Navigational Sextants

Finding out the exact place and where one is heading while in unfamiliar territory has always been a challenge. Whether traveling on the high seas, across featureless terrain, people had to be able to navigate accurately if they were to get to their destinations in a reasonable amount of time. On many occasions, the ability to navigate has been the difference between life and death.

Sextants are instruments that are used for navigating and surveying for maps. The user looks through an eyepiece, through which they can see the horizon and the reflection from the sky in the mirrors. If the second mirror on a moving arm is adjusted, the user can make a celestial body, such as a star, the Sun or the Moon appear to rest on the horizon as they look through the eyepiece. An angle in degrees can be read off the sextant and used to calculate lunar distance, longitude and where the ship is located on the Earth.

Sextants are instruments used by mariners to measure the angular distance between two objects (like the sun and the horizon). They are more accurate than astrolabes by having a telescope, mirrors, and a graduated arm. The mirrors allow seeing both objects simultaneously. When the computer crashes or there is no electricity, sailers must rely on this old-fashion instruments to guide them.