In Canto One of his poem John Shade (the poet in VN’s novel Pale Fire, 1962) mentions the Great Bear and the Milky Way:
That's Dr. Sutton's light. That's the Great Bear.
A thousand years ago five minutes were
Equal to forty ounces of fine sand.
Outstare the stars. Infinite foretime and
Infinite aftertime: above your head
They close like giant wings, and you are dead.