DAYTIME STAR

According to ex-Cambridge astronomer Mitton's solidly factual, non-mathematical account, about one fifth of all astronomers are studying the controlled nuclear explosion that is our sun. He begins with a look at Earth's ancient sunworshipping cultures, and moves through historical studies (including Newton who, investigating the solar spectrum, discovered infrared radiation by accident) to the modern, bent-space Einsteinian viewpoint. Mitton (Exploring the Galaxies, 1977; The Crab Nebula, 1979) describes the various instruments used to probe the sun's mysteries and explains how they work, from the giant land-based radio telescopes to the various satellites and Skylab (for a detailed account see John A. Eddy's The New Sun: The Solar Results from Skylab, 1979). Next Milton shows what these instruments have detected, and what it means in terms of solar structure, stability, energy generation, lifespan, and evolution. There's a section on solar neutrinos (including hypotheses as to why the Davis experiments have failed to detect them); the solar wind (and eerie phenomena like zodiacal light and gegenschein, caused by space dust scattering sunlight); the vastly complex solar magnetic field; sunspots; and the various solar cycles. Another section explains how the sun impinges upon the Earth's atmosphere to create geomagnetic storms, disturb the van Allen belts, produce auroras, and possibly affect climate. At the close, Mitton presents brief arguments for the development of both nuclear and solar energy as the only realistic option. Not, then, for general consumption; but a useful intermediate-level addition to the solar literature-and more reliable than Mark Washburn's recent In the Light of the Sun (p. 346).