Both in the Quæstio and the Paradiso Dante notes how stars differ, not only in their brightness or “magnitude,” but also in the quality of their light, by which he probably means their colour:—
“Videmus in eo [sc. cœlum stellatum] differentiam in magnitudine stellarum et in luce.”[273]
“Lumi, li quali nel quale e nel quanto Notar si posson di diversi volti.”[274]
It seems as if it were the beauty and the movement of the starry sky as a whole which appealed to Dante, rather than the distinguishing of special stars and constellations. Those which he mentions are almost all either in the zodiac, and used to denote the hour, the season, or the position of one of the seven planets; or else they are near one of the poles and illustrate the circumpolar motion.
All the zodiacal constellations are mentioned except Virgo and Sagittarius. Besides the ordinary names of “Ariete,” “Libra,” etc., Aries is called “il Montone;”[275] Gemini “il segno che segue il Tauro,” “gli eterni Gemelli,” and “il bel nido di Leda,”[276] in reference to the mother of Castor and Pollux, its two brightest stars; Libra is “le Bilance”;[277] Scorpio “il freddo animale”;[278] Capricornus is “il Capra del ciel”;[279] and Pisces “la celeste Lasca.”[280]
In one place Castor and Pollux are mentioned, but merely as a synonym for the whole constellation of Gemini.[281] “Il petto del Leone ardente”[282] is perhaps Cor Leonis, the Heart of the Lion, for this is the name given to Regulus by both Ptolemy and Alfraganus. The “Maggior Fortuna”[283] of Purg. xix. 4, is a group of stars belonging to the two constellations of Aquarius and Pisces, in which the geomancers, who told fortunes by means of certain points traced at random, thought they saw a special series of these points,-:::..
It is generally agreed that the “gemme” of Purg. ix. 4, “poste in figura del freddo animale, Che con la coda percote la gente,”[284] are some stars of Scorpio which were shining on the eastern horizon just before the moon rose on the first night in the Island of Purgatory.
The zodiacal constellations in general are spoken of as “all the lights of his [the sun’s] path:” “Tutti i lumi della sua strada.” (Par. xxvi. 121, 122).
The pole star is described as the point of the axle round which the first sphere revolves.[285] The first sphere (or wheel, as it is called, with reference to its circling motion) is here the Primum Mobile, which was thought to cause the diurnal motion. This unique position gains for the pole star the name of “the star,” as for instance in Conv. III. v. 84, 85, where Dante says that a man standing at the north pole would have “la stella” directly over his head. And in Paradise he hears a voice among the spirits which makes him turn in its direction as the needle turns to the star—
“Voce, che l’ago alla stella Parer mi fece in volgermi al suo dove.”[286]