Scientists have developed a white paint that cools below the temperature of its ambient surroundings even under direct sunlight. Their research, published October 21 in the journal Cell Reports Physical Science, demonstrates ...
Condensed Matter
Oct 21, 2020
0
80
At least twice in Earth's history, nearly the entire planet was encased in a sheet of snow and ice. These dramatic "Snowball Earth" events occurred in quick succession, somewhere around 700 million years ago, and evidence ...
Earth Sciences
Jul 28, 2020
16
2881
Rice University researchers have created an efficient, low-cost device that splits water to produce hydrogen fuel.
Nanophysics
May 04, 2020
9
5772
A protein called phytochrome B, which can sense light and temperature, triggers plant growth and controls flowering time. How it does so is not fully understood.
Plants & Animals
Apr 04, 2020
3
392
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 ...
Polymers
Feb 21, 2020
0
11
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 ...
Materials Science
Feb 19, 2020
0
205
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, ...
Astronomy
Jan 29, 2020
10
2348
Small fish use light for active sensing to detect potential predators. The yellow black-faced triplefin (Tripterygion delaisi) can reflect downwelling sunlight sideways with its iris, illuminating its immediate surroundings. ...
Plants & Animals
Jan 22, 2020
0
41
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 ...
Materials Science
Jan 21, 2020
15
7995
Chemists at Nanyang Technological University, Singapore (NTU Singapore) have discovered a method that could turn plastic waste into valuable chemicals by using sunlight.
Analytical Chemistry
Dec 11, 2019
0
104
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
