‘The baby cries!’ We have a satellite in space …!
But first things first – here the events of the first 100 minutes: L +00:00:00 (04:14:03 CEST)
‘Lift off’ – the Dnepr is ejected from its silo by a gas generator and the launcher’s engines ignite to begin the flight into orbit in a southerly direction.
L +00:04:42 (04:18:45 CEST)
Second stage separation.
L +00:15:25 (04:29:28 CEST)
Separation of the satellite from the upper, third stage of the launch vehicle. One and a half seconds earlier, the umbilical connecting the satellite to the launcher was disconnected by the firing of its pyrotechnic fasteners and the TanDEM-X onboard computer started up.
MET +00:00:00 (04:29:28 CEST)
With the separation, the mission officially begins. We relate events that occur from now on to this time and speak of the ‘Mission Elapsed Time’, or MET. The liberating message from Baikonur confirming the successful separation arrives and calms us somewhat, but only after the first radio contact with the satellite will we really be able to breathe again.
MET +00:15:52 (04:45:20 CEST)
‘The baby cries!’
We have first contact via the Troll ground station in Antarctica.
In the control room, spontaneous applause breaks out the tension falls away from us – the first major hurdle has been cleared. The spacecraft is in range of Troll for nine minutes and we can read on our monitors with great joy that the baby is ‘healthy’. All data are in the ‘green’ area. That is, temperatures, voltages, rotation rates and many other items of status information are within the allowable tolerances. As with Troll, contact data from the O'Higgins ground station, also in the Antarctic, will be received – and a further indication that the separation was successful and the satellite is in its intended orbit will be provided.
MET +01:10:15 (05:39:43 CEST)
After the last contact, we have had to wait about 40 minutes for further messages from TanDEM-X, because, from the Antarctic, the satellite had to cross the Pacific Ocean travelling north until the visibility area for the Svalbard (Spitsbergen) ground station was reached. This contact confirms the previous good news and colleagues in the control room have relaxed smiles ...