It is believed that \eta Carinae is actually a massive binary system , with the wind-wind interaction responsible for the strong X-ray emission .
Although the overall shape of the X-ray light curve can be explained by the high eccentricity of the binary orbit , other features like the asymmetry near periastron passage and the short quasi-periodic oscillations seen at those epochs , have not yet been accounted for .
In this paper we explain these features assuming that the rotation axis of \eta Carinae is not perpendicular to the orbital plane of the binary system .
As a consequence , the companion star will face \eta Carinae on the orbital plane at different latitudes for different orbital phases and , since both the mass loss rate and the wind velocity are latitude dependent , they would produce the observed asymmetries in the X-ray flux .
We were able to reproduce the main features of the X-ray light curve assuming that the rotation axis of \eta Carinae forms an angle of 29 ^ { \circ } \pm 4 ^ { \circ } with the axis of the binary orbit .
We also explained the short quasi-periodic oscillations by assuming nutation of the rotation axis , with amplitude of about 5 ^ { \circ } and period of about 22 days .
The nutation parameters , as well as the precession of the apsis , with a period of about 274 years , are consistent with what is expected from the torques induced by the companion star .