The December 28 mission utilizes an ST-A version of the workhorse Soyuz vehicle, with total payload delivery performance estimated at 3,723 kg. Liftoff is scheduled for 1:42 p.m., local time.

Designated as Flight VS25 in Arianespace’s numbering system, this will be the 25th launch of a Soyuz from French Guiana since its introduction at the Spaceport in October 2011, with CSO-2 to be deployed during a flight lasting just under one hour.

Rollout of Soyuz to the ELS launch complex

The Soyuz was transferred today from the MIK integration building to the ELS launch complex, situated in the Spaceport’s northwestern sector near the town of Sinnamary. Using procedures employed for the Russian-built launcher since it ushered in the space age, the Soyuz rolled out horizontally on a rail system aboard a transporter/erector. Once in the launch zone, it was raised into the vertical position above the pad’s massive flame trench – and was protected by a purpose-built mobile gantry.

This clears the way for the next step: rollout of the mission’s payload section for mating to the launcher.

Earlier in the preparations for Flight VS25, the CSO-2 satellite was fueled in the Spaceport’s S3B clean room preparation facility and integrated on the Soyuz launch vehicle’s Fregat upper stage. This was followed by encapsulation of the CSO-2/Fregat combination with the 11.4-meter-tall Soyuz ST payload fairing. The fairing was adorned with a stylized decal symbolizing the 3,560-kg.-class satellite in orbit with its four solar panels deployed, along with the placement of logos for the CSO-2 program’s key participants.

Arianespace will place CSO-2 into Sun-synchronous orbit for the French CNES (Centre National d’Etudes Spatiales) space agency and the DGA (Direction générale de l’armement) defense procurement agency, on behalf of the French Ministry of Defense. 

Building out France’s CSO satellite constellation

CSO-2 is the second satellite of the Optical Space Component (CSO – Composante Spatiale Optique) program, a constellation of three satellites dedicated to Earth observation for defense and security. They are being placed into polar orbits at different altitudes, and will carry out two missions: reconnaissance for CSO-1 and CSO-3; and identification for CSO-2.

Soyuz’ “upper composite” consists of CSO-2, the Fregat upper stage and payload fairing.

The predecessor CSO-1 spacecraft was orbited in December 2018 on an Arianespace Soyuz mission that also was performed from the Spaceport.

Airbus Defence and Space is prime contractor for the CSO satellites; Thales Alenia Space supplies the optical imaging instrument.

To be deployed at an orbit altitude of approximately 480 km., CSO-2 will acquire extremely-high-resolution images in the visible and infrared bandwidths, day or night and in fair weather, and using a variety of imaging modes to meet as many operational requirements as possible.

CNES is delegated as the contracting authority for the Optical Space Component program and mission ground segment, as well as being the overall system co-architect. It also is responsible for orbital positioning, in-orbit acceptance testing, and satellite operation. The DGA is the contracting authority for the construction and through-life maintenance of the user ground segment, and will serve as the interface between the sensors deployed in space and the operators. Operating authority for the CSO system is assigned to the French armed forces headquarters.

Decals for the CSO-2 satellite and its key program partners are installed on the Soyuz launcher’s payload fairing during activity in the Spaceport’s S3B payload preparation facility.

• Larger versions of the photos above are available for downloading in the Gallery.

Liftoff time for Soyuz Flight VS25:

More details are available in the Soyuz VS25 launch kit: