Abū Rayḥān al-Bīrūnī (973 – c. 1050 CE) was a Khwarazmian Iranian scholar and polymath whose skills spanned physics, mathematics, astronomy and natural sciences. He is considered one of the greatest scholars of the medieval Islamic era.
Among his many contributions to astronomy and cartography, Al-Biruni developed the Universal Astrolabe, a significant advancement over earlier models. This device was a major “hardware/firmware upgrade” for its time, capable of performing complex calculations and measurements, including determining the radius of the Earth with remarkable accuracy.