On November 23, 1221, Spanish King and astronomer Alfonso X of Castile was born, who encouraged the preparation of revised planetary tables. These “Alfonsine Tables” a revision and improvement of the Ptolemaic tables, were the best available during the Middle Ages.
Alfonso was born in Toledo, Spain. It is not much known about his early life. However, it is widely believed that he started his career as a soldier when he was only 16 years old, under the command of his father – Ferdinand III of Castile. He succeeded his father as King of Castile and León in 1252. 
During his reign, Alfonso developed an entire court in order to encourage and promote cosmopolitan learning. Numerous of his works were written in Arabic as well as Latin, which he had translated by the court into the vernacular Castilian language. This development encouraged the further advancement of scientific fields like literature, philosophy, and astronomy. 
Back then, the field of astronomy also included astrology and cosmology and Alfonso managed to gain quite a reputation in these fields. Alfonso commanded his scholars to produce new tables in order to update the Tables of Toledo, based on astronomical works and observations by Islamic astronomers, adding observations by astronomers Alfonso had gathered in Toledo. The first printed edition of the Alfonsine tables was probably published in 1483 and another followed in the later 15th century. It is assumed that Nicolaus Copernicus used the the second edition in his work, he is assumed to have bought a copy while at the University of Cracow, and to have it professionally bound with pieces of wood and leather. After the methods of Claudius Ptolemy, the year in the table was divided into 365 days, 5 hours, 49 minutes, and 16 seconds, which was quite close to the currently accepted figure. [2,3]
At yovisto, you may be interested in a video lecture on ‘Rotation in Space‘ by Professor Crawford at Gresham College.
References and Further Reading:
-  In German: Alfons X der Weise
-  In German: Der Sternkatalog des Almagest: die arabische-mittelalterliche Tradition
-  Alfonsine Tables at Britannica
Related Articles in the Blog:
- The Planetary Tables of Erasmus Reinhold
- Nikolaus Copernicus and the Heliocentric Model
- All articles related to Astronomy