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Re: Finding IC for A-12 bubble sextants
From: Brian Walton
Date: 2021 Oct 8, 18:37 -0700
From: Brian Walton
Date: 2021 Oct 8, 18:37 -0700
"Q" correction in your head.
Polaris sits on Cassiopeia's throne. He is 40 miles closer to Cass than the true N Pole.
If the line Cass-Pol-Dipper is horizontal, Q correction is 0. If Cass is straight up, Pol is 40' too high. If Cass is straight down, Pol is 40' too low.
In between is in between. Use the aviator's 1:60 trick. 15°=30%, 30°=50%, 45°=70%, 60°=80%, etc, as used in crosswind/drift estimation.
All done in the head. Latitude with no tables.
Brian Walton
