One of the most significant observatories of the Middle Ages was built by Ulugbek, the grandson of Amir Temur, in 1424–1428 on the Kuhak hill near Samarkand.
The ruined rounded wall of the observatory along with the lower part of the huge main instrument deepened into the rock by up to 10 meters were found and studied by the archaeologist V. L. Vyatkin in 1908.
Historians say that Ulugbek was a huge fan of astronomy. This observatory made his dreams come true.
The scientific program of the observatory was designed for at least 30 years (the orbital period of Saturn).
Salah al-Din Qadi Zada Rumi, Jamshīd al-Kāshī, Ali Qushji, and other famous astronomers worked at Ulugbek's observatory.
By 1437, the observatory compiledZij-i Sultani, one of the most famous star catalogs.
This star catalog contains the exact coordinates and detailed descriptions of 1,018 visible stars in the sky and 650 cities.
The exact duration of an astronomical year — 365 days, 6 hours, 10 minutes and 8 seconds — was also determined there.
Today, the most accurate value of this parameter is 365 days 6 hours 9 minutes and 9.6 seconds.
Therefore the actual error was less than 1 minute.
After the death of Ulugbek, the observatory continued to work for another 20 years.
The abandoned building of the observatory existed for a long time and was fully dismantled only at the beginning of the 16th century.
The ruined rounded wall of the observatory along with the lower part of the huge main instrument deepened into the rock by up to 10 meters were found and studied by the archaeologist V. L. Vyatkin in 1908.
Historians say that Ulugbek was a huge fan of astronomy. This observatory made his dreams come true.
The scientific program of the observatory was designed for at least 30 years (the orbital period of Saturn).
Salah al-Din Qadi Zada Rumi, Jamshīd al-Kāshī, Ali Qushji, and other famous astronomers worked at Ulugbek's observatory.
By 1437, the observatory compiledZij-i Sultani, one of the most famous star catalogs.
This star catalog contains the exact coordinates and detailed descriptions of 1,018 visible stars in the sky and 650 cities.
The exact duration of an astronomical year — 365 days, 6 hours, 10 minutes and 8 seconds — was also determined there.
Today, the most accurate value of this parameter is 365 days 6 hours 9 minutes and 9.6 seconds.
Therefore the actual error was less than 1 minute.
After the death of Ulugbek, the observatory continued to work for another 20 years.
The abandoned building of the observatory existed for a long time and was fully dismantled only at the beginning of the 16th century.