In the sixteenth century the starry sky played an important role. Not only to find the way by means of the stars, but also because they saw a ‘higher sphere’ in the regular orbits of the celestials, which was determinitive for earthly life to some extent. Astronomers mapped the heaven, astrologers tried to make connections between the stars and earthly developments. Luther did not believe that the earth rotated around the sun, as Nicolaus Copernicus (1473-1543) posed. He did not want to deal with astrology like many of his learned contemporaries. His colleague Melanchthon was more open to it. He took care that both subjects were taught at the University of Wittenberg.