Last Friday, we had to say good-bye to our satellites as they were sealed from view within the Soyuz rocket fairing.

The encapsulation process followed another critical milestone, that of mating the Sentinel-1B to the Fregat upper stage.

Earlier in the week, the Fregat had arrived in the ‘S3’ building where the CNES Microscope satellite and the three CubeSats, which have been developed through ESA’s Fly your Satellite! Education programme, were waiting, already integrated in the ASAP-S launch adapter.

Once the Fregat had been accommodated in the ‘KMTO’ yellow scaffolding integration structure, the ASAP-S adapter with the host satellites was joined to the Fregat.

The next main job was to check all the connections in preparation for mating Sentinel-1B to the Fregat, and then finally mating could take place.

When the KMTO scaffolding was opened, it revealed an impressive set of satellites – all tested, all verified, all ready for space.

It was at this point that the teams started to get very excited.

Early Friday morning, the team went to the S3B building for a last glance of Sentinel-1B.

Several inspections ensured that the entire stack of Fregat, ASAP-S (the small satellites adapter) and Sentinel-1B was ready for encapsulation.

During the actual encapsulation process, those not directly involved in this hazardous operation had to leave the building and follow progress on TV monitors in other buildings.

Encapsulation started in the morning at around 10:00 and finished at around 14:00.

Afterwards a special team arrived to apply the various logos on the fairing. In its current configuration, Sentinel-1B forms part of the Upper Composite, which will be transported to the launch site and hoisted on top of Soyuz on Tuesday (19 April) afternoon.

Although the satellite is now within the fairing, other activities such as battery charging are being carried out and controlled remotely from the S5C building, meaning that some of the team has been working through the weekend.

The rest of us can relax and recover from the long working days – a last breather to ensure the team is well rested for the countdown rehearsals, Soyuz finalisation, and launch on Friday 22 April.

Photos of the encapsulation will follow.

From the team in Kourou.

For information about our Sentinel-1 mission visit www.esa.int/sentinel-1

For information about CubeSats Fly Your Satellite! visit: https://www.esa.int/Education/CubeSats_-_Fly_Your_Satellite