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Chapter 12. Beyond Earth

Chapter Review

Chapter 12. Beyond Earth

This chapter introduces students to the fascinating world beyond our planet. It explains stars, constellations, the Solar System, planets, natural satellites, asteroids, comets, the Milky Way Galaxy, and the Universe. Students also learn how ancient people used stars for navigation and how modern astronomy helps us understand space. This chapter develops scientific curiosity while connecting everyday observations of the night sky with basic astronomical concepts. :contentReference[oaicite:0]{index=0}

Chapter Review

This chapter review is designed for quick revision before examinations. It highlights the most important concepts, definitions, scientific facts, and key terms in simple CBSE-friendly language.

Introduction

Whenever we look at the clear night sky, we see thousands of shining stars. Some appear brighter than others, while some form interesting patterns. For thousands of years, people observed the sky to understand directions, seasons, and time. Today, scientists use advanced telescopes and spacecraft to explore the vast universe beyond Earth.

Our Earth is only a tiny part of an enormous universe. It revolves around the Sun, which is just one of billions of stars in our galaxy. Beyond our Solar System lie countless galaxies containing millions and billions of stars.

What is Astronomy?

Astronomy is the branch of science that studies celestial objects such as stars, planets, moons, galaxies, comets, asteroids, and the universe.

Astronomers use telescopes, satellites, and space missions to understand how these objects are formed, move, and interact with one another.

Stars

A star is a huge ball of extremely hot gases that produces its own heat and light. Stars shine because energy is continuously released inside them.

The Sun is the nearest star to Earth and is the main source of energy for our planet. Other stars appear much smaller because they are extremely far away.

Key Facts

• Stars produce their own light.
• They appear to twinkle when viewed from Earth.
• Some stars are brighter than others.
• The Sun is also a star.
• Distance makes stars appear tiny.

Constellations

Groups of stars that appear to form recognizable patterns are called constellations. These patterns helped ancient travelers and sailors identify directions before modern navigation systems were invented. Today, astronomers divide the entire sky into 88 officially recognized constellations. :contentReference[oaicite:1]{index=1}

Important Constellations

• Orion (The Hunter)
• Taurus
• Canis Major
• Ursa Major (Big Dipper)
• Ursa Minor (Little Dipper)

Pole Star (Polaris)

The Pole Star appears almost fixed in the northern sky. It helps people identify the north direction and has been used for navigation for centuries.

In India, the Pole Star is popularly known as Dhruva Tara.

Night Sky Watching

Observing the night sky is easier in places where there is very little light pollution. Villages, mountains, and dark open areas provide excellent conditions for observing stars and constellations.

Good Conditions for Sky Watching

• Clear sky
• No clouds
• Dark surroundings
• Less artificial light
• Open area away from buildings

Modern mobile applications and star maps also help identify stars, constellations, and planets. :contentReference[oaicite:2]{index=2}

Light Pollution

Light pollution is caused by excessive artificial lighting at night. It reduces the visibility of stars and affects astronomical observations.

Effects of Light Pollution

• Fewer stars become visible.
• Difficult to identify constellations.
• Affects scientific observations.
• Reduces the beauty of the night sky.

The Sun

The Sun is the centre of our Solar System. It is an extremely hot sphere of gases that provides heat and light to all the planets.

Importance of the Sun

• Main source of energy.
• Supports life on Earth.
• Drives weather and climate.
• Helps plants prepare food.
• Controls the water cycle.

Important Facts

• Distance from Earth ≈ 150 million km.
• This distance is called one Astronomical Unit (AU).
• The Sun is nearly 100 times larger than Earth in diameter.

The Solar System

The Solar System consists of the Sun and all the objects that revolve around it. These include planets, moons, asteroids, comets, and several smaller bodies.

Main Members of the Solar System

• Sun
• Eight planets
• Natural satellites
• Asteroids
• Comets
• Dwarf planets

Eight Planets

The planets are arranged according to their distance from the Sun.

