In "The Raven," Edgar Allan Poe wrote of "the Night's Plutonian shore."
Maybe at long last we will find out if Pluto has any Plutonian shores.
The metaphor is intended in the sense that, just as the ocean has the earth as its shore, the ocean of night must crash on the entrance to the underworld [The domain of Zeus' brother, Pluto.]
It's a beautiful image, not improved by an astronomy of which Poe could not have been aware.