List Of Selected Stars For Navigation
Fifty-eight selected navigational stars are given a special status in the field of celestial navigation. Of the approximately 6,000 stars visible to the naked eye under optimal conditions, the selected stars are among the brightest and span thirty-eight constellations of the celestial sphere from the declination of 70° south to 89° north. Many of the selected stars were named in antiquity by the ancient Arabs, Greeks, Romans, and Babylonians.
The star Polaris, often called the "North Star", is treated specially due to its proximity to the north celestial pole. When navigating in the northern hemisphere, special techniques can be used with Polaris to determine latitude or gyrocompass error. The other 57 selected stars have daily positions given in nautical almanacs, aiding the navigator in efficiently performing observations on them. A second group of 115 "tabulated stars" can also be used for celestial navigation, but are often less familiar to the navigator and require extra calculations.
For purposes of identification, the positions of navigational stars — expressed as declination and sidereal hour angle — are often rounded to the nearest degree. In addition to tables, star charts provide an aid to the navigator in identifying the navigational stars, showing constellations, relative positions, and brightness.
Read more about List Of Selected Stars For Navigation: Background, Table, Star Charts, Footnotes
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