Some aspects of the classical three-body problem that are close or foreignto physical intuition

We propose a simple oscillator model for the reduced three-body problem to understand the stability of orbits with small eccentricity of a light plane t. It models the main short-time features for small mass ratios of the othe r bodies. These results are confronted with the exact mathematical analysis for stability for all times, and with computer simulation results for bigg er mass ratios, where chaotic features emerge. (C) 2000 American Institute of Physics. [S0022-2488(00)00806-9].