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:

    As night is withdrawn
    From these sweet-springing meads and bursting boughs of May,
    Dream, while the innumerable choir of day
    Welcome the dawn.
    Robert Bridges (1844–1930)

    Haven’t you heard, though,
    About the ships where war has found them out
    At sea, about the towns where war has come
    Through opening clouds at night with droning speed
    Further o’erhead than all but stars and angels
    And children in the ships and in the towns?
    Robert Frost (1874–1963)