You never feel as if you get to know any one person properly and it's tricky keeping them straight in your head. Fascinating because, given the material and Koppel's access to it, how could it be anything else?
She starts with the wives of the Mercury 7, the first pilots chosen to be what fellow pilot Chuck Yeager famously described as "spam in a can".
Overnight these women went from being ordinary housewives on military bases to fabulous astrowives who took tea with celebrities such as Jackie Kennedy and made the cover of Life magazine.
To the outside world they were presented as paragons of American womanhood - patriotic domestic goddesses. It was their job to be groomed to the hilt and smile bravely as the men they loved were blasted off in rockets.
They had more money and perks than they had ever dreamed of, but also an intense and relentless pressure.
Beside the very real fear their husbands might not make it back to earth, there were the stressful press conferences and the intrusive lenses of photographers, the effort of being the perfect wife to the perfect astronaut, the strain on their relationships, the long separations and the space groupies - known as Cape Cookies - eager to get into their husbands' silver suits.
Friendship kept them going. The astrowives formed a support network, relying on each other for coffee, cigarettes and company.
That bond has endured and, as Koppel discovered, to this day many of the women still wear a golden whistle charm round their wrists as a symbol to call and come when needed.
As the programme expanded for the Gemini and Apollo launches, new wives appeared on the scene and the space race notched up fatalities.
Koppel does a fine job of capturing the thrills and tensions in the lives of the women the astronauts left behind on Earth and the book is packed with colourful stories and fascinating titbits.
Also included are terrific candid photographs of wives with beehives at splashdown parties that help capture both the era and the atmosphere.
The Astronaut Wives Club deserved to be written but I kept wishing Koppel had focused on just a few of the women - perhaps glamorous Rene Carpenter, tragic Betty Grissom and gracious Annie Glenn - to produce a less scrappy, more satisfying story about this remarkable time and the individuals who lived through it.