The Mars base has to be built, but it’s risky and dangerous, so let’s get convicts with life sentences to do it. Pretty good, but the main character has this lack of curiosity (that gets lampshaded in the story) that means I was frustrated when he wouldn’t take the next logical step. A built-in character flaw is one thing, but when that character is the reader stand-in, it’s hard not to see it as a clumsy attempt to keep the reader from figuring out what’s going on. There’s a sequel. I might read it.