A star is a big ball of hot, glowing (shining/ shimmering) gas.
Stars are born from swirling (spinning) clouds of gas and dust. There are stars that have exploded (burst) and stars that are just being born.
1) Hydrogen 2) Helium
Stars come in different colours. They can be; red, orange, yellow, white or blue. The colour of a star depends on how hot the star is. The coolest stars are reddish and the hottest stars are bluish.
Most of the stars are million times bigger than the Earth.
Stars in the sky look brighter. Stars can produce their own light. They are bright shining objects. So they can twinkle in the sky.
Stars don’t go away in the day time. As the sky gets brighter, the stars seem to get dimmer.
Stars are places where we cannot live, because heat is so great that no living being cannot live there.
Sun is a star. It is a big ball of hot, glowing (shining/ shimmering) gas. There are many stars in the sky bigger than the Sun. But in our solar system the biggest star is the Sun. Sun is also called Solar.
1) Hydrogen 2) Helium
Our Sun is a yellow star.
Sun is shaped like a sphere.
1) Sun is huge compared to Earth. It is over a million times bigger than the Earth. Sun looks small only because it is far away from us.
E.g. – If the Sun were hollow, a million Earths could fit inside it.
2) Sun is small compared to other stars. Many stars are much bigger than Sun. Sun looks bigger than the other stars because it is much nearer to us. So Sun is only a small star.
Sun is about 150 million kilometers away from the Earth. Other stars are much further away than this.
Our Sun is about 4.6 billion years old.
To study about the Sun easily, first we divide it into two parts as follows.
1) The surface of the Sun.
2) The core of Sun ( The centre of Sun)
The surface of the Sun is made up of white, hot gases like hydrogen and helium. The surface of Sun is never still. Great fountains (way of spraying) of glowing gases shoot out from it. The temperature at the surface of Sun is about 6000°C.
Deep inside the Sun, nuclear reactions are taking place all the time. These nuclear reactions produce Sun’s heat and light. The temperature at the centre of the Sun is about 16 million °C.
Sun is very important to us. Even ancient people knew the Sun was very important. They thought the Sun was a god. Following are some of the importance of the Sun.