The Moon usually looks yellow because Earth’s atmosphere filters and scatters its light, especially when it is low on the horizon. The Moon itself is grayish, but the light that reaches your eyes has had much of its bluer component stripped away, leaving a warmer yellow-orange tint.

What color the Moon really is

  • The Moon’s surface is mostly a dark gray, made of rock and dust that reflect sunlight fairly weakly.
  • In space, without atmospheric effects, the Moon looks gray-white rather than clearly yellow.

How Earth’s atmosphere yellows the Moon

  • When moonlight passes through the atmosphere, molecules and tiny particles scatter shorter-wavelength blue light more than longer-wavelength red and yellow light (Rayleigh scattering). This leaves the direct light slightly depleted in blue, so it appears yellowish to us.
  • Extra dust, smoke, or pollution can increase this effect, making the Moon look deeper yellow, orange, or even red.

Why it looks more yellow near the horizon

  • When the Moon is low, its light travels through a much longer path of atmosphere before reaching you, giving more opportunities for blue light to be scattered away.
  • As the Moon rises higher in the sky, the path through the atmosphere shortens, scattering less blue light, so the Moon’s color shifts from yellow/orange toward pale white.

Other times the Moon changes color

  • During events like large wildfires or dust storms, added particles can make even a higher Moon appear unusually yellow or orange.
  • In a lunar eclipse, only redder sunlight bent through Earth’s atmosphere reaches the Moon, so it can look dark red, copper, or brown rather than simply yellow.

TL;DR: The Moon looks yellow mainly because Earth’s atmosphere scatters away some of the blue light in the moonlight, especially when the Moon is low on the horizon or when the air is dusty, so the remaining light reaching your eyes appears warm yellow instead of pure white.

Information gathered from public forums or data available on the internet and portrayed here.