Leaving Earth is a meticulously researched history of the manned space stations: Skylab, the Salyuts, Mir and the current International Space Station (ISS). They were originally intended as a step towards interplanetary travel, their development spurred on by Cold War rivalry.

Zimmerman tells the story of the space stations in chronological order, starting with the dreams of Arthur C. Clarke and Wernher von Braun, then working launch-by-launch through the Soviet and U.S. space station and shuttle programs. (Other space activities, like the Moon launches, are peripheral to the book.) He documents not only the science and the politics, but also the personalities, giving brief biographies and character sketches. At times, it can seem a little like being introduced to too many people too fast at a party, but Zimmerman is right to do it — the personalities of cosmonauts, confined together in a tiny space for months, are critical to the story.

Skylab was a scientific triumph for the USA in the early 1970s, but the Russians soon took the lead. Zimmerman tells us that since 1976, when one of their cosmonauts spent 96 days in space, the Russians have held almost every space endurance record. The author is no fan of communism but he admires the Russians’ persistence, especially compared with the failure of the USA to build the Freedom space station, which was eventually merged into the ISS project.

Zimmerman believes the only reason to build space stations is to learn how to build interplanetary spaceships. As Wernher von Braun noted 50 years ago, once in orbit it doesn’t take much additional energy to propel a vessel on its way to Mars, or anywhere else in the Solar System.