Astrolabes were the medieval version of a GPS. Although still fashioned today in various manifestations, the most famous versions were those created by Muslim scientists living in the Medieval Middle East. If you’ve ever seen one, this photo from the Islamic world circa 1480 CE might look different: usually astrolabes were two-dimensional celestial spheres. I chose this one because it illustrates in three dimensions the sort of information an astrolabe could impart: the time of day and year, the position of celestial objects in the sky, and the latitude and longitude of the star gazer, for instance.
