{{Short description|none}}
[[File:Astrolabe-Persian-18C.jpg|thumb|18th century Persian brass [[astrolabe]] at the [[Whipple Museum of the History of Science]] in [[Cambridge]], England. The astrolabe consists of a disk engraved with the positions of the celestial bodies.]]

'''Medieval Islamic astronomy''' comprises the [[Astronomy|astronomical]] developments made in the [[Islamic world]], particularly during the [[Islamic Golden Age]] (9th–13th centuries), and mostly written in the [[Arabic language]]. These developments mostly took place in the [[Middle East]], [[Central Asia]], [[Al-Andalus]], and [[North Africa]], and later in the [[Far East]] and [[History of India|India]]. It closely parallels the genesis of other [[Islamic science]]s in its assimilation of foreign material and the amalgamation of the disparate elements of that material to create a science with [[Islam]]ic characteristics. These included [[Greek astronomy|Greek]], [[Sassanid Empire|Sassanid]], and [[Indian astronomy|Indian works]] in particular, which were translated and built upon.

Islamic astronomy played a significant role in the revival of ancient astronomy following the [[Dark Ages (historiography)|loss of knowledge]] during the [[early medieval period]], notably with the production of [[Middle Latin|Latin]] translations of Arabic works [[Latin translations of the 12th century|during the 12th century]].

A significant number of stars in the sky, such as [[Aldebaran]], [[Altair]] and [[Deneb]], and astronomical terms such as [[alidade]], [[azimuth]], and [[nadir (astronomy)|nadir]], are still referred to by their [[List of Arabic star names|Arabic]] names. A large corpus of literature from Islamic astronomy remains today, numbering approximately 10,000 manuscripts scattered throughout the world, many of which have not been read or catalogued. Even so, a reasonably accurate picture of Islamic activity in the field of astronomy can be reconstructed.

== History ==

{{See also|Cosmology in medieval Islam#Cosmology in the medieval Islamic world}}

=== Pre-Islamic Arabs ===

The Islamic historian [[Ahmad Dallal]] notes that, unlike the [[Babylonian astronomy|Babylonians]], [[Ancient Greek astronomy|Greeks]], and [[Indian astronomy|Indians]], who had developed elaborate systems of mathematical [[astronomical]] study, the [[Pre-Islamic Arabia|pre-Islamic Arabs]] relied upon [[Empirical evidence|empirical observations]]. These were based on the rising and setting of particular stars, and this indigenous [[constellation]] tradition was known as ''{{lang|ar|Anwā’}}''. The study of ''{{lang|ar|Anwā’}}'' was developed after [[Islamization]] when Arab astronomers introduced mathematics to their study of the night sky.{{sfn|Dallal|1999|p=162}}

=== Early period===
The first astronomical texts that were translated into [[Arabic]] were of Indian{{sfn|Sachau|1910|p=xxxi}} and Persian origin.{{sfn|Dallal|2010|p=29}} The most notable was ''[[Zij al-Sindhind]]'', a ''[[zij]]'' produced by [[Muḥammad ibn Ibrāhīm al-Fazārī]] and [[Yaʿqūb ibn Ṭāriq]], who translated an 8th-century Indian astronomical work after 770, with the assistance of Indian astronomers who were at the court of caliph [[Al-Mansur]].{{sfn|Sachau|1910|p=xxxi}}{{better source needed|reason=old source|date=January 2023}} ''{{lang|ar|Zij al-Shah}}'' was also based upon Indian [[Ephemeris|astronomical tables]], compiled in the [[Sasanian Empire]] over a period of two centuries. Fragments of texts during this period show that Arab astronomers adopted the [[Sine and cosine|sine function]] from India in place of the [[chord (geometry)|chords]] of [[Arc (geometry)|arc]] used in [[History of trigonometry#Classical antiquity|Greek trigonometry]].{{sfn|Dallal|1999|p=162}}

Ptolemy's Almagest (a geocentric spherical Earth cosmic model) was translated at least five times in the late eighth and ninth centuries,<ref>King, David A., "[https://www.academia.edu/attachments/55944098/download_file?s=portfolio Islamic Astronomy]", In Walker, Christopher, ''Astronomy before the Telescope'', London: British Museum Press, pp. 143-174, (P148) {{ISBN|978-0-7141-2733-0}}, 1996</ref> which was the main authoritative work that informed the Arabic astronomical tradition.<ref>Dallal, Ahmad. ''Islam, Science, and the Challenge of History (The Terry Lectures Series)'' . Yale University Press. 2012. [https://yalebooks.co.uk/book/9780300177718/islam-science-and-the-challenge-of-history/ 9780300177718]. pp. 135. Kindle Location 947.</ref>

The rise of [[Islam]], with its obligation to determine the five daily [[prayer times]] and the [[qibla]] (the direction towards the [[Kaaba]] in the [[Masjid al-Haram|Sacred Mosque]] in [[Mecca]]) inspired intellectual progress in astronomy.{{sfn|King|2005|p=xvii }}

=== Astronomical methods ===
The [[philosopher]] [[Al-Farabi]] (d. 950) described astronomy in terms of mathematics, music, and optics. He showed how astronomy could be used to describe the Earth's motion, and the position and movement of celestial bodies, and separated mathematical astronomy from science, restricting astronomy to describing the position, shape, and size of distant objects.{{sfn|Janos|2010|pp=243{{ndash}}245}} Al-Farabi used the writings of [[Ptolemy]], as described in his [[Analemma]], a way of calculating the Sun's position from any fixed location.{{sfn|Sidoli|2020|p=45}}

===Golden Age===
[[File:Tusi couple.jpg|thumb|The [[Tusi-couple]] is a mathematical device invented by [[Nasir al-Din al-Tusi]] in which a small [[circle]] rotates inside a larger circle twice the [[diameter]] of the smaller [[circle]]. Rotations of the circles cause a point on the [[circumference]] of the smaller circle to [[oscillate]] back and forth in [[linear motion]] along a diameter of the larger circle.]]

[[House of Wisdom|The House of Wisdom]] was an academy that was open to the public and financially supported during the reign of the Abbasid caliph [[al-Ma'mun]] in the early 9th century in Baghdad. Astronomical research was greatly supported by al-Mamun through the House of Wisdom, al-Ma'mun also built the first observatory in Baghdad and subsequent observatories were built around regions of [[Lower Mesopotamia|Iraq]] and [[Persis|Iran]].<ref>{{Cite web |title=Al-Maʾmūn {{!}} EBSCO Research Starters |url=https://www.ebsco.com/research-starters/biography/al-mamun |access-date=2025-04-16 |website=www.ebsco.com |language=en}}</ref><ref>{{Cite web |last=Stirone |first=Shannon |date=2017-02-14 |title=How Islamic scholarship birthed modern astronomy |url=https://www.astronomy.com/science/how-islamic-scholarship-birthed-modern-astronomy/ |access-date=2025-04-16 |website=Astronomy Magazine |language=en-US}}</ref>

The first major Muslim work of astronomy was ''Zij al-Sindhind'', produced by the mathematician [[Muhammad ibn Musa al-Khwarizmi]] in 830. It contained tables for the movements of the Sun, the Moon, and the planets [[Mercury (planet)|Mercury]], [[Venus]], [[Mars]], [[Jupiter]] and [[Saturn]]. The work introduced Ptolemaic concepts into Islamic science, and marked a turning point in Islamic astronomy, which had previously concentrated on translating works, but which now began to develop new ideas.{{sfn|Dallal|1999|p=163}} Another notable figure in al-Ma'mun's court was [[Sanad ibn Ali|Sind ibn 'Alī]], a Jewish convert to Islam, who contributed to the ''Zīj al-Sindhind'' and was credited with constructing astronomical instruments.<ref name=":3">{{Citation |last1=Ferrario |first1=Gabriele |chapter=Science and Medicine |date=2021 |title=The Cambridge History of Judaism: Volume 5: Jews in the Medieval Islamic World |volume=5 |pages=828 |editor-last=Lieberman |editor-first=Phillip I. |chapter-url=https://www.cambridge.org/core/books/cambridge-history-of-judaism/science-and-medicine/AC6F034D01994F6501EA22A2B0558C76 |access-date=2025-07-14 |series=The Cambridge History of Judaism |place=Cambridge |publisher=Cambridge University Press |isbn=978-0-521-51717-1 |last2=Kozodoy |first2=Maud}}</ref>

Jewish scholars in the Islamic world also engaged with astronomical methods developed by their Muslim counterparts. In 931, [[Saadia Gaon]] (a leading rabbi and head of the [[Sura Academy]] in Iraq) used a ''zīj'' to calculate the positions of the sun, moon, and five visible planets at a specific time, as noted in his commentary on ''Sefer Yetzirah''. He may have studied the ''zīj'' tradition in part to counter contemporaries who sought to use such calculations to determine and sanctify the new moon each month.<ref name=":3" />

=== Doubts on Ptolemy ===

In 850, the [[Abbasid]] astronomer [[Al-Farghani]] wrote ''{{lang|ar|Kitab fi Jawami}}'' ("A compendium of the science of stars"). The book gave a summary of Ptolemic [[cosmography]]. However, it also corrected Ptolemy based on the findings of earlier Arab astronomers. Al-Farghani gave revised values for the [[obliquity of the ecliptic]], the [[precession]] of the [[apogee]]s of the Sun and the Moon, and the [[circumference of the Earth]]. The book was circulated through the Muslim world, and translated into [[Latin]].{{sfn|Dallal|1999|p=164}}

By the 10th century, texts had appeared that doubted that Ptolemy's works were correct.{{sfn|Hoskin|1999|p=60}} Islamic scholars questioned the Earth's apparent immobility,{{sfn|Ragep|2001b}} and position at the centre of the universe, now that independent investigations into the [[Ptolemaic system]] were possible.{{sfn|Dallal|2010|p=31}}

