Banū Mūsā

The Banū Mūsā brothers ("Sons of Moses"), namely Abū Jaʿfar Muḥammad ibn Mūsā ibn Shākir (before 803 – 873), Abū al‐Qāsim Aḥmad ibn Mūsā ibn Shākir (803 – 873) and Al-Ḥasan ibn Mūsā ibn Shākir (810 – 873), were three 9th-century Persian scholars of Baghdad who are known for their Book of Ingenious Devices on automata (automatic machines) and mechanical devices. Another important work of theirs is the Book on the Measurement of Plane and Spherical Figures, a foundational work on geometry that was frequently quoted by both Islamic and European mathematicians.^[1]

The Banu Musa also worked in astronomical observations established in Baghdad by the Abbasid Caliph al-Ma'mun. They also participated in an 9th-century expedition to make geodesic measurements to determine the length of a degree.^[1]

Contents 1 Early life 2 Works 2.1 Automata 2.2 Astronomy 2.3 Mathematics 3 See also 4 Notes 5 References 6 Further reading 7 External links

Early life

The Banu Musa were sons of Mūsā ibn Shākir, who had been a highwayman and later an astrologer and astronomer to the Caliph al-Maʾmūn. After his death, his young sons were looked after by the court of al-Maʾmūn.^[2]

The brothers were given access to the famous House of Wisdom library and translation center in Baghdad. They participated in the efforts to translate ancient Greek works into Arabic by sending for Greek texts from the Byzantines, paying large sums for their translation, and learning Greek themselves.^[2] On such trips, Abu Ja'far met and recruited the famous mathematician and translator Thabit ibn Qurra. At some point Hunayn Ibn Ishaq was also part of their team.^[1]

Works

The Banu Musa wrote almost 20 books many of which are now lost.^[1]

Automata

Most notable among their achievements is their work in the field of automation, which they utilized in toys and other entertaining creations. They have shown important advances over those of their Greek predecessors.^[1] Their Book of Ingenious Devices describes 100 such inventions; the ones which have been reconstructed work as designed. While designed primarily for amusement purposes, they employ innovative engineering technologies such as one-way and two-way valves able to open and close by themselves, mechanical memories, devices to respond to feedback, and delays. Most of these devices were operated by water pressure.^[2]

Astronomy

• On the Visibility of the Crescent, by Muhammad.

• Book on the Beginning of the World, by Muhammad.

• Book on the Motion of Celestial Spheres (Kitāb Ḥarakāt al‐aflāk), by Muhammad.

• Book of Astronomy (Kitāb al‐Hayʾa), by Muhammad.

• Book on the First Motion of the Celestial Sphere (Kitāb Ḥarakāt al‐falak al‐ūlā), containing a critique of the Ptolemaic system. Muhammad in this book denied the existence of the Ptolemaic 9th sphere which Ptolemy thought was responsible for the motion.^[1]

• A book of zij, by Ahmad

• Another book of zij, listed under the Banu Musa, mentioned by Ibn Yunus.^[1]

• A translation of a Chinese work called A Book of Degrees on the Nature of Zodiacal Signs.

• Book on The Construction of the Astrolabe, quoted by al-Biruni.^[1]

• Book on the Solar Year, was traditionally attributed to Thabit ibn Qurra, but recent research has shown that it was actually by the Bani Musa.^[1]

Mathematics

• Book on the Measurement of Plane and Spherical Figures, later edited by Naṣīr al‐Dīn al‐Ṭūsī in the 13th century. A Latin translation by Gerard of Cremona appeared the 12th century under the titles Liber trium fratrum de geometria and Verba filiorum Moysi filii Sekir. This treatise on geometry was used extensively in in the Middle Ages, quoted by authors such as Thābit ibn Qurra, Ibn al‐Haytham, Leonardo Fibonacci, Jordanus de Nemore, and Roger Bacon.^[1]

• Book on the Mathematical Proof by Geometry That There Is Not a Ninth Sphere Outside the Sphere of the Fixed Stars, by Ahmad.

• A treatise containing a discussion between Ahmad and Sanad ibn ʿAli.

• Conic Sections of Apollonius of Perga

• Book on a Geometric Proposition Proved by Galen

• Reasoning on the Trisection of an Angle, by Aḥmad,

• Book on an Oblong Round Figure, which contains a description of procedure used to draw an ellipse using a string, now called the gardener's construction.^[1]

See also

• Their book, Book of Ingenious Devices.
• Nuʿaym ibn Muḥammad ibn Mūsā, the son of Abu Ja'far Muhammad, wrote a mathematical treatise.
• Inventions in the Muslim world
• Islamic Golden Age
• Islamic science

Notes

References

• Casulleras, Josep (2007). "Banū Mūsā". In Thomas Hockey et al. The Biographical Encyclopedia of Astronomers. New York: Springer. pp. 92–4. ISBN 9780387310220. http://islamsci.mcgill.ca/RASI/BEA/Banu_Musa_BEA.htm.  (PDF version)
• Masood, Ehsad (2009). Science and Islam A History. Icon Books Ltd. pp. 161–163. 

