The Bible makes this clear.

It all begins in Genesis.
The Sky is the firmament and that firmament was made for what purpose?
The purpose was to divide the waters from the waters.
I can hear your response?
The sky is just a way to divide?Yes,just to divide the waters.
So there is waters beyond the sky?
According to the Bible yes,so that leaves us with another question?
What is the night sky really if it just divides the waters from the waters?
I will expand on this post later.
Thank you for understanding me and thank you for viewing.