The 10th century Egyptian astronomer [[Ibn Yunus]] found errors in Ptolemy's calculations. Ptolemy calculated that the Earth's angle of [[axial precession]] varied by one [[Degree (angle)|degree]] every 100 years. Ibn Yunus calculated the rate of change to be one degree every 70{{Frac|1|4}} years.{{citation needed|date=January 2023}}

Between 1025 and 1028, the [[polymath]] [[Ibn al-Haytham]] wrote his ''{{lang|ar|Al-Shukuk ala Batlamyus}}'' ("Doubts on Ptolemy"). While not disputing the existence of the [[geocentric model]], he criticized elements of the Ptolemy's theories. Other astronomers took up the challenge posed in this work, and went on to develop alternate models that resolved the difficulties identified by Ibn al-Haytham. In 1070, [[Abu Ubayd al-Juzjani]] published the ''{{lang|ar|Tarik al-Aflak}}'', in which he discussed the issues arising from Ptolemy's theory of [[equant]]s, and proposed a solution. The anonymous work ''{{lang|ar|al-Istidrak ala Batlamyus}}'' ("Recapitulation regarding Ptolemy"), produced in [[Al-Andalus]], included a list of objections to Ptolemic astronomy.{{Citation needed|date=January 2023}}

[[Nasir al-Din al-Tusi]] also exposed problems present in Ptolemy's work. In 1261, he published his {{lang|ar|Tadkhira}}, which contained 16 fundamental problems he found with Ptolemaic astronomy,{{sfn|Saliba|1993}} and by doing this, set off a chain of Islamic scholars that would attempt to solve these problems. Scholars such as [[Qutb al-Din al-Shirazi]], Ibn al-Shatir, and [[Shams al-Din al-Khafri]] all worked to produce new models for solving Tusi's 16 Problems,<ref>{{Cite journal |last=Saliba |first=George |date=1994-02-01 |title=A Sixteenth-Century Arabic Critique of Ptolemaic Astronomy: The Work of Shams Al-Din Al-Khafri |url=https://doi.org/10.1177/002182869402500102 |journal=Journal for the History of Astronomy |language=en |volume=25 |issue=1 |pages=15–38 |doi=10.1177/002182869402500102 |bibcode=1994JHA....25...15S |s2cid=117456123 |issn=0021-8286|url-access=subscription }}</ref> and the models they worked to create would become widely adopted by astronomers for use in their own works. 
[[File:TusiCouple.gif|thumb|This model presenting how Nasir al-Din al-Tusi explain the motion of Earth, relative to the Moon and the Sun using the Tusi couple. It is used to support that Earth rotates around something, and equant is not the correct way to explain the motion of the Moon around Earth.]]
Nasir al-Din Tusi wanted to use the concept of Tusi couple to replace the "equant" concept in Ptolemic model. Since the equant concept would result in the Moon distance to change dramatically through each month, at least by the factor of two if the math is done. But with the Tusi couple, the Moon would just rotate around Earth resulting in the correct observation and applied concept.<ref>{{Cite book |last=Pedersen |first=Olaf |title=Early Physics and Astronomy |publisher=Cambridge: Cambridge University Press |year=1993 |pages=215–220}}</ref> [[Mu'ayyad al-Din al-Urdi]] was another engineer/scholar that tried to make sense of the motion of planets. He came up with the concept of lemma, which is a way of representing the epicyclical motion of planets without using Ptolemic method. Lemma was intended to replace the concept of equant as well.

==== Earth rotation ====
[[File:Lunar phases al-Biruni.jpg|thumb|An illustration from [[al-Biruni]]'s astronomical works that explains the different [[phases of the moon]], with respect to the position of the [[Sun]].]]

[[Abu Rayhan Biruni]] (b. 973) discussed the possibility of whether the Earth rotated about its own axis and around the Sun, but in his ''Masudic Canon'', he set forth the principles that the Earth is at the center of the universe and that it has no motion of its own.<ref>E. S. Kennedy, "Al-Bīrūnī's Masudic Canon", ''Al-Abhath'', 24 (1971): 59–81; reprinted in David A. King and Mary Helen Kennedy, ed., ''Studies in the Islamic Exact Sciences,'' Beirut, 1983, pp. 573–595.</ref> He was aware that if the Earth rotated on its axis, this would be consistent with his astronomical parameters,<ref>G. Wiet, V. Elisseeff, P. Wolff, J. Naudu (1975). ''History of Mankind, Vol 3: The Great medieval Civilisations'', p. 649. George Allen & Unwin Ltd, [[UNESCO]].</ref> but he considered this a problem of [[natural philosophy]] rather than mathematics.<ref name=young />

His contemporary, [[Abu Sa'id al-Sijzi]], accepted that the Earth rotates around its axis.<ref name=Scientia>{{Cite journal |volume=108 |issue=67 |pages=762 |first=Alessandro |last=Bausani |title=Cosmology and Religion in Islam |journal=Scientia/Rivista di Scienza |date=1973}}</ref> Al-Biruni described an [[astrolabe]] invented by Sijzi based on the idea that the earth rotates.{{sfn|Nasr1993|pp=135{{ndash}}136}}

The fact that some people did believe that the Earth is moving on its own axis is further confirmed by an Arabic reference work from the 13th century which states:<blockquote>According to the geometers [or engineers] (''muhandisīn''), the earth is in a constant circular motion, and what appears to be the motion of the heavens is actually due to the motion of the earth and not the stars.<ref name=young>{{Cite book| publisher = [[Cambridge University Press]]| isbn = 978-0-521-02887-5| editor-last1 = Young| editor-first1 = M. J. L.| title = Religion, Learning and Science in the 'Abbasid Period| date = 2006-11-02|page=[https://archive.org/stream/M.J.L.YoungJ.D.LathamR.B.SerjeantEdsReligionLearningAndScienceInTheAbbasidPeriod/M.%20J.%20L.%20Young%2C%20J.%20D.%20Latham%2C%20R.%20B.%20Serjeant%20eds%20Religion%2C%20Learning%20and%20Science%20in%20the%20%60Abbasid%20Period#page/n217/mode/1up 413]}}</ref></blockquote>

At the [[Maragheh observatory|Maragha]] and [[Ulugh Beg Observatory|Samarkand observatories]], the [[Earth's rotation]] was discussed by [[Najm al-Din al-Qazwini al-Katibi]] (d. 1277),<ref>''[https://archive.org/details/Hikmat3ayn Hikmat al-'Ain]'', p. 78</ref> Tusi (b. 1201) and [[Ali Qushji|Qushji]] (b. 1403). The arguments and evidence used by Tusi and Qushji resemble those used by Copernicus to support the Earth's motion.<ref name=Ragep>{{Citation |last=Ragep |first=F. Jamil |year=2001a |title=Tusi and Copernicus: The Earth's Motion in Context |journal=Science in Context |volume=14 |issue=1–2 |pages=145–163 |publisher=[[Cambridge University Press]] |doi=10.1017/s0269889701000060 |s2cid=145372613 }}</ref><ref name=Ragep2>{{Citation |last1=Ragep |first1=F. Jamil |editor1-last=Brooke |editor1-first=John Hedley |editor1-link=John Hedley Brooke |editor2-last=Osler |editor2-first= Margaret J. |editor2-link=Margaret J. Osler |editor3-last=van der Meer |editor3-first= Jitse M. |year=2001b |title=Freeing Astronomy from Philosophy: An Aspect of Islamic Influence on Science |journal=Osiris |series=2nd Series |volume=16 |issue=Science in Theistic Contexts: Cognitive Dimensions |pages=49–64 & 66–71 |bibcode=2001Osir...16...49R |doi=10.1086/649338 |last2=Al-Qushji |first2=Ali |s2cid=142586786 |url=https://escholarship.mcgill.ca/concern/articles/m326m556v }}</ref> However, it remains a fact that the Maragha school never made the big leap to [[heliocentrism]].{{sfn|Huff|1993}}

==== Alternative geocentric systems ====

In the 12th century, non-heliocentric alternatives to the Ptolemaic system were developed by some Islamic astronomers in al-Andalus, following a tradition established by [[Ibn Bajjah]], [[Ibn Tufail]], and [[Ibn Rushd]].

A notable example is [[Nur ad-Din al-Bitruji]], who considered the Ptolemaic model mathematical, and not physical.{{sfn|Samsó|1980}} Al-Bitruji proposed a theory on [[planetary motion]] in which he wished to avoid both [[Deferent and epicycle|epicycles and eccentrics]].<ref>[[Bernard R. Goldstein]] (March 1972). "Theory and Observation in Medieval Astronomy", ''Isis'' '''63''' (1), p. 39-47 [41].</ref> He was unsuccessful in replacing Ptolemy's planetary model, as the numerical predictions of the planetary positions in his configuration were less accurate than those of the Ptolemaic model.<ref>[http://www.bookrags.com/research/ptolemaic-astronomy-islamic-planeta-scit-021234 Ptolemaic Astronomy, Islamic Planetary Theory, and Copernicus's Debt to the Maragha School], ''Science and Its Times'', [[Thomson Gale]].(inaccessible document)</ref> One original aspects of al-Bitruji's system is his proposal of a physical cause of celestial motions. He contradicts the Aristotelian idea that there is a specific kind of dynamics for each world, applying instead the same dynamics to the sublunar and the celestial worlds.{{sfn|Samsó|2007}}

=== Later period ===

In the late 13th century, Nasir al-Din al-Tusi created the Tusi couple, as pictured above. Other notable astronomers from the later medieval period include [[Mu'ayyad al-Din al-Urdi]] ({{Circa|1266}}), [[Qutb al-Din al-Shirazi]] ({{Circa|1311}}), [[Sadr al-Sharia al-Bukhari]] ({{Circa|1347}}), [[Ibn al-Shatir]] ({{Circa|1375}}), and [[Ali Qushji]] ({{Circa|1474}}).{{sfn|Dallal|1999|p=171}}

