When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  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. Fraunhofer lines - Wikipedia

    en.wikipedia.org/wiki/Fraunhofer_lines

    The Fraunhofer lines are typical spectral absorption lines. Absorption lines are narrow regions of decreased intensity in a spectrum, which are the result of photons being absorbed as light passes from the source to the detector. In the Sun, Fraunhofer lines are a result of gas in the Sun's atmosphere and outer photosphere. These regions have ...

  4. 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.

  5. Chromosphere - Wikipedia

    en.wikipedia.org/wiki/Chromosphere

    The red color of the chromosphere could be seen during the solar eclipse of August 11, 1999.. The density of the Sun's chromosphere decreases exponentially with distance from the center of the Sun by a factor of roughly 10 million, from about 2 × 10 −4 kg/m 3 at the chromosphere's inner boundary to under 1.6 × 10 −11 kg/m 3 at the outer boundary. [7]

  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. 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.

  8. Photosphere - Wikipedia

    en.wikipedia.org/wiki/Photosphere

    The Sun is composed primarily of the chemical elements hydrogen and helium; they account for 74.9% and 23.8%, respectively, of the mass of the Sun in the photosphere.All heavier elements, colloquially called metals in stellar astronomy, account for less than 2% of the mass, with oxygen (roughly 1% of the Sun's mass), carbon (0.3%), neon (0.2%), and iron (0.2%) being the most abundant.

  9. 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 .