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Edited by  H. B. Paksoy

Table of Contents:

H. B. Paksoy "Ibadinov's Kuyas Ham Alav"
Peter B. Golden (Rutgers) "Codex Comanicus"
Richard Frye (Harvard) "Narshaki's The History of Bukhara"
Robert Dankoff (Chicago) "Adab Literature"
Uli Schamiloglu (Wisconsin-Madison) "Umdet ul Ahbar"
Kevin Krisciunas (Joint Astronomy Centre) "Ulug Beg's Zij"
Audrey Altstadt (UMass-Amherst) "Bakikhanli's Nasihatlar"
Edward J. Lazzerini (New Orleans) "Gaspirali's Tercuman"
David S. Thomas (Rhode Island) "Akcura's Uc Tarz-i Siyaset"

ISBN: 975-428-033-9
Library of Congress Card Catalog: DS329.4 .C46 1992
173 Pp. (paperback)  US$20 

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Please refer to the printed version for the footnotes

The Legacy of Ulugh Beg       
Kevin Krisciunas[1]       

          Muhammed Taragai Ulugh Beg (1394-1449) was a Turk who
ruled the province of Transoxiana (Maverannahr), a region
situated between the River Oxus (Amu Darya) and the River
Jaxartes (Syr Darya), the principal city of which was Samarkand.
Ulugh Beg's grandfather was the famous conqueror Timur
(1336-1405).  Ulugh Beg became the ruler of Transoxiana in 1447
upon the death of hisfather.  But his rule was of short duration. 
Two years later he was killed by an assassin hired by his son
'Abd al Latif.      
          Were it only for his role as prince, viceroy, and
martyr, few scholars would know of Ulugh Beg.  But his memory
lives on because he was an observatory builder, patron of
astronomy, and astronomer in his own right.  He was certainly the
most important observational astronomer of the 15th century.  He
was one of the first to advocate and build permanently mounted
astronomical instruments.  His catalogue of 1018 stars (some
sources count 1022) was the only such undertaking carried out
between the timesof Claudius Ptolemy (ca. 170 A.D.) and Tycho
Brahe (ca. 1600).  And, as we shall briefly discuss here, his
attitude towards scientific endeavors was surprisingly modern.    
 The administration of Transoxiana was the responsibility of
Ulugh Beg's father for most of Ulugh Beg's life.  The prince had
the opportunity (and the inclination) to pursue scholarly
matters.  His interest in astronomy dates from an early age,
whenhe visited the remains of the Maragha Observatory, made
famous bythe astronomer Nasir al-Din al-Tusi (1201-74). The
principal accomplishment at Maragha was the Zij-i ilkhani, or
Ilkhanic Tables.[2]      
          A principal source of our information about the
astronomicalactivity at Samarkand is a letter of one Ghiyath
al-Din Jamshid al-Kashi (d. 1429), which is available in Turkish
and English (see Sayili 1960).  This letter, originally in
Persian, was written in 1421 or 1422.  From it we deduce that
serious astronomical activity began in Samarkand in 1408-10, and
that theconstruction of Ulugh Beg's observatory was begun in
1420.  Amongthe astronomers known to have been active at
Samarkand, we know only a few by name, but according to al-Kashi
there were sixty orseventy scholars at the madrasa who were well
enough versed in mathematics to participate in some capacity in
the astronomical observations and/or seminars.
       The observations were carried out systematically from 1420
to 1437.  While observatories today are expected to carry on
indefinitely, this was not the case in olden times. Rather,
observations were carried out, for example, to update tables of
planetary motions in order to predict their future positions. 
al-Kashi tells us (see Sayili 1960, p.106):            
As to the inquiry of those who ask why observations are  not
completed in one year but require ten or fifteen  years, the
situation is such that there are certain  conditions suited to
the determination of matters  pertaining to the planets, and it
is necessary to  observe them when these conditions obtain.  It
is  necessary, e.g., to have two eclipses in both of which  the
eclipsed parts are equal and to the same side, and  both these
eclipses have to take place near the same  node.  Likewise,
another pair of eclipses conforming to  other specifications is
needed, and still other cases  of a similar nature are required. 
It is necessary to  observe Mercury at a time when it is at its
maximum  morning elongation and once at its maximum evening 
elongation, with the addition of certain other  conditions, and a
similar situation exists for the  other planets.    Now, all
these circumstances do not obtain within  a single year, so that
observations cannot be made in  one year.  It is necessary to
wait until the required  circumstances obtain and then if there
is cloud at the  awaited time, the opportunity will be lost and
gone for  another year or two until the like of it occurs once 
more.  In this manner there is need for ten or fifteen  years.   
One might add that because it takes Saturn 29 years to return to
the same position amongst the stars (that being its period of
revolution about the Sun), a period of 29 years might have been
the projected length of the Samarkand program of observations.  
A number of instruments were used for the observations of the
planets and for determining the relative positions of the
stars.[3]  The largest instrument in Samarkand was the so-
calledFakhri sextant.  It was a 60-degree stone arc mounted on
the north-south meridian line.  Such an instrument was used to
determine the transit altitudes of stars (i.e. their maximum
angular distances above the horizon).  From the most southern
andnorthern positions of the Sun, observed over the course of a
year, one can easily determine the obliquity of the ecliptic
(i.e. the tilt of the Earth's axis of rotation with respect to
the plane of its orbit.)  The mean of these extrema, or the
meridian altitude of the Sun at the moment of the vernal or
autumnal equinox allows one (by definition) to determine one's
latitude.[4]  According to Ulugh Beg the obliquity of the
