The image of Illapa drawing rain from the Milky Way belongs to a much richer Andean tradition of reading the night sky that modern archaeoastronomers, notably Gary Urton in his studies of Quechua sky lore, have documented in detail among Andean communities into the present day. Rather than reading constellations only from patterns of bright stars in the way familiar from Western astronomy, Andean sky-watchers also identify shapes in the dark patches, the areas of interstellar dust that block the Milky Way's light, tracing out figures such as Yacana, a celestial llama, along with a fox, a toad, a serpent and other animals understood to move across the sky through the year, with Yacana in particular closely associated with water, fertility and the well-being of actual llama herds on earth, since the animal was believed to descend at night to drink from earthly springs and rivers before returning to its place in the sky.
This dark-cloud constellation tradition gives a fuller cosmological context to Illapa's own water jar filled from the Milky Way, since the same stretch of sky that Andean communities read as a great celestial river was simultaneously populated with these animal-shaped dark patches understood to be actively involved in the movement of water between heaven and earth, Illapa's thunder and lightning representing the dramatic, sudden release of that water as rain and storm, and Yacana and the other dark-cloud figures representing its quieter, ongoing circulation.
The persistence of this sky-reading tradition among contemporary Quechua and Aymara communities situates Illapa's mythology within a living way of relating to the night sky rather than treating the god's celestial water jar as an isolated poetic image preserved only in colonial-era chronicle.