Why Are Pictures of the Moon Always White?

Why the Moon Looks White

Color is determined by the frequency and intensity of electromagnetic radiation in the visible light spectrum (the light we can see). This energy reaches the optic nerve in our eyes and is interpreted by the visual centers of the brain as color. The moon looks white most of the time because its intensity is low and mostly constant. Low-intensity wavelengths are perceived as white. The same effect is at work when observing objects in a dark room, where we lose most of our color perception.

Pictures of the moon are usually white because, simply, that's how the moon looks most of the time. It also has to do with the fact that most cameras don't work as well in low light or darkness (when, of course, the moon is most visible). Tips for taking pictures of the moon including keeping the shutter open longer (to allow more light to enter the lens) and using a tripod (to stabilize the camera).

The moon sometimes looks red when particles in the atmosphere distort the light it gives off. While the sky appears "clear" to us, it's actually full of dust and other particles, which scatter the the light in different ways. Such particles block blue light in particular, which results in a greater proportion of red light getting through, thus imbuing the moon with a reddish hue.

The so-called harvest moon is associated with fall. During the year, the angle along which the moon rises and falls changes, which impacts how its light penetrates the atmosphere, and in turn, how it's perceived. While most pictures show the moon as white, some photographers capture its orangeish image at harvest time and other times during the year.