A mirror 4 meters across gathers how much more light than one 1 meter across?

1. Light gathering depends on the collecting area, not on the width alone. 2. The area of a circle grows with the square of its diameter. 3. Going from 1 meter to 4 meters multiplies the diameter by 4. 4. Squaring that factor gives 4 times 4, which is 16. 5. So the 4-meter mirror collects 16 times the light of the 1-meter mirror. 6. The answer of 4 times uses the diameter ratio and forgets to square it. 7. The answer of 8 times would follow from cubing 2, which fits volume rather than area. 8. The answer of 32 times doubles the correct figure for no reason the geometry supports. _Source: OpenStax Astronomy (CC BY 4.0), section 6.1 Telescopes_