ESA Launches Celeste IOD-1 and IOD-2 Navigation Satellites
Why in the news
The European Space Agency (ESA) launched the first two satellites of its Celeste programme on 28 March 2026. They test whether navigation signals from low Earth orbit (LEO) can strengthen Europe’s existing systems.
Key facts
- Satellites: IOD-1 and IOD-2, weighing about 20 kg and 30 kg.
- Launch: Rocket Lab Electron rocket from New Zealand, 28 March 2026.
- Orbit: 500-560 km altitude.
- Purpose: a LEO layer to complement Galileo (medium Earth orbit) and EGNOS.
- Builders: GMV (Spain) and Thales Alenia Space (France).
Mission plan
| Item | Detail |
|---|---|
| Full demonstrator | 11 operational spacecraft plus one spare |
| Further launches | From 2027 |
| Goal | Better accuracy, resilience and coverage of positioning, navigation and timing |
About the technology
The satellites aim to show stronger L- and S-band signals and autonomous orbit determination that does not depend on ground infrastructure.
Exam angle
- Remember the programme name (Celeste), the agency (ESA) and the launcher (Electron).
- Galileo is Europe’s navigation system in medium Earth orbit; Celeste adds a LEO layer.
- PNT stands for positioning, navigation and timing.