Sextant, Navigational Instrument

A sextant is an instrument used to measure the angle between any two visible objects. Its primary use is to determine the angle between a celestial object and the horizon which is known as the object's altitude. Making this measurement is known as sighting the object, shooting the object, or taking a sight and it is an essential part of celestial navigation. The angle, and the time when it was measured, can be used to calculate a position line on a nautical or aeronautical chart. Common uses of the sextant include sighting the sun at solar noon and sighting Polaris at night, to find one's latitude (in northern latitudes). A sextant can also be held horizontally to measure the angle between any two landmarks which allows for calculation of a position on a chart

Restrictions Only for Ireland and United Kingdom

Celestial Measure Navigational Navigators Sextant Sighting

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