The third in the Hugo, Nebula and Locus award-winning series

The Earth is growing ever hotter, as governments clash and riots and sabotage plague the space program. The IAC's goal of getting as many people as possible off Earth before it becomes uninhabitable is under threat.

The Moon colony is still being established, but Elma York is already on her way to Mars. Her friend and fellow Lady Astronaut Nicole Wargin is thrilled to be on the pioneering mission—but less happy that her husband, the Governor of Kansas, is considering a run for President.

'The Lady Astronaut series might be set in an alternate past, but they're cutting-edge SF novels that speak volumes about the present.' –The Verge

'Kowal masters both science and historical accuracy in this alternate history adventure.' –Andy Weir

'In The Calculating Stars, Mary Robinette Kowal imagines an alternate history of spaceflight that reminds me of everything I loved about Hidden Figures.' –Cady Coleman, Astronaut

'This is what NASA never had, a heroine with attitude.' –The Wall Street Journal