ecliptic was 23 degrees 30' 17" (differing by only 32" from the
true value for his time).  His value for the latitude of
Samarkand was 39 degrees 37' 33".  Now, to the reader
unaccustomed to astronomical topics, these might seem like just
numbers, the accuracy of which may mean nothing.  The most
interesting thing about the Fakhri sextant in Samarkand was that
its radius was 40 meters! (This is very nearly equal to the
height of the dome of the 200-inch reflector at Palomar Mountain,
California.)  The Fakhri sextant was by far the largest meridian
instrument ever built.  It could achieve a resolution of a
several seconds of arc -- on the order of a six-hundredth of a
degree, or the diameter of an American penny at a distance of
more than half a kilometer.  Because the Fakhri sextant was an
arc fixed on the meridian,it could only be used for determining
the declinations of celestial bodies.  (This being before the
invention of accurate clocks, it could not be used for the
determinations of relative right ascensions.)  Because it was a
60-degree arc, it could not be used to observe stars along the
full north-south meridian.  Thus, it could not be used, say, to
determine the angular separations of pairs of stars, or for
observing stars near the northern or southern horizons. 
Consequently, other observationalinstruments were used at
Samarkand, among them parallactical lineals and equinoctial and
solstitial armillary spheres.  These were made of metal and wood
and were on the order of 1 meter in size.  Hand held astrolabes
are not to be included in this list because they were "star
finders" and were used for rough time determination, rather than
for the accurate determination of stellar or planetary positions. 
Typically, two people were required to make individual
observations at any given time.  At Samarkand it was the
practicefor a larger number of people to discuss the results.  In
modern terms, this is like peer review, the purpose of which is
to eliminate sources of error and to ensure the health of the
observational program.  Ulugh Beg himself   has allowed that in
scientific questions there should  be no agreeing until the
matter is thoroughly  understood and that people should not
pretend to  understand in order to be pleasing.  Occasionally,
when  someone assented to His Majesty's view out of  submission
to his authority, His Majesty reprimanded  him by saying 'you are
imputing ignorance to me.'  He  also poses a false question, so
that if anyone accepts  it out of politeness he will reintroduce
the matter and  put the man to shame.[5]    The foreword to Ulugh
Beg's Zij contains four parts: 1) the chronology, describing
various systems of time reckoning; 2) practical astronomy (how
observations are made and used); 3) the apparent motions of the
Sun, Moon, and planets, based on a geocentric system of the
universe; and 4) astrology.   Besides the tables of motions of
the Sun, Moon, and planets,Ulugh Beg's Zij was significant for
its catalogue of about 1000 stars, giving their names and
ecliptic coordinates.  In an appendix to this paper I give a list
of published works that contain all or part of Ulugh Beg's
Zij.[6]  In Flamsteed's Historia Coelestis Britannica (1725) and
Baily's 1843 treatise wecan directly compare Ulugh Beg's
positions with those of Ptolemy,Tycho Brahe, and others. With
modern stellar positions, proper motions, and an accurate
treatment of precession, it would be interesting to make a
statistical analysis of, say, the 100 brightest stars, to see how
these catalogues compare as to average accuracy.[7]   In The
Observatory in Islam Sayili concludes (pp. 391, 393) by stating:  
 The observatory as an organized and specialized  institution was
born in Islam; it went through very  important stages of
evolution within Islam itself; it  passed on in a rather highly
developed state to Europe,  and this was followed, shortly
afterwards, by the  creation of modern observatories of Europe,
in an  unbroken process of evolution superposing upon the 
traditions borrowed from Eastern Islam...The question  is of the case of the Samarqand  Observatory because
it appears as probably the most  important Islamic observatory
from the standpoint of  influences exerted upon Europe.     I can
accept the first half of Sayili's perspective. The astronomical
programs carried out at Baghdad (9th century), Cordova (10th
century), Cairo (10th to 12th centuries), Toledo (11th century),
Castile (under the Christian king Alfonso X; 13thcentury),
Maragha (13th century), and at Samarkand (15th century)were far
more extensive than anything carried out by the ancient Greeks,
with the possible exception of Hipparchus.  The Arabs honored
learning and kept alive the study of astronomy by preserving
Ptolemy's Almagest and adding to its mathematical formulation. 
The Ma'munic, Hakemite, Toledan, Ilkhanic and Alphonsine Tables,
along with the tables contained in Ulugh Beg'sZij have come down
to us because scholars knew they were important.  But the
influence of the Samarkand Observatory on European astronomy was
more indirect than direct.  While copies of Ulugh Beg's Zij
existed in various libraries such as Oxford and Paris not long
after its composition (see Razvi 1985), it only became known in
Europe in the mid-17th century, nearly five decades after the
publication of Tycho Brahe's much more accuratedata (see appendix
to this paper).   If the activities in Samarkand influenced
European ones, whydoes Ulugh Beg only get cursory mention (on pp.
328 and 347, but not in the index) of Dreyer's classic 1890
biography of Tycho Brahe?  In Thoren's even more authoritative
1990 biography of Tycho there is no mention of Ulugh Beg at all.
It was work such as Tycho's, not Ulugh Beg's, that led in turn to
the efforts at Greenwich (founded 1675),  Pulkovo (founded 1839),
and the UnitedStates Naval Observatory (founded 1844), among
other institutions, and these modern, national, facilities did

