Time and Celestial Navigation  It may not be readily apparent
why the date would matter while doing celestial navigation, or
calculating your position via the stars and sun. We readily talk
about the date and time, but the date is really no different
from the time – the date is, in fact, a measure of time. And
time plays a major role in celestial navigation.  Because the
earth rotates on its axis and revolves around the sun, the exact
time (which includes the date and hour of day) is necessary to
understanding the locations and movements of the sun, stars, and
planets and using them to determine your location on the earth.
The revolution of the earth around the sun comes into play and
causes what is known as the sun’s right ascension to change
throughout the year. In a practical sense, if you watched the
sun rise every day over the course of a year, it would rise in a
slightly different spot each morning and eventually return to
its original position after a full year.  Time differences play
a direct factor i