Astronomical Tables and Canons in the Alfonsine Tradition (Symposium ICHST 2021)

The year 2021 marks the eight hundredth anniversary of the birth of King Alfonso X, a man whose name now serves as a moniker for an astronomical tradition that came to dominate Latin Europe from ca. 1320 – 1600. During that time, the heavens were an important element of social, cultural, and political life, and Alfonsine astronomy stood at the core of understanding and determining celestial motions. This symposium brings together four papers each of which explores a figure who was an exponent of Alfonsine astronomy, and whose work represented the further elaboration of this multi-domain tradition. Alfonsine astronomy took many forms, including tables, procedural canons, theoretical treatises, diagrams, ephemerides, and instruments. In this instance, the papers of this symposium have singled out research in two of these domains, with two papers focusing on astronomical tables and two on  canons. Tables and canons provide the most important instance for astronomy’s former impact on cultural  life: every prognostication and divination was based on the position of the celestial bodies as they follow from the tables and corresponding canons of Alfonsine astronomy. Understanding those two, therefore, along with their practitioners and practices, also contributes to the history and historiography of the astral sciences and its socio-political influence.


  • Nick Jacobson, Conrad Heingartner’s Notes on Canons for Finding Planetary Latitudes
  • Laure Miolo, Building new astronomical tools: a mise en perspective of the equation of time in Lewis of Caerleon’s astronomical works
  • Stefan Zieme, The hierarchical structure of tables: Lewis of Caerleon on the equation of time
  • Camille Bui, Planetary latitudes tables in Conrad Heingarter’s astronomical manuscripts