How to Kill an Asteroid: The Real Science of Planetary Defense

Journalist Andrews (Super Volcanoes) serves up a rollicking study of scientific efforts to prevent asteroids from striking Earth. The narrative chronicles the development and successful execution of the Double Asteroid Redirection Test, a mission that changed the orbit of the small asteroid Dimorphos by crashing a van-size spacecraft into it in 2022. Andrews describes the technical wizardry that went into making the spacecraft (it would travel too far from Earth to pilot manually, so it was outfitted with an automated guidance system adapted from ballistic missiles) and offers a tense firsthand account of what it was like inside Johns Hopkins University’s Applied Physics Laboratory, which partnered with NASA on the mission, during the countdown to impact (“Some people were rigid as stone; others vacillated as if affected by an earthquake”). Discussions of what Hollywood gets wrong about doomsday scenarios amuse, as when Andrews explains that using an uncrewed spacecraft to deliver nukes for detonation on an asteroid’s surface would have made more sense than the manned drilling missions in Armageddon and Deep Impact. Andrews’s sharp eye for detail captures the expertise and eccentricity of scientists involved in the DART mission, such as when he notes that the larger asteroid Dimorphos orbited was sometimes depicted as the Death Star in simulations. It’s a surprisingly fun report on averting catastrophe. Photos. (Oct.)