Analysis of the orbital motion of the Earth, the Moon and other planets and their satellites led to the discovery that all bodies in the Solar System are moving with the first cosmic velocity of their protoparents. The mean orbital velocity of each planet is equal to the first cosmic velocity of the Protosun, the radius of which is equal to the semi-major axis of the planet’s orbit. The same applies for the planets’ satellites.  All the small planets, comets, other bodies and the Sun itself follow this law, a finding that has also been proven by astronomical observations. The theoretical solutions based on the Jacobi dynamics explain the process of the system creation and decay, as well as the nature of Kepler’s laws.