Icarus can fly high and save on wax too

"Don't fly too close to the sun," said Daedalus to Icarus. Flying too high would melt the wax in his wings, while going too low would cause the sea's moisture to create drag.

Space mission tests NREL perovskite solar cells

On a clear night, Kaitlyn VanSant will be able to watch her work whiz by. Knowing the success of her project, however, will have to wait until her tiny, temporary addition to the International Space Station returns to Earth.

Sunlight drives leaf mass area based on spectral composition

Plant leaves is the main organ that converts inorganic carbon into organic carbon. Leaf mass area (the leaf mass per unit area, LMA) characterizes the morphological, physiological and biochemical functions of the leaves, ...

Simulating 195 million years of global climate in the Mesozoic

The Mesozoic, which stretched from about 252 million to 66 million years ago, was a pivotal period in Earth's history. In addition to being the age of the dinosaurs, it was when the supercontinent Pangaea began to separate ...

A history of African dust

In a recently published paper, a research team, led by University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science Professor Emeritus Joseph M. Prospero, chronicles the history of African dust transport, ...

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Sunlight, in the broad sense, is the total spectrum of the electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the atmosphere, and the solar radiation is obvious as daylight when the Sun is above the horizon. Near the poles in summer, the days are longer and the nights are shorter or non-existent. In the winter at the poles the nights are longer and for some periods of time, sunlight may not occur at all. When the direct radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and heat. Radiant heat directly produced by the radiation of the sun is different from the increase in atmospheric temperature due to the radiative heating of the atmosphere by the sun's radiation. Sunlight may be recorded using a sunshine recorder, pyranometer or pyrheliometer. Sunlight takes about 8.3 minutes to reach the Earth. The World Meteorological Organization defines sunshine as direct irradiance from the Sun measured on the ground of at least 120 watts per square metre.

Direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux, which includes infrared, visible, and ultra-violet light. Bright sunlight provides luminance of approximately 100,000 candela per square meter at the Earth's surface.

Sunlight is a key factor in photosynthesis, a process crucially important for life on Earth.

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