Definition
NP 401, the American Pub 229, tabulates calculated altitude and azimuth for whole degrees of latitude, declination and local hour angle, and suits any body to high precision. NP 303, the American Pub 249, is the air series: Volume 1 gives selected stars for a given latitude and hour angle of Aries, while Volumes 2 and 3 handle bodies with declinations up to 29 degrees. Both replace the spherical trigonometry with lookups.
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