  Earth rotation is determined by polar motion (PM) and length of day (lod).
The excitation sources of PM are torques linked to fluid circulations
("geophysical excitations"), and those of lod to luni-solar tides
("astronomical excitations"). We explore the links between the rotations and
revolutions of planets, following Lagrange's (1853) presentation of mechanics.
The energy of a planet in motion in a central field is the sum of kinetic,
centrifugal (planet dependent) and centripetal (identical for all planets)
energies. For each planet, one can calculate a "constant of gravitation" Gp .
For the giant planets, Gp decreases as a function of aphelia. There is no such
organized behavior for the terrestrial planets. The perturbing potential of
other planets generates a small angular contribution to the displacement : this
happens to be identical to Einstein's famous formula for precession. Delays in
the planet's perihelia follow a (-5/2) power law of a. This is readily
understood in the Lagrange formalism (the centrifugal term takes over for small
distances). The telluric planets have lost energy, probably transferred to the
planets rotations. The ratio of areal velocities to rotation obeys a -5/2 power
law of a. The ratio of areal velocity to integrated period R also fits a -5/2
power dependence, implying linearity of the energy exchange between revolution
and rotation. For Einstein deformation of space-time by the Sun is the origin
of the field perturbation. For Lagrange the perturbation could only be due to
the interactions of torques. The perihelion delays, the areal velocities and
the planetary rotations display power laws of aphelia, whose behavior contrasts
with that of the kinetic moment. The areal velocity being linearly linked to
the kinetic moment of planets, this must be the level at which the transfer is
achieved.
