There are many deserts (沙漠) on the earth. And the following are some facts you may find interesting.

What are deserts like?

Deserts can be hot and dry places. Rain may not fall there for months or years. Some deserts are sandy and stony (多石的). Deserts can also be very windy places. The wind can change the shape of the deserts. It moves sand around from place to place.

Temperatures in the desert can vary enormously(非常). During the daytime, the temperature may reach 40℃ even in the shade (阴凉处). At night, deserts can become very cold. In winter there may even be a frost (霜冻) in the early morning.

Living in the desert

The camel is sometimes called "the ship of the desert". It stores food in its hump (驼峰) and can go for days without water. It has large feet which help it not to fall into the soft sand. Its long eyelashes (睫毛) keep out the sand during sandstorms.

An oasis is an area of the desert where water may be found. The water may be in pools or under the ground. People and animals visit an oasis for water and food. Plants grow at an oasis. Some farmers are able to grow crops here.

The Arabian Desert

The Arabian Desert lies between the Red Sea and the Arabian Gulf. In some parts of the desert, it is too hot for people to live. Oil was discovered under parts of the desert and in the Arabian Gulf. This oil has made some countries in the area very rich. Much of the money has been spent building fine cities with lovely parks and lakes, and people live a comfortable life there.

Every year, millions of birds are killed or hurt when they fly into buildings. Why does this happen?  Birds are flying into windows and tall buildings that are all covered by glass.

Many birds fly from one place to another. Most of the time, they live in the wild, such as forests and wetlands.  They might see small trees and flowers inside a window and want to rest on these plants. The birds do not know there is glass between them and the plants.  

Some birds fly at night. They use the moon and stars to help guide them in the right direction. Tall buildings with lights on at night can confuse（迷惑）the birds.  The birds see the light, but they cannot tell that the light is coming from inside a building. They fly toward the light and crash into a building. On many mornings, there might be several dead birds lying on the ground.

  Many office buildings now turn off their lights at night. This helps reduce the number of birds that fly into buildings and it also helps save energy.

Can anyone be an astronaut?

Of course not. You don't have to have a science degree but most astronauts do. Most of them are pilots too. Life in a spaceship is hard so you must have a healthy body and mind. You need to be easy-going, patient, and helpful to spend so much time in a small space with other people.

What's the training like?

People have to train for a year to learn how to stay healthy and safe. They practise space walking and living in zero gravity （重力）. They train in difficult conditions to learn how to solve problems and to work in a team. Everyday tasks like eating, washing and sleeping can be difficult on a spaceship. There is no running water so you have to wash with wet tissues; it's hard to enjoy the dry food that astronauts have to eat. And to sleep you must cover your eyes because the sun rises every 90 minutes on the International Space Station. You also have to tie yourself to something so you don't fly away!

What health problems do astronauts have?

Life in zero gravity causes changes to our bodies. Bones and muscles （肌肉）become thin and weak so you must do a lot of exercise in space to stay fit and to help the heart move blood around your body. Astronauts often get backache because you grow in space—up to 8 centimeters! It's also common to have headaches and to feel sick, especially at the beginning. You must have vitamins to take the place of fresh fruit and vegetables. But you don't have to put on sun cream because space suits protect your skin（皮肤）.

Are you still interested?

So now you know. If you want to go to space, study hard, learn to fly and take care of your body and mind.