• A. Mars
  • B. Venus
  • C. Jupiter
  • D. Mercury

💡 Need a hint?

This planet is known as the hottest of them all and is often clearly visible as the “morning star” or “evening star” in the sky. Most planets spin in the same direction, but one is the big exception.

✅ View the answer

The correct answer is B. Venus.

Almost all planets in our solar system rotate counter-clockwise on their own axis (as seen from west to east), but Venus does the exact opposite. We call this retrograde rotation. On Venus, you would see the sun rise in the west and set in the east. And as if that weren’t strange enough, Venus also rotates extremely slowly — so slowly that one day on Venus is longer than an entire year on Venus.

📚 More background information

Venus is sometimes called Earth’s “twin sister,” because the two planets are close to each other in size and mass. But that is where the similarities quickly end. Venus’s atmosphere is extremely dense, consists largely of carbon dioxide, and has clouds that reflect sunlight so strongly that the planet has stood out for centuries as a bright point of light just after sunset or just before sunrise.

Why does Venus rotate the other way? Scientists honestly still don’t know exactly. One widely cited explanation is an ancient collision with a large object that once reversed the direction of rotation. Another idea is that the combination of the thick atmosphere and the gravitational pull of the sun gradually flipped the rotation over millions of years. Both theories have their supporters, and the debate is ongoing.

In pub quizzes, this is a reliable trick question. Many people guess Mars or Mercury, simply because those names sound familiar. The planets that do rotate clockwise can be counted on one hand, and Venus is the best-known example that crops up in quizzes. If you tuck this fact away in your head before the next quiz night, there’s a good chance it will earn you points, because most people get this one wrong.