PLANET EARTH

The text-and-photo volume designed to accompany a new Public Broadcasting System seven-part TV series, and handsome to behold. Science writer Weiner has also performed commendably in having to condense, survey, review and project the vast subject matter of at least seven different sciences. The book's seven chapters sport poetic titles suggestive of their contents. For starters, ""The Living Machine"" describes the planet as it is continuously being shaped and reshaped as a result of sea-floor spreading and plate tectonics. ""The Blue Planet"" reminds us that three-quarters of the earth's surface is water and is filled with wonderful new information on the wonders thereof. For example, the oceans are not level but vary as much as 30 feet in height, depending on the amount of solid mass underneath. The importance of currents, gyres, colors and the connections that link all the world's waters are described along with practical aids, such as using computer-aided color satellite pictures to locate fishing grounds. ""The Climate Puzzle"" predictably explains why forecasting is formidable--with scant hope that things will get better. ""Tales from Other Worlds"" goes beyond earth to sum up what modern telescopes and space-age exploration have revealed about the moon and sister planets. ""The Solar Sea"" closes in on the sun itself, focusing on flares, sunspots, solar winds and other phenomena that make for dynamic interactions between us and It. ""Gifts from the Earth"" hits solidly on geology with emphasis on buried treasure--iron, copper, coal, oil--and special attention to the new discoveries about upwellings of magma from cracks in the crust that are creating new habitats for life and new sources of minerals. ""Fate of the Earth"" might as well have been called the beginning and the end since it reaches back in time to speculate on the origins of life and moves ahead to ponder ecological dilemmas; it concludes ominously on a nuclear winter theme. Graceful historical notes, ancient legends, brief photo essays, the use of paintings and archeological artifacts to adorn the text further enrich the volume to make it exactly the sort of summary-survey calculated to keep nonprofessional readers (or viewers) au courant.