Further reading

• Rashed, Roshdi (1996). Les Mathématiques Infinitésimales du IXe au XIe Siècle 1: Fondateurs et commentateurs: Banū Mūsā, Ibn Qurra, Ibn Sīnān, al-Khāzin, al-Qūhī, Ibn al-Samḥ, Ibn Hūd. London  Reviews: Seyyed Hossein Nasr (1998) in Isis 89 (1) pp. 112–113; Charles Burnett (1998) in Bulletin of the School of Oriental and African Studies, University of London 61 (2) p. 406.
• D El-Dabbah, The geometrical treatise of the ninth-century Baghdad mathematicians Banu Musa (Russian), in History Methodology Natur. Sci., No. V, Math. Izdat. (Moscow, 1966), pp. 131–139.
• Ramon Guardans, A Brief Note on the anwā' Texts of the Late Tenth Century, in: Variantology 4. On Deep Time Relations of Arts, Sciences and Technologies In the Arabic-Islamic World and Beyond, ed. by Siegfried Zielinski and Eckhard Fürlus in cooperation with Daniel Irrgang and Franziska Latell (Cologne: Verlag der Buchhandlung Walther König, 2010), pp. 177–193. [1]
• Claus-Peter Haase, Modest Variations — Theoretical Tradition and Practical Innovation in the Mechanical Arts from Antiquity to the Arab Middle Ages, in: Variantology 4. On Deep Time Relations of Arts, Sciences and Technologies In the Arabic-Islamic World and Beyond, ed. by Siegfried Zielinski and Eckhard Fürlus in cooperation with Daniel Irrgang and Franziska Latell (Cologne: Verlag der Buchhandlung Walther König, 2010), pp. 195–213. [2]

External links

• al-Darrbagh, J. (2008) [1970–80]. "Banū Mūsā". Complete Dictionary of Scientific Biography. Encyclopedia.com. http://www.encyclopedia.com/doc/1G2-2830900258.html. 
• O'Connor, John J.; Robertson, Edmund F., "Banu Musa brothers", MacTutor History of Mathematics archive, University of St Andrews, http://www-history.mcs.st-andrews.ac.uk/Biographies/Banu_Musa.html .
• O'Connor, John J.; Robertson, Edmund F., "Ahmad Banu Musa", MacTutor History of Mathematics archive, University of St Andrews, http://www-history.mcs.st-andrews.ac.uk/Biographies/Banu_Musa_Ahmad.html .
• O'Connor, John J.; Robertson, Edmund F., "al-Hasan Banu Musa", MacTutor History of Mathematics archive, University of St Andrews, http://www-history.mcs.st-andrews.ac.uk/Biographies/Banu_Musa_al-Hasan.html .

Astronomy in medieval Islam Astronomers 8th century Ahmad Nahavandi Al-Fadl ibn Naubakht Ibrāhīm al-Fazārī and his son Mashallah ibn Athari 9th century Abu Ma'shar al-Balkhi Abu Said Gorgani Al-Farghānī Al-Kindi Al-Mahani Al-Ḥajjāj ibn Yūsuf ibn Maṭar Al-Marwazi 'Ali ibn 'Isa al-Asturlabi Banu Musa Brothers Iranshahri Khālid ibn ʿAbd al‐Malik Al-Khwārizmī Sahl ibn Bishr Thābit ibn Qurra Yaʿqūb ibn Ṭāriq 10th century Abd al-Rahman al-Sufi Abu-Mahmud Khojandi Abū Ja'far al-Khāzin Abū Sahl al-Qūhī Abū al-Wafā' Būzjānī Ahmad ibn Yusuf Al-Battani Alchabitius Al-Nayrizi Al-Saghani Ibn Yunus Ibrahim ibn Sinan 11th century Abu Nasr Mansur Al-Bīrūnī Al-Zarqālī Alhazen Avicenna Ibn al-Saffar Kushyar ibn Labban Said Al-Andalusi Sijzi 12th century Al-Bitruji Al-Kharaqī Al-Khazini Al-Samaw'al Anvari Ibn al-Kammad Jabir ibn Aflah Omar Khayyám Sharaf al-Dīn al-Ṭūsī 13th century Ibn al-Banna' al-Marrakushi Ibn al‐Ha'im al‐Ishbili Jamal ad-Din Muhyi al-Dīn al-Maghribī Nasir al-Din al-Tusi Qotb al-Din Shirazi Shams al-Dīn al-Samarqandī Zakariya al-Qazwini Ibn Abi al-Shukr Mu'ayyad al-Din al-'Urdi 14th century Ibn al-Shatir Kamāl al-Dīn Fārisī Shams al-Dīn Abū Abd Allāh al-Khalīlī 15th century Ali Qushji Jamshīd al-Kāshī Qāḍī Zāda al-Rūmī Ulugh Beg Sibt al-Mardini 16th century Al-Birjandi Bahāʾ al-dīn al-ʿĀmilī Piri Reis Taqi al-Din Muhammad ibn Ma'ruf Works ʿAjā'ib al-makhlūqāt wa gharā'ib al-mawjūdāt Arabic star names Book of Optics Encyclopedia of the Brethren of Purity Islamic calendar Star chart Tabula Rogeriana The Book of Healing Zij: Alfonsine tables Almanac Astronomical catalog Book of Fixed Stars Star catalogue Toledan Tables Trigonometry table Zij-i Ilkhani Zij-i-Sultani Instruments Alidade Analog computer Aperture Armillary sphere Astrolabe Astronomical clock Celestial globe Compass Compass rose Dioptra Equatorial ring Equatorium Globe Graph paper Magnifying glass Mural instrument Navigational astrolabe Nebula Planisphere Quadrant Sextant Shadow square Spherical astrolabe Sundial Telescope Triquetrum Concepts Almucantar Apogee Astrophysics Axial tilt Azimuth Celestial mechanics Celestial spheres Circular orbit Deferent and epicycle Earth's rotation Eccentricity Ecliptic Elliptic orbit Equant Galaxy Geocentrism Gravitational potential energy Gravity Heliocentrism Inertia Islamic cosmology Moonlight Multiverse Muslim views on astrology Obliquity Parallax Precession Qibla Salat times Specific gravity Spherical Earth Starlight Sublunary sphere Sunlight Supernova Temporal finitism Trepidation Triangulation Tusi-couple Universe Centers Al-Azhar University House of Knowledge House of Wisdom Islamic observatories Istanbul observatory of Taqi al-Din Madrasah Maragheh observatory Observatory Research institute Samarkand observatory Umayyad Mosque University of Al-Karaouine Influences Babylonian astronomy Egyptian astronomy Hellenistic astronomy Indian astronomy Influenced Byzantine astronomy Chinese astronomy European astronomy Indian astronomy

