The Moon can appear orange or red when it is near the horizon because of the longer path that its light must take through the air before reaching the observer. Oxygen in the Earth's atmosphere scatters optical light with short wavelengths, and the effect, known as Rayleigh scattering, is more pronounced as light travels through more air. Particles in the air from smoke or dust accentuate the scattering of light.Continue Reading
The Moon emits no light of its own, and it simply reflects the sunlight striking its highly reflective surface. This light must then pass through Earth's atmosphere before it can be seen on the ground. Earth's atmosphere tends to scatter light from the blue end of the visible spectrum. This scattering effectively strips moonlight of its bluer wavelengths and makes it appear artificially reddened. The effect is difficult to notice when the Moon is high overhead, because its light travels through comparatively little air before reaching the observer and therefore scatters less than it does on the horizon.
If the Moon appears unusually red or orange or the effect persists while the Moon is overhead, it is possible that fine-grained particles of dust or smoke have saturated the atmosphere and are scattering the light more than normal.Learn more about Our Moon
Moon phases occur because the angle of the Earth, moon and sun changes as the moon orbits the Earth. One-half of the moon is always illuminated by the sun. As a person's angle of sight changes, different portions of sunlight and shadow are observed on the moon's surface.Full Answer >
Dust, smoke and pollution particles diffuse moonlight through the atmosphere to make it appear orange, red or yellow as the heavenly object rises or sets above the horizon. The atmosphere is thicker when viewing objects along the horizon rather than overhead, which also makes objects appear redder and larger. NASA calls this a moon illusion because the moon never actually changes color.Full Answer >
The moon appears orange when the sunlight it reflects passes through a thicker portion of the Earth's atmosphere. Generally, the moon only appears orange when it is close to the horizon.Full Answer >
Any time the moon appears orange in the sky, it's because of light diffusion and refraction in the atmosphere. When the moon is low in the sky, the blue light reflected from its surface is scattered in the dense atmosphere, giving the moon a reddish-orange cast.Full Answer >