Ariane V124 leaves the way clear for XMM launch
4 December 1999Although French Guiana's rainy season has officially arrived, there was not a cloud in sight on 3 December for the Ariane 40 which carried the Helios-1B reconnaissance satellite into orbit. The successful V124 flight allows the XMM campaign to move forward as planned.
For some of the members of the XMM team, it was the fourth opportunity to see a launch since their arrival in Kourou. The daytime liftoff provided some unique views of the launcher in a clear blue sky. Tracking cameras were able to clearly follow the ascent and even show the separation of the second and third stages! The flight was the 50th consecutive success for the Ariane-4 launcher since March 1995. It was rightly celebrated in Jupiter Mission Control with a large cake with icing and chocolate mousse and 50 'rocket candles' and sparklers.
Ariane-4 launch activity that day restricted operations on XMM to a minimum for safety reasons. But the purge of the inside of the spacecraft (with nitrogen for the Optical Monitor and synthetic air for the telescope tube), and the battery charging equipment were checked, as every day, in the launch table.
At the top of Ariane 504, the fairing is also permanently being flushed with a flow of fresh dry air (2000 cubic metre per hour at 16 °C) in order to maintain XMM at a constant 19 °C temperature.