I suppose cosmic horror elder gods like Cthulhu and such are not all that far removed from the idea of a black hole. Particularly the ones that are less involved with Earth than Cthulhu is. Nobody is ramming a black hole with a fishing boat. But the early writing on them was done at about the same time as a lot of the foundational theoretical work on black holes (not the earliest stuff but I can believe that the writers didn’t know about it)
Also, extremely pedantic note - black holes were predicted by looking at what happens in the math at extreme densities, long before black holes were actually observed in space
I suppose cosmic horror elder gods like Cthulhu and such are not all that far removed from the idea of a black hole. Particularly the ones that are less involved with Earth than Cthulhu is. Nobody is ramming a black hole with a fishing boat. But the early writing on them was done at about the same time as a lot of the foundational theoretical work on black holes (not the earliest stuff but I can believe that the writers didn’t know about it)
Also, extremely pedantic note - black holes were predicted by looking at what happens in the math at extreme densities, long before black holes were actually observed in space