The planet Aos distantly orbits the doomed luminous blue god-star Eta Car or Tiānshè and the red Wolf–Rayet star Cul in the Homunculus Nebula. Eta Car is a massive star situated approximately 8000 light-years from Earth in the Carina Arm of the galaxy. It is over 100 times the mass of Sol and more than a million times more luminous.
The explosion of Eta Car as a hypernova is eminent and cyclical bursts of stellar wind and radiation blast Aos, destroying civilizations and ending Aeons. The planet Aos is protected only by the dense clouds of nebular dust and debris which preferentially absorb blue light, causing the sky of Aos to appear reddish. Seven nearby ejecta blobs hang in the sky like small suns. The people of Aos laconically await their fiery deaths.