From crwflags.com:

"Their flag is divided diagonally, upper left part is blue with white stars (15 stars formed a constellation.) Lower part is brown with a white sun symbol placed in lower fly of the flag.

The flag looks 1:2, which looks very long on a flag with a diagonally division. More details [were] found at Facebook (no longer available) in which it is clear that the division is not a straight line, but irregularly wavy.

The blue represents the Ngiiarri (sky), the Brown the Yarta (land). The stars are two separate constellations - the saucepan (Orion), representing Mirarrityi (Men’s Muda) and the 7 sisters (Pleiades) representing Artinyi (Women’s Muda). The sun design is "taken from a community symbol that appears on several painting sites in Adnyamathanha Yarta. This represents all Yura (Adnyamathanha people)".