#OTD 1616. Galileo Galilei is formally banned by the Roman Catholic Church from teaching or defending the view that the earth orbits the sun.
In 1610, he published his Sidereus Nuncius, describing the observations that he had made with his new, much stronger telescope, amongst them, the Galilean moons of Jupiter. With these observations and additional observations that followed, he promoted the heliocentric theory of Copernicus published in De revolutionibus orbium coelestium.