The brightness of zodiacal light decreases with distance from the Sun. In naturally dark night skies, the glow is visible as a band along the entire zodiac, completely straddling the ecliptic. In fact, zodiacal light spans the entire sky and largely contributes to the total natural light in a clear and moonless night sky. Another phenomenon – a faint but slightly brighter oval glow – directly opposite of the Sun's direction is the gegenschein, which is caused by backscattered sunlight.
In the mid-latitudes, the zodiacal light is best observed in the western sky in the spring after the evening twilight has completely disappeared, or in the eastern sky in the autumn just before the morning twilight appears. The zodiacal light appears as a column, brighter at the horizon, tilted at the angle of the ecliptic. The light scattered from extremely small dust particles is strongly forward scattering, although the zodiacal light actually extends all the way around the sky, hence it is brightest when observing at a small angle with the Sun. This is why it is most clearly visible near sunrise or sunset, when the sun is blocked, but the dust particles nearest the line of sight to the sun are not. The dust band that causes the zodiacal light is uniform across the whole ecliptic.
The dust further from the ecliptic is almost undetectable except when viewed at a small angle with the sun. Thus it is possible to see more of the width at small angles toward the sun, and it appears wider near the horizon, closer to the sun under the horizon.