Getting a satellite ready to be launched involves a long list of jobs, but with Sentinel-3B now fuelled, this particular ‘to do’ list is significantly shorter. And, importantly, all is on track for liftoff on 25 April!

Concentrating on the job in hand (credits: Thales Alenia Space)

Since hydrazine is extremely toxic, only specialists dressed in bulky astronaut-like suits remained in the cleanroom for the duration of the activity. 

After fuelling, the tank was pressurised to an ‘intermediate level’ and left to stabilise overnight. The following day, the team gradually increased the pressure to the required level.

Upon confirmation that there were no hydrazine traces in the air, the fuelling lines could be disconnected and the decontamination phase started. The fill and drain valves have been closed, torqued to the flight value and wire-locked. The drums with the remaining hydrazine have been moved, ready to be taken back to their container.

On the launcher side, the Breeze started the first part of its fuelling yesterday, and it will be completed today.  All the activities are so far fully nominal.

The weather in Plesetsk sunny -2 / +5 degrees

From the ESA Sentinel-3B launch campaign team in Plesetsk

Read more about the Sentinel-3 mission