Order	Planet
1	Mercury
2	Venus
3	Earth
4	Mars
5	Jupiter
6	Saturn
7	Uranus
8	Neptune

The first four planets are rocky planets, while the last four are giant planets mainly made of gases and ice. :contentReference[oaicite:3]{index=3}

Special Planets

• Earth – The Blue Planet.
• Mars – The Red Planet.
• Venus – Morning Star or Evening Star (although it is not actually a star).
• Jupiter – Largest planet.
• Saturn – Famous for its beautiful rings.

Planets vs Stars

Stars	Planets
Produce their own light.	Reflect sunlight.
Twinkle.	Usually do not twinkle.
Very hot.	Much cooler.
Made mainly of hot gases.	Rocky or gaseous bodies.

Important Terms

• Astronomy – Study of celestial objects.
• Star – Self-luminous celestial body.
• Constellation – Pattern of stars.
• Pole Star – Star indicating the north direction.
• Solar System – Sun and all objects revolving around it.
• Planet – Celestial body revolving around the Sun.
• Astronomical Unit (AU) – Average distance between Earth and the Sun.
• Light Pollution – Excess artificial light reducing visibility of stars.

Quick Revision Points

• The Sun is the nearest star to Earth.
• Stars produce their own light.
• Constellations help identify regions of the sky.
• The Pole Star helps locate the north direction.
• Dark skies are best for observing stars.
• Light pollution reduces visibility of celestial objects.
• The Solar System contains eight planets.
• Mercury is the nearest planet to the Sun.
• Neptune is the farthest planet from the Sun.
• Earth is the only known planet supporting life.

Chapter 12. Beyond Earth

NCERT Textbook Exercise With Answers

Chapter 12. Beyond Earth

The following NCERT Solutions are prepared according to the latest NCERT Curiosity Science Grade 6 textbook and the latest CBSE pattern. The answers are written in simple, original, and student-friendly language to help learners understand the concepts clearly and prepare effectively for examinations.

NCERT Textbook Exercise

Read each question carefully and understand the explanation given with the answers.

Question 1. Match the following.

Column I	Column II
(i) Satellite of Earth	(d) Moon
(ii) Red Planet	(c) Mars
(iii) Constellation	(a) Orion
(iv) Planet commonly called the Evening Star	(b) Venus

Answer:

Column I	Correct Match
(i)	(d) Moon
(ii)	(c) Mars
(iii)	(a) Orion
(iv)	(b) Venus

Question 2 (i). Solve the following riddle.

My first alphabet is in MAN but not in CAN.
My second alphabet is in ACE and also in FAN.
My third alphabet is in RAT and not in CAT.
My fourth alphabet is in SUN but not in FUN.
I am a planet that moves around the Sun.

Answer:

Mars

Question 2 (ii). Make two similar riddles by yourself.

Answer (Sample):

Riddle 1

My first letter is in STAR but not in CAR.
My second letter is in VENUS and EARTH.
My third letter is in LIGHT but not in NIGHT.
I shine in the daytime and give energy to Earth.
Who am I?

Answer: Sun

Riddle 2

I do not produce my own light.
I move around the Earth.
You can see different phases of me.
Who am I?

Answer: Moon

Question 3. Which of the following is not a member of our Solar System?

(i) Sirius
(ii) Comets
(iii) Asteroids
(iv) Pluto

Answer:

Sirius is not a member of our Solar System. It is a distant star outside our Solar System. :contentReference[oaicite:0]{index=0}

Question 4. Which of the following is not a planet of the Sun?

(i) Sirius
(ii) Mercury
(iii) Saturn
(iv) Earth

Answer:

Sirius is not a planet. It is a star.

Question 5. Which of the following statements are correct?

• (a) Stars produce their own light.
• (b) Planets produce their own light.
• (c) Planets shine because they reflect sunlight.
• (d) The Sun is a star.

Answer:

Correct statements are (a), (c), and (d).

Explanation:

• Stars are self-luminous.
• Planets do not produce their own light.
• Planets are visible because they reflect sunlight.
• The Sun is the nearest star to Earth.

Question 6. Why do stars appear to twinkle while planets usually do not?

Answer:

Stars are extremely far away from Earth. Their light passes through different layers of the atmosphere, causing it to bend continuously. This makes stars appear to twinkle. Planets are much closer than stars and appear as tiny discs, so their light is steadier and they usually do not twinkle.

