Ulugh Beg (March 22, 1394 - October 27, 1449), born Muhammad Taragai ibn
Shakhrukh ibn Timur Gurgan, Mongol-Turkish astronomer and mathematician
from what is today Uzbekistan.
Ulugh Beg, meaning "Great Prince" was the
grandson of the Mongol warlord Timur (aka Tamerlane) and the son of Shakhrukh,
and was appointed the viceroy of the province of Transoxiana (then
Maverannakhr) by his father, between 1405 and 1410. The capital of the
province was established in Samarkand. Ulugh Beg showed an aptitude for
scientific pursuits from an early age. His father and grandfather attracted
scholars to Samarkand, and Ulugh Beg took full advantage of this.
When he came to power in
Samarkand, he was a willing patron of the madrasa (Russian: medresa) -
essentially a university - and funded construction of its observatory.
Under his patronage, the observatory completed the Zij-i-Gurgani or
Zij-i-Ulugh Beg - a summary
of astronomical and mathematical knowledge up to the fifteenth century, similar
to but more advanced than Ptolemy's Almagest. It
included a catalogue of
1018 stars visible to the naked eye, with positions accurate to within five
arcseconds (measured with Samarkand's giant 40-meter quadrant), an amazing
achievement for the time. The Zij-i-Gurgani also gave the Earth's precession
rate as 51.4 arcseconds per year, very close to the 50.2 arcseconds per year
now known to be correct for that era. The Zij is considered one of the three
greatest works of Muslim astronomy. The observations were completed in 1437,
and the results published (in Persian, Arabic, and Tadjik) a few years
later. His book was unknown in Europe until it was translated in part by
John Greaves of Oxford University in 1648, and finally published in full
by Thomas Hyde (also of Oxford) in 1665.
Ulugh Beg was not directly involved in taking observations, but left that to
the observatory staff under the directorships of
Jamshid Al-Kashi and Qadi Zada, and
the observer Ali ibn Muhammad al-Qushchi. However, he was deeply involved
in the editing and review of the final work. Interestingly, he was very
strongly devoted to the search for truth and accuracy, to the point of using
his position of power to advance a false idea, then chastizing people who
agreed with him out of deference to his rank and power.
His father, Shakhrukh, died in 1447 and passed control of his kingdom to
Ulugh Beg, which drew him away from his scientific pursuits. Ulugh Beg was
assassinated in 1449 under the orders of his son, Abdul Latif, who was
himself murdered a year later. Ulugh Beg's death and the end of his patronage
of the observatory put an end to the astronomical work at Samarkand.
Archaeological excavation of Ulugh Beg's observatory was carried
out by V.L. Vyatkin in 1908 and 1914, and Ulugh Beg's tomb (in the
mausoleum of Tamerlane) was uncovered in 1941 and 1948 by the expeditions
of T.N. Kari-Nazov. Ulugh Beg had been buried with the honors of a martyr.
Sources: Kevin Krisciunas' excellent Astronomical
Centers of the World, Cambridge University Press, 1988, and Astronomi:
Biograficheski Spravochnik by I.G. Kolchinski, A.A. Corson, and M.G.
Rodriguez, Naukova Dumka, Kiev, 1986.