It serves as a star chart and physical model of the visible half-dome of the sky. Its various functions also make it an elaborate inclinometer and an analog calculation device capable of working out several …

astrolabe, any of a type of early scientific instrument used for reckoning time and for observational purposes. One widely employed variety, the planispheric astrolabe, enabled astronomers to calculate …

Aug 31, 2023 · The astrolabe was a device used by explorers like Christopher Columbus to help them navigate since with it they could measure the altitude of certain stars and so calculate their latitude.

May 25, 2022 · An astrolabe is an astronomical instrument used since ancient times. It consists of rotating discs and rulers to show the positions of astronomical objects at any given time throughout …

Any instrument used to measure altitudes above the horizon can be called an astrolabe, although there is a major difference between the classic “planispheric astrolabe” and a “mariner’s astrolabe.”

Mar 7, 2025 · An astrolabe is an ancient astronomical instrument used to measure time, track celestial bodies, and aid in navigation. It consists of a circular disk with a rotating star map and an adjustable …

Jul 5, 2012 · Build your own simple astrolabe to determine your latitude, as the ancient sailors did, or use it in conjunction with trigonometry to determine the height of a very tall object!

The astrolabe was used for dozens of purposes, but its foremost use was in measuring celestial altitude, meaning the relative ‘height’ of a star, moon or planet.

Rule Astrolabe made by Georg Hartmann in Nuremberg in 1537, showing a one-sided alidade. Photo by Sage Ross.

The planispheric astrolabe is the most important and versatile instrument made in antiquity for the analogical performance of astronomical computations that would otherwise have been long and …