Yesterday two major milestones were passed in making Planck operational.
Firstly the sorption cooler was switched on. This is needed to get the instruments, especially the HFI, to the temperatures needed for them to operate properly.
Secondly, the LFI, the Low Frequency Instrument, was switched on. We’ve not in a position to take science data with it yet, but the switch on went well, and the instrument replied that it is healthy.
Today will be spent making a course correction maneuver that will put Planck into orbit around L2. This burn will take 30 hours and use most of the fuel on board. So today is a big day!