Periodic and quasi-periodic attractors of the spin-orbit dynamics of Mercury
by
Prof.Guido Gentile(Università di Roma Tre)
→
Europe/Rome
Aula Amaldi (Dipartimento di Fisica - Ed. G. Marconi)
Aula Amaldi
Dipartimento di Fisica - Ed. G. Marconi
Description
Mercury is entrapped in a 3:2 resonance: it rotates on its axis three times
for every two revolutions it makes around the Sun. The mathematical model commonly used
to study the problem proved not to be entirely convincing, because of the expression used for the tidal torque. Only recently, a model for the tidal torque has been proposed which has
the advantage of being more realistic and providing a higher probability of capture
into the 3:2 resonance. A drawback of the model is that the function describing the tidal torque appears as a superposition of peaks, so that both analytical and numerical computations are rather delicate. We shall present numerical and analytical results, which provide evidence that the librations of Mercury's spin in the 3:2 resonance are quasi-periodic in time, so that the very concept of resonance should be revisited.
