Rojas' Astrolabe

The astrolabe is an astronomical calculating device used from ancient times into the eighteenth century.

Handcrafted in brass. Beautifully made working reproduction Rojas astrolabe. The astrolabe reached the peak of its popularity in the 16th century. The Spanish astronomer and mathematician Juan de Rojas presented to the European public the Orthographic Projection (1550). This projection was successfully applied in a new type of astrolabe that offered remarkable advantages over its predecessors because it could be used in any Northern latitude.

Measuring the height of a star using the back of the instrument, and knowing the latitude, one could find the time of night and the position of other stars.

The openwork piece on the front, called the rete, is a star map of the northern sky. Pointers on the rete correspond to stars; the outermost circle is the Tropic of Capricorn, and the circle that is off-center represents the zodiac, the apparent annual motion of the sun. Engraved plates that fit below the rete have scales of altitude and azimuth (arc of the horizon) for specific latitudes. 

This beautiful instrument comes complete with wooden base and booklets on use and historical context. The wooden base is ideal for placement of a commemorative plaque in recognition of achievement or an event.

Max Height: 9.65"

Diameter: 7.78"

Thickness:0.28"