Sidereus nuncius

7.  Telescope

When Galileo first turned the newly invented telescope to the heavens, this became the first printed account of his new discoveries, including mountains and valleys on the face of the moon, four satellites of Jupiter, the countless stars of the Milky Way, and earthshine.

Often translated as "Starry Messenger", "Starry Message" or "Sidereus Messenger", the complete title is "Sidereus nuncius : magna, longeque admirabilia spectacula pandens, suspiciendaque proponens vnicuique, praesertim verò philosophis, atq[ue] astronomis, quae à Galileo Galileo ... perspicilli nuper à se reperti beneficio sunt obseruata in lunae facie, fixis innumeris, lacteo circulo, stellis nebulosis, apprime verò in quatuor planetis circa Iouis stellam disparibus interuallis, atque periodis, celeritate mirabili circumuolutis; quos, nemini in hanc vsque diem cognitos, nouissimè author depraehendit primus; atque Medicea sidera nuncupandos decreuit."

The book contains five copper-engravings showing the lunar surface and phases; three woodcut star maps; and two unnumbered leaves with a diagram of the Pleiades constellation inserted between leaf 16 and leaf 17. Our copy is imperfect: the diagram of the Pleiades has been closely trimmed, cutting off at least one of the stars.