The zodiacal band is zodiacal light extending along the whole ecliptic. It is thought to be caused by the reflection of the sunlight from particles of dust and ice in the solar system, and is best seen during twilight in spring and before sunrise in autumn, but as it is very faint, the moon and light pollution usually mean it is unable to be seen even at these times.
Zodiacal light is a cone of light above the sunrise or sunset point on the horizon. In the northern hemisphere it is best seen in the weeks around the September equinox in the east before dawn. Because of this, it is often called the false dawn because it makes the sky look brighter, much like dawn. In the Southern hemisphere the September equinox is the best time to see the zodiacal light in the west after dusk when it is called the false dusk. Unlike true dawn or dusk, Zodiacal Light lacks any rosy colour. This is because the reddish skies of dawn and dusk are caused by the Earth's atmosphere, but the Zodiacal Light originates outside our atmosphere.
The best chance to see it is in a dark sky around the time of a new moon and around an equinox. That is because the light follows the ecliptic, ie. the pathway of the Sun, Moon and planets, which makes its most extreme angles with the horizon around the equinoxes. It makes its steepest angle on spring evenings (autumn mornings) and its narrowest angle on autumn evenings (spring mornings).
Because it follows the ecliptic, Zodiacal Light is often visible from Earth's tropical latitudes where the ecliptic hits the horizon at a steep angle all year long. Zodiacal Light is sunlight reflecting off dust grains in the inner solar system and it is thought these came from Mars, with grains from the dust storms escaping Martian gravity. These grains of dust range from micron- to metre-sized and this interplanetary dust also contributes to Gegenschein.
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