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Nautical Almanac
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About 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 various figures for one day.
2.Time will be 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 number, 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) in 2024 is 69.184 seconds. For the calculation of the coordinates of planets, the moon and the sun, the Barycentric Dynamical Time is used. It contains a periodic term relative to Terrestrial Time, with a maximum value average difference of about 0.00166 seconds.
2. The of the planets, the moon and the sun is very accurate using DE440T of NASA Jet Propulsion Laboratory.
3. The calculation of fixed stars includes proper motion, precession, nutation, annual parallax, and annual aberration, and adopts the latest 2006 year theory.
4.By designing a new original modified Julian day (always no more than 32 days), we were able to maximize the accuracy of the time, resulting in an accurate representation of milliseconds of time, such as during the Barycentric Dynamical Time, and improved accuracy in astronomical calculations.
5. To calculate the position of celestial objects, the arrival delay of light due to the gravitational fields of planets, the sun, etc. and the bending of light are calculated, which are effects of the general theory of relativity.
In the case of planets, we calculate the effects of the gravitational fields of the Sun, Mercury, Venus, Mars, Jupiter, and the Moon.
For fixed stars, we calculate the effects of the gravitational fields of the Sun, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, and the Moon.
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