Ulugbek’s Observatory was constructed on Kukhak hill due to Mirzo Ulugbek’s order in 1428-1429.
The most important achievement of astronomers from Samarkand is starts catalogue made by them so-called “Zidj of Ulugbek” or “Zidj Gurgony”. The value of that catalogue is that there are the coordinates of 1 018 stars. Astronomers of Samarkand spent long time working on these tables and finished them in 1437, but changes and additions had been included by Ulugbek himself till his death.
After Ulugbek’s death, observatory has worked for 20 years more. Only in 1469, after the killing of Samarkand’s governor – Abu Sayd by his son Mirza Sultan Akhmad, the condition of the scientists was so bad that Ali Kushchi with his pupils had to leave the observatory and move to Herat where the first state minister was a great Uzbek port – Alisher Navoi. Soon, the astronomer was invited to Istanbul. There he had finished and published the works of the observatory. Astronomic tables made at the observatory, had been very popular in the East and during long period were considered matchless due to their exactness. In Europe they were firstly published in 1650.
The building of the observatory was empty for several years more and only by the beginning of 16th century it was dismantled into bricks. At the beginning of 20th century, the location of the Ulugbek’s observatory was found by archeologists of Samarkand V.L. Vyatkin.
The main thing in the observatory is a huge goniometer instrument – sextant or quadrant – a vertical circle. It was exactly oriented by meridian from south to north and used for the observation over the Sun, Moon and other planet of the firmament. The part of this instrument that has been preserved till our days was lowered to deep narrow trench inside of the rocky foundation of the hill where two parallel arch-lines of burnt bricks are united with each other by alabaster.
Ulugbek’s observatory is decorated with a wonderful engraving by Holland painter of 17th century with an inscription over Ulugbek’s portrayal.
In 1964 near the place where the observatory had been situated, the memorial museum of Ulugbek was opened. Fragments of famous stars tables made by Ulugbek and his comrades, photos of excavations, collection of ancient astronomic instruments, frescos depicting episodes of astronomer’s life are represented here in the museum.