Zodiacal light
Zodiacal light is a faint glow of sunlight reflected by dust in the plane of the Solar System.
Zodiacal light is a faint, cone-shaped glow that rises from the horizon along the ecliptic after evening twilight or before morning twilight. It is sunlight scattered by countless tiny dust grains, mostly between about 10 and 300 micrometres across, spread through the inner Solar System.
It is best seen from dark sites far from city lights. In the northern hemisphere, the best times are evenings in spring and mornings in autumn, when the ecliptic stands steeply above the horizon. In the tropics it can be seen at most times of year. A faint patch opposite the Sun, called the gegenschein, can sometimes be seen too.
The dust comes mainly from comets, particularly Jupiter-family comets, with some from colliding asteroids. Grains slowly spiral towards the Sun, and some are swept up by Earth. Many micrometeorites collected from Antarctic snow and from rooftops are probably members of the same cloud that produces the zodiacal light.
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