Astrolabe Catalogue


Small image of astrolabe rete separated from astrolabe. Click to enlarge.
Date 1221/2 (A.H. 618)
Maker Muḥammad ibn Abī Bakr
Place Iṣfahān
Material Brass
Inventory no. 48213
Acquisition Presented by Lewis Evans in 1924
The rete is of the indicator-line (quatrefoil) type. There is a single rotation knob and two sighting vanes on the front of this rete. A single quatrefoil decorates the center of the ecliptic..There are three zoomorphic star pointers on this rete. The first is the typical bird (falcon ?) that indicate the star Vega. The second is another bird, this time depicted as if in a dive, which points to the star al-Tayir. The third is a horse that points to the star Mankib.The zodiac on the rete is labelled: الحمل , الثور , الجوزا , السرطان , الاسد , السنبله , الميزان , العقرب , القوس , الجدي , الدلو , الحوت


There are 0 stars on the rete marked with dagger pointers. Unless otherwise indicated the star name, mediation and declination are as marked/measured on the rete.
Click on the star name or modern star name to search for other astrolabes with the same star.
Star name
(on instrument)
Modern star
(if known)
Mediation Declination Pointer

Pin & Wedge

The rete is attached using a pin & wedge. The pin is in fact an axle that rotates with the rete to drive the gears. These, in turn, cause the phase of the moon diagram and the solar-lunar diagram to change accordingly. It looks to be a replacement..
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