In 1540, he designs, prints and publishes at Ingolstadt one of the finest books of his time, the Astronomicum Caesareum, for explaining the position and movements of stars and planets to the Emperor Charles V. His effort was rewarded: a comfortable pension is promised and he is knighted.
The book is produced by woodcut and brightly colored. In the fashion of his time, sun and moon have faces. The plates include charts that allow the calculations. It is a very interesting example of an old book with mechanisms : some elements are rotating on the principle of the volvelles, and beads moving along colored cords facilitate the marking.
The book includes 36 full-page illustrations. The map of the constellations is illustrated with human and animal figures, similar as those used by Dürer for the Emperor Maximilian on the concept of Stabius a quarter of a century earlier.
His use of the geocentric system three years before Copernicus' book unfortunately discredited this great work of both science and education.
A copy of the Astronomicum Caesareum is estimated £ 600K, for sale by Koller in Zurich on September 20, lot 402 shared on Invaluable. It still has volvelles and cords but not the beads, and its binding is later.
The exceptional quality of design of the book is illustrated by the page of the months shared by Wikimedia, probably from another copy: