In the city of Aleppo, during the tenth century of the Common Era, a woman named Mariam al-Ijliya, more widely known by her professional title al-Astrulabi, became one of the most accomplished instrument makers of the Islamic Golden Age. She did not arrive at this craft by accident. Her father, known as al-Ijliyy al-Asturlabi, had trained as an apprentice under an astrolabe maker in Baghdad, then one of the great intellectual capitals of the world. Mariam grew up inside that craft, absorbing both the technical precision and the mathematical rigour that astrolabe-making demanded.
An astrolabe is a remarkable instrument by any historical standard. Built from a disc of metal or wood, marked with precise degree measurements around its circumference, and fitted with a rotating pointer known as an alidade, it allowed its user to calculate the position of the sun, moon, stars, and planets. With it, an astronomer could determine the time of day or night, the season, the latitude of their location, and the altitude of any celestial body above the horizon. It was, in essence, a portable, mechanical model of the visible heavens.
To understand why Mariam’s work mattered so deeply to her society, it helps to understand what the astrolabe was actually used for in the daily life of a Muslim community. Islamic practice requires precision around time and direction in a way that few other traditions do. Five daily prayers, each tied to the specific position of the sun. A direction of prayer, the Qibla, that must be calculated accurately toward the Kaaba in Makkah regardless of where in the world the worshipper stands. The beginning of Ramadan and the arrival of Eid, both determined by the observation of celestial bodies.
This is the deeper story behind the astrolabe’s importance in the Islamic world. It was never simply a scientific curiosity pursued for its own sake. The instrument existed because the Muslim community needed a reliable way to fulfil its obligations of worship with accuracy, wherever its people happened to live. Mathematics, metallurgy, and astronomy were not separated from faith in the intellectual culture Mariam inherited. They were in service of it. Her precision as a craftswoman was, in a very real sense, an act of supporting her community’s worship.
Mathematics, metallurgy, and astronomy were not separated from faith. They were in service of it.
Mariam’s skill did not go unnoticed. Sayf al-Dawla, the founder of the Hamdanid Emirate of Aleppo, who ruled over much of northern Syria and parts of the western Jazira region from 944 to 967 CE, took note of the intricacy and innovation in her designs. He invited her to join his court, a position that placed her among the scholars, poets, and scientists that Sayf al-Dawla was known for patronising. From this position, Mariam’s astrolabes contributed directly to advances in navigation and timekeeping that extended well beyond the borders of Aleppo itself.
What makes her accomplishment particularly striking is the level of mathematical sophistication her work required. Producing an astrolabe capable of accurately tracking celestial positions demanded an understanding of geometry, trigonometry, and applied astronomy, combined with the metalworking skill to translate those calculations into a functioning physical object. Some academic studies of her work have noted that she appears to have achieved this level of precision without having received formal classroom instruction in mathematics, a testament to the depth of practical and inherited knowledge that skilled craft traditions of the period could produce.
Mariam’s contribution to astronomy was eventually given a permanent place in the very field she helped advance. In 1990, astronomer Henry E. Holt, observing from the Palomar Observatory, discovered a main-belt asteroid and named it 7060 Al-Ijliyye in her honour. More than a thousand years after she shaped metal and mathematics into instruments that read the sky, her name now orbits within it.
Her story has also reached audiences far beyond the history of science. In 2016, author Nnedi Okorafor published Binti, a science fiction novella whose protagonist, an astrolabe-making prodigy, draws direct inspiration from Mariam’s life and craft. Okorafor has spoken about first encountering Mariam’s story at a book festival in the United Arab Emirates, and the character she built in tribute went on to win the Nebula Award, introducing a new generation of readers to a name that had largely remained confined to specialist historical scholarship.
It is worth noting that the astrolabe itself was not an Islamic invention. The instrument originated with the ancient Greeks, who used it primarily to measure latitude. What the scholars of the Islamic Golden Age, Mariam among them, contributed was refinement, expansion, and a far broader application that connected the instrument directly to the spiritual and practical needs of a global Muslim community. This pattern, taking an inherited tool and developing it with such depth that it becomes inseparable from a new tradition, runs throughout the story of Islamic scientific achievement.
Mariam al-Astrulabi’s career sits alongside the better-known names of the Islamic Golden Age: Ibn Sina, al-Biruni, Ulugh Beg, Ali al-Qushji. Her work belongs in that same lineage of scholars who refined the scientific inheritance of Greece, Persia, and India into instruments and ideas that would later inform the European Renaissance. That she did so as a woman, working in a craft passed down through her father and recognised at the highest levels of her society’s court, makes her story a part of Islamic history that deserves to be told as often and as fully as those of her male contemporaries.