What Is a Sextant?
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A sextant is a navigation instrument used to measure the angle between a celestial object and the horizon.
It became an essential tool in marine navigation because it allowed navigators to estimate position using the Sun, stars, and other celestial bodies.
What is this page about?
This page explains what a sextant is, what it was used for, and why it remains interesting and important even in the age of GPS.
What a Sextant Does
A sextant helps a navigator measure angles very precisely. Those measurements can then be used together with time and reference tables to help determine position.
Why It Mattered
- It supported navigation before electronic systems existed
- It allowed navigators to estimate latitude and position
- It was especially important at sea
- It remains a classic example of practical navigation skill
Why It Still Matters Today
Even though GPS is now common, the sextant is still valuable as a teaching tool, a backup concept, and a reminder that navigation once depended entirely on observation and skill.
Keep It Simple
You do not need advanced mathematics to appreciate what a sextant is. At its core, it is a precise instrument for measuring the angle between the horizon and an object in the sky.