In the 15th century, the [[Timurid Empire|Timurid]] ruler [[Ulugh Beg]] of [[Samarkand]] established his court as a center of patronage for astronomy. He studied it in his youth, and in 1420 ordered the construction of Ulugh Beg Observatory, which produced a new set of astronomical tables, as well as contributing to other scientific and mathematical advances.<ref>{{New Cambridge History of Islam |last=Subtelny |first=Maria E. |volume=3 |chapter=Tamerlane and his descendants: from paladins to patrons |pages=184–5}}</ref>

Several major astronomical works were produced in the early 16th century, including ones by [[Al-Birjandi]] (d. 1525 or 1526) and Shams al-Din al-Khafri (fl. 1525). However, the vast majority of works written in this and later periods in the history of Islamic sciences are yet to be studied.<ref name=Ragep2 />

==Influences==
===Africa===
Islamic astronomy influenced [[Timbuktu Manuscripts|Malian astronomy]].<ref>{{Cite book |url=https://books.google.com/books?id=4DJpDW6IAukC&pg=PA180 |title=African Cultural Astronomy: Current Archaeoastronomy and Ethnoastronomy research in Africa |publisher=[[Springer Science & Business Media]] |isbn=978-1-4020-6639-9 |editor-last=Holbrook |editor-first=Jarita |date=1 January 2008 |language=en |access-date=11 November 2016 |editor-last2=Medupe |editor-first2=Rodney Thebe |editor-last3=Urama |editor-first3=Johnson O.}}</ref>

=== Europe ===

[[File:Shatir500.jpg|thumb|[[Ibn al-Shatir]]'s model for the appearances of [[Mercury (planet)|Mercury]], showing the multiplication of [[Deferent and epicycle|epicycles]] using the [[Tusi-couple]], thus eliminating the Ptolemaic eccentrics and [[equant]].]]

Several works of Islamic astronomy were translated to Latin [[Latin translations of the 12th century|starting from the 12th century]].

The work of [[al-Battani]] (d. 929), ''Kitāb az-Zīj'' ("Book of [[zij|Astronomical Tables]]"), was frequently cited by European astronomers and received several reprints, including one with annotations by [[Regiomontanus]].<ref name="B1911">{{Cite EB1911|wstitle=Albategnius |volume=1 |page=491}}</ref> [[Nicolaus Copernicus]], in his book that initiated the [[Copernican Revolution]], the ''[[De revolutionibus orbium coelestium]]'', mentioned al-Battani no fewer than 23 times,{{sfn|Hoskin|1999|p=58}} and also mentions him in the ''[[Commentariolus]]''.<ref name=freely>{{Cite book |publisher=[[I.B.Tauris]] |isbn=978-1-78453-138-6 |last=Freely |first=John |title=Light from the East: How the Science of Medieval Islam Helped to Shape the Western World |date=2015-03-30 |page=179}}</ref> [[Tycho Brahe]], [[Giovanni Battista Riccioli]], [[Johannes Kepler]], [[Galileo Galilei]], and others frequently cited him or his observations.<ref name="Hartner 2008">{{cite encyclopedia |last=Hartner |first=Willy |title=Al-Battānī, Abū ʿAbd Allāh Muḥammad Ibn Jābir Ibn Sinān al-Raqqī al-Ḥarrānī al–Ṣābi |encyclopedia=[[Dictionary of Scientific Biography]] |publisher=[[Charles Scribner's Sons]] |location=New York |date=1970–80 |isbn=978-0-684-10114-9 |url=http://www.encyclopedia.com/doc/1G2-2830900300.html}}</ref> His data is still used in geophysics.<ref>Dalmau, W. (1997) [http://hbar.phys.msu.ru/gorm/atext/dalmau.htm CRITICAL REMARKS ON THE USE OF MEDIEVAL ECLIPSE RECORDS FOR THE DETERMINATION OF LONG-TERM CHANGES IN THE EARTH'S ROTATION] {{Webarchive|url=https://web.archive.org/web/20121023161207/http://hbar.phys.msu.ru/gorm/atext/dalmau.htm |date=2012-10-23 }}', Surveys in Geophysics 18: 213–223.</ref>

Around 1190, [[al-Bitruji]] published an alternative geocentric system to Ptolemy's model. His system spread through most of Europe during the 13th century, with debates and refutations of his ideas continued to the 16th century.{{sfn|Samsó|1980}} In 1217, [[Michael Scot]] finished a Latin translation of al-Bitruji's ''Book of Cosmology'' (''Kitāb al-Hayʾah''), which became a valid alternative to Ptolemy's ''[[Almagest]]'' in [[Scholasticism|scholasticist circles]].{{sfn|Samsó|2007}} Several European writers, including [[Albertus Magnus]] and [[Roger Bacon]], explained it in detail and compared it with Ptolemy's.{{sfn|Samsó|1980}} Copernicus cited his system in the ''De revolutionibus'' while discussing theories of the order of the inferior planets.{{sfn|Samsó|1980}}{{sfn|Samsó|2007}}

Some historians maintain that the thought of the Maragheh observatory, in particular the mathematical devices known as the [[Urdi lemma]] and the Tusi couple, influenced Renaissance-era European astronomy and thus Copernicus.<ref>{{cite journal |last1=Roberts |first1=V. |last2=Kennedy |first2=E. S. |date=1959 |title=The Planetary Theory of Ibn al-Shatir |journal=[[Isis (journal)|Isis]] |volume=50 |issue=3 |pages=232–234 |doi=10.1086/348774 |s2cid=143592051}}</ref><ref>{{Citation |last=Guessoum |first=N. |date=June 2008 |title=Copernicus and Ibn Al-Shatir: does the Copernican revolution have Islamic roots? |journal=The Observatory |volume=128 |pages=231–239 [238] |bibcode=2008Obs...128..231G}}</ref>{{sfn|Sabra|1998}}<ref>{{citation|title=Late Medieval Planetary Theory |author=E. S. Kennedy|journal=[[Isis (journal)|Isis]]|volume=57|issue=3|date=Autumn 1966|pages=365–378 [377]|doi=10.1086/350144|jstor=228366|s2cid=143569912}}</ref> 
Copernicus used such devices in the same planetary models as found in Arabic sources.<ref name=Saliba95>{{Cite book |publisher=NYU Press |isbn=978-0-8147-8023-7 |last=Saliba |first=George |title=A History of Arabic Astronomy: Planetary Theories During the Golden Age of Islam |date=1995-07-01}}</ref> 
Furthermore, the exact replacement of the [[equant]] by two [[epicycles]] used by Copernicus in the ''Commentariolus'' was found in an earlier work by Ibn al-Shatir (d. {{Circa|1375}}) of Damascus.<ref name=Swerdlow>{{Cite journal |issn=0003-049X |volume=117 |issue=6 |page=424 |last=Swerdlow |first=Noel M. |title=The Derivation and First Draft of Copernicus's Planetary Theory: A Translation of the Commentariolus with Commentary |journal=Proceedings of the American Philosophical Society |date=1973-12-31 |jstor=986461 |bibcode=1973PAPhS.117..423S}}</ref> Copernicus' lunar and Mercury models are also identical to Ibn al-Shatir's.<ref>{{cite encyclopedia |editor=Thomas Hockey |display-editors=etal |last=King |first=David A. |title=Ibn al-Shāṭir: ʿAlāʾ al-Dīn ʿAlī ibn Ibrāhīm |encyclopedia=The Biographical Encyclopedia of Astronomers |publisher=Springer |date=2007 |location=New York |pages=569–70 |url=http://islamsci.mcgill.ca/RASI/BEA/Ibn_al-Shatir_BEA.htm |isbn=978-0-387-31022-0}} ([http://islamsci.mcgill.ca/RASI/BEA/Ibn_al-Shatir_BEA.pdf PDF version])</ref>

While the influence of the criticism of Ptolemy by [[Averroes]] on Renaissance thought is clear and explicit, the claim of direct influence of the Maragha school, postulated by [[Otto E. Neugebauer]] in 1957, remains an open question.{{sfn|Huff|1993}}<ref>N.K. Singh, M. Zaki Kirmani,''Encyclopaedia of Islamic science and scientists''[https://books.google.com/books?id=lKa9khFcKmQC&q=geocentric&pg=PA808]</ref><ref>Viktor Blåsjö, "A Critique of the Arguments for Maragha Influence on Copernicus", ''Journal for the History of Astronomy'', '''45''' (2014), 183–195 [http://adsabs.harvard.edu/abs/2014JHA....45..183B ADS].</ref> Since the Tusi couple was used by Copernicus in his reformulation of mathematical astronomy, there is a growing consensus that he became aware of this idea in some way. It has been suggested<ref>Claudia Kren, "The Rolling Device," p. 497.</ref><ref>[[George Saliba]], "Whose Science is Arabic Science in Renaissance Europe?" [http://www.columbia.edu/~gas1/project/visions/case1/sci.1.html]</ref> that the idea of the Tusi couple may have arrived in Europe leaving few manuscript traces, since it could have occurred without the translation of any Arabic text into Latin. One possible route of transmission may have been through [[Byzantine science]], which translated some of [[Nasīr al-Dīn al-Tūsī|al-Tusi]]'s works from Arabic into [[Medieval Greek|Byzantine Greek]]. Several Byzantine Greek manuscripts containing the Tusi-couple are still extant in Italy.<ref>{{cite web |author=George Saliba|author-link=George Saliba|title=Islamic Science and the Making of Renaissance Europe|website=[[Library of Congress]]|date=April 27, 2006 |url=https://www.loc.gov/today/cyberlc/feature_wdesc.php?rec=3883|access-date=2008-03-01}}</ref> Other scholars have argued that Copernicus could well have developed these ideas independently of the late Islamic tradition.{{sfn|Veselovsky|1973}} Copernicus explicitly references several astronomers of the "[[Islamic Golden Age]]" (10th to 12th centuries) in ''De Revolutionibus'': Albategnius (Al-Battani), Averroes (Ibn Rushd), [[Thābit ibn Qurra|Thebit (Thābit ibn Qurra)]], [[Al-Zarqali|Arzachel (Al-Zarqali)]], and Alpetragius (Al-Bitruji), but he does not show awareness of the existence of any of the later astronomers of the Maragha school.<ref name=freely />

