Launch of the first satellites for ESA’s LEO-PNT demonstration mission Celeste

Bremen/Māhia, 28 March 2026. Today at 10:14 CET, the first two satellites of ESA’s LEO-PNT demonstration mission Celeste were successfully launched aboard an Electron rocket from the Māhia Launch Complex in New Zealand. The two small satellites (IOD-1 and IOD-2, IOD = In-Orbit Demonstrator), weighing 20 and 30 kilograms respectively, will test new navigation technologies in low Earth orbit (LEO-PNT = Low Earth Orbit – Positioning-Navigation-Timing). These capabilities are expected to pave the way for future applications such as indoor navigation and autonomous driving.

Europe’s current satellite navigation system, Galileo, consists of 30 satellites operating at an altitude of 23,222 kilometers in medium Earth orbit (MEO). While this configuration provides global coverage, it reaches its limits in dense urban environments, tunnels, or indoor settings. Due to the satellites’ distance from Earth, their signals are relatively weak, cannot always penetrate obstacles, and are vulnerable to interference such as jamming or spoofing.

To address these challenges, future navigation architectures will deploy satellites in multiple orbit layers and integrate them with ground-based systems, enhancing the accuracy and resilience of European navigation services.

Navigation constellation in low Earth orbit

ESA’s Celeste mission will demonstrate the performance of a navigation constellation in low Earth orbit. At this reduced altitude, satellite signals reach Earth with lower latency and higher power. 

The demonstration mission will be expanded gradually from 2027, with the successful launch of the first two demonstrator satellites marking an important initial milestone. The two spacecraft will secure frequency allocations and confirm the viability of the system concept.

The next step involves adding eight larger demonstrator satellites, each weighing around 90 kilograms. Beginning in 2027, they will test additional system functionalities, including signal transmission on previously unused frequencies. This will enable future navigation signals to be received indoors while also offering improved protection against manipulation.

ESA has commissioned the development of the demonstrator satellites for Celeste to two consortia, led by the Spanish technology company GMV and Thales Alenia Space in France, respectively. Within the GMV-led consortium, OHB is the core partner responsible for developing four of the larger demonstrator satellites, including their payloads, which are now in production in Bremen. For the GMV satellite launched today (IOD-1), OHB contributed two key payload components.

“Accurate positioning, navigation, and timing information from space is vital to Europe’s industrial base and critical infrastructure,” says Marco Fuchs, CEO of OHB. “Celeste LEO-PNT plays an important role in strengthening strategic independence. The successful launch of the first demonstration satellites is a significant step toward a fully functional constellation, and we are proud to help reinforce Europe’s resilience and sovereignty.”