MCQ Detailed View

Most planets in our Solar System rotate on their axes in the same direction as they orbit the Sun. This is called prograde rotation, meaning they spin counterclockwise if viewed from above the Sun’s north pole. However, there are two exceptions: Venus and Uranus, which rotate in the opposite direction compared to most other planets. This is known as retrograde rotation.

1. 
   

   Venus:
   Venus rotates very slowly and in the opposite direction to its orbit. A single rotation on its axis takes about 243 Earth days, making its day longer than its year. Scientists believe that massive impacts or strong atmospheric interactions early in Venus’s history caused this unusual spin direction.

   
   


2. 
   

   Uranus:
   Uranus is tilted on its side by about 98 degrees, meaning it essentially rolls around the Sun. Its rotation is also retrograde, opposite to most planets. This extreme tilt is likely the result of a colossal collision with another large object during the formation of the Solar System.

   
   

The other planets listed in the options—Saturn, Jupiter, Neptune, and Mercury—all have normal prograde rotation, spinning in the same direction as they orbit the Sun.Understanding planetary rotation is crucial in astronomy because it provides clues about how planets formed and evolved. Retrograde rotation may be caused by giant impacts, gravitational interactions, or unique atmospheric dynamics. These factors help scientists reconstruct the early history of our Solar System and explain why Venus and Uranus are exceptions to the general rotation pattern.

The correct answer is therefore Venus and Uranus, the only two planets rotating opposite to the common direction of most other planets.