Daylight

Daylight is the combination of all direct and indirect sunlight present during the daytime, made up of direct sunlight traveling straight from the Sun, diffuse sky radiation scattered by the atmosphere, and sunlight reflected off features such as buildings and landforms; moonlight, though technically reflected sunlight, and light scattered by other astronomical objects are both excluded from the definition. Daylight is present whenever the Sun is above the local horizon, which is true for slightly more than half of the surface of the Earth at any moment, and the refraction of the atmosphere lets some light reach the ground even when the Sun has technically dipped just below the horizon. Its intensity varies enormously, from around 120,000 lux under a bright midday sun, bright enough to cause discomfort, to less than 5 lux under thick storm clouds with the Sun near the horizon, with extreme drops possible during a solar eclipse or when volcanic ash or heavy smoke fills the atmosphere.