Final answer:
Uranus has an extreme 98° tilt in its rotation axis, likely due to an early solar system collision, leading to prolonged 42-year periods of seasonal light and darkness at its poles.
Step-by-step explanation:
The rotation axis of Uranus is unusual because it is tipped over by approximately 98°, which is almost parallel to the plane of its orbit.
The giant planet rotates on its side, making its seasons extremely dramatic compared to other planets in the solar system. One possible explanation for Uranus's unique axial tilt is that it may have been caused by a collision with a large planetary body during the early formation of the solar system.
This collision theory is supported by the fact that such an impact could have provided the necessary force to knock Uranus into its peculiar rotational stance. The strange tilt creates extreme seasons on Uranus, where each pole gets about 42 years of continuous sunlight or darkness at a time, depending on where the planet is in its orbit around the Sun.