![]() ![]() It solves this problem ensuring precision of 0,1 arcminute. Sometimes the stars are really hard to find ! T he approximation of the altitude to be set on the sextant can reach five degrees. Nowit can happen that the observer in latitude 40° North has to use the plate for 45° or 35°. The number of the plates (8) is insufficient t he interval of latitude between two plates should be reduced from 10 degrees to 5 degrees. Model 2102-D is the most important star-finder (two main plastic plates - eight plates for latitude North/South : 5°, 15°, 25°, 35°, 45°, 55°, 65°, 75°, 85° - size 12” diameter ). Seamen used various traditional star-finders and spheroscopes in the past nowadays few types of this tool are produced. To do that the altitude set on the sextant (Dead Reckoning Altitude) must have a maximum approximation of one degree. At the beginning of the nautical twilight, the stars cannot be seen by the naked eye but only with the telescope of the sextant. It's fundamental to sight the celestial bodies with a clear horizon. ![]() It allows to identify the brightest stars and to predict the position in the sky of the nautical stars not yet visible. Please check the links below.Stars identifier (marine stars searcher) - Day and night sky (skymap) in an "excel" planisphere (.xls/.xlbs) with animationĪn important manual tool for planning stars and Sun sights ! And diary of astronomical events for a month. We have also given some information stars and constellation associated with each month. Click on the map to Enlarge, save and print. You may, of course print these on a black and white printer. You can get back the text using white or green light. You may print these maps on a colour printer and when use with red touch light the text will nearly disappear and only the stars will be seen. The first set of maps are coloured maps and maps in Duo colour where the text is given red in colour. These stars form what are called asterism which is a group of stars not part of standard list of 88 constellations recognized by the International Astronomical Union but popularized by amateur astronomers. At times some stars are joined with broken lines. Most constellations are shown by joining straight lines. That is brighter stars are marked with bigger dots. The stars are shown with dots in proportion to their brightness or magnitudes. In this projection system the objects closer to the periphery, in this case the constellations closer to horizon would look slightly bigger than those close to the zenith. The maps are drawn using stereographic projection ( see wiki link), that preserves the shape but distorts the size. That is the angular diameter of the horizon circle is 220 deg. The maps shows slightly more sky than that will be visible from this station. +23deg 11′), at 21:00 hours Indian Standard Time (IST). The star map given here are drawn for central station of India (Long 82.5, Lat. These maps can be used anywhere in India at about 21:00 hrs on the 15th of the given month. Given below are two sets of all sky star maps. No member of this committee subscribes to astrology.) We would also talk about positions of planets (grahas) in different constellation which is for the purpose of where to look for those. We have tried to give the Indian names of the stars and constellations (like Nakshtras) for the purpose to remind the reader of this rich tradition. (Disclaimer: India has a great astronomical tradition.
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