It has been argued that Copernicus could have independently discovered the Tusi couple or took the idea from [[Proclus]]'s ''Commentary on the First Book of [[Euclid's Elements|Euclid]]'',<ref>{{Citation | last1 = Veselovsky | first1 = I. N. | year = 1973 | title = Copernicus and Nasir al-Din al-Tusi | url = http://articles.adsabs.harvard.edu/full/seri/JHA../0004//0000128.000.html | journal=Journal for the History of Astronomy | volume = 4 | issue = 2 | pages = 128–30 | postscript = . |bibcode = 1973JHA.....4..128V | doi = 10.1177/002182867300400205 | s2cid = 118453340 }}</ref> which Copernicus cited.<ref>{{Citation | last = Neugebauer | first = Otto | author-link = Otto E. Neugebauer | title = A History of Ancient Mathematical Astronomy | place = Berlin / Heidelberg / New York | publisher = Springer-Verlag | volume = 2 | year = 1975 | page = 1035 | isbn = 978-0-387-06995-1 }}</ref>
 
Another possible source for Copernicus's knowledge of this mathematical device is the ''Questiones de Spera'' of [[Nicole Oresme]], who described how a reciprocating linear motion of a celestial body could be produced by a combination of circular motions similar to those proposed by al-Tusi.<ref>{{Citation | last1 = Kren | first1 = Claudia | year = 1971 | title = The Rolling Device of Naṣir al-Dīn al-Ṭūsī in the ''De spera'' of Nicole Oresme | journal=Isis | volume = 62 | issue = 4| pages = 490–498 | doi = 10.1086/350791 | s2cid = 144526697 | postscript = . }}</ref>

===China===
[[File:Observatoire de Peking.jpg|thumb|Layout of the [[Beijing Ancient Observatory]].]]

Islamic influence on Chinese astronomy was first recorded during the [[Song dynasty]] when a [[Hui people|Hui]] [[Muslim]] astronomer named [[Ma Yize]] introduced the concept of seven days in a week and made other contributions.<ref>{{Cite book |url=https://books.google.com/books?id=ulSRAgAAQBAJ&pg=PA197 |title=Islam in the Era of Globalization: Muslim Attitudes Towards Modernity and Identity |last=Meuleman |first=Johan |publisher=[[Routledge]] |isbn=978-1-135-78829-2 |date=30 September 2005 |language=en |access-date=11 November 2016}}</ref>

Islamic astronomers were [[Islam in China|brought to China]] in order to work on calendar making and astronomy during the [[Mongol Empire]] and the succeeding [[Yuan dynasty]].<ref name="Rufus" /> The Chinese scholar [[Yelü Chucai|Yeh-lu Chu'tsai]] accompanied [[Genghis Khan]] to Persia in 1210 and studied their calendar for use in the Mongol Empire.<ref name="Rufus">{{citation|title=The Influence of Islamic Astronomy in Europe and the Far East |last=Rufus|first=W. C.|journal=Popular Astronomy |volume=47|issue=5|date=May 1939|pages=233–238 [237]|bibcode = 1939PA.....47..233R }}</ref> [[Kublai Khan]] brought Iranians to [[Beijing Ancient Observatory|Beijing to construct an observatory]] and an institution for astronomical studies.<ref name="theearth">Richard Bulliet, Pamela Crossley, Daniel Headrick, Steven Hirsch, Lyman Johnson, and David Northrup. ''The Earth and Its Peoples''. 3. Boston: Houghton Mifflin Company, 2005. {{ISBN|978-0-618-42770-3}}</ref>

Several Chinese astronomers worked at the Maragheh observatory, founded by Nasir al-Din al-Tusi in 1259 under the patronage of [[Hulagu Khan]] in Persia.<ref name="Walle">{{Cite book|url=https://books.google.com/books?id=Dw9gYo4Pk0MC|title=The history of the relations between the Low Countries and China in the Qing era (1644–1911)|last=vande Walle|first=Willy|publisher=[[Leuven University Press]]|year=2003|isbn=978-90-5867-315-2|editor-last=vande Walle|editor-first=W.F. |pages=38|access-date=11 November 2016|editor-last2=Golvers|editor-first2=Noel}}</ref> One of these Chinese astronomers was Fu Mengchi, or Fu Mezhai.<ref name="Dalen-19">{{citation|last=van Dalen|first=Benno|contribution=Islamic Astronomical Tables in China: The Sources for Huihui li|editor-last=Ansari|editor-first=S. M. Razaullah|year=2002|title=History of Oriental Astronomy|publisher=[[Springer Science+Business Media]]|isbn=978-1-4020-0657-9|pages=19–32 [19]}}</ref> In 1267, the Persian astronomer [[Jamal ad-Din (astronomer)|Jamal ad-Din]], who previously worked at Maragha observatory, presented Kublai Khan with seven [[#Instruments|Persian astronomical instruments]], including a terrestrial [[globe]] and an [[armillary sphere]],<ref>{{cite book |last=Zhu |first=Siben |author2=Walter Fuchs |title=The "Mongol Atlas" of China |year=1946 |publisher= [[Fu Jen Catholic University]] |location=[[Taipei]]}}</ref> as well as an astronomical [[almanac]], which was later known in China as the ''Wannian Li'' ("Ten Thousand Year Calendar" or "Eternal Calendar"). He was known as "Zhamaluding" in China, where, in 1271,<ref name="Dalen-19" /> he was appointed by Khan as the first director of the Islamic observatory in Beijing,<ref name="Walle" /> known as the Islamic Astronomical Bureau, which operated alongside the Chinese Astronomical Bureau for four centuries. Islamic astronomy gained a good reputation in China for its theory of planetary [[latitude]]s, which did not exist in Chinese astronomy at the time, and for its accurate prediction of eclipses.<ref name=":0">{{Cite book |title=Islamic Astronomical Tables in China: The Sources for Huihui li |last=Benno |first=van Dalen |work=History of Oriental Astronomy |year=2002 |isbn=978-94-015-9862-0 |editor-last=Ansari |editor-first=S.M. Razaullah |volume=274 |pages=19–32 |doi=10.1007/978-94-015-9862-0 |series=Astrophysics and Space Science Library |s2cid=128707624 }}</ref>

Some of the astronomical instruments constructed by the famous Chinese astronomer [[Guo Shoujing]] shortly afterwards resemble the style of instrumentation built at Maragheh.<ref name="Walle" /> In particular, the "simplified instrument" (''jianyi'') and the large [[gnomon]] at the [[Gaocheng Astronomical Observatory]] show traces of Islamic influence.<ref name=":0" /> While formulating the [[Chinese calendar|Shoushili calendar]] in 1281, Shoujing's work in [[spherical trigonometry]] may have also been partially influenced by [[Mathematics in medieval Islam|Islamic mathematics]], which was largely accepted at Kublai's court.<ref name="ho 105">Ho, Peng Yoke. (2000). ''Li, Qi, and Shu: An Introduction to Science and Civilization in China'', p. 105. Mineola: Dover Publications. {{ISBN|978-0-486-41445-4}}.</ref> These possible influences include a pseudo-geometrical method for converting between [[equator]]ial and [[Ecliptic coordinate system|ecliptic coordinates]], the systematic use of [[decimal]]s in the underlying parameters, and the application of [[cubic interpolation]] in the calculation of the irregularity in the planetary motions.<ref name=":0" />

[[Hongwu Emperor]] (r. 1368–1398) of the [[Ming dynasty]] (1328–1398), in the first year of his reign (1368), conscripted Han and non-Han astrology specialists from the astronomical institutions in Beijing of the former Mongolian Yuan to [[Nanjing]] to become officials of the newly established national observatory.

That year, the Ming government summoned for the first time the astronomical officials to come south from the upper capital of Yuan. There were fourteen of them. In order to enhance accuracy in methods of observation and computation, Hongwu Emperor reinforced the adoption of parallel calendar systems, the [[Han Chinese|Han]] and the Hui. In the following years, the Ming Court appointed several Hui astrologers to hold high positions in the Imperial Observatory. They wrote many books on Islamic astronomy and also manufactured astronomical equipment based on the Islamic system.

The translation of two important works into Chinese was completed in 1383: Zij (1366) and al-Madkhal fi Sina'at Ahkam al-Nujum, ''Introduction to Astrology'' (1004).

In 1384, a Chinese astrolabe was made for observing stars based on the instructions for making multi-purposed Islamic equipment. In 1385, the apparatus was installed on a hill in northern Nanjing.

