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Depending on the time of year, there may be a period of an hour and half between total darkness and sunrise. At certain times, if the sky is very dark, it is possible to see a light on the horizon when according to a sky almanac it still should be totally dark. This light is called the zodiacal light or false dawn when it is seen before sunrise, although it can also be seen after sunset.
Unlike the ordinary light seen on the horizon near sunrise and sunset, the zodiacal light is shaped like a knife-blade thrusting our of the horizon and can be seen only from areas close to the equator, particular during the spring and autumn. The zodiacal is seen at times at which the sky is normally completely black. It is not formed by the reflection of light off the air of the atmosphere, but by tiny particles of interplanetary dust, and since the dust is concentrated in the ecliptical plane of the Solar System, the zodiacal light is also seen along the ecliptic.
If you are fortunate enough to be able to see the zodiacal light, check the opposite horizon also. You might be able to see an extremely faint light called the gegenschein or counterglow. The gegenschein, like its counterpart, the zodiacal light, is light reflected by interplanetary dust and lies along the ecliptic. One some occasions, there will be a hazy band of light connecting the zodiacal light to the gegenschein creating zodiacal band, indicating the band of the ecliptic containing both the constellations of the zodiac and the planets.