Exhibition Label - 'The Moon'; National Maritime Museum, 19 July 2019 - 5 January 2020
Astrolabe with geared calendar
by Muhammad ibn Abi Bakr, 1221-2 CE
Invented in Ancient Greece and later developed by Islamic scholars, the astrolabe is a complex astronomical calculator. This version has been taken apart to show its unusual lunar features. The front section (shown on the left) has a cut-out plate that is rotated to predict the rising and setting times of bright stars. The right-hand section has a Moon phase indicator controlled by a concealed geared movement, visible in the mirror behind. Muslim astronomers use the first sighting of the Crescent Moon as the defining moment of each new Islamic month.
LOA2433: History of Science Museum, University of Oxford, Inv. 48213
Other narratives:
- Astronomical mechanisms
- Geared astrolabe inscription
- Inventory no. 48213 - Former Display Label
- Relationship between astrolabe and calendar
- Oldest in the world
- Special Exhibition Label: 'Al-Mizan: Sciences and Arts in the Islamic World' (26/10/2010 - 20/03/2011)