the day/daytime sky

[joham]

But since starry nights are not too common in Central Europe, I became interested in the daytime sky as well. ... Compared with the regularity of the night sky, the daytime sky undergoes dramatic changes: clouds change shape as they ...


Can we also say 'the day sky' (opposite to 'the night sky')? And how about the noon/noontime sky?
Thank you in advance.

[joham]

I looked up these words in my dictionaries, and found:

day nursery/care
day student/pupil/school/girl/boy
day room
day return/trip
day job

daytime phone number
daytime television

And I googled in googlebooks and found:
What are the things found in the day sky and in the night sky?
Sometimes people are surprised to see the moon in the daytime sky, and they think something has gone wrong!

Are both 'the day sky' and 'the daytime sky' good English with no difference?

Thank you again in advance.

[Rover_KE]

The daytime sky is fine by me.

The day sky is not colloquial - at least in BE.

Rover