Around 1384, during the Ming dynasty, Hongwu Emperor ordered the [[Chinese language|Chinese]] translation and compilation of Islamic astronomical tables, a task that was carried out by the scholars [[Mashayihei]], a Muslim astronomer, and [[Wu Bozong]], a Chinese scholar-official. These tables came to be known as the ''[[Huihui Lifa]]'' (''Muslim System of Calendrical Astronomy''), which was published in China a number of times until the early 18th century,<ref>{{citation |title=The Korean Adaptation of the Chinese-Islamic Astronomical Tables |date=10 January 2002 |author=Yunli Shi |journal=Archive for History of Exact Sciences |volume=57 |issue=1 |pages=25–60 [26] |doi=10.1007/s00407-002-0060-z |s2cid=120199426 |issn=1432-0657}}</ref> though the [[Qing dynasty]] had officially abandoned the tradition of Chinese-Islamic astronomy in 1659.<ref name="Shi-30">{{citation |title=The Korean Adaptation of the Chinese-Islamic Astronomical Tables |author=Yunli Shi |journal=Archive for History of Exact Sciences |issn=1432-0657 |volume=57 |issue=1 |date=January 2003 |doi=10.1007/s00407-002-0060-z |pages=25–60 [30] |s2cid=120199426}}</ref> The Muslim astronomer [[Yang Guangxian]] was known for his attacks on the Jesuit's astronomical sciences.

===Korea===
In the early [[Joseon]], the [[Islamic calendar]] served as a basis for calendar reform being more accurate than the existing Chinese-based calendars.<ref name="Baker">{{cite journal |last=Baker |first=Don |title=Islam Struggles for a Toehold in Korea |journal=Harvard Asia Quarterly |date=Winter 2006 |url=http://www.asiaquarterly.com/content/view/167/ |access-date=2007-04-23 |url-status=dead |archive-url=https://web.archive.org/web/20070517214927/http://www.asiaquarterly.com/content/view/167/ |archive-date=2007-05-17|quote=We can also see Muslim influence in the official calendars of the late Goryeo period.  After they gained control of China, the Mongols invited Arab astronomers to Beijing to correct mistakes that had crept into Chinese calculations of the movements of the sun, the moon, the five visible planets, and the stars. Those Muslim scientists brought with them the latest astronomical instruments as well as mathematical tools for predicting heavenly movements based on what those instruments revealed. The Korean government then sent their own astronomers to Beijing to learn from those Muslims. Even though there was nothing particularly religious about the calendar those Muslim scientists produced for East Asia, it became known unofficially as the Muslim Calendar. The government in both China and Korea continued to use Muslim calendrical techniques until the 16th century, when Christian missionaries from Europe brought even more advanced instruments and calculating techniques to China.}}</ref> A Korean translation of the ''[[Huihui Lifa]]'', a text combining [[Chinese astronomy]] with Islamic astronomy works of Jamal ad-Din, was studied in Joseon Korea during the time of [[Sejong the Great]] in the 15th century.<ref>{{Cite journal |title=The Korean Adaptation of the Chinese-Islamic Astronomical Tables |author=Yunli Shi |journal=Archive for History of Exact Sciences |issn=1432-0657 |volume=57 |issue=1 |date=January 2003 |doi=10.1007/s00407-002-0060-z |pages=25–60 [26–7] |s2cid=120199426}}</ref> <!-- The tradition of Chinese-Islamic astronomy survived -->

==Observatories==
[[File:Taqi al din.jpg|thumb|Work in the observatorium of [[Taqi al-Din Muhammad ibn Ma'ruf|Taqi al-Din]].]]

The first systematic observations in Islam are reported to have taken place under the patronage of al-Mamun. Here, and in many other private observatories from Damascus to Baghdad, [[meridian (geography)|meridian]] [[degree measurement]] were performed ([[al-Ma'mun's arc measurement]]), solar parameters were established, and detailed observations of the Sun, [[Moon]], and [[planets]] were undertaken.

During the 10th century, the [[Buwayhid]] dynasty encouraged the undertaking of extensive works in astronomy; such as the construction of a large-scale instruments with which observations were made in the year 950. This is known through recordings made in the zij of astronomers such as [[Ibn al-A'lam]]. The great astronomer [[Abd al-Rahman al-Sufi]] was patronised by prince [['Adud al-Dawla]], who systematically revised Ptolemy's catalogue of [[star]]s. [[Sharaf al-Dawla]] also established a similar observatory in Baghdad. Reports by Ibn Yunus and [[al-Zarqali]] in [[Toledo, Spain|Toledo]] and [[Córdoba, Spain|Cordoba]] indicate the use of sophisticated instruments for their time.

It was [[Malik Shah I]] who established the first large observatory, probably in [[Isfahan (city)|Isfahan]]. It was here where [[Omar Khayyám]] with many other collaborators constructed a zij and formulated the [[Iranian calendar|Persian Solar Calendar]] a.k.a. the ''jalali calendar''. A modern version of this calendar, the [[Solar Hijri calendar]], is still in official use in [[Iran]] and [[Afghanistan]] today.

The most influential observatory was however founded by [[Hulegu Khan]] during the 13th century. Here, [[Nasir al-Din al-Tusi]] supervised its technical construction at [[Maragha]]. The facility contained resting quarters for Hulagu Khan, as well as a library and mosque. Some of the top astronomers of the day gathered there, and from their collaboration resulted important modifications to the Ptolemaic system over a period of 50 years.

[[File:Samarkand-06.JPG|thumb|The [[Ulugh Beg Observatory]] in [[Samarkand]].]]

In 1420, prince [[Ulugh Beg]], himself an astronomer and mathematician, founded another large observatory in Samarkand, the remains of which were excavated in 1908 by Russian teams.

And finally, [[Taqi ad-Din Muhammad ibn Ma'ruf]] founded a [[Constantinople Observatory of Taqi ad-Din|large observatory]] in [[Ottoman Empire|Ottoman]] [[Constantinople]] in 1577, which was on the same scale as those in Maragha and Samarkand. The observatory was short-lived however, as opponents of the observatory and prognostication from the heavens prevailed and the observatory was destroyed in 1580.<ref name="HotW">[[John Roberts (historian)|John Morris Roberts]], ''The History of the World'', pp.&nbsp;264–74, [[Oxford University Press]], {{ISBN|978-0-19-521043-9}}</ref> While the Ottoman clergy did not object to the science of astronomy, the observatory was primarily being used for [[astrology]], which they did oppose, and successfully sought its destruction.<ref>{{cite journal |last=El-Rouayheb |first=Khaled |title=The Myth of "The Triumph of Fanaticism" in the Seventeenth-Century Ottoman Empire |journal=Die Welt des Islams |volume=48 |issue=2 |year=2008 |pages=196–221 |doi=10.1163/157006008X335930 }}</ref>

As observatory development continued, Islamicate scientists began to pioneer the planetarium. The major difference between a planetarium and an observatory is how the universe is projected. In an observatory, viewers look up into the night sky, on the other hand, planetariums allow for universes planets and stars to project at eye-level in a room. Scientist Ibn Firnas, created a planetarium in his home that included artificial storm noises and was completely made of glass.

==Instruments==

Our knowledge of the instruments used by Muslim astronomers primarily comes from two sources: first the remaining instruments in private and museum collections today, and second the treatises and manuscripts preserved from the Middle Ages.
Muslim astronomers of the "Golden Period" made many improvements to instruments already in use before their time, such as adding new scales or details.

===Celestial globes and armillary spheres===
[[File:A Large Persian Brass Celestial Globe with an ascription to Hadi Isfahani.jpg|thumb|A Large [[Iran|Persian]] Brass Celestial Globe with an ascription to Hadi Isfahani and a date of 1197 AH/ 1782–3 AD of typical spherical form, the globe engraved with markings, figures and astrological symbols, inscriptive details throughout]]
[[Celestial globe]]s were used primarily for solving problems in celestial astronomy. Today, 126 such instruments remain worldwide, the oldest from the 11th century. The altitude of the Sun, or the [[Right Ascension]] and [[Declination]] of stars could be calculated with these by inputting the location of the observer on the meridian ring of the globe.<ref>{{cite web |url=http://museodeco.com/t-prodReplogle.aspx#q9 |title=What is the purpose of the metal ring or semi-ring around some globes? |website=museodeco.com |access-date=27 April 2022 |archive-url=https://web.archive.org/web/20120402094254/http://museodeco.com/t-prodReplogle.aspx#q9 |archive-date=2 April 2012 |url-status=dead}}</ref> The initial blueprint for a portable celestial globe to measure celestial coordinates came from Spanish Muslim astronomer [[Jabir ibn Aflah]] (d. 1145). Another skillful Muslim astronomer working on celestial globes was [[Abd al-Rahman al-Sufi]] (b. 903), whose treatise the ''[[Book of Fixed Stars]]'' describes how to design the constellation images on the globe, as well as how to use the celestial globe. However, it was in Iraq in the 10th century that astronomer Al-Battani was working on celestial globes to record celestial data. This was different because up until then, the traditional use for a celestial globe was as an observational instrument. Al-Battani's treatise describes in detail the plotting coordinates for 1,022 stars, as well as how the stars should be marked. An armillary sphere had similar applications. No early Islamic armillary spheres survive, but several treatises on "the instrument with the rings" were written. In this context there is also an Islamic development, the spherical astrolabe, of which only one complete instrument, from the 14th century, has survived.

