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The orange color of a moon near the horizon (a “Harvest Moon”) is a true physical effect. It stems from the fact that – when you look toward the horizon – you are looking through a greater thickness of Earth’s atmosphere than when you gaze up and overhead. The atmosphere scatters blue light – that’s why the sky looks blue. The greater thickness of atmosphere in the direction of a horizon scatters blue light most effectively, but it lets red light pass through to your eyes. So a moon near the horizon takes on a yellow or orange or reddish hue.

You can see that when the Moon is near the horizon the light it reflects must travel through much more atmosphere, scattering light and making it appear more orange, yellow, or red.