CBSE Class 6 General Knowledge

Unit 4: Science & Technology

Lesson: The Solar System

📘 Study Module: The Solar System

1. Introduction

The Solar System is a family of celestial bodies that revolve around the Sun. It includes planets, moons, asteroids, comets, and other objects held together by the Sun’s gravity.

2. The Sun

The Sun is a huge ball of hot gases and the center of the Solar System. It provides heat and light to all the planets. Without the Sun, life on Earth would not be possible.

3. Planets of the Solar System

There are eight planets in the Solar System. They are:

• Mercury
• Venus
• Earth
• Mars
• Jupiter
• Saturn
• Uranus
• Neptune

The planets revolve around the Sun in fixed paths called orbits.

4. Inner and Outer Planets

• Inner planets: Mercury, Venus, Earth, and Mars (rocky planets)
• Outer planets: Jupiter, Saturn, Uranus, and Neptune (gaseous planets)

5. Other Members of the Solar System

• Moons: Natural satellites that revolve around planets
• Asteroids: Small rocky bodies found mainly between Mars and Jupiter
• Comets: Icy bodies that develop a tail when they come close to the Sun
• Meteoroids: Small pieces of rock moving in space

6. Importance of the Solar System

The Solar System helps us understand Earth’s position in space. It explains day and night, seasons, and tides. Studying it also helps scientists explore space.

📝 Questions and Answers

A. Short Answer Questions

(One sentence each)

1. What is the Solar System?
   Answer: The Solar System is a group of celestial bodies that revolve around the Sun.
2. Name the center of the Solar System.
   Answer: The Sun is the center of the Solar System.
3. How many planets are there in the Solar System?
   Answer: There are eight planets in the Solar System.
4. Which planet is closest to the Sun?
   Answer: Mercury is the closest planet to the Sun.
5. Which planet is known as the Red Planet?
   Answer: Mars is known as the Red Planet.
6. Which is the largest planet?
   Answer: Jupiter is the largest planet.
7. What is Earth’s natural satellite?
   Answer: The Moon is Earth’s natural satellite.
8. What are asteroids?
   Answer: Asteroids are small rocky bodies that revolve around the Sun.
9. What is a comet?
   Answer: A comet is an icy body that forms a tail near the Sun.
10. What provides heat and light to the planets?
    Answer: The Sun provides heat and light to the planets.

B. Long Answer Questions

(3–5 sentences each)

11. Describe the Sun.
    Answer: The Sun is a massive ball of hot gases at the center of the Solar System. It provides heat and light to all planets. Its gravity keeps the Solar System together. It is essential for life on Earth.
12. Name the planets of the Solar System in order.
    Answer: The eight planets in order from the Sun are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. They revolve around the Sun in fixed paths called orbits. Each planet has unique features.
13. What are inner planets?
    Answer: Inner planets are Mercury, Venus, Earth, and Mars. They are located close to the Sun. These planets are rocky in nature. They are also called terrestrial planets.
14. What are outer planets?
    Answer: Outer planets are Jupiter, Saturn, Uranus, and Neptune. They are located far from the Sun. These planets are mostly made of gases. They are also called gas giants.
15. Explain the role of gravity in the Solar System.
    Answer: Gravity is the force that keeps planets in their orbits. The Sun’s strong gravity holds all celestial bodies together. Without gravity, planets would not revolve around the Sun. It maintains balance in the Solar System.
16. Write a short note on the Moon.
    Answer: The Moon is Earth’s only natural satellite. It revolves around the Earth. The Moon reflects sunlight and has no light of its own. It affects tides on Earth.
17. What are asteroids and where are they found?
    Answer: Asteroids are small rocky bodies. They revolve around the Sun. Most asteroids are found in the asteroid belt between Mars and Jupiter. They vary in size.
18. Describe comets.
    Answer: Comets are icy bodies made of dust and gases. They move around the Sun in long orbits. When they come close to the Sun, they form a bright tail. This tail always points away from the Sun.
19. How is Earth different from other planets?
    Answer: Earth is the only planet known to support life. It has air, water, and suitable temperature. Living organisms exist on Earth. This makes it unique.
20. Why is the study of the Solar System important?
    Answer: Studying the Solar System helps us understand Earth’s place in space. It explains natural phenomena like day and night. It also helps in space exploration. Knowledge of the Solar System improves scientific understanding.

