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    Re:Moonrise-over-Connecticut
    From: Bill Ritchie
    Date: 2021 Nov 5, 15:42 -0700

    Peter, 


    I don't think there is any query that ICE calculates the positions for the body centers. It is for which limb (or center) the refraction correction is calculated. 

     

      Object       GHA        Dec            Hc           Zn          Refr    SD     PA     Sum
     SUN        359 59.3   s16 07.3   +73 52.7   180.0        -.3   16.2      .0      15.9

     

    In the above example you quote, the SD correction (applied to Hs) of +16.2 must be for a lower limb sight. Surely, therefore, the authors would have used the refraction for that same limb? The last definition that you quote (below) is consistent with this.

     

    "If Sum is subtracted from Hc, the apparent altitude (that comparable to observation) of the lower limb of the object is obtained." 

     

    Bill Ritchie.

       
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