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Re: Error in Nautical Almanac Polaris SHA Feb-June?
From: Bill Noyce
Date: 2004 Apr 19, 08:57 -0400
From: Bill Noyce
Date: 2004 Apr 19, 08:57 -0400
The biggest effect in changing the SHA for a star is annual aberration,
which moves the star's apparent position in an ellipse about 0.6' long.
For most stars, that translates to a change in SHA of about 0.6' from
one extreme to the other. Polaris is special because a small "distance"
displacement, divided by cos(declination), becomes a large displacement
in SHA. No other navigational star has nearly as small a cos(d).
-- Bill
