Axis Tilt Definition !free! -

, formally known as obliquity , is the angle between an object's rotational axis and a line perpendicular to its orbital plane. More commonly, it is described as the angle between the rotational axis and the orbital plane itself (the complement of the former). For a planet, this tilt determines the seasonal variation on that body.

| Planet | Axis Tilt (Obliquity) | Notable Effect | | :--- | :--- | :--- | | Mercury | ~0.03° | No seasons | | Earth | | Temperate seasons | | Mars | 25.19° | Similar seasons, but more extreme due to eccentric orbit | | Jupiter | 3.13° | Negligible seasonal variation | | Saturn | 26.73° | Pronounced seasons (7+ years each) | | Uranus | 97.77° | Extreme seasons; poles face Sun directly | axis tilt definition

For Earth, the current mean obliquity is approximately (or 23°26′). This value is not constant; it varies between 22.1° and 24.5° over a cycle of approximately 41,000 years due to gravitational perturbations from other planets (a Milankovitch cycle). , formally known as obliquity , is the