not needor use Ulugh Beg's work as a fundamental component of the
construction of accurate star catalogues.  Yet, to be fair,
astronomers and historians have found many uses for ancient and
medieval observations, such as studies of the spin down rate of
the Earth, studies of the motion of the Moon and planets, and
thedating of historical events.  Ulugh Beg's observations being
the best of their century allow them to stand as a permanent
observational archive for our benefit.  For example, Shcheglov
(1977) has recently used information from the modern excavation
of Ulugh Beg's large meridian instrument for a study of
continental drift.  The most direct influence of the Samarkand
Observatory was on the construction of the five observatories, or
Jantar Mantars,built by Maharajah Jai Singh (1686-1743) in India. 
Jai Singh wasa Hindu prince in the court of a Muslim Mogul
emperor.  These observatories were built at New Delhi, Ujjain,
Mathura, Varanasi,and Jaipur.  The largest instrument was 27
meters high.  For moreinformation see Kaye (1918), Mayer (1979),
Sharma (1987), and Bedding (1991).  While recognition of Ulugh
Beg's contributions to astronomy was delayed, an extensive body
of information now exists on the activity of his observatory in
Samarkand.[8]  We now know that atthe time Ulugh Beg's
observatory flourished it was carrying out the most advanced
observations and analysis being done anywhere. In the 1420's and
1430's Samarkand was the astronomical capital of the world.  As
such it is deserving of further study.   


