Did NASA have a distinct word to describe what the Apollo astronauts saw when they looked at out at the stars, when traveling between the Earth and the Moon? Sky does not seem right, as that word implies standing on an astronomical body.
Someone in English Language & Usage.SE suggested I ask here after the best answer, celestial sphere, was felt to be too formal and sounding like something from an ancient culture.
I'm avoiding words like firmament, heavens, vault, canopy. I'm hoping for a word that might be heard in casual conversation, or at least has a contemporary feel to it.