What is Mars’s approximate axial tilt relative to its orbital plane?

Mars has an approximate axial tilt of 25.2 degrees relative to its orbital plane. This tilt, also called obliquity, gives Mars familiar seasonal changes because different hemispheres receive differing amounts of sunlight during its orbit.

Earth’s axial tilt is about 23.4 degrees, so Mars’s tilt is broadly similar. The comparison explains why Mars has spring, summer, autumn, and winter rather than a nearly seasonless climate. However, Martian seasons are longer because a Martian year lasts about 687 Earth days.

Mars’s orbit is much more eccentric than Earth’s. As a result, the planet’s distance from the Sun changes substantially during its year, making the seasons unequal in length and strength between the two hemispheres. Southern summers occur near Mars’s closest approach to the Sun and can therefore be especially intense.

Mars’s obliquity has also varied considerably over geological time. Those changes may have affected the stability and movement of polar ice and helped shape the planet’s climate history.