  Cassini states correspond to equilibria of the spin axis of a body when its
orbit is perturbed. They were initially described for satellites, but the spin
axis of stars and planets undergoing strong dissipation can also evolve into
some equilibria. For small satellites, the rotational angular momentum is
usually much smaller than the total angular momentum, so classical methods for
finding Cassini states rely on this approximation. Here we present a more
general approach, which is valid for the secular quadrupolar non-restricted
problem with spin. Our method is still valid when the precession rate and the
mutual inclination of the orbits are not constant. Therefore, it can be used to
study stars with close-in companions, or planets with heavy satellites, like
the Earth-Moon system.
