A facsimile of a copy of Galileo's Sidereus nuncius in the Library of Congress, Rare Book and Special Collections.

"Sidereus Nuncius (usually Sidereal Messenger, also Starry Messenger or Sidereal Message) is a short astronomical treatise (or pamphlet) published in New Latin

Galileo’s telescopic discoveries, and especially his observation of sunspots, caused great debate in an age when the heavens were thought to be perfect and un

Directing his polemics against the pedantry of his time, Galileo, as his own popularizer, addressed his writings to contemporary laymen. His support of Copernic