Celeste’s first satellites launched to explore LEO-based satellite navigation

The two satellites – built respectively by GMV and Thales Alenia Space – were launched at 10:14 CET and separated from the launcher about an hour later. This marks the beginning of their early operations phase, during which mission control gets them ready for life in orbit.

The two satellites will validate core technologies and new signals and service capabilities and will bring into use the required frequencies in L- and S-band signals for the mission’s operational phase, in adherence to International Telecommunication Union regulations. Additional launches in 2027 will bring the mission to its full configuration of 11 spacecraft in orbit offering a wide range of experimentation opportunities in different frequency bands, user environments and applications.

“With this mission, we are exploring new frontiers for satellite navigation. Celeste will demonstrate how a satellite navigation constellation in low Earth orbit can complement Europe’s current Galileo system in medium Earth orbit. Celeste was among the first ESA missions to embrace a New Space-inspired development approach, enabling faster and more flexible deployment of satellites and technical capabilities, and ultimately ensuring Europe stays at the forefront of innovation in satellite navigation,” said ESA Director General Josef Aschbacher.

“Over the past two decades, satellite navigation has become integral to our society. Galileo and EGNOS are a European success today, fuelling our society, generating economic growth while ensuring our independence and security. With Celeste, ESA is ensuring that Europe continues to pioneer innovation in positioning, navigation and timing. The mission will demonstrate how a complementary layer in low Earth orbit can enhance Europe’s current navigation systems, making them more resilient, more robust, and capable of delivering entirely new services,” said Francisco-Javier Benedicto Ruiz, ESA’s Director of Navigation.

By flying closer to Earth, Celeste offers the opportunity for more robust signals and new frequencies. The mission will offer an in-orbit test bench for a broad range of applications, such as enhanced navigation capabilities for autonomous vehicles, railway, maritime, and aviation, increased availability in urban canyons and remote polar and arctic regions, enhanced positioning and messaging with emergency services during disasters, tracking of connected devices and Internet-of-Things applications, and even indoor navigation.

Following the demonstration activities, the Celeste in-orbit preparatory (IOP) phase, fully supported by ESA Member States at CM25, will leverage European industry to validate the technologies in-orbit and build pre-operational infrastructure. Ultimately, the results of the Celeste mission will prepare European industry and support the European Union’s decision towards the establishment of an operational navigation layer in LEO, complementing Galileo and EGNOS, Europe’s current position, navigation and timing systems.

About Celeste

The Celeste mission is ESA’s initiative for LEO-PNT (Low Earth Orbit Positioning Navigation and Timing) and is currently in its in-orbit demonstration phase. This first phase features a demonstration constellation of 11 satellites that will fly in low Earth orbit to test innovative signals across various frequency bands. Its goal is to advance satellite navigation concepts for resilient positioning, navigation and timing services.

The Celeste in-orbit demonstration phase was approved at ESA’s Council at Ministerial Level of 2022. The fleet is being developed through two parallel contracts respectively led by GMV (ES) with OHB (DE) as core partner, and by Thales Alenia Space (FR) as prime and Thales Alenia Space (IT) as space segment responsible. The two consortia involve over 50 entities from more than 14 European countries.

Celeste was further expanded at ESA’s Council at Ministerial Level of 2025 (CM25), towards the implementation of the next phase: the LEO-PNT In-Orbit Preparatory phase.

Celeste also contributes to one of the three core pillars of ESA’s new European Resilience from Space (ERS) initiative, endorsed at CM25. ERS addresses critical security and resilience needs for Member States while laying the groundwork for future European strategic space capabilities.

For more information, visit www.esa.int/Celeste/.