The horizon (or skyline) is the apparent line that separates earth from sky, the line that divides all visible directions into two categories: those that intersect the Earth's surface, and those that do not. At many locations, the true horizon is obscured by trees, buildings, mountains, etc., and the resulting intersection of earth and sky is called the visible horizon. When looking at a sea from a shore, the part of the sea closest to the horizon is called the offing. The word horizon derives from the Greek "ὁρίζων κύκλος" horizōn kyklos, "separating circle", from the verb ὁρίζω horizō, "to divide", "to separate", and that from "ὅρος" (oros), "boundary, landmark".

Read more about Horizon:  Appearance and Usage, Distance To The Horizon, Curvature of The Horizon, Projective Geometry

Famous quotes containing the word horizon:

    The bird is lost,
    Dead, with all the music:
    While sunsets heard the brain’s music
    Faded to last horizon notes.
    Owen Dodson (b. 1914)

    In expanding the field of knowledge, we but increase the horizon of ignorance.
    Henry Miller (1891–1980)

    The world of the egotist is, inevitably, a narrow world, and the boundaries of self are limited to the close horizon of personality.... But, within this horizon, there is room for many attributes that are excellent....
    Ellen Glasgow (1873–1945)