The Earth In The Solar System-Class 6 Social Science Chapter 1

The Earth in the Solar System: This is the first chapter of BOSEM (Board of Secondary Education Manipur) class 6 social science. This chapter will teach you about our solar system, stars, heavenly bodies, constellations, meteors, and meteorites.

The earth in the solar system


    The Earth in the solar system

    You must have seen twinkling objects in the night sky. They are called stars. Stars have their own light and heat. The sun, which we see in the sky is also a star but you may ask Why does the sun have heating power and a star does not? This is because the sun is near to us whereas stars are far away. Some of the bright objects in the night sky do not twinkle. They are the planets. Planets have no light of their own. They are lit by the light of the sun. our earth is a planet.

    The Solar System


    The sun, the moon, the stars, and all objects in the sky are called heavenly or celestial bodies. These celestial bodies constitute the universe which is infinite Besides celestial bodies, the universe contains vast clouds of gas and dust.

    If we look carefully at the night sky, the stars make different patterns and forms. These patterns may look like animals, humans, or other things. A group of stars that form a definite pattern is called a constellation. You must have seen a group of seven stars in the northern sky that resembles a question mark (?). This constellation is called Ursa Major or the Great Bear.

    The people of ancient Greece observed different patterns of stars and gave names to them. The science of studying stars and other heavenly bodies of the universe is called Astronomy. In the olden days, people used to determine directions with the help of stars. The Pole star or Polaris indicates the north because it shines directly above the north pole of the earth.

    On a clear night, you will be able to see a large system of stars across the sky. That is our galaxy and we call it the Milky Way. In Manipuri, it is known as Ningthou Turel. A galaxy is a huge system of stars. It contains millions of stars. The solar system is a part of the Milky Way galaxy. There are billions of such galaxies in the universe.


    The Solar System

    The sun, eight planets, satellites, asteroids, comets, and meteoroids form the solar system.

    The Sun

    The sun is made up of hot, gaseous matter. we do not feel much heat from the sun because we are far away from it. Our earth is at a distance of 150 million kilometers from the sun.

    The Planets

    The sun is at the center of the solar system. The eight planets viz., Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune revolve around the sun. These planets have no light of their own. They get light and heat from the sun.

    But, where did the sun and the planets come from? It is believed that they were born out of a moving cloud of gas and dust called Nebula. The central part of the nebula became the sun. The remaining materials were condensed into balls of gas and dust. Later, they became the planet.

    Have you ever seen a spinning top? The planet spins itself like a top. They also revolve around the sun. The sun controls the movement of the planets. This controlling force is called the force of gravity.

    The path in which planets move around the sun is called orbit. The time taken to complete a full journey around the sun differs from one planet to another.


    Our Planet- The Earth

    The earth is our planet. The meaning of the word planet is wanderer. Our earth is the third nearest planet to the sun. In size, it is the fifth largest planet. The surface temperature of the earth is most suitable for the existence of life. Therefore, the earth is unique because it is the only planet where we find living beings.

    The Earth takes 365 days and 6 hours to complete a full journey around the sun. We call it one year. Your age is the number of rounds you have made around the sun.

    Like other planets, the Earth is also spherical in shape. But it is slightly flattened at the poles. Such a shape of the earth is called geoid which means earth-shaped.

    Our earth is made up of land and water. But the portion of water is much larger than the land portion. Because of this, the Earth appears blue in the photographs taken from space. So, it is called the blue planet.


    The Moon-Satellite of the earth

    Some of the heavenly bodies move around the planets. They are called satellites. Satellites also have no light of their own. They reflect the sun’s light. The moon is the only satellite of the earth.

    The moon is the brightest object in the night sky. It is also our nearest neighbor in the space. The moon is about 3,84,400 kilometers away from the earth.

    The moon spins on its own axis and it also revolves around the Earth. Every time it circles the earth once, it spins once on its axis. Thus, it takes almost the same time i.e. 27 days and 8 hours to complete both movements. Because of this, we always see the same side of the moon. It is extremely hot by day and frigid at night. The surface is covered with dust. There are mountains, valleys, and large craters on the moon. Valleys are filled with dry rocky materials.

    The moon has no light of its own. It shines because it reflects light from the sun. As the moon circles the Earth, the sun lights up different parts of it. From the earth, it looks as if the moon is changing shape. When the other side of the moon faces the sun, the side which faces the earth remains dark. So we cannot see the moon. This is called the new moon.

    Gradually, the shape grows in size from a crescent to a full moon in 15 days. The full moon slowly disappears again in another new moon. We called these changing shapes the phase of the moon.


    Asteroids

    Between the orbit of Mars and Jupiter, numerous small bodies revolve around the sun. they are thought to be the parts of some exploded planets. They are called asteroids. The largest asteroid is Ceres.


