re: Herschel's mirror larger than Hubble's
"After Herschel, the L2 is the favoured position for Nasa's James Webb Space Telescope - Hubble's successor."
Damn ESA folks, taking up that L2 real estate ahead of Webb.
I have been psyched about this IRAS on super steroids for a while. Herschel's only problem is that because of the active cooling, it only has a few years lifetime as a far IR scope. Good luck to ESA!