Odyssey Two by Arthur C Clarke.

⭐️⭐️⭐️⭐️⭐️ A really good sequel to 2001. Obviously, it takes place 9 years after the first novel. The mission now is to find out what went wrong with the Discovery and Hal. A Russian led expedition (with some American guests) is sent to recover it and investigate. The story starts with the planning of the mission, which is followed by the trip. The writing is entertaining and interesting. Some hard science here and there, some exploration of the characters (not too much, this is not a strength of the book), but what is really interesting is the crew's discussions and speculations about what they expect to find and their thoughts when they actually find something. And they find many other things than the Discovery, which are connected to a bigger truth so interesting it is worth 10 stars. The story was so exciting to read, I was sent back to 2001 (book and movie) on many occasions, remembering Dave Bowman and Hal 9000, and that final epic scene with the space monolith. In this novel, we learn a bit more about the monolith, but we don't get all the answers. We are left wanting for more, and there are 2 more books left in the saga.