Question 7. Why is the Pole Star important?

Answer:

The Pole Star appears almost fixed in the northern sky. It helps people identify the north direction and has been used for navigation by travellers and sailors for centuries. :contentReference[oaicite:1]{index=1}

Question 8. Draw lines to connect the stars for Orion and label the star Sirius.

Answer:

Students should draw the Orion constellation by joining the stars as shown in the textbook and label Sirius as the brightest nearby star. :contentReference[oaicite:2]{index=2}

Question 9. From Earth, stars disappear at dawn and appear again at dusk. Why?

Answer:

During the daytime, sunlight is scattered by Earth's atmosphere, making the sky very bright. Because of this bright sky, the light from distant stars cannot be seen. At night, when the Sun is below the horizon, the sky becomes dark and the stars become visible again. :contentReference[oaicite:3]{index=3}

Question 10. Observe the Big Dipper several times during the night. Does it appear to move?

Answer:

Yes. The Big Dipper appears to move around the Pole Star during the night. This apparent movement is caused by the rotation of the Earth on its axis. Students should make observations at different times and draw labelled sketches in their notebooks. :contentReference[oaicite:4]{index=4}

Question 11. Think about the night sky and write a poem or a short story.

Answer (Sample):

The night sky is filled with countless shining stars. Every star tells a silent story of the vast universe. The Moon lights up the darkness, while the planets slowly travel around the Sun. Looking at the sky reminds us that Earth is only a tiny part of a magnificent universe full of mysteries waiting to be explored.

Chapter 12. Beyond Earth

Extra Questions Examination Based

Chapter 12. Beyond Earth

The following important questions are prepared according to the latest NCERT Curiosity textbook and the latest CBSE competency-based pattern. These questions cover concepts, observations, applications, and higher-order thinking skills related to stars, planets, the Solar System, galaxies, and the Universe.

Important Questions with Answers

Practice these questions regularly to strengthen your conceptual understanding and improve your performance in examinations.

One Mark Questions

Question 1. What is a star?

Answer: A star is a huge celestial body that produces its own heat and light.

Question 2. Which is the nearest star to Earth?

Answer: The Sun.

Question 3. What is a constellation?

Answer: A constellation is a group of stars that appears to form a recognizable pattern in the sky.

Question 4. Name Earth's natural satellite.

Answer: The Moon.

Question 5. Which planet is known as the Red Planet?

Answer: Mars.

Question 6. Which planet is famous for its rings?

Answer: Saturn.

Question 7. Which is the largest planet in the Solar System?

Answer: Jupiter.

Question 8. What is the name of our galaxy?

Answer: The Milky Way Galaxy.

Question 9. What is an asteroid?

Answer: An asteroid is a small rocky object that revolves around the Sun.

Question 10. What is the Pole Star also known as in India?

Answer: Dhruva Tara.

Two Mark Questions

Question 1. Differentiate between stars and planets.

Answer:

Stars	Planets
Produce their own light.	Reflect the light of the Sun.
Usually twinkle.	Usually do not twinkle.

Question 2. Why is the Pole Star important?

Answer:

The Pole Star appears almost fixed in the northern sky and helps travellers and sailors identify the north direction.

Question 3. Why is the Sun important for life on Earth?

Answer:

• Provides heat and light.
• Supplies energy for photosynthesis.
• Supports weather, seasons, and the water cycle.

Question 4. What are asteroids?

Answer:

Asteroids are small rocky bodies that revolve around the Sun. Most of them are found in the asteroid belt between Mars and Jupiter.

Question 5. What is a galaxy?

Answer:

A galaxy is a vast collection of millions or billions of stars, planets, gas, and dust held together by gravity.

Three Mark Questions

Question 1. Explain the main members of the Solar System.

Answer:

The Solar System consists of the Sun, eight planets, their natural satellites, dwarf planets, asteroids, comets, and several smaller celestial objects. All these bodies revolve around the Sun due to its gravitational pull.

Question 2. Why do stars appear to twinkle?

Answer:

The light coming from distant stars passes through different layers of Earth's atmosphere. Continuous changes in air density bend the light in different directions, making stars appear to twinkle.

