Dark Orbitby Carolyn Ives GilmanTor, 2015If you're going to hinge a science fiction novel on the concept of dark matter, you're going to have to get the exposition in early. In her new book Dark Orbit, Carolyn Ives Gilman has no sooner introduced her main character, opinionated iconoclast Sara Callicot, than Sara is getting a mission from a high-ranking official in the Magisterium of the Twenty Planets to investigate a distant alien world “laden” with dark matter – which said official feels the need to explain, even though Sara doesn't ask for an explanation and doesn't seem to need one:

“'Dark matter' is a misnomer; it is probably not matter. It interacts with nothing we can see, except on the largest scale. You cannot shine any light on it, because it interacts with no form of energy we know. You cannot build a detector, because it does not collide with normal particles. It casts no shadow on our world. Gravity is the only reason we know it exists, for we can detect its cumulative warping effect on the shape of space. But that tells us nothing about its nature.”

Sara is an freelance exoethnobiologist who'd “always considered herself cheerfully amoral, culturally relative to the bone,” and here she's given a mission to voyage along with a small crew to this new world, Iris; here job is to observe her crew mates and report back directly to the Magisterium, especially on the mental health and behavior of one crew member, a young relative of the official who drafted her for the mission, a woman named Thora Lassiter, who's had a mental breakdown and is embarrassing her family by claiming to hear voices.“Knowledge is our wealth, our honor, our sacrament,” Sara reflects at one point. “It drives us to give up family, home, and place in time for its sake. Would we also sacrifice our lives, like ancient martyrs longing to see the face of God? Is knowledge that sacred to us?” But as the mission arrives at Iris and begins to discover things they never imagined – including an advanced species of blind aliens possessing a strange relationship with dark matter itself – very different kinds of knowledge begin manifesting themselves to Gilman's small but well-drawn cast of explorers. Thora is the most profoundly affected by the series of mysteries Iris unveils, and in chapters drawn from her journals, we're made privy to her own doubts:

Our stories will be scientific, or politically self-serving, or marketable back home. I wonder which version of Iris will dominate. Planet of the Blind? Dangerous Eden? Innocents in Peril? They are all false, because we brought them all with us. We look at the alien and see only ourselves.

There's perhaps a little sprightly irony in those Amazing Tales-style adventure titles. Fifty or sixty years ago, the equivalent of Dark Orbit might very well have sported a title like Planet of the Blind, and in poking fun at such things Dark Orbit perhaps reveals more self-awareness of its own hackneyed provenance than some of Gilman's more overwrought passages would lead a reader to expect. In fact, those what-does-It-All-mean passages tend to jar the mood of what is in essence an old-fashioned First Contact Amazing Tale, complete with everywoman heroine, aliens who Teach Us About Ourselves, and loads of far-future science frozen at tell-tale 20^th century levels; the Magisterium's society is capable of interstellar travel, but its scientists know nothing more about dark matter and dark energy than ours do, in 2015. (Dark Orbit's pulp origins, alas, are signaled in one other tell-tale way: lazy prose. Visions of X dance in character's heads, things are crystal clear, names ring bells, people pull each other's legs, things are sufficed to say, characters didn't sign up for this, etc.)Its moments of ill-advised ambition notwithstanding, Dark Orbit is a fast-paced and grippingly written sci-fi thriller, full of interesting ideas. And if a sequel should be called Dangerous Eden, well, would that really be so bad?