Evacuating the coastlines while using a nuclear explosion to deflect an Earthbound comet into the Pacific is only one of the planet-saving methods discussed by David Levy in The Quest for Comets (Oxford University Press, £7.99, ISBN 0 19286181 6). Others include steering it into Earth orbit or warning world leaders how to differentiate between a nuclear strike and a comet impact.
Levy half of the amateur team that discovered the Jupiter-striking Comet Shoemaker-Levy 9, has written an entertaining book full of his fascination with comets (he has spotted 19 so far). How to discover a comet, and the prospects for comets producing life and extinguishing it are among the goodies in a book which should inspire others to follow his lead.
