George Kelley suggested that Jack McDevitt writes the kind of science fiction I like to read: clearly written, with a good story and interesting characters. George was right, which proves, once again, that I'm an old guy, harking back to the SF of my distant youth, the kind written by Asimov, Clarke, and Heinlein. I guess there's just no getting around it, and keep off my lawn!
To tell the truth, there's not much emphasis on the science in the story. An alien artifact is discovered. it leads to another artifact, which contains gateways to other worlds. Instead of exploring those worlds Jack McDevitt chooses instead to explore ours. If such an artifact were found, what would be the effects on the economy? On religion? On politics? How would we deal with it?
This is a big-canvas novel: lots of characters popping in and out, lots of scenarios presented, lots of plot threads developed. That's not to say that McDevitt forgets the human scale of things. A couple of characters carry through the novel, and I was interested in their fates. I kind of enjoyed the idea that there were people who could actually be more powerful than the government, in a way, and I got a little kick out of their brief appearance in the novel.
The ending leaves from for a sequel, several sequels for that matter, but I don't know if there's been one. I'm sure I'd read it if I ran across it.