ʿAbd al-Rahman al-Sufi ( fa, عبدالرحمن صوفی; December 7, 903 – May 25, 986) was an

iranian Iranian may refer to: * Iran, a sovereign state * Iranian peoples, the speakers of the Iranian languages. The term Iranic peoples is also used for this term to distinguish the pan ethnic term from Iranian, used for the people of Iran * Iranian lan ...

Robert Harry van Gent.
Biography of al-Sūfī
'. "The Persian astronomer Abū al-Husayn ‘Abd al-Rahmān ibn ‘Umar al-Sūfī was born in Rayy (near Tehrān) on 7 December 903

4 Muharram 291 H 4 (four) is a number, numeral and digit. It is the natural number following 3 and preceding 5. It is the smallest semiprime and composite number, and is considered unlucky in many East Asian cultures. In mathematics Four is the smallest c ...

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either ...

also known as ʿAbd ar-Rahman as-Sufi, ʿAbd al-Rahman Abu al-Husayn, ʿAbdul Rahman Sufi, or ʿAbdurrahman Sufi and, historically, in the

West West or Occident is one of the four cardinal directions or points of the compass. It is the opposite direction from east and is the direction in which the Sun sets on the Earth. Etymology The word "west" is a Germanic word passed into some ...

as Azophi, Azophi Arabus, and Albuhassin. Al-Sufi published his famous '' Book of Fixed Stars'' in 964, which included both textual descriptions and pictures. Al-Biruni reports that his work on the ecliptic was carried out in

Shiraz Shiraz (; fa, شیراز, Širâz ) is the fifth-most-populous city of Iran and the capital of Fars Province, which has been historically known as Pars () and Persis. As of the 2016 national census, the population of the city was 1,565,572 p ...

. He lived at the

Buyid The Buyid dynasty ( fa, آل بویه, Āl-e Būya), also spelled Buwayhid ( ar, البويهية, Al-Buwayhiyyah), was a Shia Iranian dynasty of Daylamite origin, which mainly ruled over Iraq and central and southern Iran from 934 to 1062. Co ...

court in

Isfahan Isfahan ( fa, اصفهان, Esfahân ), from its ancient designation ''Aspadana'' and, later, ''Spahan'' in middle Persian, rendered in English as ''Ispahan'', is a major city in the Greater Isfahan Region, Isfahan Province, Iran. It is lo ...

Biography

ʿAbd al-Rahman al-Sufi was one of the nine famous Muslim astronomers. His name implies that he was a

Sufi Muslim Sufism ( ar, ''aṣ-ṣūfiyya''), also known as Tasawwuf ( ''at-taṣawwuf''), is a mystic body of religious practice, found mainly within Sunni Islam but also within Shia Islam, which is characterized by a focus on Islamic spirituality, ...

. He lived at the court of

Emir Emir (; ar, أمير ' ), sometimes transliterated amir, amier, or ameer, is a word of Arabic origin that can refer to a male monarch, aristocrat, holder of high-ranking military or political office, or other person possessing actual or cer ...

Adud ad-Daula in

Persia Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...

, and worked on translating and expanding Greek astronomical works, especially the ''

Almagest The ''Almagest'' is a 2nd-century Greek-language mathematical and astronomical treatise on the apparent motions of the stars and planetary paths, written by Claudius Ptolemy ( ). One of the most influential scientific texts in history, it can ...

'' of

Ptolemy Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importanc ...

. He contributed several corrections to Ptolemy's

star A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...

list while his

brightness Brightness is an attribute of visual perception in which a source appears to be radiating or reflecting light. In other words, brightness is the perception elicited by the luminance of a visual target. The perception is not linear to luminance, ...

and magnitude estimates frequently deviated from those in Ptolemy's work, with only 55% of Al-Sufi's magnitudes being identical to Ptolemy's. He was a major contributor to the translation into Arabic of the

Hellenistic In Classical antiquity, the Hellenistic period covers the time in Mediterranean history after Classical Greece, between the death of Alexander the Great in 323 BC and the emergence of the Roman Empire, as signified by the Battle of Actium in ...

astronomy that had been centered in

Alexandria Alexandria ( or ; ar, ٱلْإِسْكَنْدَرِيَّةُ ; grc-gre, Αλεξάνδρεια, Alexándria) is the second largest city in Egypt, and the largest city on the Mediterranean coast. Founded in by Alexander the Great, Alexandri ...

Egypt Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a List of transcontinental countries, transcontinental country spanning the North Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via a land bridg ...

. His was the first to attempt to relate the Greek with the traditional

Arabic Arabic (, ' ; , ' or ) is a Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C. E.Watson; Walter ...

star names and

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the earliest constellation ...

s, which were completely unrelated and overlapped in complicated ways.

