astrolabes in islam a model of the universe you can hold in your hand. by dr. harold williams

Astrolabes in Astrolabes in IslamIslam

A model of the universe you can hold in your A model of the universe you can hold in your hand.hand.

By Dr. Harold WilliamsBy Dr. Harold Williamshttp://montgomerycollege.edu/Departments/planethttp://montgomerycollege.edu/Departments/planet

Internet Astrolabe resourcesInternet Astrolabe resources

http://astrolabes.orghttp://astrolabes.org Janus, Jim Morrison, Janus, Jim Morrison, best general source of astrolabe best general source of astrolabe information on the net. The electric information on the net. The electric astrolabe a free download only works on astrolabe a free download only works on Wintel machines. The best laminated in Wintel machines. The best laminated in plastic plainspheric astrolabe.plastic plainspheric astrolabe.

http://www.mathsyear2000.org/museum/flhttp://www.mathsyear2000.org/museum/floor2/gallery4/indastro/index.htmloor2/gallery4/indastro/index.html Keith Powell's Java astrolabe.Keith Powell's Java astrolabe.

Recently made Islamic Recently made Islamic AstrolabeAstrolabe

Dr. Hasan Bilani, University of Dr. Hasan Bilani, University of Aleppo, SyriaAleppo, Syria November 2000November 2000

It is not a reproduction of a specific It is not a reproduction of a specific instrument but is in the style of a instrument but is in the style of a typical, high quality Islamic astrolabe.typical, high quality Islamic astrolabe.

It was designed using AutoCAD and It was designed using AutoCAD and was engraved by chemical milling.was engraved by chemical milling.

It required about two months to It required about two months to manufacture. It is made of brass and is manufacture. It is made of brass and is about eight inches in diameter and 5.5 about eight inches in diameter and 5.5 mm thick and weighs 900 gm. There mm thick and weighs 900 gm. There are 23 stars precessed to the current are 23 stars precessed to the current epoch. There are six plates provided epoch. There are six plates provided but only two can but only two can be but only two can but only two can be held in the mater at a time. The quote held in the mater at a time. The quote from the Koran on the throne (kursi) from the Koran on the throne (kursi) is "…and by the stars (men) guide is "…and by the stars (men) guide themselves".themselves".

ReteRete

MatterMatter

Climate or tympanum, 1Climate or tympanum, 1

Horizons Plate for casting Horizons Plate for casting HoroscopesHoroscopes

Part of the AstrolabePart of the Astrolabe

ReteRete, net in Latin, the , net in Latin, the star map, off axis star map, off axis circle the ecliptic (the circle the ecliptic (the zodiacal signs)zodiacal signs)

Plates (Plates (climateclimate or or tympanumtympanum), ), latitude specific, latitude specific, horizon coordinate horizon coordinate system, altitude and system, altitude and azimuthazimuth

Janus astrolabe Janus astrolabe reterete

Stereographic Projection of ReteStereographic Projection of Rete

For a For a reterete to to represent the represent the Northern hemisphereNorthern hemisphere

North pole, equator, and tropics North pole, equator, and tropics

projectionprojection

Ecliptic projectionEcliptic projection

Rete for 2800BCERete for 2800BCE

Rete for 500BCERete for 500BCE

Rete for 140Rete for 140

Plate (Plate (climate or tympaniumclimate or tympanium)) Altitudes or almucantersAltitudes or almucanters Twilight Arcs, -6º Civil, -Twilight Arcs, -6º Civil, -

12º Nautical, -18º 12º Nautical, -18º Astronomical Astronomical

AzimuthsAzimuths North 0º & 360º North 0º & 360º East 90º East 90º South 180º South 180º West 270º West 270º

Altitude ProjectionsAltitude Projections

Lines of equal Azimuth ProjectionLines of equal Azimuth Projection

Hour angle ProjectionsHour angle Projections

Complete Climate ProjectionComplete Climate Projection

Climate for 25 degreesClimate for 25 degrees

Plate for 0 and 90 degreesPlate for 0 and 90 degrees

Plate for ecliptic transformationPlate for ecliptic transformation

Plate for all horizons in 5 degree Plate for all horizons in 5 degree incrementsincrements

Back of astrolabeBack of astrolabe

Highly variableHighly variable But most had But most had

calendar and zodiaccalendar and zodiac & angle measuring & angle measuring

protractorprotractor Notice perihelion and Notice perihelion and

aphelion and center aphelion and center of calendar & zodiacof calendar & zodiac

Janus astrolabe the college editionJanus astrolabe the college edition

Set for July 25 at 10PM at Takoma Park, Latitude 38°58’.

Astrolabe styles in IslamAstrolabe styles in Islam

Persia Persia http://en.wikipedia.org/wiki/Persia http://en.wikipedia.org/wiki/Persia Iran MashriqMashriq http://en.wikipedia.org/wiki/Mashriq http://en.wikipedia.org/wiki/Mashriq

Arabic Middle EastArabic Middle East MaghribMaghrib http://en.wikipedia.org/wiki/Maghreb http://en.wikipedia.org/wiki/Maghreb

North AfricaNorth Africa AndalusiaAndalusia http://en.wikipedia.org/wiki/Andalusia http://en.wikipedia.org/wiki/Andalusia

Moorish Spain Moorish Spain

Astrolabes in Islam referencesAstrolabes in Islam references

Islamic astronomyIslamic astronomy http://en.wikipedia.org/wiki/Islamic_astronomyhttp://en.wikipedia.org/wiki/Islamic_astronomy

Muslim astronomers Muslim astronomers http://en.wikipedia.org/wiki/Muslim_astronomershttp://en.wikipedia.org/wiki/Muslim_astronomers

Some Islamic Astronomers Some Islamic Astronomers

Abd Al-Rahman Al Sufi (Abd Al-Rahman Al Sufi (December 7, December 7, 903 – May 25, 986903 – May 25, 986)) http://en.wikipedia.org/wiki/%27Abd_Al-Rahman_Al_Sufihttp://en.wikipedia.org/wiki/%27Abd_Al-Rahman_Al_Sufi Amazing treatise of 386 chapters Amazing treatise of 386 chapters presenting 1000 uses of the astrolabe presenting 1000 uses of the astrolabe

Astrolabes reaching the WestAstrolabes reaching the West

Gerbert of A’urillac, Gerbert of A’urillac, Gerbert d'Aurillac, Gerbert d'Aurillac, Pope Silvester II, (Pope Silvester II, (caca. . 950950 – May 12, 1003) – May 12, 1003) http://en.wikipedia.org/wiki/Gerbert_of_Aurhttp://en.wikipedia.org/wiki/Gerbert_of_Aurillacillac

astrolabes in islam a model of the universe you can hold in your hand. by dr. harold williams

Documents