What do you need to make a sky?
First of all, take a big chunk of space and fill a part of it with air.
Put some stars here and there.
Add a luminous moon or sun
that darkens the brightness of the stars.
Then spread round or elongated clouds into the air.
Add to all this the perfume of spring, summer heat, the color of autumn.
And sprinkle it with the winter snow.
And you already have a heaven!
