Day length, or length of day, or length of daytime, is the time each day from the moment the upper limb of the sun's disk appears above the horizon during sunrise to the moment when the upper limb disappears below the horizon during sunset. Due to the diffusion and refraction of sunlight by the atmosphere, there is actually daylight even when the sun is slightly below the horizon. The period when it is still somewhat light even though the sun is below the horizon is called twilight.
Read more about Day Length: Description, Alternate Definition, Historical Variation of Day Length Because of Tidal Acceleration
Famous quotes containing the words day and/or length:
“O Sword,
you are the younger brother, the latter-born,
your Triumph, however exultant,
must one day be over,
in the beginning
was the Word.”
—Hilda Doolittle (1886–1961)
“At length I met a reverend good old man,”
—George Herbert (1593–1633)