Latest MCQs on Universe for Competitive Exams

11. What is the name of the first artificial satellite launched into space?
A) Explorer 1
B) Sputnik 1
C) Luna 2
D) Vanguard 1
Correct Answer: B) Sputnik 1
Explanation: Sputnik 1 was launched by the Soviet Union in 1957.

12. Which planet has the highest average surface temperature?
A) Mercury
B) Venus
C) Mars
D) Earth
Correct Answer: B) Venus
Explanation: Venus has a thick atmosphere that traps heat, making it the hottest planet.

13. What is the most abundant element in the universe?
A) Oxygen
B) Carbon
C) Hydrogen
D) Helium
Correct Answer: C) Hydrogen
Explanation: Hydrogen makes up about 75% of the universe’s elemental mass.

14. Which planet has the largest number of moons?
A) Jupiter
B) Saturn
C) Uranus
D) Neptune
Correct Answer: B) Saturn
Explanation: Saturn currently has the most confirmed moons.

15. What is the term for a system of millions or billions of stars, together with gas and dust, held together by gravity?
A) Nebula
B) Galaxy
C) Cluster
D) Supernova
Correct Answer: B) Galaxy
Explanation: A galaxy is a massive system of stars, gas, dust, and dark matter.

16. Which planet is the least dense in the solar system?
A) Jupiter
B) Saturn
C) Uranus
D) Neptune
Correct Answer: B) Saturn
Explanation: Saturn is the least dense planet; it would float in water.

17. What is the name of the process by which stars generate energy in their cores?
A) Nuclear Fission
B) Nuclear Fusion
C) Radioactive Decay
D) Chemical Reaction
Correct Answer: B) Nuclear Fusion
Explanation: Stars fuse hydrogen into helium, releasing energy.

18. Which planet is tilted on its side, causing extreme seasonal variations?
A) Uranus
B) Neptune
C) Saturn
D) Venus
Correct Answer: A) Uranus
Explanation: Uranus has an axial tilt of about 98 degrees.

19. Which planet is known as Earth’s “twin” due to its similar size and mass?
A) Mars
B) Venus
C) Mercury
D) Jupiter
Correct Answer: B) Venus
Explanation: Venus is similar in size, mass, and composition to Earth.

20. What is the name of the boundary around a black hole beyond which nothing can escape?
A) Event Horizon
B) Schwarzschild Radius
C) Singularity
D) Photon Sphere
Correct Answer: A) Event Horizon
Explanation: The event horizon is the point of no return around a black hole.