    Meteoroids

    The small pieces of rock that move around the sun are called meteoroids. When meteoroids enter the earth’s atmosphere, they get heated by friction and burn themselves. Thus we see shooting stars or meteors in the night sky. Sometimes meteors without being completely burnt fall onto the earth and they are known as meteorites. Meteorites create large craters on the earth’s surface.


    Things to Remember

    • The earth is our habitat and it was formed about 4600 million years ago.     Stars have their own light and heat. The sun is also a star. It is made up of hot, gaseous matter. It is the nearest star to the Earth.
    • Planets have no light of their own. Our earth is a planet. It is the third nearest planet to the sun.

    • A group of stars that forms a definite pattern is called a constellation. The constellation bearing the question mark of seven stars is called Ursa Major or the Great Bear.

    • The sun, the moon, the stars, and all objects in the sky are called heavenly or celestial bodies.

    • The science of studying stars and other heavenly bodies of the universe is called Astronomy.

    • The Pole star of Polaris indicates the north because it shines directly above the north pole of the earth. In the olden days before the invention of the compass needle, people used to determine directions with the help of this star.

    • The sun, the planets, satellites, asteroids, comets, and meteoroids form the solar system. The solar system is a part of the Milky Way galaxy.

    • A galaxy or the Milky Way is a huge system of stars. It contains millions of stars. It is also known as Ningthou Turel in Manipuri.

    • The sun and the planets were formed out of a moving cloud of gas and dust called a Nebula.

    • The central path of the Nebula became the sun. the remaining materials were condensed into balls of gas and dust. Later, they became planets.

    • The path in which the planets move around the sun is called orbit.

    • The earth is our planet. The earth is unique because it is the only planet where we find living beings.

    • Our earth is made up of land and water. But the portion of water is much larger than the land portion. Because of this, the Earth appears blue in the photographs taken from space. So, it is called the blue planet.

    • The Earth takes 365 days and 6 hours to complete a full journey around the sun.

    • Satellites are the heavenly bodies that move around the planet. They do not have light of their own.

    • The moon is the only satellite of the earth. The moon is about 3,84,400 kilometers away from the earth.

    • The moon spins on its own axis and it revolves around the earth. Every time it circles the earth once, it spins on its axis. The moon takes almost the same time i.e. 27 days and 8 hours to complete both movements.

    • The moon has no light of its own. It shines because it reflects light from the sun.

    • The changing shape of the moon is called the phase of the moon.

    • Asteroids are numerous small bodies that revolve around the sun. it lies between the orbit of Mars and Jupiter. They are thought to be some part of exploded planets.

    • The largest asteroid is Ceres.

    • Meteoroids are small pieces of rocks that move around the sun.

    • Meteors or shooting stars” When meteoroids enter the earth’s atmosphere, they get heated by friction and burn themselves. Thus we see meteors or shooting stars.

    • Meteorites: meteors that fall to the earth without being completely burnt are known as meteorites. Meteorites create large craters on the earth’s surface.


    Answer the following questions (Textbook)

    Q1. Which is the nearest star to the Earth?

    Ans: The sun is the nearest star to the Earth.

    Q2. What is a constellation?

    Ans: A group of stars that form a definite pattern is called a constellation.

    Q3. What is meant by orbit?

    Ans: The path in which a planet moves around the sun is called orbit.

    Q4. What are celestial bodies?

    Ans: The sun, the moon, the stars, and all the objects in the sky are called heavenly or celestial bodies. These celestial bodies constitute the infinite universe.

    Q5. How does a planet differ from a star?

    Ans: A planet does not have light of its own. It is smaller in size compared to a star and it revolves around the sun. Whereas a star has light of its own. It is bigger in size than a planet and it does not revolve around the sun.

    Q6. What are Asteroids?

    Ans: Between the orbit of Mars and Jupiter,  numerous small bodies revolve around the sun. they are thought to be part of some exploded planets. They are called Asteroids.

    Q7. Why do we always see the same side of the moon?

    Ans: The moon spins on its own axis and it also revolves around the Earth. Every time it circles the earth once, it spins once its axis. Thus, it takes almost the same time to complete both movements because of this, we always see the same side of the moon.


    Choose the correct answer.

    1. The third nearest planet to the sun is

    a) Mars

    b) Venus

    c) Mercury

    d) Earth

    Ans: Earth

    2. Which of the following has light of its own?

    a) Planet

    b) Star

    c) Moon

    d) Meteorite

    Ans: Earth

    3. Which of the following is a satellite?

    a) Sun

    b) Moon

    c) Earth

    d) Jupiter

    Ans: Moon


    Fill in the blanks:

    a) The pole star or the Polaris indicates the north

    b) A galaxy is a huge system of stars

    c) The earth is also called the blue planet

    d) The distance of the earth from the sun is 150 million kilometers


    Must Read

    📀 Chapter 2 Globe: The Latitudes And Longitudes

    📀 Chapter 3 Motion Of The Earth

    📀 Chapter 4 Maps