Well we had a hint of spring weather over the Easter weekend, but winter seems to have returned bringing us wind and snow.  The weather aside, we have been busy ticking off items on the ‘to do’ list to make the Sentinel-3B satellite ready for liftoff on 25 April …. as well as enjoying the odd Easter egg or two!

First signs of spring. (ESA)

Over the last few days we’ve completed a number of things such as check the GPS units, check the onboard time synchronisation mechanisms and check the payload data-handling unit’s mass memory.

The satellite’s radar altimeter, the ocean and land colour instrument, and the sea and land surface temperature radiometer have had their ‘nominal and redundant chains with science data’ checked.

Easter eggs for all. (ESA)

Importantly, the propulsion team has checked the fuel tank by putting it under pressure to make sure that the ‘latch valve’ doesn’t leak. Since the pressure of the tank was taken to 23 bar, which is considered hazardous, the cleanroom was restricted essential personnel only. Once this was done, the team brought the pressure back down to 2 bar for another important test to check that that the satellite’s eight thrusters were also leak-tight. And, all is good.

Under pressure. (ESA)

Rockot upper composite. (ESA)

Meanwhile, the rocket upper composite has been rolled out to the launch pad and fitted onto the Rockot booster to test the electrics on the complete launch vehicle.

So, all in all a busy Easter … and everything is on track for the launch on 25 April.

The weather in Plesetsk snow, rain, and wind –9°C/+2°C

From the ESA Sentinel-3Blaunch campaign team in Plesetsk

Read more about the Sentinel-3 mission