Astronomy

Al-Sufi made his astronomical observations at a latitude of 32.7N° in

. It has been claimed that he identified the

Large Magellanic Cloud The Large Magellanic Cloud (LMC), or Nubecula Major, is a satellite galaxy of the Milky Way. At a distance of around 50 kiloparsecs (≈160,000 light-years), the LMC is the second- or third-closest galaxy to the Milky Way, after the ...

but this seems to be a misunderstanding of a reference to some stars south of Canopus which he admits he has not seen.Hafez, Ihsan; Stephenson, Richard; Orchiston, Wayne, (January 1, 2011
Abdul-Rahman al-Sufi and his Book of the Fixed Stars
pp. 121–138, , retrieved November 13, 2019 He also made the earliest recorded observation of the Andromeda Galaxy in 964, describing it as a "small cloud". This was the first

galaxy A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System ...

other than the

Milky Way The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. ...

to be mentioned in writing. Al-Sufi published ''Kitab al-Kawatib al-Thabit al-Musawwar'' (also commonly known as the ''Book of Fixed Stars'') in 964 and dedicated it to Adud al-Dawla, the ruler of

Buwayhid The Buyid dynasty ( fa, آل بویه, Āl-e Būya), also spelled Buwayhid ( ar, البويهية, Al-Buwayhiyyah), was a Shia Iranian dynasty of Daylamite origin, which mainly ruled over Iraq and central and southern Iran from 934 to 1062. Coup ...

at the time. This book describes 48 constellations and the stars that are part of those constellations. Within the ''Book of Fixed Stars'', Al-Sufi compared Greek and Arabic constellations and stars linking those there were the same in both texts. He included two illustrations of each constellation, one showing the orientation of the stars from the perspective outside the

celestial globe Celestial globes show the apparent positions of the stars in the sky. They omit the Sun, Moon, and planets because the positions of these bodies vary relative to those of the stars, but the ecliptic, along which the Sun moves, is indicated. ...

and the other from the perspective of looking at the sky while standing on the earth. He separated the constellations into three groups: twenty-one northern constellations, twelve zodiac constellations, and fifteen southern constellations. For each of these forty-eight constellations, Al-Sufi provided a star chart that contains all of the stars that form the constellation. Each star chart comprised names and numbers of the individual stars in the constellation, and provided their longitudinal and latitudinal coordinates, the magnitude or brightness of each star, and its location north or south of the ecliptic. Although the magnitude was given for each star, of the 35 remaining copies of the ''Book of Fixed Stars'' the star magnitudes are not consistently the same number for each star due to scribing errors. Al-Sufi organized the stars in each of his drawings into two groups: the stars that form the image that the constellation is meant to depict, and the stars that are in close proximity to the constellation but do not contribute to the overall image. He identified and described stars not included by Ptolemy, but he did not include them in his star charts. Al-Sufi states at the beginning of the '' Book of Fixed Stars'' that his charts are modeled after those that were produced by Ptolemy, so Al-Sufi left the stars excluded in Ptolemy's charts out of his charts as well. Ptolemy had published the ''Almagest'' 839 years earlier than Al-Sufi'','' so the longitudinal placement of the stars within constellations had changed over that time. To account for the procession of the stars, Al-Sufi added 12° 42' to the longitudes Ptolemy had previously suggested for the placement of the stars. Al-Sufi differed in Ptolemy by having a three level scale to measure the magnitude of stars instead of a two level scale. This extra level increased the accuracy of his measurements. His methodology for determining these magnitude measurements cannot be found in any of his remaining texts. Despite the importance of the Book of Fixed Stars in the history of astronomy, it took more than a thousand years until the first English translation was published in 2010. Al-Sufi observed that the ecliptic plane is inclined with respect to the celestial equator and quite accurately calculated the length of the

tropical year A tropical year or solar year (or tropical period) is the time that the Sun takes to return to the same position in the sky of a celestial body of the Solar System such as the Earth, completing a full cycle of seasons; for example, the time ...

. Al-Sufi also wrote about the

astrolabe An astrolabe ( grc, ἀστρολάβος ; ar, ٱلأَسْطُرلاب ; persian, ستاره‌یاب ) is an ancient astronomical instrument that was a handheld model of the universe. Its various functions also make it an elaborate inclin ...

, finding numerous additional uses for it: he described over 1000 different uses, in areas as diverse as

astronomy Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...

, astrology, horoscopes,

navigation Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation ...

surveying Surveying or land surveying is the technique, profession, art, and science of determining the terrestrial two-dimensional or three-dimensional positions of points and the distances and angles between them. A land surveying professional is ...

time Time is the continued sequence of existence and event (philosophy), events that occurs in an apparently irreversible process, irreversible succession from the past, through the present, into the future. It is a component quantity of various me ...

keeping,

Qibla The qibla ( ar, قِبْلَة, links=no, lit=direction, translit=qiblah) is the direction towards the Kaaba in the Sacred Mosque in Mecca, which is used by Muslims in various religious contexts, particularly the direction of prayer for the ...

and Salat prayer. Al-Sufi's astronomical work was subsequently used by many other astronomers, including Ulugh Beg who was both a prince and astronomer.

