This is an ancient astronomical device. It was used to measure horizontal angles and determine the latitude and longitude of celestial bodies. The famous Siberian researcher Igor Belich revealed its history. In his opinion, the astrolabe in the exhibition of the Governor’s Palace of the Tobolsk Museum comes from the city of Isfahan, which in Iran was often called Nesfe Jahan — “Half of the world”. It was probably made in the 17th century, when Isfahan was the capital of the Safavid state. And the European (they are also Arabic) numbers on its outer ring of the scale, digitized in degrees and hours, were engraved later, when it came to the Russian Empire.

By this relic we can tell about intellectual life of the Siberian Muslims of the 19th century. It points to broad cultural ties and, of course, a notable level of interest in traditional Muslim Sciences.

The “Science of the stars” (or an-nudzhum), or astronomy, improved in the Arab world and has always been an honorable and encouraged occupation all over the Muslim East. Natural science knowledge helped Muslims to conduct five daily prayers - namaz and observe the fast in the month of Ramadan.

Drawing up the lunar calendar determined the beginning and end of the month of fasting, and the correct determination of the direction of prayer – Qibla – was considered one of the conditions for its viability. It is not surprising that Siberian Muslims have long sought to obtain perfect astronomical knowledge and, following the testament of Ishmael, went to study in distant countries, primarily in such centers of Islamic theology in Central Asia as Bukhara, Samarkand, Tashkent and others.

From the Russian translation of the book of Abd Al-Rashid Ibrahimov “Siberian scientists of the past and present” it is known that this astronomical device belonged to the famous imam Davlet-Baki b Ali Asfaru, who twice went to Bukhara-Yi Sharif to study these sciences. But after the second trip, he died on his way back. After his death, astronomical devices and related scientific books were sent to his family. And since there were no direct heirs in the family, the books fell into the hands of Niyaz Aytikin. One of the sons of Niyaz-Haji, Nasr ad-Din, handed over the astrolabe of the said Mullah to the Tobolsk Museum.