===Astrolabes===

Brass astrolabes were an invention of late antiquity. The first Islamic astronomer reported as having built an astrolabe is [[Muḥammad ibn Ibrāhīm al-Fazārī|Muhammad al-Fazari]] (late 8th century).<ref>[[Richard Nelson Frye]]: Golden Age of Persia. p. 163.</ref> Astrolabes were popular in the [[Islamic]] world during the "Golden Age", chiefly as an aid to finding the qibla. The earliest known example is dated to 927/8 (AH 315).<ref>{{cite web |url=http://www.soas.ac.uk/gallery/Previous/IslamicPatronage/19.html |title=An exhibition of Islamic art from the al-Sabah Collection |website=www.soas.ac.uk |access-date=27 April 2022 |archive-url=https://web.archive.org/web/20071031023004/http://www.soas.ac.uk/gallery/Previous/IslamicPatronage/19.html |archive-date=31 October 2007 |url-status=dead}}</ref>

The device was incredibly useful, and sometime during the 10th century it was brought to Europe from the Muslim world, where it inspired Latin scholars to take up an interest in both math and astronomy.<ref name="Astrolabes in Medieval Cultures">{{Citation |date=2018-12-18 |url=http://dx.doi.org/10.1163/9789004387867_002 |pages=1–2 |publisher=BRILL |doi=10.1163/9789004387867_002 |isbn=978-90-04-38786-7 |access-date=2020-12-13 |title=Astrolabes in Medieval Cultures|last1=Rodríguez-Arribas |first1=Josefina |last2=Burnett |first2=Charles |last3=Ackermann |first3=Silke |url-access=subscription }}</ref>{{Failed verification|date=July 2024}}

The largest function of the astrolabe is it serves as a portable model of space that can calculate the approximate location of any heavenly body found within the [[Solar System]] at any point in time, provided the latitude of the observer is accounted for. In order to adjust for latitude, astrolabes often had a second plate on top of the first, which the user could swap out to account for their correct latitude.<ref name="Astrolabes in Medieval Cultures"/> One of the most useful features of the device is that the projection created allows users to calculate and solve mathematical problems graphically which could otherwise be done only by using complex spherical trigonometry, allowing for earlier access to great mathematical feats.<ref>{{Citation |last=Brentjes |first=Sonja |chapter=Safavid Art, Science, and Courtly Education in the Seventeenth Century|date=2013-09-18|chapter-url=http://dx.doi.org/10.1007/978-3-642-36736-6_22 |title=From Alexandria, Through Baghdad |pages=487–502 |place=Berlin, Heidelberg |publisher=Springer Berlin Heidelberg |doi=10.1007/978-3-642-36736-6_22 |isbn=978-3-642-36735-9 |access-date=2020-12-13|chapter-url-access=subscription }}</ref> In addition to this, use of the astrolabe allowed for ships at sea to calculate their position given that the device is fixed upon a star with a known altitude. Standard astrolabes performed poorly on the ocean, as bumpy waters and aggressive winds made use difficult, so a new iteration of the device, known as a [[Mariner's astrolabe]], was developed to counteract the difficult conditions of the sea.<ref>{{Cite journal |last=Chilton |first=D. |date=January 1959 |title=Elizabethan Navigation – The Art of Navigation in England in Elizabethan and Early Stuart Times. Lieut.-Commander David W. Waters, R.N. 696 + xi pp., 87 plates, 43 diagrams. London (Hollis & Carter), 1958. 84s. net. |url=http://dx.doi.org/10.1017/s0373463300045987 |journal=Journal of Navigation |volume=12 |issue=1 |pages=109–111 |doi=10.1017/s0373463300045987 |bibcode=1959JNav...12..109C |s2cid=140551534 |issn=0373-4633|url-access=subscription }}</ref>

The instruments were used to read the time of the Sun rising and fixed stars. al-Zarqali of [[Andalusia]] constructed one such instrument in which, unlike its predecessors, did not depend on the latitude of the observer, and could be used anywhere. This instrument became known in Europe as the Saphea.<ref>{{cite web |url=http://astrolabes.org/pages/saphea.htm |title=The Saphea Arzachelis Universal Astrolabe |website=astrolabes.org |access-date=27 April 2022 |archive-url=https://web.archive.org/web/20111210101832/http://astrolabes.org/pages/saphea.htm |archive-date=10 December 2011 |url-status=dead}}</ref>
[[File:Khalili Collection Islamic Art sci 0161.5.jpg|thumb|Mid-17th century astrolabe inscribed with Quranic verses and Persian poetry as well as technical information, with five interchangeable plates corresponding to the latitudes of major cities]]
The astrolabe was arguably the most important instrument created and used for astronomical purposes in the medieval period. Its invention in early medieval times required immense study and much trial and error in order to find the right method of which to construct it to where it would work efficiently and consistently, and its invention led to several mathematic advances which came from the problems that arose from using the instrument.<ref name=":1">{{Cite journal |last=Berggren*|first=J. L. |date=December 1991 |title=Medieval Islamic Methods for Drawing Azimuth Circles on the Astrolabe |journal=Centaurus |volume=34 |issue=4 |pages=309–344 |doi=10.1111/j.1600-0498.1991.tb00864.x |bibcode=1991Cent...34..309B |issn=0008-8994}}</ref> The astrolabe's original purpose was to allow one to find the altitudes of the sun and many visible stars, during the day and night, respectively.<ref>{{Cite journal |last=Abbasi |first=Mubashir Ul-Haq |date=2014 |title=An Astrolabe by Muhammad Muqim of Lahore Dated 1047 AH (1637–38 CE) |journal=Islamic Studies|volume=53 |issue=1–2 |doi=10.52541/isiri.v53i1-2.178 }}</ref> However, they have ultimately come to provide great contribution to the progress of mapping the globe, thus resulting in further exploration of the sea, which then resulted in a series of positive events that allowed the world we know today to come to be.<ref name=":2">{{Cite journal |last=Castro |first=F |date=2015 |title=The Astrolabe Project |journal=Journal of Maritime Archaeology |volume=10 |issue=3 |pages=205–234 |doi=10.1007/s11457-015-9149-9 |bibcode=2015JMarA..10..205C |s2cid=162643992}}</ref> The astrolabe has served many purposes over time, and it has shown to be quite a key factor from medieval times to the present.

The astrolabe required the use of mathematics, and the development of the instrument incorporated azimuth circles, which opened a series of questions on further mathematical dilemmas.<ref name=":1" /> Astrolabes served the purpose of finding the altitude of the sun, which also meant that they provided one the ability to find the direction of Muslim prayer (or the direction of Mecca).<ref name=":1" /> Aside from these purposes, the astrolabe had a great influence on navigation, specifically in the marine world. This advancement made the calculation of latitude simpler, which led to an increase in sea exploration, and indirectly led to the Renaissance revolution, an increase in global trade activity, and ultimately the discovery of several of the world's continents.<ref name=":2" />

===Mechanical calendar===
Abu Rayhan Biruni designed an instrument he called "Box of the Moon", which was a [[Mechanical engineering|mechanical]] [[lunisolar calendar]], employing a [[gear train]] and eight [[gear]]-wheels.{{sfn|Hill|1991}} This was an early example of a fixed-[[wire]]d knowledge processing [[machine]].<ref name=Oren>Tuncer Oren (2001). "Advances in Computer and Information Sciences: From Abacus to Holonic Agents", ''Turk J Elec Engin'' '''9''' (1): 63–70 [64].</ref> This work of Al Biruni uses the same gear trains preserved in a 6th-century Byzantine portable sundial.<ref>"[http://hist.science.online.fr/antikythera/DOCS/FLORENCE2009/byzantine-sundial.htm A Byzantine Sundial-Calendar, reconstruction by M.T. Wright]"</ref>

===Sundials===
[[File:Timbuktu-manuscripts-astronomy-mathematics.jpg|thumb|The [[Timbuktu Manuscripts]] showing both [[mathematics]] and [[astronomy]].<ref>{{Cite web |url=http://www.saudiaramcoworld.com/issue/201105/from.africa.in.ajami.htm |title=Saudi Aramco World :From Africa, in Ajami |last=Verde |first=Tom |date=September 2011 |website=saudiaramcoworld.com |publisher=Aramco World |access-date=11 November 2016 |archive-url=https://web.archive.org/web/20141130201717/http://www.saudiaramcoworld.com/issue/201105/from.africa.in.ajami.htm |archive-date=2014-11-30 |url-status=dead}}</ref>]]

Muslims made several important improvements{{which|date=November 2016}} to the theory and construction of [[sundial]]s, which they inherited from their Indian and [[Roman Greece|Greek]] predecessors. [[Khwarizmi]] made tables for these instruments which considerably shortened the time needed to make specific calculations.

Sundials were frequently placed on mosques to determine the time of prayer. One of the most striking examples was built in the 14th century by the ''[[muwaqqit]]'' (timekeeper) of the Umayyad Mosque in Damascus, ibn al-Shatir.{{sfn|King|1996|pp=168{{ndash}}169}}

===Quadrants===

Several forms of [[Quadrant (instrument)|quadrants]] were invented by Muslims. Among them was the sine quadrant used for astronomical calculations, and various forms of the horary quadrant used to determine the time (especially the times of prayer) by observations of the Sun or stars. A center of the development of quadrants was 9th century Baghdad.{{sfn|King|1996|pp=167{{ndash}}168}} Abu Bakr ibn al-Sarah al-Hamawi (d. 1329) was a Syrian astronomer that invented a quadrant called “al-muqantarat al-yusra”. He devoted his time to writing several books on his accomplishments and advancements with quadrants and geometrical problems. His works on quadrants include ''Treatise on Operations with the Hidden Quadrant'' and ''Rare Pearls on Operations with the Circle for Finding Sines.'' These instruments could measure the altitude between a celestial object and the horizon. However, as Muslim astronomers used them, they began to find other ways to use them. For example, the mural quadrant, for recording the angles of planets and celestial bodies. Or the universal quadrant, for latitude solving astronomical problems. The horary quadrant, for finding the time of day with the sun. The almucantar quadrant, which was developed from the astrolabe.

