The first two satellites forming part of the European Space Agency's (ESA) Celeste mission were launched this weekend. Among other things, this mission is testing the use of satellites orbiting in low-Earth orbit (LEO) to complement the existing European Galileo system, which orbits in medium-Earth orbit. The satellites were launched on 28 March on an Electron rocket from the Rocket Lab Launch Complex in Māhia, New Zealand. The launch marks the start of Celeste's in-orbit demonstration phase.
The Galileo system is a European global satellite navigation system. It is an alternative to US GPS, Russia's GLONASS and China's BeiDou. Galileo was developed by the European Union (EU) in cooperation with ESA. Among other things, the system enables position, navigation and timing with higher accuracy than GPS.
Test bed for innovative technologies
Celeste is a new ESA project aimed at testing innovative technologies for future navigation satellites. Celeste stands for 'Cooperative and Efficient Low-Earth orbit Satellite TestbEd'. The project is part of ESA's European Resilience from Space (ERS) initiative, which aims to strengthen the resilience and security of European space capabilities.
The project includes testing new technologies that can be integrated into future generations of Galileo satellites. For example, Celeste is investigating how satellites in lower Earth orbit can contribute to navigation. Satellites flying closer to the earth can bring several benefits. For instance, it can provide stronger signals, but also make new frequencies in the L- and S-band usable. Interests include applications in urban environments, at high latitudes and for critical infrastructure such as railways and aviation.
There is also a focus on sustainability. It is being investigated whether this would be more efficient and environmentally friendly than Galileo's current medium earth orbit (MEO).
Celeste IOD-1 and IOD-2
The two satellites now launched are Celeste IOD-1 and IOD-2. The satellites have been developed by two European consortia:
- GMV (Spain) with OHB (Germany) as core partner
- Thales Alenia Space (France) as prime contractor with support from Thales Alenia Space (Italy)
In total, more than 50 organisations from 14 European countries are involved in the consortia.
Nine more launches planned
Nine additional Celeste satellites will be launched from next year. The constellation of 11 satellites in total should then enable various experiments in different frequency bands, user environments and applications.