Question 3. Describe the importance of the Sun.

Answer:

• It is the nearest star to Earth.
• It provides heat and light.
• It is the ultimate source of energy.
• It supports life through photosynthesis, weather, and the water cycle.

Question 4. Why is the Milky Way Galaxy important?

Answer:

The Milky Way Galaxy is our home galaxy. It contains millions to billions of stars, including our Sun, and our Solar System is a small part of it.

Question 5. Why is a dark sky better for observing stars?

Answer:

Artificial lights produce light pollution, making faint stars difficult to see. Dark locations away from city lights provide a much clearer view of stars and constellations.

Long Answer Questions

Question 1. Explain the Solar System with the help of its main members.

Answer:

The Solar System consists of the Sun at the centre and all the celestial bodies revolving around it. These include the eight planets, their natural satellites, dwarf planets, asteroids, comets, meteoroids, and other small objects. Mercury is the nearest planet to the Sun, while Neptune is the farthest. The Sun's gravitational force keeps all these objects moving in their respective orbits.

Question 2. Describe the differences between stars and planets with suitable examples.

Answer:

Stars are self-luminous celestial bodies that produce their own heat and light. They appear to twinkle because of atmospheric effects. The Sun and Sirius are examples of stars. Planets do not produce their own light but reflect sunlight. They revolve around the Sun in fixed orbits and usually do not twinkle. Earth, Mars, Jupiter, and Saturn are examples of planets.

Question 3. Explain the importance of constellations and the Pole Star.

Answer:

Constellations are groups of stars forming recognizable patterns in the night sky. They helped ancient people identify seasons and directions. The Pole Star remains almost fixed in the northern sky and has been used for navigation by travellers and sailors for centuries. Modern astronomy also uses constellations to identify different regions of the sky.

Question 4. Explain the Milky Way Galaxy and the Universe.

Answer:

The Milky Way is the galaxy that contains our Solar System. It has millions to billions of stars along with gas and dust. Beyond the Milky Way, there are countless other galaxies spread across the Universe. Scientists continue to study these galaxies to understand the origin and evolution of the Universe.

Question 5. Describe the importance of astronomy in modern life.

Answer:

Astronomy helps us understand celestial objects and the Universe. It has contributed to the development of satellites, GPS, weather forecasting, communication systems, and space exploration. Studying astronomy also increases scientific curiosity and expands our knowledge about the origin and future of the Universe.

Chapter 12. Beyond Earth

40 Important MCQs with Answers

Chapter 12. Beyond Earth

The following multiple-choice questions are prepared according to the latest NCERT Curiosity textbook and the latest CBSE competency-based pattern. They cover important concepts related to stars, planets, constellations, the Solar System, galaxies, and space exploration.

40 Important MCQs with Answer Key

Choose the correct answer for each question.

1. Which is the nearest star to Earth?

(A) Sirius (B) Sun (C) Polaris (D) Vega

2. The Sun is a

(A) Planet (B) Satellite (C) Star (D) Asteroid

3. Which planet is known as the Red Planet?

(A) Venus (B) Mars (C) Jupiter (D) Mercury

4. Which is the largest planet in the Solar System?

(A) Saturn (B) Earth (C) Jupiter (D) Neptune

5. Which planet is famous for its beautiful rings?

(A) Mars (B) Saturn (C) Uranus (D) Venus

6. Which is the natural satellite of Earth?

(A) Mars (B) Moon (C) Venus (D) Europa

7. Planets shine because they

(A) Produce their own light (B) Reflect sunlight (C) Produce electricity (D) Burn gases

8. Which celestial objects produce their own light?

(A) Planets (B) Stars (C) Moons (D) Asteroids

9. Groups of stars forming recognizable patterns are called

(A) Meteors (B) Galaxies (C) Constellations (D) Satellites

10. Which constellation is also known as The Hunter?

(A) Orion (B) Ursa Major (C) Taurus (D) Scorpius

11. The Pole Star helps us find the

(A) East direction (B) West direction (C) North direction (D) South direction

12. The Pole Star is also called

(A) Sirius (B) Dhruva Tara (C) Alpha Centauri (D) Vega

13. Which planet is nearest to the Sun?

(A) Venus (B) Earth (C) Mercury (D) Mars

14. Which is the farthest planet from the Sun?

(A) Uranus (B) Neptune (C) Saturn (D) Jupiter

15. The Solar System consists of the Sun and

(A) Only planets (B) Only stars (C) All objects revolving around the Sun (D) Only moons

