Alfonsine tables
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The Alfonsine tables (sometimes spelled Alphonsine tables) were ephemerides (astronomical tables that show the position of the sun, moon and planets relative to the fixed stars) drawn up at Toledo by order of Alfonso X around 1252 to 1270.
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[edit] Production
Alfonso X assembled a team of scholars including both Jews and Moors to produce a new ephemeris that corrected anomalies in the Tables of Toledo. They were able to exploit arabic astronomical discoveries as well as earlier astronomical works preserved by Islamic scholars. New observations were used to augment these sources.[1]
The Alfonsine tables were originally written in the Castilian form of Spanish[2] but became better known when they were later translated into Latin. Georg Purbach used the Alfonsine tables for his astronomy book, Theoricae novae planetarum (New Theory of the Planets). The first printed edition appeared in 1483. The primary use of these and similar tables was to help in the construction of horoscopes by astrologers.
[edit] Methodology
The methods of Claudius Ptolemy were used to compute the table and they divided the year into 365 days, 5 hours, 49 minutes, 16 seconds - very close to the currently accepted figure. There is a famous (but apocryphal) quote attributed to Alfonso upon hearing an explanation of the extremely complicated mathematics required to demonstrate Ptolemy's geocentric model of the solar system - "If the Lord Almighty had consulted me before embarking on creation thus, I should have recommended something simpler." (The validity of this quotation is questioned by some historians.[3]) This quotation has been used to illustrate the large number of additional epicycles introduced into the Ptolemaic system in an attempt to make it conform with observation. However, modern computations[4] have concluded that the methodology used to derive the Alfonsine tables was Ptolemy's unmodified theory and that the original computations were correct.
[edit] Popularity
The Alfonsine tables were the most popular astronomical tables in Europe and updated versions were regularly produced for three hundred years. Copernicus himself owned a copy. In 1551, the Prutenic Tables (or Prussian Tables) of Erasmus Reinhold's were published . These tables used the Copernican heliocentric model of the solar system. Copernicus's publication - De revolutionibus - was not easy to use and the Prutenic tables were intended to make the heliocentric model more usable by astologers and astromomers. However, the Prutenic tables were not widely adopted outside German speaking countries and new versions of the Alfonsine tables continued to be published[5] until the publication of the Rudolphine Tables in 1627.
[edit] References
- ^ Noah J. Efron, Judaism and science: a historical introduction(Greenwood Publishing Group, 2007)
- ^ Thomas F. Glick, Steven John Livesey, Faith Wallis, Medieval science, technology, and medicine: an encyclopedia (Routledge, 2005)
- ^ Owen Gingerich, "Alfonso X as Patron of Astronomy."
- ^ Owen Gingerich: The Book Nobody Read. Walker, 2004, Ch. 4 (ISBN 0-8027-1415-3)
- ^ http://www.hps.cam.ac.uk/starry/tables.html
