"The Songs of Distant Earth" by Arthur C. Clarke (1985)
"And one day our descendants will know seas like yours, though not as wide or as deep. Water from our two worlds will mingle together, bringing life to our new home. And we will remember you with love and gratitude."
The Songs of Distant Earth was published about halfway through Clarke's career, though it was a story he'd been presenting in various forms since 1958. While substantially different from books like Childhood's End and 2001, it uses themes that will be familiar from other novels and short stories by the same author.
After our solar system perishes, the "seed ships" sent by the last (terrestrial) humans colonize several worlds in other galaxies. These seed ships carry only embryos in cold storage, and the human populations which they seed on their respective worlds develop with only a limited knowledge of their home world's history and culture.
On one of these other worlds, a watery world by the name of Thalassa, a group of humans from Earth's "last days" arrives to harvest ice for an onward journey to an unsettled planet. What results is a clash of cultures - the Thalassans, with their minimal knowledge of mankind's heritage, versus the Earthlings, a smaller group equipped with both advanced technology and a fuller knowledge of Earth's vanished culture.
It is, in other words, Mutiny on the Bounty in space. There's even a mutinous character named Fletcher, and the captain of the Earth ship's name is Bey (if not Bligh). And in case you missed the metaphor, Clarke hammers it home with all the subtlety of a jackhammer breaking up pavement. By the time you reach the book's conclusion, you'll wonder why he didn't just call it "Mutiny on the Bounty in Space" and be done with it.
In terms of style I can't fault the author. We're talking about Arthur C. Clarke, after all - a guy who at his best put most other science fiction authors to shame. But in terms of characterization this book struggles. Everyone in this book is so damn reasonable that it's hard to care about what happens to them, or why. One of the best parts of the book (death by space elevator!) is also wasted because the author hasn't spent enough time building up that particular character.
Clarke also uses the novel to talk about both homosexuality and the (non)existence of God. On the first count he succeeds admirably, and I felt glad that he could, and a later stage of life, open up about this topic. But the debates on godhood feel forced, and have no direct bearing on the plot.
In my opinion, the 1980s wasn't a good decade for science fiction, and The Songs of Distant Earth goes some distance toward refuting that opinion. Even so, it isn't nearly as good as other things written by Clarke, and the professional skill with which he wrote it doesn't make up for the fact that it's a predictable book, full of uninteresting characters.