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Nautical Almanac
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About the Nautical Almanac
1.We offer a completely new Nautical Almanac.
2.It offers unprecedented ease of calculation and fewer corrections.
3.In navigation, time should not be wasted on calculations.
With the Nautical Almanac, you can get the declination and hour angle without having to refer to other pages.
Outline of this book
1.Each page summarizes different numbers for one day.
2.Time is shown in Universal Time (U.T.C.). In this manual it is expressed as "U".
3.The values in the table are accurate to the last digit, although the E values are written down to 1s and d to 0'.1.
4.The map for the index map of sunrise and sunset times by port is based on "Craft MAP(http://www.craftmap.box-i.net/)".
About Astronomical Position Calculations
1. The coordinates of celestial bodies are calculated assuming that ΔT (TT - UTC) will be 69.184 seconds in 2024. Barycentric Dynamical Time is used to calculate the coordinates of the planets, the Moon, and the Sun. It contains a periodic term relative to Terrestrial Time, with a maximum value average difference of about 0.00166 seconds.
2. The calculation of fixed stars includes proper motion, precession, nutation, annual parallax and annual aberration, and adopts the latest 2006 year theory.
3.By designing a new original modified Julian day (always no more than 32 days), we were able to maximize the accuracy of time, resulting in an accurate representation of milliseconds of time, such as during the Barycentric Dynamical Time, and improved accuracy in astronomical calculations.
4. To calculate the position of celestial objects, the delay in the arrival of light due to the gravitational fields of planets, the Sun, etc., and the bending of light, which are effects of general relativity, are calculated.
For all celestial bodies, it calculates the effects of the gravitational fields of the Sun, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, and the Moon.
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