Zodiacal Light.

Sometimes the sky itself seems to glow. Usually, this means you are seeing a cloud reflecting sunlight or moonlight. If the glow appears as a faint band of light running across the whole sky , you are probably seeing the combined light from the billions of stars that compose our Milky Way Galaxy . But if the glow appears triangular and near the horizon , you might be seeing something called zodiacal light . Pictured above, zodiacal light is just sunlight reflected by tiny dust particles orbiting in our Solar System . Many of these particles were ejected by comets . Zodiacal light is easiest to see in September and October just before sunrise from a very dark location.