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  2. Ultraviolet - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet

    The atmosphere blocks about 77% of the Sun's UV, when the Sun is highest in the sky (at zenith), with absorption increasing at shorter UV wavelengths. At ground level with the sun at zenith, sunlight is 44% visible light, 3% ultraviolet, and the remainder infrared.

  3. Sunlight - Wikipedia

    en.wikipedia.org/wiki/Sunlight

    Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth , sunlight is scattered and filtered through Earth's atmosphere as daylight when the Sun is above the horizon .

  4. Health effects of sunlight exposure - Wikipedia

    en.wikipedia.org/wiki/Health_effects_of_sunlight...

    Effects of UV-radiation at high latitudes, where snow stays on the ground into early summer and the sun then remains at a low position even at its zenith, have been reviewed by Meyer-Rochow. [15] UV map . Exposure to ultraviolet radiation from the sun is a source of vitamin D.

  5. Electromagnetic spectrum - Wikipedia

    en.wikipedia.org/wiki/Electromagnetic_spectrum

    UV, X-rays, and gamma rays are thus collectively called ionizing radiation; exposure to them can damage living tissue. UV can also cause substances to glow with visible light; this is called fluorescence. UV fluorescence is used by forensics to detect any evidence like blood and urine, that is produced by a crime scene.

  6. Ultraviolet index - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet_index

    The ultraviolet index, or UV index, is an international standard measurement of the strength of the sunburn-producing ultraviolet (UV) radiation at a particular place and time. It is primarily used in daily and hourly forecasts aimed at the general public.

  7. Shortwave radiation (optics) - Wikipedia

    en.wikipedia.org/wiki/Shortwave_radiation_(optics)

    UV-C radiation spans from 0.1μm to .28μm, UV-B from 0.28μm to 0.315μm, UV-A from 0.315μm to 0.4μm, the visible spectrum from 0.4μm to 0.7μm, and NIR arguably from 0.7μm to 5.0μm, beyond which the infrared is thermal. [1] Shortwave radiation is distinguished from longwave radiation.

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  9. Full-spectrum light - Wikipedia

    en.wikipedia.org/wiki/Full-spectrum_light

    Full-spectrum light is light that covers the electromagnetic spectrum from infrared to near-ultraviolet, or all wavelengths that are useful to plant or animal life; in particular, sunlight is considered full spectrum, even though the solar spectral distribution reaching Earth changes with time of day, latitude, and atmospheric conditions.