A short update from the Rosetta mission team at ESOC, still working today in the Main Control Room. We spoke a few minutes ago with Ignacio Tanco, deputy spacecraft operations manager, who reports that the spacecraft is doing very well, thank you!
- Rosetta is operating nominally; the network systems and overall ground segment to control the mission are nominal
- Last night, Rosetta lost contact with Philae as expected when it orbited below the horizon just after 20:00 CET.
- Contact was re-established this morning at 06:01 UTC / 07:01 CET, and the Philae-Rosetta radio link was initially unstable.
- As Rosetta rose higher above the Philae landing site, the link became very stable and the lander could transmit telemetry (status and housekeeping information) and science data from the surface.
- This morning’s surface link was again lost due to Rosetta’s orbit at about 09:58 UTC / 10:58 CET. Ignacio explains that with the current orbit, Rosetta will have, typically, two Philae communication windows per day.
- The next window opens at 19:27 UTC on the spacecraft and runs through to 23:47 UTC spacecraft time.
The team are ensuring that Rosetta maintains an orbit that is optimised for lander communication support; they are planning a manoeuvre (thruster burn) today to be conducted on Friday that will help keep Rosetta where it should be. Rosetta already conducted a burn last night as part of this effort.
Rosetta is presently sending signals to the ground stations at about 28 Kbps; Ignacio says that the spacecraft’s own telemetry downlink uses about 1 or 2 Kbps of this, so the rest is being used to download science data from Rosetta and lander science and telemetry from the surface.