A satellite in a 24-hour circular orbit with non-zero tilt angle (slight tilt away from the equatorial plane of Earth) will appear from the ground as if it is making a nodding motion in the sky; that

A satellite in a 24-hour circular orbit with non-zero tilt angle (slight tilt away from the equatorial plane of Earth) will appear from the ground as if it is making a nodding motion in the sky; that is, it will travel north and south each day along the same line of longitude, crossing the equator. At what intervals will it cross the equator?