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Ahad radius - where the Sun loses its supremacy

  1. Mar 2, 2005 #1
    This is relevant to solar astronomy, defining the edge of Sol's supremacy as the overwhelming provider of all light and heat to our Solar System -

    On any interstellar journey going outward from Earth, one eventually reaches a point where the total amount of light received from our Sun is exactly matched by the total amount of flux coming from all cosmic sources external to our Solar System. The heliocentric distance of that boundary is dubbed the "Ahad radius", and exists at
    the edge of "Ahad's sphere of solar illuminance", some 11,500 astronomical units (roughly a trillion [10^12] miles) from Earth.

    On first definition of this heliocentric boundary, Abdul Ahad wrote:-

    "Beyond the outer edges of this theoretical sphere, the feeble currents of light coming from its core (i.e. our own distant Sun) will cease to make any noticeable ripples in the calm waters of the surrounding cosmic ocean..." - July, 2004.

    In the context of space exploration, no man-made spacecraft has yet escaped beyond the "Ahad sphere"; Voyager 1 is leading the charge and will reach the AR in just over 3,000 years from now. Voyager 2, Pioneers 10 and 11 will all follow after that.

    From the paper:

    http://www.astroscience.org/abdul-ahad/firstarktoalphacentauri/interstellar.htm [Broken]
    Last edited by a moderator: May 1, 2017
  2. jcsd
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