De revolutionibus orbium coelestium De revolutionibus orbium coelestium De revolutionibus orbium coelestium ("On the Revolutions of the Heavenly Spheres") is the seminal work on the heliocentric theory of the Renaissance astronomer Nicolaus Copernicus (1473–1543). The book, first printed in 1543 in Nuremberg, Holy Roman Empire, offered an alternative model of the universe to Ptolemy's geocentric system, which had been widely accepted since ancient times. Copernicus initially outlined his system in a short, untitled, anonymous manuscript that he distributed to several friends, referred to as the "Commentariolus". A physician's library list dating to 1514 includes a manuscript whose description matches the "Commentariolus", so Copernicus must
The Mask of the Sun entitled "The Serpent's Star" was developed in 1983 by Ultrasoft and published by Brøderbund. The Mask of the Sun The Mask of the Sun is an graphical interactive fiction game developed by Ultrasoft and published in North America by Brøderbund and in Europe by Ariolasoft. It was released in 1982 for the Apple II, Atari 8-bit family, and Commodore 64. The hero is Mac Steele, an archaeologist who needs to find the Mask of the Sun in order to obtain an antidote to a poison that afflicts him from an artifact that he found. The game mostly takes place in