By Stephanie Dwilson | 2025-11-07

The European Space Agency (ESA) has taken a significant step toward building a satellite system that can send quantum keys across space, paving the way for European Union (EU) countries to share sensitive material with extreme security.

Once completed, the security and cryptographic mission (SAGA) will enhance the resilience of Europe's digital infrastructure and protect against potential threats by providing a post-quantum security layer.

The ESA has awarded a 50 million Euro ($57.4 million) contract to Thales Alenia Space to create a preliminary design (Phase B2) for the SAGA mission.

This covers the system definition and preliminary design of a fully European end-to-end quantum key distribution (QKD) system for governmental use.

This satellite QKD is just one element of the European Commission’s European Quantum Communication Infrastructure (EuroQCI), which aims to develop secure quantum communication protocols for the EU on the ground and in space.

'Truly secure connectivity'

Phase B2 is expected to take two years, after which the ESA will begin SAGA’s manufacturing phase.

The goal of SAGA is to develop a secure quantum key distribution service that operates via a low earth orbit QKD satellite, four access nodes across Europe, and a control segment that integrates with the terrestrial EuroQCI component.

"With SAGA, our aim is to ambitiously advance satellite communications," said ESA connectivity and secure communications director Laurent Jaffart.

The goal is to further "Europe’s digital sovereignty, cybersecurity and industrial competitiveness in the quantum era," he said in an October 1 statement.

"We are delighted to strengthen our partnership with Thales Alenia Space, which puts our member states at the forefront of the race for truly secure connectivity," he added.

Satellites in this communications infrastructure will "allow quantum signals to travel over vast distances, overcoming the limits of fiber-optic networks and making global-scale quantum communication possible," per Thales Alenia.

SAGA, first announced in 2019, is supported by space agencies in Italy, Germany, Austria, Spain, the Netherlands, France and Switzerland, with more expected to join as the mission continues.

Thales Alenia Space -- a global space manufacturer that designs, operates and delivers satellite-based systems for governments, institutions and companies -- has coordinated previous phases the SAGA mission as well, starting in 2020.

Thales Alenia Space is a joint venture between two public companies, the French Thales Group and the Italian firm Leonardo.

Protecting data, communications

SAGA is one of two components that will make up the EuroQCI, which will use quantum physics to secure everything from personal data to critical infrastructure like power grids and emergency services once it is operational.

The technology also will be able to detect any attempts by hackers to eavesdrop on confidential communications.

EuroQCI will work through two systems: ground-based fiber optic internet cables with quantum security enhancements, and a space-based satellite constellation that expands the reach of the QKD system.

SAGA is the mission advancing the latter part of the EuroQCI project, and marks a key step forward in Europe’s quest for technological independence, Thales Alenia Space CEO Hervé Derrey said in a statement.

The first satellite (Eagle-1) that will be part of the QKD system is slated to launch in 2026, carrying a quantum-key payload, and will remain in orbit for three years.