Celestial Bodies 
The celestial bodies: moon, sun, planets, and stars, are 
all old friends of the mariner. Like old friends they have 
many things to tell us, tales of magnitudes and measures 
transcending our ability to understand and appreciate, and 
other stories, too, which give us perspective, or at least some 
inkling of our place in the universe. 
THEIR MOTIONS 
The astronomical bodies which we see execute a regular 
motion across the sky during the course of a single night, and 
a similar though longer period motion over the course of the 
year. These two principal motions of the celestial bodies, the 
daily and the yearly, are to be considered as apparent rather 
than real because they are produced by the daily rotation of 
the earth about its axis and its yearly revolution about the 
sun in its orbit. Superimposed upon these two chief motions 
are the peculiar motions of the celestial bodies themselves, 
the most outstanding of which is that of the moon which 
moves among the stars a distance equal to its own diameter 
each hour. The planets also have motions of their own super- 
imposed upon the overall daily and yearly apparent motions 
previously mentioned. Although they are fairly complicated 
motions they are all capable of being calculated mathemati- 
cally and the positions of the planets will be found tabulated 
for each day of the year in The American Ephemeris and 
Nautical Almanac or the British Nautical Almanac. All of 
these tables are the result of long and tedious computations 
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