Why does the Moon look red, yellow or blue? NASA explains its colours

Why does the Moon look yellow, orange, red and sometimes even bluish in different photographs? NASA's Astronomy Picture of the Day (APOD) for 1 November 2026 illustrates the variety of apparent lunar colours and explains the role of Earth's atmosphere.

The atmosphere changes the colours we see

When the Moon is low on the horizon, its light travels farther through the atmosphere. Shorter blue wavelengths scatter more strongly, leaving relatively more yellow and red light reaching an observer. Dust, smoke and other particles can further change its appearance.

An unusual bluish tint can occur under certain atmospheric conditions and particle distributions, but it does not mean the lunar surface itself has turned blue. During a total lunar eclipse, Earth blocks direct sunlight; light refracted and filtered through Earth's atmosphere still reaches the Moon, often making it appear copper-red.

NASA's original article features a series of photographs by Marcella Giulia Pace. They can be viewed via the source link below. The photograph used for this article is a separate, licensed illustration and is not part of the scientific photo series.

Photo: Mike Petrucci / Unsplash — an illustrative image of the Moon, not Marcella Giulia Pace's original photo collage.

Source: NASA Astronomy Picture of the Day, 1 November 2026: Colors of the Moon.