The CSO-3 military observation satellite has been successfully launched by Arianespace atop an Ariane 6 from Europe’s spaceport in French Guyana (on March 6, 2025 at 1:24 pm local time in Kourou, 4:24 pm UTC, 5:24 pm CET). Carrying a very-high-resolution optical instrument built by Thales Alenia Space (TAS), the joint-venture between Thales (67%) and Leonardo (33%), the satellite was developed by prime contractor Airbus Defence & Space for the French defense procurement agency DGA on behalf of the French Air and Space Force’s Space Command, with delegated oversight from the French space agency CNES.

The third and last component in the CSO system for France’s MUSIS (Multinational Space-based Imaging System for Surveillance, Reconnaissance, and Observation) military program, CSO-3 will provide increased coverage and revisit capabilities to enable more effective conduct of military operations and faster crisis response.

Designed to the most stringent intelligence and defense requirements, CSO-3 is equipped with a cutting-edge instrument developed by Thales Alenia Space. This instrument is the core of the mission, affording
resolution and detail of Earth’s surface. Its performance enables it to acquire imagery at extremely high resolution, even in low-light conditions and at night thanks to its infrared capabilities. Its advanced technologies include latest-generation optical systems and ultra-sensitive sensors.

Like for the previous Helios 1, Helios 2 and Pleiades satellites, Thales Alenia Space designed strategic equipment for the CSO system, including the solar arrays, very-high-throughput image telemetry systems, and encryption/decryption modules to ensure data security and confidentiality. The company also supplied the system's telemetry, tracking and control transponders.

See for details AVIONEWS.