Abu Mahmud Hamid ibn Al-Khidr Al-Khujandi was a Astronome Perse of the 10th century born with the neighborhood of 940 and died in 1000. It helped to build a observatory with Ray, close to Teheran, in Iran.

The only facts known in connection with its life come from its writings and the comments made by Nasir AD-DIN At-Tusi. According to him, Al-Khujandi was one of the governors of a Mongolian tribe in the area of Khodjent (today with the Tadjikistan), it thus belonged probably to the nobility.

Khujandi worked under the direction of the emir buwayhide of Ray, where it is known to have built gigantic a Sextant in 994.