Flag of Nyx
The flag of Nix or Nyx, is based upon the American Flag since Pluto was discovered by an American - Clyde Tombaugh of Illinois in 1930. In the canton is the more traditional symbol of Pluto.
Sometimes a stylized letter P with an extended bottom right dash is used. This symbol is an English bastardization of the original Greek Symbol of the 'p' sound. The P symbol in Greek is attached to the 'rr' sound, via the letter Rho.
Here is a note to remember that that P originally meant an 'r' sound before Rome hi-jacked and modified the Greek Alphabet for their own purpose. Remember to "P,P,P" your boat which means to "Row, Row, Row" your boat... because "peeing" in your boat will sink it. Also from a certain Greek point of view Pluto sort of looks like 'Rholuto.'
10th Century Painting of Nyx
Nyx was originally the Greek Goddess of night. You can see her depiction on to the left with a starry night veil and darkened skin. Goddess Nyx is a shadowy figure with astounding beauty. Her more famous siblings are Eros and Gaia. Her parent was Chaos.
The moon (or dwarf moon) dedicated to Nyx was discovered in June of 2005. And maybe the smallest moon of Pluto. Confirmation of its size and close up pictured will be 'developed' four years from now in 2015.
Flag of Nyx on the Moon of Nix or Nyx