Ulugbek’s Observatory

This unique construction was built in 1428- 1429 by a ruler of Maverannakhr and an outstanding scholar of his time – Mirzo Ulugbek. It was a three-floored building of cylindrical form, 46 meters in diameter and 30,4 meters high. External walls were decorated with delicately made tiles. The foundation of the observatory is an azimuth quadrant which had a 40,212 meters radius and 63 meters length. The main tool was a sextant, oriented to meridian line from south to north.

There were other instruments in the observatory besides the main one. Ulugbek and his colleagues made different astronomical observations such as: ranging Sun, Moon and planets passing meridian; determination of obliquity of the ecliptic to equator and the length of the sidereal year; calculation the valuation of sine of one angle degree- an important astronomical constant- with the digit precision of 18th character after the decimal point!

The crown of the scholar work became a tractate “Zidji-Guragan” (Catalog of stars) which contains results of his astronomical researches. The catalog contains coordinates of 1018 stars, determined by Samarkand observatory with the incredible accuracy for the first time after Gipparkh.

Being an outstanding scientist, Ulugbek wasn’t a good military leader. He used to spend much of his time in the observatory and paid less attention to the government affairs. His eldest son, Abd al-Latif, who was under the influence of a radical religious group ordered to kill his father. The son offered his farther a pilgrimage to Mecca. On the way to Mecca Ulugbek was deceitfully beheaded with Abd-al-Latif’s connivance.

After the tragic death of Ulugbek, radical part of the religious community provoked destruction of the observatory. The scholars, who worked in this famous scientific center, were disbanded and the most valuable library was plundered. The building of the observatory was destroyed and in the end of the XVII century nothing was left from the observatory.

Though Ulugbek died, his bright star didn’t die out. Ali Kushji, a true follower of Ulugbek, had to escape from Samarkand to Europe with the catalogue of stars. Later, Ulugbek’s name and his scientific achievement became famous among the European and Asian scientists. “The Catalogue of stellar sky”, published in the XVII century in Europe by Jan Geveliy has an engraving on which a symbolic meeting of the greatest astronomers lived in different countries at different times is depicted. Ulugbek is also represented among them. Author of this engraving imaged Ulugbek without having his picture.

The location of Ulugbek’s observatory was unknown to historians for a long time and only in 1908, Samarkand archaeologist V.L. Vyatkin could find the ruins of the observatory in the result of his thorough studies of the old documents.

Interesting things connected with the life of the Great Ulugbek are exhibited in museum on the territory of observatory.