🧠 Multiple Choice Questions (MCQs)

(With Answers and Detailed Explanations)

1. What is the center of the Solar System?
   a) Earth
   b) Moon
   c) Sun
   d) Jupiter
   Answer: c) Sun
   Explanation: The Sun is at the center of the Solar System.
2. How many planets are there?
   a) Seven
   b) Eight
   c) Nine
   d) Ten
   Answer: b) Eight
   Explanation: There are eight planets in the Solar System.
3. Which planet is closest to the Sun?
   a) Venus
   b) Earth
   c) Mercury
   d) Mars
   Answer: c) Mercury
   Explanation: Mercury is nearest to the Sun.
4. Which planet is known as the Red Planet?
   a) Venus
   b) Mars
   c) Jupiter
   d) Saturn
   Answer: b) Mars
   Explanation: Mars appears red due to iron oxide.
5. Which is the largest planet?
   a) Earth
   b) Saturn
   c) Jupiter
   d) Uranus
   Answer: c) Jupiter
   Explanation: Jupiter is the largest planet.
6. Which planet supports life?
   a) Mars
   b) Venus
   c) Earth
   d) Neptune
   Answer: c) Earth
   Explanation: Earth has conditions suitable for life.
7. What is Earth’s natural satellite?
   a) Mars
   b) Moon
   c) Sun
   d) Asteroid
   Answer: b) Moon
   Explanation: The Moon revolves around Earth.
8. What are asteroids mainly made of?
   a) Ice
   b) Gas
   c) Rock
   d) Water
   Answer: c) Rock
   Explanation: Asteroids are rocky bodies.
9. Where is the asteroid belt located?
   a) Between Earth and Mars
   b) Between Mars and Jupiter
   c) Between Jupiter and Saturn
   d) Near the Sun
   Answer: b) Between Mars and Jupiter
   Explanation: The asteroid belt lies between Mars and Jupiter.
10. Which planet is known for its rings?
    a) Mars
    b) Venus
    c) Saturn
    d) Mercury
    Answer: c) Saturn
    Explanation: Saturn has prominent rings.
11. What keeps planets in their orbits?
    a) Wind
    b) Light
    c) Gravity
    d) Heat
    Answer: c) Gravity
    Explanation: Gravity holds planets in orbit.
12. Which planets are called gas giants?
    a) Mercury and Venus
    b) Earth and Mars
    c) Jupiter and Saturn
    d) Mercury and Mars
    Answer: c) Jupiter and Saturn
    Explanation: They are large and gaseous.
13. Comets are made mainly of ______.
    a) Rocks and dust
    b) Ice and dust
    c) Metal
    d) Water only
    Answer: b) Ice and dust
    Explanation: Comets are icy bodies.
14. Which planet is farthest from the Sun?
    a) Uranus
    b) Saturn
    c) Neptune
    d) Jupiter
    Answer: c) Neptune
    Explanation: Neptune is the farthest planet.
15. What is an orbit?
    a) A planet
    b) A star
    c) The path of a planet
    d) A satellite
    Answer: c) The path of a planet
    Explanation: Planets move in orbits around the Sun.
16. Which planet is known as Earth’s twin?
    a) Mars
    b) Venus
    c) Jupiter
    d) Mercury
    Answer: b) Venus
    Explanation: Venus is similar in size to Earth.
17. What causes day and night on Earth?
    a) Revolution
    b) Rotation
    c) Gravity
    d) Tides
    Answer: b) Rotation
    Explanation: Earth’s rotation causes day and night.
18. Which celestial body has its own light?
    a) Moon
    b) Earth
    c) Sun
    d) Mars
    Answer: c) Sun
    Explanation: The Sun produces its own light.
19. What is a meteoroid?
    a) A planet
    b) A satellite
    c) A small rocky object in space
    d) A gas giant
    Answer: c) A small rocky object in space
    Explanation: Meteoroids are small space rocks.
20. Why is the Sun important to Earth?
    a) It causes earthquakes
    b) It controls gravity only
    c) It provides heat and light
    d) It forms asteroids
    Answer: c) It provides heat and light
    Explanation: Life depends on the Sun’s heat and light.

✅ End of Lesson

Prepared strictly in accordance with the NCERT syllabus and CBSE Class 6 examination standards.