The Appearance of the Medicean Moons in 17thCentury Charts and Books—How Long Did It Take?

Abstract

AbstractGalileo's talents in perspective andchiaroscurodrawing led to his images of the Moon being accepted relatively quickly as the naturalistic portrayal of a truly physical place. In contrast to his resolved views of the Moon, Galileo saw the satellites of Jupiter as only points of light (as with stars). He thus used star symbols inSidereus Nuncius(1610) for the moons, in constrast to an open disk for Jupiter. In this paper, I describe methods used in subsequent decades to portray objects that could not be seen in any detail but whose very existence challenged the scholastic approach to science. Within fifty years, the existence of the moons was such an accepted component of astronomy that they were depicted in the highly decorative “textbook”Atlas Coelestis seu Harmonia Macrocosmicaby Andreas Cellarius (1660). Other symbolic methods, ranging from the routine to the dramatic, were used in subsequent centuries to portray the moons. Actual photographs using ground-based telescopes were not possible until the 20thcentury, just years before cameras on spaceflight missions captured the true details of the Medicean Stars.