Sentinel-3A is ready to be sealed from view inside the Rockot fairing so today we will be saying good-bye to our baby.

Sentinel-3A ready to meet fairing. (ESA-S. Corvaja)

Sentinel-3A ready to meet fairing. (ESA-S. Corvaja)

Most of yesterday was spent removing ‘non-flight protections’, i.e. items that do not go into space and have to be removed from the satellite. So this involved, for example, removing protective covers from the instruments and antennas. In addition, we also finalised the protective multilayer insulation around critical elements.

In parallel, Khrunichev finalised the multilayer insulation on the Breeze upper stage of the rocket and fixed all the electrical connections between the Breeze and the launch adapter.

Sentinel-3A atop Rockot upper stage. (ESA-S. Corvaja)

Sentinel-3A atop Rockot upper stage. (ESA-S. Corvaja)

Thales Alenia Space then switched on the satellite and did some electrical tests which that everything was all ok.

A meeting between the thermal experts clarified the thermal conditions and settings to be used when the satellite is at the launch pad.

The team also visited the vault to configure the NDIU router for the connections between ESA’s European Spacecraft Operations Centre ESOC, the satellite and our electrical ground support equipment for when the satellite is taken to the launch pad.

By about 16:00, Sentinel-3A was ready to meet the fairing. We then needed make sure that the clearance between the satellite and the fairing was ok. This is a critical point – especially since Sentinel-3 is the largest satellite to ever be launched on a Rockot. There is only clearance of 4–5 cm between the satellite and the inside of the fairing shells.

Sentinel-3A next to fairing half shell. (ESA-S. Corvaja)

Sentinel-3A next to fairing half shell. (ESA-S. Corvaja)

Anyway, on placing the fairing around the satellite we found, with some relief, all the clearance was ok and, in fact, there is some margin. The fairing was left closed for the night.

Today, we’re opening up the fairing again to do a few more things on the satellite but by noon the real ‘encapsulation’ will have happened – marking the moment we have to say good-bye to our satellite, well ‘visually’ anyway.

In conclusion, all remains GREEN for the launch!

Weather in Plesetsk: +1/0 °C, cloudy.

For information about our Sentinel-3 mission visit www.esa.int/sentinel-3

From the ESA Sentinel-3A team at the Plesetsk cosmodrome in Russia.