Quotes from book
Sidereus Nuncius

Galileo Galilei Original title Sidereus nuncius magna longeque admirabiblia spectacula pandens, suspiciendaque proponens vnicuique praesertim vero philosophis (Latin, 1610)

Sidereus Nuncius is a short astronomical treatise published in New Latin by Galileo Galilei on March 13, 1610. It was the first published scientific work based on observations made through a telescope, and it contains the results of Galileo's early observations of the imperfect and mountainous Moon, the hundreds of stars that were unable to be seen in either the Milky Way or certain constellations with the naked eye, and the Medicean Stars that appeared to be circling Jupiter.The Latin word nuncius was typically used during this time period to denote messenger; however, it was also rendered as message. Though the title Sidereus Nuncius is usually translated into English as Sidereal Messenger, many of Galileo's early drafts of the book and later related writings indicate that the intended purpose of the book was "simply to report the news about recent developments in astronomy, not to pass himself off solemnly as an ambassador from heaven." Therefore, the correct English translation of the title is Sidereal Message .


Galileo Galilei photo
Galileo Galilei photo
Galileo Galilei photo

“About ten months ago a report reached my ears that a certain Fleming had constructed a spyglass by means of which visible objects, though very distant from the eye of the observer, were distinctly seen as if nearby. Of the truly remarkable effect several experiences were related, to which some persons gave credence while others denied them. A few days later a report was confirmed to me in a letter from a noble Frenchman in Paris, Jacques Badovere, which caused me to apply myself wholeheartedly to inquire into means by which I might arrive at the invention of a similar instrument. This I did shortly afterwards, my basis being the theory of refraction. First I prepared a tube of lead, at the ends I fitted two glass lenses, both plane on one side while on the other side one was spherically convex and the other concave. Then placing my eye near the concave lens I perceived objects satisfactorily large and near, for they appeared three times closer and nine times larger than when seen with the naked eye alone. Next I constructed another one, more accurate, which represented objects as enlarged more than sixty times. Finally, sparing neither labor nor expense, I succeeded in constructing for myself so excellent an instrument that objects seen by means of it appeared nearly one thousand times larger and over thirty times closer than when regarded with our natural vision.”

Translation by Stillman Drake in Discoveries and Opinions of Galileo (1957)
Sidereus Nuncius (Venice, 1609)

Galileo Galilei photo
Galileo Galilei photo

“What was observed by us in the third place is the nature or matter of the Milky Way itself, which, with the aid of the spyglass, may be observed so well that all the disputes that for so many generations have vexed philosophers are destroyed by visible certainty, and we are liberated from wordy arguments.”
Quòd tertio loco à nobis fuit obſeruatum, eſt ipſiuſmet LACTEI Circuli eſſentia, ſeu materies, quam Perſpicilli beneficio adeò ad ſenſum licet intueri, vt & altercationes omnes, quæ per tot ſæcula Philoſophos excrucia runt ab oculata certitudine dirimantur, nosque à verboſis dſputationibus liberemur.

Original text as reproduced in Edward Tufte, Beautiful Evidence (Cheshire, Connecticut: Graphics Press LLC, 2006), 101 (p. 3 of 4, insert between pp. 16V & 17R. Original manuscript renders the "q" in "nosque" with acute accent.)
Translation by Albert Van Helden in Sidereus Nuncius (Chicago, 1989), 62
Sidereus Nuncius (Venice, 1609)

Similar authors

Galileo Galilei photo
Galileo Galilei 70
Italian mathematician, physicist, philosopher and astronomer 1564–1642
Giordano Bruno photo
Giordano Bruno 62
Italian philosopher, mathematician and astronomer
Blaise Pascal photo
Blaise Pascal 144
French mathematician, physicist, inventor, writer, and Chri…
Isaac Newton photo
Isaac Newton 171
British physicist and mathematician and founder of modern c…
René Descartes photo
René Descartes 47
French philosopher, mathematician, and scientist
Gottfried Leibniz photo
Gottfried Leibniz 29
German mathematician and philosopher
Alphonsus Maria de' Liguori photo
Alphonsus Maria de' Liguori 2
Italian Catholic bishop, spiritual writer, composer, musici…
Carlo Goldoni photo
Carlo Goldoni 9
Italian playwright and librettist
Niccolo Machiavelli photo
Niccolo Machiavelli 130
Italian politician, Writer and Author
Claude Adrien Helvétius photo
Claude Adrien Helvétius 8
French philosopher