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Each 10-meter Keck telescope reaches its full aperture using what arrangement?
AOne thick glass mirror disc
BTwo mirrors set end to end
CA ring of small lenses
D36 hexagonal mirror pieces
Answer & Solution
Correct answer: D. 36 hexagonal mirror pieces
1. A single 10-meter disc of glass would be far too heavy to hold in shape.
2. Each Keck telescope instead uses 36 hexagonal mirrors, each 1.8 meters wide.
3. Computer-controlled motors keep the 36 pieces aligned so they act as one surface.
4. The result collects light like a single mirror 10 meters across.
_Source: OpenStax Astronomy (CC BY 4.0), section 6.2 Telescopes Today_
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