Space Invaders: How Robotic Spacecraft Explore the Solar System is a popular-science book that takes readers behind the scenes of robotic space exploration. Rather than concentrating on astronauts or a single famous mission, Michel van Pelt explains how an unmanned spacecraft is conceived, designed, constructed, tested, launched, operated and eventually used to collect scientific information from distant worlds.

The book begins with the foundations of space exploration, including rockets, satellites and the early exploration of the Moon, before moving into the process of creating a robotic spacecraft. Van Pelt explains the engineering decisions involved in designing a probe and examines its major systems, including power, communications, structures, thermal control, attitude control, propulsion, data handling and mechanisms.

A particularly useful feature is its explanation of what happens before and after launch. The book discusses spacecraft assembly, clean-room procedures, planetary protection, vibration testing, antenna testing, software testing and launch preparation. It then explores the instruments carried by probes and how those instruments collect information about planets, moons and other bodies in the Solar System.

Van Pelt writes for a general audience rather than only aerospace specialists. Technical concepts such as orbits, propulsion and spacecraft design are introduced in an accessible manner, while still providing enough engineering detail to make the book valuable to students and readers with a serious interest in space technology.