Document Type


Publication Date

Fall 2010


Ancient societies had a universal curiosity about the heavens. This is no coincidence; astronomic cycles are highly important for determining expected daylight and nightlight, time of day, length of the season, and time of year, factors that affected everything from hunting habits to crop cycles. As a general rule, the knowledge to predict the course of the heavens was vitally important for daily life.

Astrolabes are a tool that collapsed observed heavenly rotations into a small, easy-to-use model, allowing a learned user to predict the state of the heavens at specific times. This one task allows the user to solve a wide array of astronomical problems, such as telling the current time or determining when the sun will set. In addition, the astrolabe also gives the user a framework for parsing the heavenly rotation into understandable, predicable phenomena, giving the illusion of power over the heavens.

The astrolabe was a portable celestial model and had a strong general utility, suitable for a broad range of problems involving the heavens. This utility made it easily adapted by various medieval cultures, but once adapted, astrolabe technology became specialized for the specific tasks valued by each culture. However, astrolabe adaptation was not limited to astronomic functionality, but to symbolic functionality as well. This adaptation is consistent with the theory of interpretive flexibility, where users determine how a technology specializes until the technology is replaced by an even more specialized device. Persian, European, and Mariner’s astrolabes all show this progression, either in the functional or symbolic aspects of the astrolabe.