alt Hacker NewsIf the manufacturing for the 2.4 meter mirrors existed a decade earlier, and Hubble used the existing processes, does that mean all the KH-11 satellites also have the spherical aberration problem that Hubble has?
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iririririr • yesterday at 10:20 AM
or hubble has the aberration because the design optimized for cost on that bandwidth, because nobody would ever need to zoom individual fibers on a newspaper page? remember those where pointed the other way around.
but that's an awesome rabbit hole you pointed out!
The spherical aberration of Hubble's main mirror was caused by a manufacturing defect.
Perkin-Elmer designed a new null corrector to verify that the mirror was made to spec, but the null corrector was incorrectly assembled (one of the lenses was out by a few mm). They also used the previous null corrector to test, which showed that the mirror was incorrectly ground, but decided that the new null corrector's measurements was correct.