Hello, Moon你好，月球

In 1969， humans landed

（登录） on the moon for the first time. Now， many other countries want to go there as well. China also plans to send humans to the moon around 2030.Why？

The moon has a lot of minerals（矿物质） and other useful things. We want to find out if we can use them. The moon is our closest neighbor（邻居） in space（太空）. We can use it as a rest station（休息站）. Then， we can learn more about other planets（星球） far away in space.

The moon is about 3，476 kilometers（公里） in diameter（直径）. It is about one-fourth the size（大小） of Earth. If Earth is the size of a basketball， the moon is the size of a tennis ball.

Our moon is about 384，400 kilometers away from Earth. The total length（长度） of the Great Wall is about 21，200 kilometers.We would have to put about 18 Great Walls end to end（首尾相连） to reach the moon！

The moon has much less gravity（重力） than Earth. If you can jump 1.5 meters on Earth， you can jump about 9 meters on the moon.

It is very quiet on the moon. There is no sound there. There are a lot of grey rocks on it. The sky is always black on the moon.

China plans to send humans to the moon around——.

The sky is always——on the moon.