Observatory of Ulugbek in Samarkand
Ulugbek Observatory
The Ulugbek Observatory is one of the most significant astronomical monuments of the Middle Ages, situated on Kuhak Hill in the vicinity of Samarkand, Uzbekistan. Built between 1424 and 1428 by the renowned astronomer and ruler Ulugbek, the observatory stands as a symbol of scientific achievement and intellectual advancement during the Timurid era. Today, it remains one of the key attractions in Samarkand for those interested in history, science, and the legacy of the Silk Road.
Historical Discovery and Excavation
The remains of the Ulugbek Observatory were discovered in 1908 by archaeologist V.L. Vyatkin, who identified the site using a 17th-century document describing land donations to a nearby Dervish monastery. Subsequent excavations, notably the 1948 expedition led by archaeologist V.A. Shishkin from the Uzbek SSR Academy of Sciences, revealed the observatory’s foundations and significant architectural fragments buried in natural rock.
Architectural Design and Astronomical Instruments
Reconstruction studies suggest that the observatory was a three-story cylindrical building standing 30.4 meters high and measuring 46.4 meters in diameter. Its most remarkable feature was a grandiose goniometer oriented north-south—a massive sextant or quadrant with a radius of 40.21 meters. This instrument was used to measure the altitude of celestial bodies as they crossed the meridian, enabling precise astronomical observations.
The excavated instrument is still well-preserved underground. It consists of an arc representing one-sixth of a circle, calibrated from 20° to 80°, bordered by marble barriers with degree markings engraved into the stone. Each degree on the arc spans 70 cm, and brick staircases run alongside the barriers, allowing astronomers to access the measurement scales for their observations.
Scientific Contributions and Achievements
Besides vertical measurements, azimuth observations were carried out on the observatory’s roof, which once hosted additional astronomical instruments, though these have not survived. Notable scientists such as Kazi-zade ar-Rumi, al-Kashi, and al-Kushchi worked alongside Ulugbek at the observatory. Their collective efforts led to the compilation of the Gurgan Zij by 1437—a comprehensive star catalog that documented 1,018 stars and included remarkably accurate calculations of the solar year’s length as 365 days, 6 hours, 10 minutes, and 8 seconds, with only a 58-second margin of error.
Ulugbek Observatory Museum
To honor Ulugbek’s astronomical legacy, the Ulugbek Observatory Museum was established in 1970. The museum houses reproductions of Arabic manuscripts, including Ulugbek’s famous star charts and the Zij-i Sultani, as well as significant European printed editions of his work. Visitors can also explore historical astronomical instruments such as astrolabes and a miniature model of the observatory, offering insights into medieval scientific endeavors in Samarkand.
Today, the Ulugbek Observatory stands as a testament to the scientific brilliance of Central Asia and remains an essential destination for those exploring the historical treasures of Samarkand and the Silk Road.
Entrance fee: 2.5 USD