Balrog Macula

Balrog Macula /ˈbælrɒɡ/ is the largest of the "Brass Knuckles", a series of equatorial dark regions on Pluto.

It is the largest dark equatorial feature on Pluto after Cthulhu, and is located in the middle of the leading hemisphere.

It is named after the balrogs, a race of demons in the fiction of J. R. R. Tolkien.