The principle of the instrument was first implemented around 1731 by John Hadley (1682–1744) and Thomas Godfrey (1704–1749), but it was also found later in the unpublished writings of Isaac Newton (1643–1727). In 1922, it was modified for aeronautical navigation by Portuguese navigator and naval officer Gago Coutinho.
When was the octant invented?
The octant is a navigational instrument that was developed around 1730 almost simultaneously by an English mathematician, John Hadley, and an American glazier, Thomas Godfrey.
What were sextants used for?
The sextant was designed to find longitude by measuring the angular distance between the moon and a nearby star. It was also used on land and to find latitude at sea. A sextant is similar to an octant, but more powerful and precise. The arc extends 60o or more and measures angles of 120o or more.
