The Imperial Astronomer

Samuel Thrope

Prince Muhammad Taraghay ibn Shahrukh (1394–1449), better known by his title Ulugh Beg, was bored by politics. Raised in the court of his grandfather Tamerlane, the famous conqueror who established the Timurid Empire in today’s Afghanistan, Iran, and Central Asia, Ulugh Beg was born to rule. But after being appointed governor and then reigning ineffectually as the Timurid sultan for a scant two years, Ulugh Beg was murdered by his own son in 1449.

What excited Ulugh Beg was mathematics. In 1417, when he was only twenty-three, the young prince founded a madrasa (religious college) in the city of Samarkand, already a cultural and intellectual center. At this madrasa, in contrast to others, mathematics and astronomy were emphasized as much as the study of the Qur’an, the law, and the traditions of the Prophet. The madrasa and Ulugh Beg’s patronage attracted scientists from far and wide, notably Qadi Zada al-Rumi from Bursa in today’s Turkey and Jamshid al-Kashi from Kashan, Iran. Ulugh Beg not only took an active part in these scholars’ seminars but, in 1420 he also founded and directed an innovative astronomical observatory, the remains of which can still be seen today.

The fruit of these scholars’ observations can be found in the manuscript pictured here. Known as the Zij-i Jadid-i Sultani, or Zij-i Ulegh Beg, it contains a comprehensive set of astronomical tables designed to help astronomers measure time and compute the positions of the stars and planets and to assist in the conversion of dates between the multiple calendars — Islamic, Persian, Seleucid, and others — in use at the time. While many other similar astronomical tables were written, Ulugh Beg’s is the most accurate and extensive and continued to be consulted until the nineteenth century.