THE ZODIACAL LIGHT
Of all the astronomical phenomena visible to the naked eye, the zodiacal light is one of the most delicate. It appears as a diaphanous wedge oflight, no brighter than the Milky Way, extending up from the horizon well after sunset.
The glow is faint and you can easily see dim stars through it. In fact, even its most "brilliant" display is often mistaken for sunset glow or uplightmg from a nearby city or town.
The zodiacal light occurs when sunlight scatters oft the countless dust particles that orbit the Sun in a great disk. Like the planets, the dust particles are confined to the ecliptic—the plane of the Solar System. The constellations through which the ecliptic passes are collectively known as the zodiac, and since this is where the light is concentrated, it is called the zodiacal light.
Because the zodiacal light is aligned along the ecliptic, it reaches a higher altitude when the ecliptic is steeply inclined to the horizon. In middle-latitude locations, it is best seen in the west after nightfall during the local spring, and in the east before dawn during the local fall. In the tropics, where the ecliptic is more often nearly perpendicular to the horizon, the zodiacal light can be seen throughout the year in both the evening and morning sky.
To observe the zodiacal light, find a dark-sky location away from city lights. Give your eyes about 20 minutes to grow accustomed to the dark. Scan along the ecliptic from west to east, looking for a slight difference in brightness between the darker sky and the border of the zodiacal light. If it is not immediately visible, try using averted vision and look for the zodiacal light out of the corner of your eye.