[Verginius Rufus]

Nebula is cognate with Greek nephele (as in Aristophanes' Nephelokokkygia, Cloud-cuckoo-land), and I presume with the Russian word nebo meaning "sky."

Is that esoteric enough?

[Night Hides Not]

Is that esoteric enough?

Enough so that Aristophanes likely got his ass kicked whi;e partying at the Temple of Knossos in Crete.