* Uranus: With a tilt of 97.77 degrees, Uranus is practically spinning on its side. This extreme tilt is thought to be the result of a massive collision early in the solar system's history.

* Saturn: While not as extreme as Uranus, Saturn has a significant tilt of 26.73 degrees.

Other planets also have axial tilts, but they are not as extreme as Uranus and Saturn:

* Earth: 23.44 degrees

* Mars: 25.19 degrees

* Jupiter: 3.13 degrees

* Venus: 177.36 degrees (it's almost flipped upside down)

* Mercury: 0.034 degrees (almost no tilt)

It's important to remember that axial tilt can have significant effects on a planet's climate and seasons. Uranus's extreme tilt, for example, leads to very long periods of extreme darkness and light on different parts of the planet.