Solar System - Practice Test 5

Attempt the quiz above first, then review every question with its correct answer and a short explanation below.

1. Q1.Which mission was India's first interplanetary mission?

   • A.Chandrayaan-1
   • B.Mangalyaan (MOM)✓ Correct Answer
   • C.Aditya-L1
   • D.Gaganyaan

   Explanation: Mars Orbiter Mission (Mangalyaan) launched in 2013 was India's first.

2. Q2.The 'Cassini' mission explored which planet?

   • A.Jupiter
   • B.Saturn✓ Correct Answer
   • C.Mars
   • D.Pluto

   Explanation: The Cassini spacecraft studied Saturn and its moons.

3. Q3.Which planet has the most circular orbit?

   • A.Mercury
   • B.Venus✓ Correct Answer
   • C.Earth
   • D.Mars

   Explanation: Venus has the least eccentric (most circular) orbit.

4. Q4.Which planet has the most eccentric (elliptical) orbit?

   • A.Mercury✓ Correct Answer
   • B.Venus
   • C.Earth
   • D.Neptune

   Explanation: Mercury has the most eccentric orbit of the eight planets.

5. Q5.The point in an orbit closest to the Earth is called:

   • A.Apogee
   • B.Perigee✓ Correct Answer
   • C.Aphelion
   • D.Perihelion

   Explanation: Perigee refers to the closest point in an orbit around Earth.

6. Q6.What is the primary component of Saturn's rings?

   • A.Rock
   • B.Water Ice✓ Correct Answer
   • C.Dust
   • D.Gas

   Explanation: Saturn's rings are 99.9% pure water ice.

7. Q7.The 'Galilean Moons' belong to which planet?

   • A.Saturn
   • B.Jupiter✓ Correct Answer
   • C.Uranus
   • D.Mars

   Explanation: The four large moons of Jupiter (Io, Europa, Ganymede, Callisto) discovered by Galileo.

8. Q8.Europa, a moon likely to have a subsurface ocean, orbits:

   • A.Saturn
   • B.Jupiter✓ Correct Answer
   • C.Neptune
   • D.Mars

   Explanation: Europa is a moon of Jupiter.

9. Q9.Which planet is the smallest gas giant?

   • A.Jupiter
   • B.Saturn
   • C.Uranus
   • D.Neptune✓ Correct Answer

   Explanation: Neptune is the smallest of the four gas giants by diameter (though more massive than Uranus).

10. Q10.The Sun contains what percentage of the Solar System's total mass?

    • A.50%
    • B.75%
    • C.90%
    • D.99.8%✓ Correct Answer

    Explanation: The Sun contains about 99.8% of the total mass of the Solar System.

11. Q11.Which is the first planet discovered with the use of a telescope?

    • A.Neptune
    • B.Uranus✓ Correct Answer
    • C.Pluto
    • D.Saturn

    Explanation: Uranus was the first planet discovered by telescope in 1781.

12. Q12.Which planet revolves opposite to the direction of its rotation?

    • A.No planet✓ Correct Answer
    • B.Venus
    • C.Uranus
    • D.Pluto

    Explanation: Planets revolve and rotate in the same direction (counter-clockwise) usually, except Venus/Uranus rotate retrograde but still revolve counter-clockwise.

13. Q13.The hypothetical boundary of the solar system where the Sun's influence ends is:

    • A.Kuiper Belt
    • B.Heliopause✓ Correct Answer
    • C.Oort Cloud
    • D.Magnetosphere

    Explanation: The Heliopause is the boundary where the solar wind is stopped by the interstellar medium.

14. Q14.Which planet is 1.5 AU away from the Sun?

    • A.Venus
    • B.Earth
    • C.Mars✓ Correct Answer
    • D.Jupiter

    Explanation: Mars orbits at an average distance of about 1.5 AU.

15. Q15.Which planet has the largest volcano?

    • A.Earth
    • B.Mars✓ Correct Answer
    • C.Venus
    • D.Mercury

    Explanation: Mars hosts Olympus Mons.

16. Q16.Which planet has a canyon system 'Valles Marineris'?

    • A.Mars✓ Correct Answer
    • B.Earth
    • C.Venus
    • D.Mercury

    Explanation: Valles Marineris on Mars is a grand canyon system much larger than Earth's Grand Canyon.

17. Q17.The time period of a geostationary satellite is:

    • A.12 hours
    • B.24 hours✓ Correct Answer
    • C.48 hours
    • D.365 days

    Explanation: It matches Earth's rotation period, appearing stationary.

18. Q18.Which planet has 'Polar Ice Caps' that grow and shrink with seasons?

    • A.Mercury
    • B.Venus
    • C.Mars✓ Correct Answer
    • D.Jupiter

    Explanation: Mars has visible polar ice caps made of water and dry ice.

19. Q19.Which is the only planet not named after a Greek or Roman deity?

    • A.Uranus
    • B.Neptune
    • C.Earth✓ Correct Answer
    • D.Saturn

    Explanation: Earth is an English/Germanic name, unlike the others.

20. Q20.Which dwarf planet rotates so fast it is shaped like a football (ellipsoid)?

    • A.Pluto
    • B.Eris
    • C.Haumea✓ Correct Answer
    • D.Makemake

    Explanation: Haumea rotates every 4 hours, elongating its shape.