[1] Member, International Astronomical Union, Commission 41
(History of Astronomy).    

[2] A zij is an astronomical treatise that usually contains
tables for calculating the positions of the Sun, Moon, and
planets.  It might also contain a star catalogue.    

[3] For a discussion of the astronomical instrumentation of the
Arabs, see Sedillot (1841), Repsold (1908), and Krisciunas
(1988,chapter 2).  Note that the telescope was only first used
for astronomical purposes in 1609.   

[4] Strictly speaking, one must also account for atmospheric
refraction.  For a review of astronomical coordinate systems see
Krisciunas (1988, chapter 1).   

[5] Sayili (1960, pp. 109-110).    

[6] The appendix is largely based on information found in
Shcheglov (1968; 1979) and in the National Union Catalog
Pre-1956Imprints.  I thank Paul Luther for additional

[7] Vogt (1925) found 22' for the average error of 122 Ptolemaic
celestial latitudes.  The best of Tycho's stellar positional
measures are good to 1'.  See Dreyer (1890, pp.387-8), Wesley
(1978), and Thoren (1990, pp. 287-299, and references therein).   

[8] See Kary-Niiazov (1967) and Sirazhdinov (1979).     


Barthold, W. W., Ulugh Beg und seine Zeit. Abhandlungen fur die
Kunde des Morganlandes 21, No. 1, 1935. 

Bedding, James, "Playground for the stars: The Jantar Mantars,
Astronomical Observatories in India," New Scientist, 31 August
1991, p. 49. 

Dreyer, J. L. E., Tycho Brahe: A Picture of Scientific Life and
Work in the Sixteenth Century (Gloucester, Mass.:Peter Smith),
1977 reprint.  (Original edition published by Adam & Charles
Black, Edinburgh, 1890.) 

Kar[y]-N[i]iazov, T. N., "Ulugh Beg", in Dictionary of Scientific
Biography 13, pp. 535-537.    

Kary-Niiazov, T. N., Astronomicheskaia shkola Ulugbeka,
(Tashkent), 1967.    

Kaye, G. R., The Astronomical Observatories of Jai Singh,
(Janpath, New Delhi: Archaeological Survey of India), reprint of
1918 edition.    

Krisciunas, Kevin, Astronomical Centers of the World (Cambridge:
Cambridge Univ. Press), 1988.    

Mayer, Ben, "Touring the Jai Singh Observatories," Sky and
Telescope 58, No. 1, July 1979, pp. 6-10. 

Razvi, Abbas, "The Observatory at Samarqand (Marsad-e-Ulugh Beg,
15th C)," Central Asia, No. 17, 1985, pp. 97-150.    

Repsold, Johann A., Zur Geschichte der Astronomischen
Mess-werkzeuge von Purbach bis Reichenbach (1450 bis 1830)
(Leipzig: Wilhelm Engelmann), 1908.  I have a rough (unpublished)
English translation, which I would be happy to provide anyone, of
the first six sections of this work, covering the astronomical
instrumentation of the ancient Greeks, the Arabs, Purbach,
Regiomontanus, Copernicus, Apian, Wilhelm IV of Hesse-Cassel, and
Tycho Brahe.    

Sarton, George, Introduction to the History of Science
(Baltimore: Williams & Wilkins), 1948, vol. 3, pp. 1120,

Sayili, Aydin, Ulug Bey Ve Semerkanddeki Ilim Faaliyeti Hakkinda
Giyasuddin-i Kasi'nin Mektubu (Ghiyath al Din al Kashi's Letter
on Ulugh Bey and the Scientific Activity in Samarqand) (Ankara:
Turk Tarih Kurumu Basimevi), 1960.  In note 1, pp. 32-33 of this
work it is stated that another English translation was published
by E. S. Kennedy (Orientalia 29, 1960, pp. 191-213), which
differs in many particulars, and that the Persian text of the
letter was published twice before that.    

