Kowal drops a meteor on Washington, D.C. in the opening act of her novel. First, great way to generate some excitement (I also appreciate that she handles it with much more sensitivity than Independence Day handled the destruction of major American cities,) and second a great way to begin an alternate history story without resorting to the cliche of “this war turned out differently” that dominates the genre.

Pretty quickly Kowal pivots from the disaster (although the characters continue to see the after-effects of the Meteor and hold remembrances on Meteor Day) because that’s not what this book is about. The purpose behind the huge deviation from our timeline with a meteor impact taking out Washington, D.C.? To get the space program started earlier. The meteor hits in an alternate 1952 (Dewey is president instead of Truman,) and Elma York is a mathematician working for NACA (NASA’s precursor organization.) She survives the impact during a weekend in the Poconos with her husband, Nathaniel, an engineer who also works for NACA. Soon after the impact, Elma calculates a value for the massive amount of heat the kinetic energy from the meteor added to the Earth, and while the exact values are not revealed in the book, the expected results are startling.

Initially the soot output from uncontrollable wildfires and the impact cool the Earth’s climate for a couple years, much as volcanic eruptions have done in the recent past. After a few years though, the heat added to the Earth’s systems will tend to increase the temperature of the atmosphere, eventually to the point where life on Earth might not be possible (the numbers are a little vague here.)

People from Earth will need an escape route – and that route is into space. So the nascent space program is jump-started by a massive investment from the reformed government in Kansas City. Not only the United States, but many other nations take part in this new space program, and in the early years of its development, Elma York is a computer (the term used for mathematicians, mostly women, who did the hard work of calculation in the days before electronic and mechanical computers were reliable enough or inexpensive enough.)

The central tension of the novel comes when Elma realizes that she’d like to be an astronaut, and that the new situation, where everyone will eventually have to evacuate from Earth, demands that women are allowed to travel into space just as the men are.

Stetson Parker, the prototypical military-pilot-and-first-man-in-space, is a serious antagonist in this, as is the bureaucracy of the new U.N.-managed space agency.

A secondary struggle is Elma’s struggle with herself. Like many, she suffers from impostor syndrome, self-doubt, and a near-crippling anxiety. Her struggles with her own mind’s work to sabotage her efforts provide a running counterpoint to the successes she experiences during the story.

She also does (mostly) good work as an ally of black astronauts and pilots, whose valuable contributions are constantly devalued in the continuing Jim Crow Era of the 1950s, and while she means well, Elma finds it hard to understand and follow the struggles of those who face far more overt and violent oppression. The tone of some of these sections indicate some areas where Kowal has some difficulty successfully duplicating the voices of struggling minorities – it seems like she made it too easy on Elma.

In all, I would recommend this book – great story with great characters, and a good way of showing a more inclusive Space Race than we had in our own history. The biggest change I would make is to avoid too many puns in the private moments between Elma and her husband – it may be the relationship some people have, but it’s a little grinding on the reader after too many.