A bioplastic that protects against UV radiation

Researchers at the University of Oulu's Research Unit of Sustainable Chemistry have developed a new synthetic bioplastic that, unlike traditional carbon-based plastics or other bioplastics, provides protection from the sun's ...

'Flapping wings' powered by the Sun

In ancient Greek mythology, Icarus' wax wings melted when he dared to fly too close to the sun. Now, researchers reporting in ACS Applied Materials & Interfaces have made artificial wings that are actually powered by the ...

Mystery at Mars pole explained

In 1966, two Caltech scientists were ruminating on the implications of the thin carbon dioxide (CO2) Martian atmosphere first revealed by Mariner IV, a NASA fly-by spacecraft built and flown by JPL. They theorized that Mars, ...

Researchers find a way to harness the entire spectrum of sunlight

Scientists for the first time have developed a single molecule that can absorb sunlight efficiently and also act as a catalyst to transform solar energy into hydrogen, a clean alternative to fuel for things like gas-powered ...

Image: Thermal enclosure for Orion

The Orion spacecraft with European Service Module at NASA's Plum Brook Station. The first Orion will fly farther from Earth on the Artemis I mission than any human-rated vehicle has ever flown before—but first it will undergo ...

Sunlight degrades polystyrene faster than expected

A study published by researchers at Woods Hole Oceanographic Institution (WHOI) shows that polystyrene, one of the world's most ubiquitous plastics, may degrade in decades or centuries when exposed to sunlight, rather than ...

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Sunlight

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.

This text uses material from Wikipedia, licensed under CC BY-SA