Published online by Cambridge University Press: 07 August 2017
The secular equations which were used to exhibit the chaotic behaviour of the solar system (Laskar, 1989) are established here in a Hamiltonian framework. The integration of the former secular equations over 400 Myr showed that the two resonant arguments and given in (Laskar, 1990) present both transitions from libration to circulation. During the circulation of the first argument, temporary libration of the argument is observed, revealing resonance overlap beetween these two resonances, which explains the existence of a large chaotic zone for the motion of the solar system.