, agriculture, financial timing services and rescue operations.

On behalf of the European Commission, the European Space Agency (ESA) is responsible for the design, development and qualification of Galileo's space and ground systems as well as procuring the launches. The European Union Agency for the Space Programme (EUSPA) operates the satellites from the Early Orbit Phase of their operational mission until their disposal at the end of life.

Ariane 6 is a key element of ESA’s efforts to ensure autonomous access to space for Europe’s citizens. Its modular and versatile design allows it to launch all types of missions, from low-Earth orbit to deep space.

Ariane 6 is designed and built by ArianeGroup. It has three main components each working in stages to escape Earth’s gravity and take satellites to orbit: two or four boosters, and a core and upper stage. For this launch, the rocket will be in its two-booster configuration. 

The core stage and the boosters provide thrust for the first phase of flight. The core stage is powered by the Vulcain 2.1 engine (fuelled by liquid oxygen and hydrogen), with the main thrust at liftoff provided by the P120C boosters. 

The upper stage is powered by the reignitable Vinci engine, also fuelled by liquid oxygen and hydrogen. The upper stage will fire two times to reach the required orbit for this mission. 

After separation of the Galileo satellites, the Ariane 6 upper stage moves to a stable graveyard orbit far away from operational satellites.

ESA’s InCubed programme

InCubed is the European Space Agency’s Earth observation programme for ‘Investing in Industrial Innovation’. It aims to foster commercial innovation, boost the European Earth observation economy and reinforce relationships with the private investor community. It achieves this by working with entrepreneurs to develop innovative and commercially viable products and services that generate or exploit the value of Earth observation imagery and datasets. As a commercially driven programme run by ESA Φ-lab, InCubed exemplifies ESA’s role as a partner to industry and a supporter of business and technology innovation.

ESA highlights 2025

2025 was a landmark year for Europe in space. From celebrating 50 years of ESA to new missions, scientific breakthroughs, the year reaffirmed Europe’s leadership in science, exploration, climate action and innovation.

ESA Council meeting at Ministerial level 2025 - press conference

Watch the replay of the press conference held at the conclusion of ESA's Ministerial Council 2025 (CM25) in Bremen, Germany. ESA Director General Josef Aschbacher, as well as the hosting minister and the CM25 chair, present the outcome of this high-level meeting that took place on 26 and 27 November.

Download the press conference slides