An editor asked Asimov to write a story after discussing with him a quotation from Ralph Waldo Emerson:
'If the stars should appear one night in a thousand years, how would men believe and adore, and preserve for many generations the remembrance of the city of God which had been shown!'
The resulting story, also called Nightfall (
Nightfall and Other Stories) was first published in 1941.
The novel-length adaptation was a collaboration between Asimov and Silverberg. It doesn't really add much to the story, what it does add is character development. As another reviewer pointed out, it's missing 'that special Asimov touch', particularly in the Daybreak section. However, it's still an incredibly imaginative and thought-provoking read.
Having re-read it multiple times over the past 15 years or so, it's still one of my all-time favourites.