Sayili, Aydin, The Observatory in Islam and its Place in the
General History of the Observatory (New York: Arno Press), 1981
reprint.  (Original edition published by Turk Tarih Kurumu
Basimevi, Ankara, 1960.)    

Sedillot, L. [P. E. A.], Memoire sur les instruments astron. des
Arabes, Paris, 1841.    

Sharma, V. N., "The Astronomical Efforts of Sawai Jai Singh," in
G. Swarup [et al.], eds., History of Oriental Astronomy
(Cambridge: Cambridge Univ. Press), 1987, pp. 233-240.    

Sh[ch]eglov, V. P., Jan Hevelius: The Star Atlas (Tashkent:
"Fan"Press), 1968. 

Shcheglov, V. P., "Astronomical azimuths of terrestrial objects
as indicators of the rotational motions of the continental
blocks," Soviet Astronomy 21, No. 4, July-August 1977, pp.

Shcheglov, V. P., "Rasprostranenie <> v
evropeiskoi pechati," in Sirazhdinov (1979, see below), pp.

Sirazhdinov, S. KH., ed., Iz istorii nauki epokhi Ulugbeka,
(Tashkent: Academy of Sciences of the Uzbek SSR), 1979. 

Thoren, Victor E., The Lord of Uraniborg: A Biography of Tycho
Brahe (Cambridge: Cambridge University Press), 1990. 

Vogt, H., "Versuch einer Wiederherstellung von Hipparchs
Fixsternverzeichnis," Astronomische Nachrichten, No. 5354-55

Wesley, Walter, "The accuracy of Tycho Brahe's instruments,"
Journal for the History of Astronomy 9 (1978), pp.42-53.      


1648.  John Greaves (1602-1652). Quibus accesserunt, Insigniorum
aliquot Stellarum Longitudines, et Latitudines, Ex Astronomicis
Observationibus Ulug Beigi, Tamerlani Magni Nepotis.  Oxoniae. 
Contains latitudes and longitudes of [98] stars.    

1648.  John Greaves (1602-1652). Binae Tabulae Geographicae, una
Nassir Eddini Persae, altera Vlug Beigi Tatari: Opera et Studio
J. Gravii. Lugduni, Batavorum.  Geographical tables of the Zij.  

1648.  John Bainbridge (1582-1643). Canicularia.  Una cum
demonstratione ortus Sirii heliaci, pro parallelo inferioris
Aegypti.  Auctore Iohanne Gravio.  Quibus accesserunt,
insigniorum aliquot stellarum longitudines, et latitudines, ex
astronomicis observationibus Vlug Beigi. Oxoniae, H. Hall. The
citation in the U. S. Naval Observatory copy states that Greaves
added the catalogue of 98 Ulugh Beg stars to the Bainbridge

1650.  John Greaves (1602-1652). Epochae Celebriores,
Astronomis,Historicis, Chronologis, Chataiorum, Syro-Graecorum
Arabum, Persarum, Chorasmiorum usitatae (Arabice et Latine): Ex
traditione Ulugi Beigi; eas primus publicavit, recensuit, et
Commentarius illustravit Johannes Gravius. Londini, J. Flesher. 
Latin and Persian on opposite pages.  That part of the Zij
dealing with chronology.    

1652.  John Greaves (1602-1652). Binae Tabulae Geographicae, una
Nassir Eddini Persae, altera Vlug Beigi Tatari: Opera et Studio
J. Gravii nunc primum publicatae. Londini, Typis Jacobi Flesher:
prostant apud Cornelium Bee.  2nd edition of geographical tables.

