The moon blew up without warning and for no apparent reason.
That's the eye-opening first sentence of Neal Stephenson's latest novel, palindromically titled Seveneves. It speaks to how much science fiction loves the what if mode of storytelling. What if the moon exploded? At first, not a whole lot. The moon splits into 7 big pieces, but thanks to gravity, they're generally in the same location and orbit, exerting the same tidal forces, and so on. That is, until the pieces of the moon start to smash into one another, splitting massive rocks into smaller chunks, leading to an exponentially increasing number of collisions. While we're not really expecting the moon to explode anytime soon, the notion of space debris colliding with other space debris, creating more debris and thus increasing likelihood of further collisions, is something NASA scientists have actually speculated about. In the novel, Stephenson calls this the "White Sky", and the smaller pieces won't stay nicely in orbit like the moon did. Within two years of the moon exploding, the Earth will be assaulted by what Stephenson calls the "Hard Rain" as all of the pieces of the moon fall to earth as bolides, releasing so much energy and heat as to make the Earth uninhabitable for thousands of years.

The human response to this news is to send as much material into orbit as possible. In a way, this is an "ark" story (a common subgenre, though it's also often relegated to backstory), but since Earth orbit is going to be crowded with moon parts, it can't be a single, giant ark. Instead, Stephenson comes up with the concept of a "cloud ark", a series of small, independent arklets that can swarm and maneuver to avoid debris. Various groupings can be made, and there's also a home-base of sorts with the International Space Station, which is somewhat larger than it is today and which is also bolted to a large iron asteroid called Amalthea (which acts as a shield for the ISS). Naturally, the cloud ark cannot accommodate more than a few thousand souls, so there's lots of Earthside wrangling and politics over who is chosen to survive, and who will remain on ground to perish in the hard rain.

You'll notice that I haven't mentioned anything about characters yet, and that's pretty illustrative about how this book reads. There is a very large cast of characters, of course, but the book seems primarily concerned with orbital mechanics and more broad sociological interactions. The depth with which Stephenson explains various elements of humanity's future home in space will no doubt turn casual readers off, but this is par for the Stephenson course. Blog readers know that I'm totally in the bag for this sort of thing, so it didn't really bother me, and while info-dumps can be frustrating when done poorly, Stephenson is a master of incorporating that sort of detail into a larger narrative. Here, the orbital mechanics are mixed fairly successfully with social mechanics and the more divisive political aspects of the cloud ark.

Depending on your point of view, this could be viewed as an intensely pessimistic view of humanity. I was actually reminded of the Battlestar Galactica television series, where people can't seem to agree with each other about anything, even when the entire race is on the brink of extinction. In some ways, it's not quite that pessimistic, and spoilers aho, humanity manages to survive, but not after some pretty harrowing and surprisingly sudden crises. More spoilers forthcoming, but the immediate takeaway is that fans of Stephenson will probably enjoy this, but like most of his novels, you probably have to have a certain mindset to enjoy it...

Individual characters feel more like chess pieces in the story's game. Sure, they have personalities (this comes into play later in the book, moreso than early on) and they're a compelling enough bunch, but their actions are severely constrained by their circumstances. This is, in many ways, the point. Living in space does not allow for many of the habits and practices we're used to here on our cushy planet, after all. Personal space, privacy, and so on are pretty severely limited. Still, the characters feel more like types than individuals. There's a science populizer called "Doc" Dubois Harris who is basically Neil Degrass Tyson. There's a miner turned roboticist named Dinah Macquarie, who is arguably the main character of the first two thirds of the book. We like both of them, and several of their surrounding characters. There's an almost cartoonishly devious political villain that emerges as well, along with her own retinue of followers. We don't like them! And there are dozens of other side characters, some becoming very important, some unceremoniously dispatched in one space disaster or another.

It's a huge novel in nearly every way, including it's physical size (another 800+ page hardcover), but also in terms of its ambition and the way Stephenson tells the story. If you think the first line is cool, the transition about two thirds of the way through the book was another pretty big surprise. At the time, humanity isn't in particularly good shape. They've fractured into two main camps, but few remain alive when they rejoin one another. On the other hand, they've finally reached a relatively safe and stable position in space to build out from, and they have enough technology to ensure the survival of the species... and then Stephenson starts a new chapter with "Five Thousand Years Later" and proceeds from there.

It's a bold choice, one of many in this book. Unfortunately, when you move the action that far forward, there's a lot to catch up with. As mentioned above, Stpehenson is a master of info-dumps, but this section of the book, in which nearly every narrative event is preceded by long and complicated digressions about how this or that piece of new orbital technology works or how this or that aspect of society works (again we get the juxtaposition of orbital and social mechanics frequently here) left even me a little impatient. It doesn't help that the events that drive that future part of the narrative seemed pretty obvious to me from the start (it's based on something from earlier in the book). Still, once the basics are established, the story gets moving on its own terms and ends strong enough.

It's just that you have to get through 5000 years of basics, which takes a while. A lot of Stephenson's ticks are noticeable here (and I don't mean that in a bad way). Stephenson loves to play with familial relationships and often returns to certain types of characters. Here, we get seven different strains of characters, such that when the story is moved 5000 years into the future, even if we don't know the new characters yet, we know their ancestors, and this gives you a little bit of an idea as to who they are. It's not a perfect, one-to-one relationship, the same way that Randy Waterhouse is distinct from Lawrence Waterhouse (in Stephenson's Cryptonomicon), but there's some underlying type that works for them both. Now, it is a bit of a hard sell to say that the 7 distinct genotypes (the eponymous seven "eves") wouldn't have interbred more in the intervening 5000 years (it is implied that this does happen, but it seems infrequent), but I can accept that the storytelling works better when you make such sharp distinctions.

It's funny, but this feels like Stephenson's most cinematic work. Many of these info-dumps and extended discussions of orbital mechanics would be much less daunting if presented visually (the book even includes a few illustrations to help you visualize what he's talking about, but they are few and far between). Alas, I'm guessing such a movie (or, more likely, TV series) would be cost prohibitive because of all the special effects required to blow up the moon, portray the white sky and hard rain, and all the arklets, let alone the far future space habitats and gigantic orbital launch devices, etc... Perhaps someday this could happen, and I think it could perhaps even surpass the book in terms of quality if done right.

I'm a total sucker for Stephenson, so it's not a surprise that I enjoyed this novel. It's not going to unseat Cryptonomicon as my favorite, but it compares favorably to his other work. I have to admit that I don't particularly agree with all of his sociological musings here, but this is interesting, exciting, and ambitious stuff, and I can't fault Stephenson for wanting to explore this fascinating territory. I know that this is an unpopular line of thought with increasingly ideological Science Fiction fans of late, but I'm actually capable of disagreeing with a work that I think is great without actually needing to doubt that greatness. This is bold, adventurous writing, and while there are plenty of valid complaints to be made, I still think this is some of the most interesting SF published in the last few years (it certainly puts the last few Hugo novel ballots to shame). You can bet this will show up on my 2016 Hugo nomination ballot.