Chapter 1: Our Earth and Our Solar System
Solved textbook questions with step-by-step explanations.
Grade 5 Q&A: Chapter 1: Our Earth and Our Solar System
Welcome to the Questions and Answers section for Grade 5 Science, Chapter 1: "Our Earth and Our Solar System." This chapter helps us understand our place in space, learning about the Sun, planets, stars, and the amazing force of gravity.
Important Questions and Answers
Q1: What are heavenly bodies? Give examples.
Answer: Heavenly bodies are all the objects we see in the sky. Examples include the Sun, the Moon, stars, and planets.
Q2: What is the difference between stars and planets?
Answer:
- Stars: They twinkle and have their own light. Example: The Sun.
- Planets: They do not twinkle and do not have their own light. They get light from stars. Example: Earth.
Q3: What is the Solar System? What is at its center?
Answer: The Solar System is made up of the Sun and all the heavenly bodies that revolve (move) around it. The **Sun** is at the center of our Solar System.
Q4: Name the eight planets in our Solar System in order from the Sun.
Answer: The eight planets in order from the Sun are:
- Mercury
- Venus
- Earth
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
Q5: What is an orbit?
Answer: An orbit is the fixed path along which a planet revolves around the Sun. Satellites also revolve around their planets in their own orbits.
Q6: What is a satellite? Give an example.
Answer: A satellite is a heavenly body that revolves around a planet. Satellites also get their light from the Sun. The **Moon** is a satellite of the Earth.
Q7: What are dwarf planets? Give an example.
Answer: Dwarf planets are smaller heavenly bodies that revolve independently around the Sun. They have their own orbits. A well-known example is **Pluto**.
Q8: What are asteroids? Where are they found?
Answer: Asteroids are many small heavenly bodies that revolve around the Sun. They are mainly found in a band between the orbits of the planets **Mars and Jupiter**.
Q9: What is the force of gravity?
Answer: The force of gravity is a force of attraction or a pull that all heavenly bodies (like Earth or the Sun) exert on other objects. It pulls things towards them.
Q10: Why do things fall down to the Earth?
Answer: Things fall down to the Earth because of the Earth's gravity. The Earth pulls everything towards its center, which is why objects always fall to the ground.
Q11: How does the Sun's gravity affect planets?
Answer: The Sun's gravity pulls on all the planets. This pull, along with the planets' tendency to move away, makes the planets keep revolving around the Sun in fixed orbits and at fixed distances.
Q12: What is 'space' or 'outer space'?
Answer: Space, or outer space, is the emptiness between and beyond the stars and planets.
Q13: Why are very powerful rockets needed to send objects into space?
Answer: Very powerful rockets are needed to send objects into space because they must overcome the Earth's strong force of gravity. Rockets burn a lot of fuel to create a huge upward force that pushes the spacecraft away from Earth.
Q14: What are astronauts?
Answer: Astronauts are scientists or people who travel in spacecraft into space for various missions.
Q15: Who was the first Indian astronaut to go into space? When?
Answer: **Rakesh Sharma** was the first Indian astronaut to go into space in 1984.
Q16: What is a man-made satellite?
Answer: A man-made satellite is a satellite built by humans and launched into space using rockets. They are put into orbit around the Earth and can stay there for many years.
Q17: List two uses of man-made satellites.
Answer: Two uses of man-made satellites are:
- Providing useful information for weather forecasting and agriculture.
- Used for telecommunication (like phone calls and internet).
- Making maps and searching for water and mineral wealth on Earth.
Q18: What was Chandrayaan-1? When was it launched?
Answer: Chandrayaan-1 was India's first spacecraft launched to the **Moon** for deeper study. It was launched by ISRO (Indian Space Research Organization) on **October 22, 2008**.
Q19: What is Mangalyaan? What was special about its mission?
Answer: Mangalyaan, also known as MOM (Mars Orbit Mission), was an important Indian space mission to the planet **Mars**. It was special because ISRO achieved this feat (reaching Mars) in its very first attempt on September 24, 2014, after launching on November 5, 2013.
Q20: Why is our Earth considered an invaluable (very precious) planet?
Answer: Our Earth is considered an invaluable planet because, so far, space scientists have not found any other planet in the universe that has life on it. It is unique in supporting life.
Q21: Which planet is nearest to the Sun?
Answer: **Mercury** is the planet nearest to the Sun.
Q22: Which planet is furthest from the Sun?
Answer: **Neptune** is the planet furthest from the Sun.
Q23: What is the main difference between a star and a planet in terms of light?
Answer: Stars have their own light and shine brightly, while planets do not have their own light. Planets reflect light from nearby stars, like the Sun.
Q24: What is the 'revolution of the Earth'?
Answer: The movement of the Earth around the Sun along its fixed path (orbit) is called the revolution of the Earth.
Q25: Name two Indian-origin astronauts (besides Rakesh Sharma).
Answer: Two Indian-origin astronauts are **Kalpana Chawala** and **Sunita Williams**.
Exercise Solutions (Based on Maharashtra Board Textbook)
Q1: Fill in the blanks.
- The Sun is a star.