=== Equatoria ===
Planetary [[equatorium|equatoria]] were probably made by ancient Greeks, although no findings nor descriptions have been preserved from that period. In his comment on Ptolemy's ''Handy Tables'', 4th century mathematician [[Theon of Alexandria]] introduced some diagrams to geometrically compute the position of the planets based on Ptolemy's epicyclical theory. The first description of the construction of a solar (as opposed to planetary) equatorium is contained in Proclus's 5th century work ''Hypotyposis'',<ref>{{Cite book |publisher=[[Teubner]] |last=Proclus |others=Karl Manitius (ed.) |title=Hypotyposis Astronomicarum Positionum |location=Leipzig |series=Bibliotheca scriptorum Graecorum et Romanorum Teubneriana |date=1909}}</ref> where he gives instructions on how to construct one in wood or bronze.<ref name="Evans">{{Cite book | publisher = [[Oxford University Press]] | isbn = 978-0-19-509539-5 | last = Evans | first = James | title = The History and Practice of Ancient Astronomy | location = Oxford & New York | date = 1998 | page = 404 }}</ref>

The earliest known description of a planetary equatorial is contained in early 11th century treatise by [[Ibn al-Samh]], preserved only as a 13th-century Castillian translation contained in the ''[[Libros del saber de astronomia]]'' (''Books of the knowledge of astronomy''); the same book contains also a 1080/1081 treatise on the equatorial by [[Al-Zarqali]].<ref name="Evans"/>

== Astronomy in Islamic art ==
Examples of cosmological imagery in Islamic art can be found in objects such as [[manuscript]]s, astrological tools, and palace [[fresco]]es, and the study of the heavens by Islamic astronomers has translated into artistic representations of the universe and astrological concepts.{{sfn|Nasr|1993|pp=75{{ndash}}77}} The Islamic world gleaned inspiration from Greek, Iranian, and Indian traditions to represent the stars and the universe.<ref name="Sar">{{cite web |last1=Sarda |first1=Marika |title=Astronomy and Astrology in the Medieval Islamic World |date=August 2011 |url=https://www.metmuseum.org/toah/hd/astr/hd_astr.htm |publisher=[[Metropolitan Museum of Art]] |access-date=5 November 2019}}</ref>

{{multiple image | direction = horizontal | total_width= 350 | header = | footer = | image1 = Rear of Bath Complex Qasr Amra Jordan1068.jpg | alt1 = | caption1 =The bath complex at [[Qasr Amra]], Jordan| image2 = Qasr Amra moz 5.jpg | alt2 =| caption2 = Detail of the Interior of the bath dome}}
The [[desert castle]] at [[Qasr Amra]], which was used as a [[Umayyad]] palace, has a bath dome decorated with the Islamic zodiac and other celestial designs.<ref name=":12">{{Cite book |title=Cosmos and Community In Early Medieval Art |last=Anderson |first=Benjamin |publisher=Yale University Press |year=2017 |location=New Haven and London |pages=63–69}}</ref>

The Islamic zodiac and astrological visuals can be seen in examples of metalwork. [[Pitcher (container)|Ewers]] depicting the twelve zodiac symbols exist in order to emphasize elite craftsmanship and carry blessings such as one example now at the Metropolitan Museum of Art.<ref>{{cite web |url=https://www.metmuseum.org/art/collection/search/444532 |title=Ewer base with Zodiac medallions |website=metmuseum.org |publisher=The Metropolitan Museum of Art |access-date=5 November 2019}}</ref> Coinage also carried zodiac imagery that bears the sole purpose of representing the month in which the coin was minted.<ref>{{Cite web |url=https://www.metmuseum.org/art/collection/search/444868 |title=Coin |website=www.metmuseum.org |access-date=2019-11-05}}</ref> As a result, astrological symbols could have been used as both decoration, and a means to communicate symbolic meanings or specific information.

==Notable astronomers==
{{More citations needed|date=March 2024}}
Some of the below are from Hill (1993), ''Islamic Science And Engineering'''.{{sfn|Hill|1993}}
{{Col-begin}}
{{Col-break}}
* [[Yaqūb ibn Tāriq]]
* [[Ibrahim al-Fazari]]
* [[Muhammad al-Fazari]]
* [[Mashallah ibn Athari]]
* [[Naubakht]]
* [[Abu Hanifa Dinawari]]
* [[Al-Khwarizmi]], also a mathematician
* [[Abu Ma'shar al-Balkhi]] (Albumasar)
* [[Al-Farghani]]
* [[Banū Mūsā]] (Ben Mousa)
** [[Ja'far Muhammad ibn Mūsā ibn Shākir]]
** [[Ahmad ibn Mūsā ibn Shākir]]
** [[Al-Hasan ibn Mūsā ibn Shākir]]
* [[Thābit ibn Qurra]] (Thebit)
** [[Sinan ibn Thabit]]
** [[Ibrahim ibn Sinan]]
* [[Sind ibn Ali]]
* [[Al-Majriti]]
* [[Al-Battani]] (Albatenius)
* [[Al-Farabi]] (Abunaser)
{{Col-break}}
* [[Abd Al-Rahman Al Sufi]]
* [[Abu Sa'id Gorgani]]
* [[Kushyar ibn Labban]]
* [[Abū Ja'far al-Khāzin]]
* [[Al-Mahani]]
* [[Habash al-Hasib al-Marwazi|Al-Marwazi]]
* [[Al-Nayrizi]]
* [[Al-Saghani]]
* [[Brethren of Purity]]
* [[Abū Sahl al-Qūhī]] (Kuhi)
* [[Abu-Mahmud al-Khujandi]]
* [[Abū al-Wafā' al-Būzjānī]]
* [[Ibn Yunus]]
* [[Abu Nasr Mansur]]
* [[Ibn al-Haytham]] (Alhacen)
* [[Al-Biruni]]
* [[Avicenna]]
* [[Abū Ishāq Ibrāhīm al-Zarqālī]] (Arzachel)
* [[Omar Khayyám]]
* [[Al-Khazini]]
* [[Ibn Bajjah]] (Avempace)
* [[Ibn Tufail]] (Abubacer)
{{Col-break}}
* [[Nur Ed-Din Al Betrugi]] (Alpetragius)
* [[Averroes]]
* [[Al-Jazari]]
* [[Anvari]]
* [[Sharaf al-Dīn al-Tūsī]]
* [[Mo'ayyeduddin Urdi]]
* [[Nasīr al-Dīn al-Tūsī|Nasir al-Din al-Tusi]]
* [[Ibn al-Nafis]]
* [[Qutb al-Din al-Shirazi]]
* [[Ibn al-Shatir]]
* [[Shams al-Dīn al-Samarqandī]]
* [[Jamshīd al-Kāshī]]
* [[Ulugh Beg]], also a mathematician
* [[Ali Qushji]], also a mathematician and philosopher
* [[Al-Birjandi]]
* [[Taqi al-Din Muhammad ibn Ma'ruf]], Ottoman astronomer
* [[Ahmad Nahavandi]]
* [[Ahmad Khani]]
* [[Haly Abenragel]]
* [[Abolfadl Harawi]]
{{Col-break}}
{{Col-end}}

==See also==
* [[Astrology in the medieval Islamic world]]
* [[History of astronomy]]