Mathematics in medieval Islam Mathematicians 9th century 'Abd al-Hamīd ibn Turk · Sind ibn Ali · Al-Abbās ibn Said al-Jawharī · Al-Ḥajjāj ibn Yūsuf ibn Maṭar · Al-Kindi · Al-Mahani · Banū Mūsā · Hunayn ibn Ishaq · Muḥammad ibn Mūsā al-Khwārizmī · Thābit ibn Qurra · Na'im ibn Musa · Sahl ibn Bishr · Habash al-Hasib al-Marwazi 10th century Abd al-Rahman al-Sufi · Abū al-Wafā' al-Būzjānī · Abū Ja'far al-Khāzin · Abū Kāmil Shujāʿ ibn Aslam · Abu'l-Hasan al-Uqlidisi · Abu-Mahmud Khojandi · Ahmad ibn Yusuf · Al-Nayrizi · Al-Saghani · Brethren of Purity · Ibn Sahl · Ibn Yunus · Ibrahim ibn Sinan · Muhammad ibn Jābir al-Harrānī al-Battānī · Sinan ibn Thabit · Al-Isfahani · Abu-Mahmud Khojandi · Nazif ibn Yumn · Abū Sahl al-Qūhī 11th century Abū Ishāq Ibrāhīm al-Zarqālī · Abu Nasr Mansur · Abū Rayḥān al-Bīrūnī · Alhazen · Ibn Muʿādh al-Jayyānī · Al-Karaji · Al-Sijzi · Alī ibn Ahmad al-Nasawī · Avicenna · Ibn Tahir al-Baghdadi · Kushyar ibn Labban · Yusuf al-Mu'taman ibn Hud 12th century Al-Khazini · Ibn Yahyā al-Maghribī al-Samaw'al · Omar Khayyám · Jabir ibn Aflah 13th century Muhyi al-Dīn al-Maghribī · Nasīr al-Dīn al-Tūsī · Shams al-Dīn al-Samarqandī · Sharaf al-Dīn al-Tūsī · Ibn al‐Ha'im al‐Ishbili · Ibn Abi al-Shukr 14th century Yaʿīsh ibn Ibrāhīm al-Umawī · Ibn al-Banna' al-Marrakushi · Ibn al-Shatir · Kamāl al-Dīn Fārisī · Al-Khalili · Qotb al-Din Shirazi · Ahmad al-Qalqashandi 15th century Abū al-Ḥasan ibn ʿAlī al-Qalaṣādī · Ali Qushji · Jamshīd al-Kāshī · Qāḍī Zāda al-Rūmī · Ulugh Beg · 16th century Al-Birjandi · Muhammad Baqir Yazdi · Taqi al-Din · Ibn Hamza al-Maghribi · Ibn Ghazi al-Miknasi Treatises Almanac · Book of Fixed Stars · Book of Optics · De Gradibus · Encyclopedia of the Brethren of Purity · Tables of Toledo · Tabula Rogeriana · The Compendious Book on Calculation by Completion and Balancing · The Book of Healing · Zij · Zij-i Ilkhani · Zij-i-Sultani Concepts Alhazen's problem Centers Al-Azhar University · Al-Mustansiriya University · House of Knowledge · House of Wisdom · Istanbul observatory of Taqi al-Din · Madrasah · Maktab · Maragheh observatory · University of Al-Karaouine Influences Babylonian mathematics · Greek mathematics · Indian mathematics Influenced Byzantine mathematics · European mathematics · Indian mathematics

Persondata
Name	Musa, Banu
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Date of death	873
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