The Northern Star Chart of Navigational Astronomy 7.5 Cm Round Badge

The Northern Star Chart of Navigational Astronomy 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 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.