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6: Limb Darkening

  • Page ID
    6684
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    Limb darkening is an optical effect seen in stars (including the Sun), where the center part of the disk appears brighter than the edge or limb of the image.

    • 6.1: Introduction. The Empirical Limb-darkening
      This page discusses limb darkening in the Sun, characterized by decreasing brightness at the edges, especially in blue wavelengths. It explains the mathematical representation through intensity equations with a limb darkening coefficient, \(u\), and attributes the effect to light traveling through varying solar atmospheric depths.
    • 6.2: Simple Models of the Atmosphere to Explain Limb Darkening
      This page examines models of limb darkening in stellar atmospheres, particularly for the Sun, highlighting discrepancies between observational data and existing models. It explores a mathematical approach using varying source functions to better understand limb darkening.

    Thumbnail: A filtered image of the Sun in visible light, showing the limb-darkening effect as a dimmer luminosity towards the edge or limb of the solar disk. The image was taken during the 2012 transit of Venus (seen here as the dark spot at the upper right). (CC BY 2.5; Brocken Inaglory).


    This page titled 6: Limb Darkening is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Jeremy Tatum via source content that was edited to the style and standards of the LibreTexts platform.