Solar System
NCERT Solution:
How does a planet differ from a star?
Answer:
| Difference Between Star and Planet | |
|---|---|
| Star | Planet |
| Is huge in size. | Much smaller in size. |
| Emits its own light. | Planet does not have its own light. |
| Does not revolve around any other celestial body. | Revolves around a star. |
| Stars twinkle. | Planets do not twinkle. |
What is meant by the ‘Solar System’?
Answer:The system formed by the sun, eight planets, satellites, asteroids and various other celestial bodies is called the Solar System. The sun is at the centre of the solar system.
Name all the planets according to their distance from the sun.
Answer: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
Why is the Earth called a unique planet?
Answer: Earth is the only known planet where life exists. Earth has the right conditions for supporting life. Water and air are available on earth and they are essential for life. Earth has the right temperature for living beings. Hence, the Earth is called a unique planet.
Why do we see only one side of the moon always?
Answer: The moon takes same number of days to make a revolution and a rotation. Due to this, only one face of moon is visible to us.
What is the Universe?
Answer: All existing matter and space (when taken as a whole) is considered as universe. All the celestial bodies come under the universe.
Tick correct answer:
The planet known as the “Earth’s Twin” is
- Jupiter
- Saturn
- Venus
Answer: (c) Venus
Which is the third nearest planet to the sun?
- Venus
- Earth
- Mercury
Answer: (b) Earth
All the planets move around the sun in a
- Circular path
- Rectangular path
- Elongated path
Answer: (c) Elongated path
The Pole Star indicates the direction to the
- South
- North
- East
Answer: (b) North
Asteroids are found between the orbits of
- Saturn and Jupiter
- Mars and Jupiter
- The Earth and Mars
Answer: (b) Mars and Jupiter
Fill in the blanks
- A group of ________ forming various patterns is called a ________.
Answer: stars, constellation - A huge system of stars is called________.
Answer: galaxy - ________is the closest celestial body to our earth.
Answer: moon - ________is the third nearest planet to the sun.
Answer: earth - Planets do not have their own________ and ___________________.
Answer: heat, light
EXTRA QUESTIONS
What is a celestial body?
Answer: The sun, the moon, planets, stars and other bodies in the universe are called celestial bodies.
What do you understand by star?
Answer: Some celestial bodies are very big and hot. They are made up of gases. They have their own heat and light. A celestial body which emits its own heat and light is called a star.
What is a constellation?
Answer: In the night sky, you can see different patterns formed by groups of stars. Such a pattern of stars is called constellation.
What do you understand by planet?
Answer: Some celestial bodies keep on moving around a star. They are called planets. A planet does not have its own light.
What is a satellite?
Answer: Some celestial bodies keep on moving around a planet. They are called satellites.
Write some uses of man-made satellites.
Answer: Some Uses of Man-made Satellites:
- For sending signals for television and telephone.
- For sending pictures of the earth.
- For sending data about climate. Scientists use this data to make weather predictions.
Write a brief note on the sun.
Answer: The sun is at the centre of the solar system. It is huge in size. It is made of hot gases. The sun provides the pulling force which binds the members of the solar family. The sun is very hot but we do not feel its heat because we are very far away from the sun. In fact, the distance between the sun and the earth is 150 million km.
What are asteroids?
Answer: There are numerous tiny bodies which move around the sun. These are present between the orbits of Jupiter and Mars. These are called asteroids.