Newton's N -body problem studies how heavenly bodies move in settings where the dynamics are dictated by Newton's law of motion. Basing his text on his CBMS lectures of June 2002, Saari explores this fascinating discipline, which addresses such phenomena as the weird behavior of the F-ring of Saturn. Saari starts by assuming few people have any background in this area, giving an introduction and background to each chapter, including unanswered research questions. He begins with the strange and chaotic behaviors of Mars, Mercury, and Saturn, then proceeds to central configurations and finding them, and real and imaginary collisions, closing with a lively examination of the idea of proof. Annotation ©2005 Book News, Inc., Portland, OR (booknews.com)