<Li> An inclination of exactly 90 ° is a polar orbit, in which the spacecraft passes over the north and south poles of the planet . </Li> <Li> An inclination greater than 90 ° and less than 180 ° is a retrograde orbit . </Li> <Li> An inclination of exactly 180 ° is a retrograde equatorial orbit . </Li> <P> For impact - generated moons of terrestrial planets not too far from their star, with a large planet--moon distance, the orbital planes of moons tend to be aligned with the planet's orbit around the star due to tides from the star, but if the planet--moon distance is small, it may be inclined . For gas giants, the orbits of moons tend to be aligned with the giant planet's equator, because these formed in circumplanetary disks . </P>

What do you mean by the inclination of the earth's axis