== References ==
{{Reflist|32em}}

== Sources ==
*{{cite book |last1=Dallal |first1=Ahmad |editor1-last=Esposito |editor1-first=John |title=The Oxford History of Islam |date=1999 |publisher=[[Oxford University Press]] |location=New York |isbn=978-01951-0-799-9 |page=|url-access=registration |url=https://archive.org/details/oxfordhistoryofi00john/page/n5/mode/2up |chapter=Science, Medicine and Technology}}
* {{cite book |last1=Dallal |first1=Ahmad |author1-link=Ahmad S. Dallal |title=Islam, Science, and the Challenge of History |date=2010 |publisher=[[Yale University Press]] |isbn=978-0-300-15911-0 |page=|url-access=registration |url=https://archive.org/details/islamsciencechal0000dall}}
* {{Citation |last=Hill |first=Donald R. |author-link=Donald Routledge Hill |title=Mechanical Engineering in the Medieval Near East |journal=Scientific American |volume=264 |issue=5 |date=May 1991 |pages=64–69|bibcode=1991SciAm.264e.100H |doi=10.1038/scientificamerican0591-100 }} 
* {{cite book |last=Hill |first=Donald R. |author-link=Donald Routledge Hill |title=Islamic Science And Engineering |publisher=[[Edinburgh University Press]] |year=1993 |isbn=978-0-7486-0455-5 |url=https://archive.org/details/islamicscienceen0000hill/page/n3/mode/2up |url-access=registration}}
* {{cite book |last1=Hoskin |first1=Michael |title=The Cambridge Concise History of Astronomy |date=1999 |publisher=[[Cambridge University Press]] |location=Cambridge |isbn=978-0-521-57600-0 |url=https://books.google.com/books?id=9gZLXocOnSgC}}
* {{cite book |first=Toby |last=Huff |author-link=Toby Huff |year=1993|title=The Rise of Early Modern Science: Islam, China, and the West |publisher=[[Cambridge University Press]]
 |isbn=978-0-521-52994-5 |url=https://archive.org/details/riseofearlymoder0000huff |url-access=registration}}
* {{cite journal|last=Janos|first=Damien|title=Al-Fārābī on the Method of Astronomy|journal=[[Early Science and Medicine]]|year=2010|url=http://www.jstor.org/stable/20750216|volume=Early Science and Medicine 15, no. 3 (2010)|issue=3|pages=237–65|doi=10.1163/157338210X493941|jstor=20750216 |issn=	1383-7427|url-access=subscription}}
* {{cite book |last=King |first=David A. |author-link=David A. King (historian) |year=1996 |chapter=Islamic Astronomy |title=Astronomy before the Telescope |editor-first=Christopher |editor-last=Walker |publisher=[[British Museum]]  |pages=143{{ndash}}174 |isbn=978-0-7141-2733-0 |editor-link=Christopher J. Walker |url=https://archive.org/details/astronomy-before-the-telescope-c.-b.-f.-walker/page/n7/mode/2up}}
* {{cite book |last1=King |first1=David A. |author1-link=David A. King (historian) |title=In Synchrony with the Heavens, Studies in Astronomical Timekeeping and Instrumentation in Medieval Islamic Civilization: The Call of the Muezzin |date=2005 |publisher=[[Brill Publishers]] |isbn=978-90-04-14188-9 |page=|volume=1}}
* {{cite book |last=Nasr |first=Seyyed H. |author-link=Hossein Nasr|date=1993 |orig-year=1964 |title=An Introduction to Islamic Cosmological Doctrines |edition=2nd |publisher=[[State University of New York Press]] |isbn=978-0-7914-1515-3 |url=https://archive.org/details/introductiontois00nasr/page/n5/mode/2up |url-access=registration }}
* {{cite journal |last=Ragep |first=F. Jamil |year=2001b |title=Freeing Astronomy from Philosophy: An Aspect of Islamic Influence on Science |journal=[[Osiris (journal)|Osiris]] |series=2nd  |volume=16 |issue= |pages=49{{ndash}}71 |bibcode = 2001Osir...16...49R |doi=10.1086/649338|s2cid=142586786 |url=http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=156332 }}
* {{cite journal |last=Sabra |first=A. I. |author-link=A. I. Sabra |year=1998 |title=Configuring the Universe: Aporetic, Problem Solving, and Kinematic Modeling as Themes of Arabic Astronomy |journal=[[Perspectives on Science]] |volume=6 |issue=3 |pages=288{{ndash}}330 |doi=10.1162/posc_a_00552 |s2cid=117426616 }}
* {{cite book |editor1-last=Sachau |editor1-first=Edward |editor1-link=Edward Sachau |title=Alberuni's India: An Account of the Religion, Philosophy, Literature, Geography, Chronology, Astronomy, Customs, Laws and Astrology of India about A.D. 1030 |date=1910 |publisher=Kegan Paul, Trench, Trübner |location=London |page=|volume=1 |url=http://www.columbia.edu/cu/lweb/digital/collections/cul/texts/ldpd_5949073_001/}}
* {{cite journal |last=Saliba |first=George |date=September 1993 |title=Al-Qushjī's Reform of the Ptolemaic Model for Mercury |url=http://dx.doi.org/10.1017/s0957423900001776 |journal=[[Arabic Sciences and Philosophy]] |volume=3 |issue=2 |pages=161–203 |doi=10.1017/s0957423900001776 |s2cid=170118014 |issn=0957-4239|url-access=subscription }}
* {{cite encyclopedia |editor=Thomas Hockey |last=Samsó |first=Julio |title=Biṭrūjī: Nūr al-Dīn Abū Isḥāq &#91;Abū Jaʿfar&#93; Ibrāhīm ibn Yūsuf al-Biṭrūjī |encyclopedia=The Biographical Encyclopedia of Astronomers |publisher=Springer |year=2007 |location=New York |pages=133{{ndash}}134 |url=http://islamsci.mcgill.ca/RASI/BEA/Bitruji_BEA.htm |isbn=978-0-387-31022-0 |display-editors=etal}} ([http://islamsci.mcgill.ca/RASI/BEA/Bitruji_BEA.pdf PDF version])
* {{cite encyclopedia |last=Samsó |first=Julio |title=Al-Bitruji Al-Ishbili, Abu Ishaq |encyclopedia=[[Dictionary of Scientific Biography]] |publisher=Charles Scribner's Sons |location=New York |year=1980 |isbn=978-0-684-10114-9 |url=http://www.encyclopedia.com/doc/1G2-2830904829.html }}
* {{cite book |last=Sidoli|first=Nathan|title=Mathematical Methods in Ptolemy's Analemma. In Ptolemy's Science of the Stars in the Middle Ages. Ptolemaeus Arabus et Latinus|year=2020 |url=https://doi.org/10.1484/M.PALS-EB.5.120173|volume=Studies 1. Brepols Publishers.|pages=1:35–77|doi=10.1484/M.PALS-EB.5.120173|s2cid=242599669}}

===Further reading===
* {{Citation
 |last=Ajram
 |first=K.
 |year=1992
 |title=Miracle of Islamic Science
 |chapter=Appendix B
 |publisher=Knowledge House Publishers
 |isbn=978-0-911119-43-5 |ref=none
}}
* {{cite book |last=Kennedy |first=Edward S. |year=1998 |title=Astronomy and Astrology in the Medieval Islamic World |publisher=Brookfield, VT: Ashgate |isbn=978-0-86078-682-5 |ref=none}}
* {{Citation |last=Gill
 |first=M.
 |year=2005
 |title=Was Muslim Astronomy the Harbinger of Copernicanism?
 |url=http://www.chowk.com/articles/9489
 |access-date=2008-01-22
 |archive-url=https://web.archive.org/web/20080102034220/http://www.chowk.com/articles/9489
 |archive-date=2 January 2008
 |url-status=dead |ref=none
}}
* {{cite journal |last1=Gingerich |first1=Owen |author1-link=Owen Gingerich |title=Islamic astronomy |journal=[[Scientific American]] |date=1986 |volume=254 |issue=10 |page=74 |doi=10.1038/scientificamerican0486-74 |url=http://faculty.kfupm.edu.sa/PHYS/alshukri/PHYS215/Islamic_astronomy.htm |bibcode=1986SciAm.254d..74G |ref=none|url-access=subscription }}
* {{Citation
 |last=Hassan
 |first=Ahmad Y.
 |author-link=Ahmad Y Hassan
 |url=http://www.history-science-technology.com/Articles/articles%2071.htm
 |title=Transfer Of Islamic Technology To The West, Part II: Transmission Of Islamic Engineering
 |access-date=2008-01-22
 |archive-url=https://web.archive.org/web/20080218171021/http://www.history-science-technology.com/Articles/articles%2071.htm
 |archive-date=18 February 2008
 |url-status=dead |ref=none
}}
* {{Citation
 |last=King
 |first=David A.
 |year=1983
 |title=The Astronomy of the Mamluks
 |journal=[[Isis (journal)|Isis]]
 |volume=74
 |issue=4
 |pages=531–555
 |doi=10.1086/353360
|s2cid=144315162 |ref=none
 }}
* {{Citation
 |last=King
 |first=David A.
 |year=1986
 |title=Islamic mathematical astronomy
 |publisher=[[London]]
 |isbn=978-0-86078-407-4 |ref=none
}}
* {{Citation
 |last=King
 |first=David A. |author-link=David A. King (historian)
 |year=2005
 |title=In Synchrony with the Heavens, Studies in Astronomical Timekeeping and Instrumentation in Medieval Islamic Civilization
 |publisher=[[Brill Publishers]]
 |isbn=978-90-04-14188-9 |ref=none |volume=2: Instruments of Mass Calculation
}}
* Lindberg, D.C., and M. H. Shank, eds. ''The Cambridge History of Science. Volume 2: Medieval Science'' (Cambridge UP, 2013), chapter 4 covers astronomy in Islam.
* {{Citation
 |last1=Rashed
 |first1=Roshdi
 |last2=Morelon
 |first2=Régis
 |year=1996
 |title=Encyclopedia of the History of Arabic Science
 |series=1
 |volume=& 3
 |publisher=[[Routledge]]
 |isbn=978-0-415-12410-2
|title-link=Encyclopedia of the History of Arabic Science |ref=none
 }}
* {{Citation
 |last=Saliba
 |first=George
 |author-link=George Saliba
 |year=1994a
 |title=Early Arabic Critique of Ptolemaic Cosmology: A Ninth-Century Text on the Motion of the Celestial Spheres
 |journal=Journal for the History of Astronomy
 |volume=25
 |issue=2
 |pages=115–141
|bibcode = 1994JHA....25..115S |doi=10.1177/002182869402500205
 |s2cid=122647517 |ref=none
 }}
* {{cite book |last=Saliba |first=George |author-link=George Saliba |year=1994b |title=A History of Arabic Astronomy: Planetary Theories During the Golden Age of Islam |publisher=[[New York University Press]] |isbn=978-0-8147-8023-7|url=https://archive.org/details/historyofarabica0000sali/page/n3/mode/2up |url-access=registration |ref=none}}
* {{cite web |last=Saliba |first=George |author-link=George Saliba |year=1999 |url=http://www.columbia.edu/~gas1/project/visions/case1/sci.1.html |title=Whose Science is Arabic Science in Renaissance Europe? |publisher=[[Columbia University]] |access-date=2008-01-22 |ref=none}}
* {{Citation
 |last=Saliba
 |first=George
 |author-link=George Saliba
 |year=2000
 |title=Arabic versus Greek Astronomy: A Debate over the Foundations of Science
 |journal=Perspectives on Science
 |volume=8
 |issue=4
 |pages=328–341
 |doi=10.1162/106361400753373713
|s2cid=57562913 |ref=none
 }}

==External links==
{{commons category}}
* [https://web.archive.org/web/20051218025632/http://faculty.kfupm.edu.sa/phys/alshukri/PHYS215/Islamic%20astronomy.htm ''Scientific American'' article on Islamic Astronomy] (archived 18 December 2005)
* [http://www.auass.com/ The Arab Union for Astronomy and Space Sciences (AUASS)]
* [https://web.archive.org/web/20070707114137/http://www.kacst.edu.sa/eng/inst/agri/dept4.php King Abdul Aziz Observatory] (archived 7 July 2007)
* [http://www.hps.cam.ac.uk/starry/isaslabecalen.html History of Islamic Astrolabes]. {{Webarchive|url=https://web.archive.org/web/20160812175641/http://www.hps.cam.ac.uk/starry/isaslabecalen.html |date=2016-08-12 }}.
* [http://www.ianridpath.com/startales/alsufi.htm Al-Sufi's constellations]

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{{Islamic studies}}

[[Category:Medieval astronomy]]
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