  We answer the question whether, when forming constellations in the night sky,
people in astronomical cultures around the world and through time consistently
imagined and assigned the same symbolism to the same (type of) star group.
Evidence of semantic parallels has so far been anecdotal. We use two
complementary definitions for a star group: (1) a star group in a fixed region
of the sky (regardless of its exact star composition), and (2) a star group
with a particular shape and brightness (regardless of its location in the sky).
Over a dataset of 2003 constellations from 82 astronomical cultures, we find
many semantic parallels which are likely naturally induced by the shape and
composition of the star pattern. In certain cultural regions, geometric and
group symbols are perceived consistently over small and uniformly bright star
groups, naturalistic humanoids in large star groups with non-linear minimum
spanning tree (MST) and stars inside the convex hull, and reptiles in star
groups with low aspect ratio or linear MST. These naturally induced semantics,
seemingly endogenous to certain sky patterns, show that there are universal
(rather than learnt) patterns behind forming and naming constellations.