- The Earth is a planet.
- The Moon is a satellite of the Earth.
- Asteroids are found between the orbits of **Mars** and **Jupiter**.
- To travel in space, the Earth's **gravitational force** has to be overcome.
Q2: Match the pairs.
| Group A | Group B |
|---|---|
| Sun | Star |
| Earth | Planet |
| Moon | Satellite |
| Pluto | Dwarf Planet |
| Mangalyaan | Mission to Mars |
Q3: Give reasons.
- Our Earth is an invaluable planet.
Answer: Our Earth is an invaluable planet because, among all the heavenly bodies known so far, it is the only planet that has life on it. It has the right conditions (like water, air, and temperature) to support living things. Therefore, we must protect its environment, as any harm to it would threaten the existence of life itself. - Rockets are needed to send objects into space.
Answer: Rockets are needed to send objects into space because of the Earth's strong force of gravity. Earth's gravity pulls everything downwards. To make an object go into space, it must be given a very strong upward push (power) to overcome this gravitational pull. Rockets are designed to do this by burning a huge amount of fuel to produce a tremendous force, allowing spacecraft to be launched into space.
Q4: Write answers to the following questions in your own words.
- What is the Solar System? Draw a diagram of our Solar System.
Answer: The Solar System is a family of heavenly bodies that includes our Sun, the eight planets that revolve around it, their satellites, dwarf planets, and asteroids. The Sun is at the center, and all these bodies move in fixed paths called orbits around it.
(Diagram: A simple diagram showing the Sun at the center. Eight planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune) revolving around the Sun in elliptical orbits. The Moon revolving around Earth. A band of asteroids between Mars and Jupiter. Pluto as a dwarf planet further out. Label all important bodies and their orbits.) - Explain the importance of man-made satellites.
Answer: 1. Man made satellites provide useful information on agriculture, environment, weather, forecasting, making maps and searching for water and mineral wealth on the earth.- 2. It is also used for telecommunication.
References
- Maharashtra State Board Science and Technology Standard Five Textbook (Latest Edition) - Chapter 1: Our Earth and Our Solar System.
- Maharashtra State Board 5th Standard Science Syllabus.
- Balbharati Science and Technology Textbook Part 1.
Additional Exercises and Solutions
1. What's the solution?
Question: One of the asteroids has fallen out of its place in the asteroid belt and is hurtling towards the sun. Our earth is in its way and there is all likelihood of a collision. What can be done to prevent this collision?
Answer: Use the shock wave to deflect it away from earth. Which means attach three large remote controlled rockets to the asteroid turning it into a large space vehicle and move it away from a dangerous collision.
2. Use your brain power!
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Question: What will happen to our solar system if the sun were to suddenly disappear?
Answer: 1. If the sun were to suddenly disappear all life forms on earth will cease, because the sun is a source of light and heat. 2. There will be complete darkness on all planets. 3. The planets will move from their orbits and may clash against each other.
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Question: Suppose you want to give your address to a friend you have on the planet Mars. How will you write your address if you want them to understand exactly where you live?
Answer: To give an address to a friend on Mars, it would need to be very specific, including cosmic coordinates. An example address might be: 'Your Name, House Number, Street Name, City, State, Country, Earth, Solar System, Orion Arm, Milky Way Galaxy, Local Group, Virgo Supercluster.'
3. In the picture below, correct the sequence of the planets from the sun.
Answer: The correct sequence of the planets from the Sun is: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
4. Who am I?
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Question: You can see me from the earth but the lighted part of me that you see changes every day.
Answer: The Moon
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Question: I have my own light. It is only from me that the planets get light and heat.
Answer: The Sun
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Question: I turn around myself, around a planet and also around a star.
Answer: A Satellite (like Earth's Moon)
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Question: I turn around myself and revolve around the sun.
Answer: A Planet
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Question: No other planet has a living world like mine.
Answer: Earth
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Question: I am the nearest star to the earth.
Answer: The Sun
5. Short Answer Questions
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Question: For what purpose are rockets used in space travel?
Answer: 1. Very powerful rockets are used to send a spacecraft into space. 2. A tremendous quantity of fuel is burnt in rockets so that spacecraft weighing thousands of tons may be launched into space.
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Question: What information do man-made satellites provide?
Answer: Man-made satellites provide a wide range of information, including weather forecasting data, agricultural insights, telecommunication services (like phone calls and internet), mapping information, and data for searching water and mineral wealth on Earth.
Activities
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Activity: Make charts about space research and display them in an exhibition.
Guidance: Students can research various aspects of space exploration, such as famous missions (e.g., Apollo, Mars rovers), space telescopes (e.g., Hubble, James Webb), different types of celestial bodies, or the history of space travel. They can then create informative charts with diagrams, images, and key facts to display in a classroom exhibition.
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Activity: Find out which planets in the solar system have satellites.
Guidance: Students should research each planet in our solar system to determine if it has natural satellites (moons). They will find that Mercury and Venus have no moons, while Earth has one, Mars has two, and Jupiter, Saturn, Uranus, and Neptune have multiple moons. This activity encourages research and understanding of planetary systems.