Science · 6 pages · 12 min
Why the Moon looks larger near the horizon
The horizon Moon looks larger because of perception, not because the disk has grown.
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From the opening
The Moon looks larger near the horizon because of a perceptual effect, the Moon illusion, not because the Moon has moved closer or swollen in the sky. Photographs made with the same lens show the low Moon and the high Moon at essentially the same angular size. The opening covers why the enlargement is perceptual, what refraction actually does, and how a fixed sight compares.
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Inside
- Why the enlargement is perceptual
- What refraction actually does
- How a fixed sight compares
- What a closer orbit adds
- Where the idea stops applying
- A distinction worth keeping
Sources
- The Moon illusion in visual perception
- Atmospheric refraction versus true angular size