We know that the Earth we live on goes around the Sun and that the Sun is a yellow star. We know that stars give light and that they can be blue, white, orange and red. 【小题1】

We know that stars are born, stars get older, and then stars die. As the star gets older, the middle of the star gets very hot and the star gets bigger. This star is now called a red giant. It is one of the biggest stars. 【小题2】 When it explodes the star dies. This big explosion is called a supernova. A supernova makes a very bright light. It is a billion times brighter than the Sun!

When a giant star has blown up, sometimes the core can be crushed. 【小题3】 Around the black hole, stars and dust (尘土) can spin, like water down a plug hole. Then the black hole will suck them in. What goes into the black hole cannot come out again.

We know that out there in space, there are small stars that spin very, very fast. 【小题4】 Some people said these flashing lights were aliens, but we know they are not.

【小题5】 There are millions and millions of stars, but how many, no one knows. No one has been in a black hole, so no one can tell what it is like inside.

Many people want to find out new things about the stars above. There will always be some things we know and some things we don’t. Little kids everywhere sing...

Twinkle, twinkle, little star,

how I wonder what you are.

The Earth goes around the Sun, and the Moon goes around the Earth. When our part of the Earth turns to the Sun, it’s the day. When our part of the Earth turns away from the Sun, it is the night.

In the universe, there is the sun, the moon, the earth and many stars. Through our geography lessons, we know the earth goes around the sun, and the moon goes round the earth. We have day and night because the earth keeps turning all the time. When our part of the earth turns to the sun, it is day. When our part of the earth turns away from the sun, it is night. The other part of the earth is always contrary.

Just because the moon is closer to the earth than the sun, it looks much bigger than the sun. Big things will look smaller when they are further, and small things also look bigger when they are nearer.

The sun is big enough to give out very strong light. The moon can’t give any light at all, but it looks quite bright, too. Why? In fact, the light from the moon comes from the sun. The moon looks much bigger and brighter than the stars. But in fact, the stars are much bigger and brighter than the moon. They look smaller than the moon also because they are further away from the earth.

Earth is so important because living things and people can only live on the earth. And some countries have sent astronauts to the space to learn more about the universe. At 9:00 a.m. on October 15th, 2003, Chinese astronaut Yang Liwei was sent up to space. He stayed there for 21 hours. It was the first time for Chinese to get into space.