Description
The Sight Reduction Tables for Marine Navigation (Pub 229) is published in six volumes, each of which contains two-eight degree zones of latitude with one-degree overlap between volumes. They are designed to facilitate the practice of celestial navigation at sea. The tables are primarily used with the intercept method of sight reduction by entering arguments of latitude, declination and local hour angle and obtaining tabulated altitudes and azimuth angles. The tables are prepared and published by NGA (NIMA) on an as needed basis.
Sight Reduction Tables are used in celestial navigation to "reduce" (analyze) the "sights" (data obtained from a sextant at known times) in order to find your latitude and longitude. There are several styles of these tables, but they all do exactly the same thing: You tell the tables a location on earth and a location of a celestial body (the point on earth where the body would be directly overhead), and the tables tell you the angular height of that body above the horizon (viewed from the location you provided) and they tell you the true bearing to the body along the horizon. In the jargon of cel nav, you enter the tables with Assumed Latitude (a-Lat), declination (dec), and Local Hour Angle (LHA) and the tables tell you the calculated altitude (Hc) and azimuth (Zn) of the body. The various styles of tables differ only in how they are laid out and the final precision of the answers.
Specifications
Rebates
There are currently no rebates available for this item
