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Young Curly Brunette Girl Undresses A Black Bikini Bra In The Sand On A Sunny Day
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The World Meteorological Organization uses the term "sunshine duration" to mean the cumulative time during which an area receives direct irradiance from the Sun of at least 120 watts per square meter.
Sunlight may be recorded using a sunshine recorder, pyranometer or pyrheliometer. Sunlight takes about 8.3 minutes to reach the Earth.
On average, it takes energy between 10,000 and 170,000 years to leave the sun's interior and then be emitted from the surface as light.
Direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux. Bright sunlight provides illuminance of approximately 100,000 lux or lumens per square meter at the Earth's surface.
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