Lunch cutlery
Lunch cutlery is a term used in seafaring , especially in nautical science .
In maritime parlance, lunch cutlery is the noon calculation of the ship's location, i.e. determination of the geographical latitude , also known as latitude . This method is based in particular on the aiming (called shooting ) of the sun , the maximum height of the sun (culmination) is measured with the help of a sextant (formerly also quadrant ). Furthermore, the results longitude ( Longitude ) from the deviation of ship time from standard time (time GMT ) by a chronometer appears on board. The ship's time, i.e. the actual local time, cannot be determined by direct time measurement because of the flat course of the sun around the culmination time, but by averaging two equal sun heights measured to the second some time before and after the culmination.
The process dates back to the time of astronomical navigation and was brought to perfection in the 19th century. At the end of the 20th century, it was replaced by electronic methods, especially satellite navigation . Although it has become meaningless in daily practice, it is taught for educational purposes and in the event that modern systems fail.