[Verginius Rufus]

Apparently Caelus doesn't amount to much--a learned translation found in a couple of Latin works (in Ennius and in Cicero's treatise on the nature of the gods), probably not something that meant anything to an average Roman...no cult associated with him. Even Ouranos doesn't seem to matter very much to the Greeks--a figure in Hesiod's Theogony but not a god that people gave much attention to.

[Harmless Teddy Bear]

Yeah they named it for the most obscure god they could find.

Why not Quirinus?