Copernicus Circulates Heliocentric Commentariolus

By 1514, Nicolaus Copernicus circulated his manuscript 'Commentariolus' to colleagues in Frombork. The six-page treatise presented a sun-centered cosmic system with seven assumptions, proposing that Earth orbits the Sun annually while rotating daily on its axis. This challenged the 1,400-year-old Ptolemaic geocentric model that dominated Renaissance Europe. The work lacked the mathematical detail of his later publications but provided the foundation for his comprehensive 'De Revolutionibus Orbium Coelestium,' which he published nearly three decades later in 1543.