From Library Journal

The disappearance of the dinosaurs is one of the great scientific mysteries. More mystifying is the fact that a large percentage of the other species then on earth became extinct at the same time. Moreover, several other mass extinc tions appear in the fossil record. In this short book, Goldsmith describes a new theory: such events occur periodically about every 30 million years and are associated with evidence of impact cra ters on the earth's surface. These cra ters may result from comets crashing into our planet after having been driven from their orbits by an (as yet undiscov ered) companion star to the Sun. Wild as it may sound, the theory is being considered seriously by many scien tists, who are systematically searching the heavens for this hypothetical neigh bor, Nemesis. Well worth reading. BOMC/Science alternate. Harold D. Shane, Mathematics Dept., Baruch Coll., CUNY
Copyright 1985 Reed Business Information, Inc.