Veteran science writer Bova (Welcome to Moonbase, 1987; etc.) sheds light on light in this entertaining, informal, profusely illustrated study. Light, Bova informs us, lies at the core of life itself, lightning having provided the spark that animated the primordial soup. Light provides food for plants (photosynthesis) and safety for men (the campfire and its progeny). Bova scans the role of light in medicine (as a treatment for psoriasis, vitiligo, and cancer) and body chemistry (light regulates our sex hormones); he explores the nature of light as elucidated by Galileo, Newton, Hooker, Michelson; he peers at lenses, mirrors, lasers, optical fibers, solar cells, and other devices that harness this electronragnetic wonder. Clarity rules on every page, along with a knack for finding the human connection: Bova explains why the earth's tilted axis leads us to make love at night, and he sometimes suggests little home experiments: "Go to the kitchen and hold a postage stamp alongside your refrigerator and you will see the tremendous advances that optical computers can offer." Being a Bova book, there's a plug for Star Wars; just as predictably, there's little or no examination of the role of light in religion, art, and literature. Enjoyable, informative, easy-to-read: accomplished, old-fashioned science writing in the successful Bova mode.