Legacy

The lunar crater Azophi and the minor planet 12621 Alsufi are named after him. Astronomy Society of Iran – Amateur Committee (ASIAC) has held an international Sufi Observing Competition in memory of Al-Sufi. The first competition was held in 2006 in the north of Semnan Province and the second was held in the summer of 2008 in Ladiz near the Zahedan. More than 100 attendees from Iran and Iraq participated in the events. On December 7, 2016, Google Doodle commemorated his 1113th birthday.

Gallery

File:Constellation Taureau - al-Sufi.jpg, Constellation Taurus File:Constellation Crabe - al-Sufi.jpg, Constellation

Cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...

File:Constellation lièvre - al-Sufi.jpg, Constellation Lepus File:Constellation Gemeaux - al-Sufi.jpg, Constellation Gemini File:Folio 165 from manuscript of as-Sufi treatese on the fixed stars. 1009-10. Bodleian Library, Oxford..jpg, Constellation Andromeda File:Azophi Ophiuchus.jpg, Constellation Ophiuchus

Citations

General sources

"Abd al-Rahman Al-Sufi's (Azophi) 1113th Birthday"
Google.com. December 7, 2016. * Al-Qifti. ''Ikhbar al-'ulama' bi-akhbar al-hukama'' (''History of Learned Men''). In: ''Άbdul-Ramān al-Şūfī and his Book of the Fixed Stars: A Journey of Re-discovery'' by Ihsan Hafez, Richard F. Stephenson, Wayne Orchiston (2011). In: Orchiston, Wayne, ''Highlighting the history of astronomy in the Asia-Pacific region: proceedings of the ICOA-6 conference. Astrophysics and Space Science Proceedings''. New York: Springer. . "... is the honored, the perfect, the most intelligent and the friend of the King Adud al-Dawla Fanakhasru Shahenshah Ibn Buwaih. He is the author of the most honored books in the science of astronomy. He was originally from Nisa and is of a Persian descent." * "Archived copy". Archived from the original on 2009-10-20. Retrieved 2009-01-07. * Cavin, Jerry D. (2012). The amateur Astronomer's Guide to the Deep-Sky Catalogs. Springer Science+Business Media, LLC. . OCLC 759795491. * Dr. Emily Winterburn (National Maritime Museum) (2005). "Using an Astrolabe". Foundation for Science Technology and Civilisation. Retrieved 2008-01-22. * Hafez, Ihsan; Stephenson, Richard; Orchiston, Wayne, (2011-01-01), Abdul-Rahman al-Sufi and his Book of the Fixed Stars, pp. 121–138, , retrieved 2019-11-13. * Kepple, George Robert; Glen W. Sanner (1998). ''The Night Sky Observer's Guide''. 1. Willmann-Bell. p. 18. . * Knobel, E. B. (June 1885). "On Al Sufi's star magnitudes". ''Monthly Notices of the Royal Astronomical Society''. 45: 417–425. * "Observatoire de Paris (Abd-al-Rahman Al Sufi)". Archived from the original on April 16, 2007. Retrieved 2007-04-19. * "Observatoire de Paris (LMC)". Archived from the original on April 17, 2007. Retrieved 2007-04-19. * Orchiston, Wayne; Green, David A.; Strom, Richard (2014-11-24). ''New Insights From Recent Studies in Historical Astronomy: Following in the Footsteps of F. Richard Stephenson: A Meeting to Honor F. Richard Stephenson on His 70th Birthday''. Springer. . * Robert Harry van Gent. ''Biography of al-Sūfī''. "The Persian astronomer Abū al-Husayn ‘Abd al-Rahmān ibn ‘Umar al-Sūfī was born in Rayy (near Tehrān) on 7 December 903

and died in Baghdād on 25 May 986 3 Muharram 376 H... the Persian astronomer Abū al-Husayn ‘Abd al-Rahmān ibn ‘Umar al-Sūfī who was commonly known by European astronomers as Azophi Arabus". University of Utrecht, Netherlands. Retrieved 2014-01-11. * Schaefer, Bradley E. (2013-02). "The Thousand Star Magnitudes in the Catalogues of Ptolemy, Al Sufi, and Tycho are All Corrected for Atmospheric Extinction". ''Journal for the History of Astronomy''. 44 (1): 47-A91. . . * Selin, Helaine (2008). ''Encyclopedia of the history of science, technology, and medicine in non-western cultures''. Berlin; New York: Springer. p. 160. . Al-Sūfī was an astronomer in the Arabic-Islamic area. He was of Persian origin, but wrote in Arabic, the language of all science in that time. * Upton, Joseph M. (March 1933). "A Manuscript of 'The Book of the Fixed Stars' by ʿAbd Ar-Rahmān As-Sūfī". ''Metropolitan Museum Studies''. 4: 179–197. . .

External links

Liber locis stellarum fixarum, 964 da www.atlascoelestis.com

* ttp://www.atlascoelestis.com/ulug%201436%20Pagina.htm Ulug Beg in www.atlascoelestis.com
Al-Sufi's constellations

{{DEFAULTSORT:Sufi, Abd Al-Rahman Al- 10th-century Iranian astronomers 903 births 986 deaths Scholars under the Buyid dynasty Greek–Arabic translators People from Ray, Iran