How to use a sextant

Interested in learning Celestial Navigation online? Northeast Maritime Online - NEMO°'s Oceans/Celestial Navigation (500 to 1600 GRT) course covers all topics required for an Oceans Endorsement, including celestial terms, time zones, the sextant, sunrise/sunset, sun line and running fix, compass error and more! This online course features the HALO° Sextant Simulator, an interactive web tool that allows students to learn how to operate a nautical sextant. Get hands-on practice and trainning all f

Sextant - Alchetron, The Free Social Encyclopedia

The History of Navigation – Part 2 Astrolabe • Octant • Sextant Long before GPS, sailors crossed oceans using science and the sky. 🔹 Astrolabe Originated around 200 BCE and later adapted for ocean travel in the 1400s–1500s. Sailors used it to measure the height of the sun or stars above the horizon to determine latitude. 🔹 Octant Invented in the 1730s, the octant used mirrors to measure angles, allowing sailors to see the sun and horizon at the same time — far more accurate on a moving ship. �