Celestial Navigation

Einstein is right: Space and Time are a continuum. For me personally, this means that you can actually see time if you are looking to the stars. Some stars you see doesn't even exist anymore. In Celestial Navigation time is distance. Longitude is measured in degrees, the world turns in 24 hours so one second of time is roughly ¼ mile at the equator where we are (almost) now. It is obvious that this also explains the need for a very accurate watch when determining your celestial position.

I will try to explain how this works without being complete or completely correct.
Imagine you see a star 45 degrees above the horizon in a southern direction; the only thing you have to do is to draw an imaginary cone from that star with the point touching the star and the circular base of the cone touching the earth. Angle of the cone between the legs is the same as you see the star above the horizon. Look at another star in an easterly direction, draw this cone too. Now you have two circles crossing each other on the earth at two points. One of these crossings is your position. Very simple. To calculate your accurate position (and to eliminate the wrong one) you need some more mathematics however.

Having a sextant does not mean that you can work with it. Yogi Berra said: "In theory, there should be no difference between theory and practice, but in practice, there is"
And that is why our trainee is practicing with our sextant until he is able to determine a position more accurate than his average dead reckoning position at the time of shooting.