Namely, before radio navigation, satellite or radar. Did we move right from manual celestial navigation right to radar to radio (like loran) to GPS or was there something else after celestial navigation that I am missing|||Yes, celestial navigation was important, but so was having a stable and accurate clock. People tend to overlook that aspect of navigation. This really had to do with knowing longitude.
Between 1800 and 1850 (earlier in British and French navigation practice, later in American, Russian, and other maritime countries), affordable, reliable marine chronometers became available, replacing the method of lunars as soon as they reached the market in large numbers. It became possible to buy two or more relatively inexpensive chronometers, serving as checks on each other, rather than acquiring a single (and expensive) sextant of sufficient quality for lunar distance navigation.
The development of wireless telegraph time signals in the early 20th century, used in combination with marine chronometers, put a final end to the use of lunar distance tables.|||Celestial Navigation using a sextant and a very accurate time piece was used even after Radio Aids to Navigation came on line.
The first radio aid were just beacons where you use a direction finder to point to the transmitter, then Loran. Even with Loran the sextant was still used. Even today the sextant is still used to some extent as a back up in case of failure of the GPS.
Nuclear Submarine have a special periscope with a sextant built in and controlled by a computer and it is just as accurate as GPS.|||Position fixing was done via celestial Navigation (using a sextant for accuracy) and an accurate clock.
The sextant told you your latitude by measuring the angle of celestial object above the horizon and comparing to a chart. The clock told you your longitude by comparing the clock time of home port with current celestial time of the sun/moon or stars.
Position estimating was done through dead reckoning. From your last fixed position and knowing your speed and heading you can estimate your current position if celestial objects are not available for a fix. A good navigator can take into account known currents and wind that make the true heading a degree or 2 different than compass heading. Also dead reckoning requires charts of compass deviation as magnetic north is not exactly aligned with true north and it drifts around.
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