5th Standard Social Science Term-I
Our Earth
Imayan is waiting for his father after returning from school in the evening. His father is an employee in a reputed bank.
Imayan : Come Daddy! (Imayan ran and hugged his father)
Father : Imaya..... Had your snacks?
Imayan : Yes, I had! My social teacher is going to teach about Earth tomorrow. Please tell me about the Earth.
Father : Ok. I will tell you.
Imayan : How did the Earth form?
Father : Approximately 4.54 billion years ago, Solar System was a cloud of dust and gas known as Solar Nebula. Due to an explosion, these particles collapsed collapsed and began to spin having the sun at centre. The bigger particles which revolve around the sun are called planets. Thus, the planet Earth formed.
Imayan : Will you explain about Universe, Daddy?
Father : The Universe is a vast expansion of space. The Universe consists of billions of galaxies, stars, planets, dwarf planets, comets, asteroids, meteoroids and satellites. The exact size of the Universe is still unknown. Scientists believe that the Universe is still expanding outward.
Imayan : What is a Galaxy, Daddy?
Father : A Galaxy is a huge cluster of stars. Our galaxy Milky Way is one among the countless of galaxies in the Universe.
Imayan : Ok Daddy. What is Solar System?
Father : Solar System consists of the sun, the eight planets, their moons, dwarf planets, asteroids and comets. These objects re gravitationally bound.
Imayan : Very interesting Dad. Tell me about our Solar System.
Father : There are 8 planets in our Solar System. They are :
1. Mercury 5. Jupiter
2. Venus 6. Saturn
3. Earth 7. Uranus
4. Mars 8. Neptune
Imayan : Dad..... Where is our Earth in the Solar System?
Father : The Earth is the third planet from the sun and the fifth largest in Solar System.
Imayan : It is said that the Earth is rotating itself and at the same time revolving around the sun. It is true?
Father : Yes, Earth has two movements. They are :
1. Rotation
2. Revolution
Rotation
The movement of the Earth on its axis is called rotation of the Earth. Day and night are caused due to the Earth's rotation.
Revolution
The movement of the Earth around the Sun on it's axis which is tilted about 231/20 is called revolution of the Earth. Seasons are caused by Earth's revolution.
Father : Life is possible only on the Earth because of the presence of land, air and water.
Imayan : Oh! I see. What is the distance between the sun and the Earth?
Father : The distance between the sun and the Earth is nearly 150 million kilometres.
Imayan : Say some more interesting facts about planets Dad.....
Father : Mercury and Venus lie near to the sun. Next to Earth is Mars, Jupiter, Saturn, Uranus and Neptune. The planets nearer to the sun are very hot. The planets away from the sun are very cold. Mercury is the smallest planet. Jupiter is the largest planet.
Venus and Earth are called twin planets. Mars is described as the Red planet Earth is called the Blue planet. Saturn is the Ringed planet.
Imayan : Wow! Amazing! Where do we live on the Earth?
Father : We live on the surface of the Earth. It is made up of 7 continents and 5 oceans.
Imayan : 7 continents! What are they?
Father : Listen. They are :
Asia, Africa, North America, South America, Antarctica, Europe and Australia.
Imayan : Which is the biggest continent?
Father : The Asia continent, where we live is the biggest of all. Australia is the smallest one. Antarctica s a snow covered landmass.
Imayan : What are the five oceans Daddy?
Father : Pacific Ocean, Atlantic Ocean, Indian Ocean, Southern Ocean and Arctic Ocean. 71% of the Earth is covered by water and 29% is covered by landmass. About 96.5% of water is saline, 2.5% of water is fresh and 1% of water is easily accessible.
The average depth of the oceans is 3800m. The deepest point on the Ocean is Mariana Trench which is located in the Pacific Ocean.
Imayan : Thank you, Daddy. Today I have learnt a lot about the Earth from you. Now I am going to study and do my home work.
Father : Ok, Imaya. Go and study.
No comments:
Post a Comment