High-frequency light is useful. The higher the frequency of light, the shorter its wavelength – and the shorter the wavelength, the smaller the objects and details the light can be used to see. So ...

When researchers reviewed footage of flying insects, they saw that the bugs tilted their backs toward the source of artificial light. Imperial College London Flip on a porch light on a summer evening ...

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Light normally spreads out rapidly in all directions; a laser coheres the light in a narrow beam. The key to producing this ...

Cities are artificially lit to allow humans to make use of the night. This light pollution means that stars are often barely visible in urban skies. But reduced stargazing is not the only impact of ...

The outdoor world is growing more and more illuminated with artificial light. More than 80 per cent of the world's population lives under a “lit sky”, and in Europe and North America the figure is ...