Astrophysics (index)about


(Axial Tilt)
(angle between an object's rotational and orbital axes)

Obliquity (or Axial Tilt) is the angle between a planet's rotational axis and its orbital axis, or equivalently between its orbital plane and its equatorial plane.

Solar system examples:

Both the Moon and Mercury have an obliquity such that the polar regions receive little sunlight.