We’ve just received the following message from the Herschel Project Scientist…
‘At around 10:54 UTC this morning the Herschel cryocover was commanded to open by manual commanding from the MOC here at ESOC.
The command was executed nominally, there is telemetry indicating that the cover reached the
open position, the shaking of the spacecraft caused by the opening was seen on the gyros and
the phase separator, and the temperatures at L0 and L1 slightly changed.
All of this is consistent with what you would expect from a successful cryocover opening. The
final positive confirmation will come from a measurement of the optical background as seen
by the PACS instrument which is underway.’
Short summary – the cryocover is open and PACS will soon be transmitting first light images on blank sky. I think a pointing at a bright famous object is expected to follow shortly after, but exactly what is seen will depend on how well the pointing is calibrated.
More news soon!