The recovery of the great scientific treatise of Alonso de Santa Cruz: Astronómico Real

Abstract

The precious manuscript entitled Astronómico Real, written by the cosmographer Alonso de Santa Cruz as a commission from Emperor Carlos and dedicated to Felipe II, had been considered lost. As part of their line of research, the authors of this article located and analyzed the text. The name of the Sevillian cosmographer had been erased and replaced by the name Andrés García de Céspedes, a later cosmographer. A detailed study, using biographical data already known and new information taken from unpublished letters written by the cosmographer to the Emperor and his son, reveal without any doubt that Santa Cruz is the real author of this transcendental work. The manuscript of 256 double-sided pages and illustrated with magnificent drawings, some with moveable wheels in different colours, is divided into three parts: first, a Teatrise on the sphere; second, a translation with commentaries of Purbachio's theories of the planets; third, and annotated and elarged version of the Apiano's Astronomicum Caesarewm, supplemented by a Chronology or Repertoire. The test shows the excellent astronomical (and astrological) knowledge of its author, who was also chronicler, cartographer and geographer.