16. Which of the following is NOT a planet?

(A) Earth (B) Mars (C) Sirius (D) Neptune

17. Most asteroids are found between

(A) Earth and Mars (B) Mars and Jupiter (C) Jupiter and Saturn (D) Venus and Earth

18. A comet mainly consists of

(A) Hot gases only (B) Ice, dust, and rock (C) Molten iron (D) Liquid water

19. Which galaxy contains our Solar System?

(A) Andromeda Galaxy (B) Whirlpool Galaxy (C) Milky Way Galaxy (D) Sombrero Galaxy

20. The branch of science that studies celestial objects is called

(A) Biology (B) Astronomy (C) Chemistry (D) Geology

21. Stars appear to twinkle because of

(A) Earth's atmosphere (B) Clouds only (C) Rotation of planets (D) Moonlight

22. Planets usually do not twinkle because they

(A) Produce no light (B) Appear as small discs from Earth (C) Are cooler than stars (D) Never move

23. Which planet is often called the Morning Star or Evening Star?

(A) Mars (B) Venus (C) Mercury (D) Jupiter

24. The average distance between Earth and the Sun is called

(A) Light Year (B) Kilometre (C) Astronomical Unit (AU) (D) Parsec

25. Artificial lights in cities reduce the visibility of stars due to

(A) Air pollution (B) Light pollution (C) Water pollution (D) Noise pollution

26. Which place is best for observing the night sky?

(A) Busy market (B) Bright city centre (C) Dark open area (D) Inside a building

27. Which planet is known as the Blue Planet?

(A) Earth (B) Neptune (C) Uranus (D) Venus

28. Which celestial body revolves around a planet?

(A) Star (B) Satellite (C) Galaxy (D) Asteroid

29. The Moon shines because it

(A) Produces its own light (B) Reflects sunlight (C) Contains fire (D) Is made of gas

30. Which of the following is a dwarf planet?

(A) Mercury (B) Pluto (C) Venus (D) Mars

31. Which is the smallest planet in the Solar System?

(A) Mars (B) Mercury (C) Venus (D) Earth

32. Which planet supports life?

(A) Venus (B) Mars (C) Earth (D) Mercury

33. The Solar System is a part of the

(A) Milky Way Galaxy (B) Orion Nebula (C) Andromeda Galaxy (D) Universe only

34. Which of the following is NOT a member of the Solar System?

(A) Asteroid (B) Comet (C) Sirius (D) Neptune

35. Which instrument is commonly used to observe distant celestial objects?

(A) Microscope (B) Telescope (C) Periscope (D) Binocular microscope

36. Which statement is correct?

(A) Stars reflect sunlight.

(B) Planets produce their own light.

(C) The Sun is a star.

(D) The Moon is a planet.

37. Which of the following is an example of a constellation?

(A) Jupiter (B) Orion (C) Moon (D) Mars

38. Which celestial object develops a bright tail when it comes near the Sun?

(A) Asteroid (B) Comet (C) Moon (D) Planet

39. The Universe contains

(A) Only our Solar System

(B) Only the Milky Way Galaxy

(C) Countless galaxies, stars, and planets

(D) Only stars

40. The main aim of astronomy is to

(A) Study weather only

(B) Study celestial objects and the Universe

(C) Study plants

(D) Study oceans

Answer Key

1-B, 2-C, 3-B, 4-C, 5-B, 6-B, 7-B, 8-B, 9-C, 10-A,
11-C, 12-B, 13-C, 14-B, 15-C, 16-C, 17-B, 18-B, 19-C, 20-B,
21-A, 22-B, 23-B, 24-C, 25-B, 26-C, 27-A, 28-B, 29-B, 30-B,
31-B, 32-C, 33-A, 34-C, 35-B, 36-C, 37-B, 38-B, 39-C, 40-B.