Copernicus's Chord Tables

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This Demonstration reconstructs Copernicus's chord (sine) table from De lateribus et angulis triangulorum [1], published by Rheticus. Rheticus (1514–1574) was a student of Copernicus (1473–1543). The book contains a table of chords (sines) for every minute of the quadrant and for a radius of , that is, using formula . So the chords were given to seven places. The differences were also calculated.

Contributed by: Izidor Hafner (January 2016)
Open content licensed under CC BY-NC-SA



The table's contents were taken from Regiomontanus's works [2, p. 3]. The picture is taken from [1].


[1] N. Copernicus (G. J. de Porris [Rhaeticus], ed.), De lateribus et angulis triangulorum,Vittembergae: excusum per Johannem Lufft,1542.

[2] D. Roegel, "A Reconstruction of the Tables of Rheticus' Opus Palatinum (1596)," Dec 6, 2010.

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