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Aligning Webb's mirrors.

(Science Week, Day 2!)

Now that Webb has reached its wide orbit around the sun, it's time to align its eighteen, interlocking, hexagonal mirrors!

On a recent press conference, I'd heard one staffperson say the expected initial misalignment was sub-millimetric. Highly slight, but enough to render an image of one distant star off the Big Dipper as a cluster of eighteen points of light, one per mirror. My inward question was: when this thing is eventually tuned and focused, what fraction of a degree will its field of view be? The video segment doesn't state it outright, but shines a little light on a first impression.