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  2. Blacklight - Wikipedia

    en.wikipedia.org/wiki/Blacklight

    A blacklight, also called a UV-A light, Wood's lamp, or ultraviolet light, is a lamp that emits long-wave ultraviolet light and very little visible light. [ 1 ] [ 2 ] [ 3 ] One type of lamp has a violet filter material, either on the bulb or in a separate glass filter in the lamp housing, which blocks most visible light and allows through UV ...

  3. Sun - Wikipedia

    en.wikipedia.org/wiki/Sun

    The Sun is the star at the center of the Solar System.It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light and infrared radiation with 10% at ultraviolet energies.

  4. The Sun is not yellow; rather, it emits light across the full spectrum of visible colors, and this combined light appears white when outside of Earth's atmosphere. Earth's atmosphere scatters shorter wavelengths of light, particularly blues and violets, more than longer wavelengths like reds and yellows, and this scattering is why the Sun ...

  5. Solar granule - Wikipedia

    en.wikipedia.org/wiki/Solar_granule

    In solar physics and observation, granules are convection cells in the Sun's photosphere. They are caused by currents of plasma in the Sun's convective zone , directly below the photosphere. The grainy appearance of the photosphere is produced by the tops of these convective cells; this pattern is referred to as granulation .

  6. Black-body radiation - Wikipedia

    en.wikipedia.org/wiki/Black-body_radiation

    When the body is black, the absorption is obvious: the amount of light absorbed is all the light that hits the surface. For a black body much bigger than the wavelength, the light energy absorbed at any wavelength λ per unit time is strictly proportional to the blackbody curve. This means that the blackbody curve is the amount of light energy ...

  7. Solar phenomena - Wikipedia

    en.wikipedia.org/wiki/Solar_phenomena

    A solar flare is a sudden flash of brightness observed over the Sun's surface or the solar limb, which is interpreted as an energy release of up to 6 × 10 25 joules (about a sixth of the total Sun's energy output each second or 160 billion megatons of TNT equivalent, over 25,000 times more energy than released from the impact of Comet ...

  8. Astronomical spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Astronomical_spectroscopy

    The Star-Spectroscope of the Lick Observatory in 1898. Designed by James Keeler and constructed by John Brashear.. Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light, ultraviolet, X-ray, infrared and radio waves that radiate from stars and other celestial objects.

  9. Crepuscular rays - Wikipedia

    en.wikipedia.org/wiki/Crepuscular_rays

    Crepuscular rays are noticeable when the contrast between light and dark is most obvious. Crepuscular comes from the Latin word crepusculum, meaning "twilight". [2] Crepuscular rays usually appear orange because the path through the atmosphere at dawn and dusk passes through up to 40 times as much air as rays from a high Sun at noon.