1665.  Thomas Hyde (1636-1703). Tabulae long. ac lat. stellarum
fixarum, ex observatione Ulugh Beighi, Tamerlanis Magni Nepotis,
Regionum ultra citraque Gjihun (i. Oxum) Principis potentissimi.
Ex tribus invicem collatis MSS. Persicis jam primum Luce ac
Latiodonavit, & commentariis illustravit, Thomas Hyde.  In calce
libriaccesserunt Mohammedis Tizini tabulae declinationum &
rectarium ascensionum.  Additur demum Elenchus Nominum Stellarum.
Oxonii: Typis Henrici Hall, sumptibus authoris. Tables in Latin
and Persian for 1018 stars of which about 700 were based
exclusively on Ulugh Beg and the balance were reduced from
Ptolemy in one or both coordinates.  Hyde appears to have worked
totally independent of Greaves.    

1690.  Johannes Hevelius (1611-1687). Prodromus Astronomiae. 
Danzig. Contains a comparison of data in Ulugh Beg's tables with
other star catalogues known at that time -- those of Ptolemy,
Tycho Brahe, Giambattista Riccioli, Wilhelm IV (Landgrave of
Hesse-Cassel), and Hevelius.    

1698-1712. Geographiae veteris scriptores graeci minores. Cum
interpretatione latina, dissertationibus, ac annotationibus... 
Oxoniae, e Theatro Sheldoniano.  A work containing Ulugh Beg's
geographical tables.    

1725.  John Flamsteed (1646-1719). Historia Coelestis
Britannica.London, 3 vols. Includes Ulugh Beg's catalogue, along
with those of Ptolemy, Tycho Brahe, Wilhelm IV, and Hevelius. 

1767.  Gregory Sharpe. Syntagma dissertationum quas olim auctor
doctissimus Thomas Hyde, S. T. P. separatim edidit.  Accesserunt
nonnulla ejusdem opuscula hactenus inedita, &c. &c.  Omnia
diligenter recognita a Gregorio Sharpe, LL.D. Reg. Maj. a
sacris.Templi Magistro S.S.R. et A.S. Oxonii. Reprint, with
corrections,of Hyde's 1665 work on the Zij, in a 2 vol.
collection of Hyde's work. 

1807.  Duo pinakez geographikoi, d men Nassir 'Eddinou Persou, d
de  Ouloug Mpei Tatarou.  'Epimeleia kai opoudh Dhmhtriou
'Alexandridou ... Kata thn en  'Oxonia ekdosin tou sophou
Grauiou.  'En Biennh thz Austriaz, ek thz tupographiaz 'A.
Sxmidiou. Ulugh Beg's geographical tables published in Vienna in
a Greek-language edition. 

1843.  Francis Baily (1774-1844). "The Catalogues of Ptolemy,
Ulugh Beigh, Tycho Brahe, Halley and Hevelius, Deduced From the
Best Authorities, With Various Notes and Corrections," Memoires
of the Royal Astronomical Society 13, pp. 19-28, 79-125, London.
Reprinted from Thomas Hyde's translation, as edited by Gregory
Sharpe in 1767. 

1839.  L. P. E. A. Sedillot (1808-1875). Tables astronomiques
d'Oloug Beg, commentees et publiees avec le texte en regard,
TomeI, 1 fascicule, Paris.   A very rare work, but referenced in
the Bibliographie generale de l'astronomie jusqu'en 1880, by J.
C. Houzeau and A. Lancaster (Brussels, 3 vols. 1887-9; reprinted
London, 1964).    

1847.   L. P. E. A. Sedillot (1808-1875). Prolegomenes des
Tablesastronomiques d'Oloug Beg, publiees avec Notes et
Variantes, et precedes d'une Introduction.  Paris: F. Didot.    

1853.   L. P. E. A. Sedillot (1808-1875). Prolegomenes des
Tablesastronomiques d'Oloug Beg, traduction et commentaire. 

1917.  Edward Ball Knobel (1841-1930). Ulugh Beg's Catalogue of
Stars, Revised from all Persian Manuscripts Existing in Great
Britain, with a Vocabulary of Persian and Arabic Words. 
Washington, D. C.: The Carnegie Institute of Washington.  

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