Persian Planispheric Astrolabe
date: label: date made
content: ca 1715
notes: label: Description
content: This astrolabe was made in the Persian city of Isfahan in about 1715. Isfahan is now in Iran. The object includes a body with throne, a handle that holds a ring for suspending the device, and five plates. One side of one plate has quarter horizons for every three degrees of latitude between twelve degrees and sixty-six degrees. The remaining faces of the plates show a stereographic projection of circles on the celestial sphere for latitudes from twenty-nine degrees to forty degrees. The astrolabe also has a rete or star map, an alidade on the back for sighting stars, a pin that passes through the center, and a wedge that holds the pin in place.
label: Description
content: The upper left quadrant of the back of the astrolabe contains a grid of lines. Horizontal lines represents sines of angles, vertical ones cosines. The rectangular box below the center of the back includes a scales of tangents and cotangents of angles.
label: Description
content: For a detailed description of the instrument, see Gibbs and Saliba.
label: Description
content: The maker, ‘Abd al-A’imma, is well known in the history of Persian astrolabe making, although little biographical information survives. The Smithsonian acquired the instrument from the collection of Samuel V. Hoffman in 1959. It is number CCA40 on the international computerized checklist of astrolabes.
label: Description
content: Compare 333589, 336114, and 316761 which are all by the same maker.
label: Description
content: References:
label: Description
content: For a detailed description of this object, see Sharon Gibbs with George Saliba, <a href="https://repository.si.edu/handle/10088/2444"><I>Planispheric Astrolabes from the National Museum of American History</I></a>, Washington, D.C.: Smithsonian Institution Press, 1984, pp. 74-77. The object is referred to in the catalog as CCA No. 40.
label: Description
content: Another astrolabe associated with the maker is described on
label: Description
content: Astrolabe Catalog of the Oxford Museum of the History of Science, at www.mhs.ox.ac.uk, accessed March 2, 2016.
label: Location
content: Currently not on view
place: label: place made
content: Iran: Eşfahān
topic: label: Subject
content: Mathematics
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Trigonometry
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content: Science & Mathematics
creditLine: label: Credit Line
content: Gift of International Business Machines Corporation
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MA.316761
label: catalog number
content: 316761
label: accession number
content: 215454
objectType: label: Object Name
content: astrolabe
physicalDescription: label: Physical Description
content: brass (overall material)
label: Measurements
content: overall: 3.2 cm x 9.35 cm x 14.9 cm; 1 1/4 in x 3 11/16 in x 5 7/8 in