[4] The Leiden Aratea was created for a wealthy patron, possibly Louis the Pious or his wife Judith.

[5] The name Aratea means that it was a text derived from the lore of an astronomer whose name was Aratus of Soli (315–240bc).

[7] Scholars often view this manuscript as something that can offer an art historical perspective, but doesn't really give much accurate astronomical information regarding constellations, planets, or other natural phenomena at the time.

[9] There are a few topics that could be areas of interest to astronomers, such as the Leiden Planetary Configuration, which presents a partial heliocentric theory, that Mercury and Venus orbit the Sun.

[6] The text is written in the capitalis rustica script used by the Romans for literary manuscripts and kept by the Carolingians for secular works.

An exception to the use of the capitalis rustica script is folio 93v, the planetarium, where the routes of the planets are inscribed with quotes from Pliny's Natural History in Carolingian minuscule.

[6] Constellations, planets and the seasons are depicted in 39 full-page miniatures, all on the verso pages, with corresponding poetical descriptions on the recto.

The illustrations are probably copied from a Late Antique version of Germanicus' treatise; the subjects modeled in a "lively, illusionistic" manner typical of ancient painting.

[3] The missing constellations, Virgo Centaurus with Lupus and Corona Australis can be found in a different tenth-century copy of the Leiden Aratea located in the municipal library of Boulogne-ser-Mer.