Night

Night or nighttime is the period of time between the sunset and the sunrise when the Sun is below the horizon. This occurs after dusk. The opposite of night is day (or "daytime" to distinguish it from "day" as used for a 24-hour period). The start and end points of time of a night vary based on factors such as season, latitude, longitude and timezone.

At any given time, one side of the planet Earth is bathed in light from the Sun (the daytime) and the other side of the Earth is in the shadow caused by the Earth blocking the light of the sun. This shadow is what we call the darkness of night. Natural illumination is still provided by a combination of moonlight, planetary light, starlight, diffuse zodiacal light, gegenschein, and airglow. In some circumstances, bioluminescence, aurorae and lightning can provide some illumination. The glow provided by artificial illumination is sometimes referred to as light pollution because it can interfere with observational astronomy and ecosystems.

Read more about Night:  Duration and Geography, On Other Celestial Bodies, Impact On Life

Famous quotes containing the word night:

    The day in his hotness,
    The strife with the palm;
    The night in her silence,
    The stars in their calm . . .
    Matthew Arnold (1822–1888)

    A man was to live in that egg-shell day and night, a mile from the shore.... Think of making your bed thus in the crest of a breaker! To have the waves, like a pack of hungry wolves, eying you always, night and day, and from time to time making a spring at you, almost sure to have you at last.
    Henry David Thoreau (1817–1862)

    This is the Night Mail crossing the Border,
    Bringing the cheque and the postal order,
    Letters for the rich, letters for the poor,
    The shop at the corner, the girl next door.
    —W.H. (Wystan Hugh)