Euclid to Set off with SPACEBEL Software for the Dark Universe aboard an Arianespace Launcher

At the beginning of January 2020, ESA confirmed the departure of the Euclid mission into Space from mid-June 2022 onwards and appointed Arianespace as the official Euclid launch operator.

Named after the Greek mathematician Euclid of Alexandria (~ 300 BC), the father of geometry, and built by Thales Alenia Space, prime contractor, the satellite will be launched either on an Ariane 62 rocket or a Soyuz rocket from the European Space Centre in Kourou, French Guiana.

The stakes are high: through the study of galaxies at different distances from Earth, determine the nature of the Universe as well as the reason for the acceleration of its current expansion. In addition, Euclid will enable us to unravel the mystery of the dark matter and dark energy of the cosmos. The innovative Space observatory weighing about 2 tons is conceived for a lifespan of minimum 6 years.

Since 2015, SPACEBEL has been in charge of the development of the subsystem control and data management software, i.e. highly critical functions that will contribute to the faultless functioning and success of this emblematic mission.


The Control and Data Management Unit Application Software (CASW) developed by SPACEBEL consists of the Execution Platform Software (EPSW), with its Interaction Layer, and of the Application Software (APSW) properly said.

  • The EPSW relies on the Basic Software (BSW) that includes the Real Time Operating System (RTOS) and that integrates the Hardware Dependent Software (HDSW), which provides for input/output (I/O) access. It encompasses a set of generic services such as a comprehensive implementation of the Packet Utilisation Standard (PUS) and a powerful On Board Control Procedure (OBCP) solution, to mention a few. It also implements the Unit Managers that manages and provides access to the various on board subsystems.
  • The so-called Application Framework (AFW), aka Interaction Layer, offers the access to the EPSW service to on board applications.
  • The APSW contains the specific applications software components that manage the system and the mission such as the Thermal Control, the Power Management, the Telemetry, Tracking and Command (TT&C) Management or the Payload Management. It also integrates the Attitude and Orbit Control System (AOCS) algorithms and it implements high level logic for overall system control with System Mode Management, Fault detection, isolation, and recovery (FDIR) and  System Safeguarding Logic (SSL).
new illustration Euclid to Set off with SPACEBEL Software for the Dark Universe aboard an Arianespace Launcher

Euclid at the L2 Lagrange Point©ESA - ATG Medialab