Polar-axis sundial of the Umayyad Mosque
Reloj de sol con gnomon polar de la mezquita de los Omeyas
- Date
- 1371 · confidence high
- Place
- Umayyad Mosque, Damascus, Syria
- Credited to
- Ibn al-Shatir
- People
- 👤 Ibn al-Shatir1304–1375
- Field
- Knowledge & symbols
⚠️ Disputed: the sources disagree.
What it is
Large marble sundial with its gnomon set parallel to the Earth's axis, marking equal hours throughout the year. It is the oldest surviving polar-axis sundial.
The original was replaced by a copy in 1876 (fragments are today in the National Museum of Damascus). The polar-gnomon idea may have had earlier precedents that do not survive.
What it led to
- equal hours on sundials
- modern polar-axis sundials
- timekeeping for prayers (ilm al-miqat)