We’ve now been told that the cryocover will be opening on Sunday, with first light data from the Herschel instruments coming down to us on Monday.
If the cryocover doesn’t open then that’s it – no science. It is what they call a ‘single point failure mode’. However, the cover’s mechanism has been extensively tested so it should work. In fact you can see a slow motion video of such a test here:
This is a test on an identical cryocover that had been kept closed for two years, and it worked perfectly. Still, some of us will be feeling quite nervous until we hear news of first light. Cross your fingers for us!