1. What is the diameter of Mercury?

2. Which is the largest impact crater on Mercury?

3. How long does it take for Mercury to complete one orbit around the Sun?

4. How many rotations does Mercury complete on its axis for every two orbits around the Sun?

5. What is the average length of a day on Mercury?

6. What type of surface features does Mercury have?

7. What is the temperature range on Mercury?

8. What is the main component of Mercury’s thin atmosphere?

9. Which spacecraft orbited Mercury from 2011 to 2015?

10. What is the origin of Mercury’s magnetic field?

11. How many missions have been sent to study Mercury?

12. What is the name of the mission that flew by Mercury in 1974-1975?

13. Which planet is closest to Mercury?

14. Which element is present in Mercury’s atmosphere in trace amounts?

15. What is the approximate distance of Mercury from the Sun?

16. What is the main reason Mercury is unable to retain a substantial atmosphere?

17. What is the name of the largest and most prominent impact crater on Mercury?

18. How does Mercury’s surface compare to the Moon’s surface?

19. Which planet has a weaker magnetic field than Earth?

20. What valuable data and images were obtained from the MESSENGER mission?