 Ida 's rotation period is 4 @.@ 63 hours , making it one of the fastest rotating asteroids yet discovered . The calculated maximum moment of inertia of a uniformly dense object the same shape as Ida coincides with the spin axis of the asteroid . This suggests that there are no major variations of density within the asteroid . Ida 's axis of rotation precesses with a period of 77 thousand years , due to the gravity of the Sun acting upon the <unk> shape of the asteroid . 
