Ptolemy, Bianchini, and Copernicus: tables for planetary latitudes (Q1880866)

The paper starts with a brief survey of the history of tables for planetary latitudes in Ptolemaic astronomy, focussing on the latitudes of Venus and Mercury. According to the author, Ptolemy gives a full treatment of planetary latitudes for the inferior planets, for which he refers to three components which are called \textit{declinatio, reflexio} and \textit{deviatio} in the Latin tradition. Ptolemy's tables, however, display only the first two of theses components, whereas Giovanni Bianchini (second half of the 15th century) was one of the very few astronomers who called attention to the third component of latitude for Venus and Mercury, and who produced tables for it. The central topic of the paper is a detailed description of Bianchini's tables. In the last part of the article, the author argues that Copernicus strongly depended on Bianchini's tables which can therefore be considered as an important source for Copernicus's knowledge of astronomy.