Initial reports of success from the control room
We are off again; the team at the German Space Operation Center (GSOC) and their colleagues from EADS Astrium gathered two days ago in the control room to manage the transition to close formation flight. We began the first manoeuvre on Monday, 11 October 2010; this is referred to as the ‘drift start’ manoeuvre, which gives the TanDEM X satellite (TDX) the necessary momentum to close to a distance of one kilometre behind TerraSAR X (TSX) within a few days.
Beginning on Wednesday morning, we have resumed working in shifts and are monitoring the status of the two satellites with more than 15 contacts per day per satellite – that is, we have at least one contact per orbit with each satellite, in order to be able to intervene (almost) immediately in the event of trouble. We were able to enjoy our first success before the beginning of this morning’s shift at 09:00 local time – the ‘inter-satellite link’, which sends status data from TSX to TDX and makes it possible for TDX to react to problems, had already transferred its first data earlier in the day.
Meanwhile, the satellites have already closed to a separation of two kilometres, and we look forward to implementing the ‘drift stop’ manoeuvre with which we complete the approach phase. From this point, only a few small manoeuvres will be necessary to arrive precisely in the required formation.
Until then – that is, until Friday morning – we will be carefully monitoring every contact with the satellites from the control room. Once we can confirm that close formation flight has been achieved, we hope to return to normal working hours. But we will, of course, continue to keep a careful eye on TSX and TDX as the radar satellites continue their ‘dance’ together.