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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: ex-meridian sights
From: Steven Wepster
Date: 2001 Feb 12, 8:13 AM
From: Steven Wepster
Date: 2001 Feb 12, 8:13 AM
Your quote doesn't say that Table 24 gives the change per minute; it says that it gives the change _in one minute from the meridian_ . The change in altitude is not linear so that's why Table 25 was not calculated using Correction = a X t/60. Apparently a second-order extrapolation (ie, a formula involving the square of t) is considered sufficient (I didn't look int that in detail). It is quite natural that the correction formula does not contain a first order term (a factor times t) because that would spoil the symmetrical change in altitude before and after transit. Regards, _Steven Wepster.
