Light of Zodiac
The elongated cone-shaped zodiacal light is photographed from a dark site in central Iran. On the left the prominent constellation Orion and bright star Sirius are notable while the lights of the nearby city Kashan i much brighter than the zodiacal light on the other side and dominate the southwest horizon. Made by the sunlight reflection from dust particles in solar system plane, the zodiacal light is an unusual triangle of light visible along the ecliptic before dawn and after dusk under dark skies, specially in pre-dawn sky of late Summer and early Autumn and just after dusk in late winter and early spring (considered for northern hemisphere and opposite for the southern viewers). Zodiacal light is so bright at those mentioned time of year because the dust band is oriented nearly vertical at sunrise or sunset, so that the thick air near the horizon does not block it out.