Stars and Moonspots: Dante’s Astronomy

---

…if the Moon is closely examined, two things will be seen peculiar to it which are not seen in other stars: one is the shadow in it…the other is the variation in its luminosity, which shines now on one side, now on the other, according as the Sun looks upon it.

—Dante, Convivio, Book II.13

---

---

Even after Galileo directly observed the moon with the telescope, poetry continued to shape the description and representation of celestial bodies, revealing the interplay between literary imagination, artistic invention and scientific observation in Renaissance astronomical books. In his philosophical treatise, the Convivio, Dante considered astronomy to be the most “high and noble” of the sciences. Indeed, each canticle of the Comedy ends with the word “stars,” and the poem is rich with references to the position of the sun, moon, stars and planets (1). Notably, Dante dedicated almost an entire canto to discussing lunar spots (Paradiso 2) (2).

Dante’s ideas were adapted to bolster current astronomical theories and observations. Dante’s extensive scholarly engagement with the moon’s surface may have inspired Galileo to more fully explore the planet’s properties and appearance in his groundbreaking work, the Starry Messenger (3, 4). The poet’s scientific observations inspired other astronomers as well. Alessandro Piccolomini cited the Comedy in his widely-read work On the Fixed Stars (5). Piccolomini responded to Dante’s description of stellar constellations, and in particular to the influence of the stars on one’s character and disposition: For instance, Dante ascribed his poetic gifts to Gemini.

The Comedy was also cited for its linguistic ingenuity. In contrast to other scientific texts of the time, written in Latin, the Comedy was written in the Italian vernacular. By translating scientific terms and concepts into his native tongue, Dante appealed to broader audiences, and played a significant role in the development of Italian scientific terminology. Terms such as “pianeta” (planet) and “galassia” (galaxy) which appear in Galileo and Piccolomini’s works are just a few examples. This process of adaptation, citation and translation both contributed to, and was shaped by, the poet’s authority in language and the sciences.