Worlds in the Sky: Planetary Discovery from Earliest Times Through Voyager and Magellan

This informative tour of our solar system describes ``where we are now in our understanding of the planets and something of how we got here.'' After setting the stage with the development of telescopes and rockets and their use in space exploration, Sheehan ( Planets and Perception ) considers in turn the Earth's moon, each planet, the asteroid belt (the ``missing planet'' between Mars and Jupiter whose existence was indicated by a mathematical formula102 ), comets and meteors. The chapter on Venus, for example, takes us from the discovery of the planet's phasesp. 67 by Galileo to 19th-century speculation that it was Earth's ``near-identical twin'' and recent findings that the planet rotates in an opposite direction to the Earth and that its desolate surface is hotter than Mercury's. These histories of discovery are sprinkled with occasional suggestions on spotting specific bodies, such as the Saturnian satellite Hyperion (``at magnitude 14 it can just be captured in a 10-inch reflector''). Effectively blending the human quest for knowledge of the heavens with a few spurs to go out and try it oneself, this work should score well with dedicated amateur astronomers. Illustrations. Astronomy Book Club main selection. (Sept.)