Sunrise

Sunrise, also called sunup in some American English dialects, is the time at which the first part of the Sun appears above the horizon. Sunrise should not be confused with dawn, which is the (variously defined) point at which the sky begins to lighten, some time before the sun itself appears.

As sunrise and sunset are calculated from the leading and trailing edges of the Sun, and not the center; this slightly increase the duration of "day" relative to "night".

The color of the sky at sunrise is explained by the phenomenon of Rayleigh scattering.