I can't even classify this as Science Fiction... this is Engineering Fiction. Eng-Fi, is that a thing? It should be.

Anyway, I ate it up: an alt-history take on how the US might've gotten to Mars in the 80s if it had taken that direction right after Apollo, instead of the Shuttle and Space Station and Hubble and the variety of planetary probes we've built instead. And Baxter doesn't sell this as a unequivocally better direction, either -- the story's not that simple-minded, not at all.

Also, space geeks might enjoy this animation of the proposed vehicle methodology: http://www.youtube.com/watch?v=rrbvM5HuQRE