It’s 2050. The Earth is dying, and moving to Mars seems to be the only way out for humans. A team of American astronauts begin to search on Mars. This is what the movie Red Planet begins with. Known as the Red Planet, Mars is the favorite of writers and filmmakers. Mars is the fourth planet from the Sun and the next planet beyond the Earth. Mars is the only planet whose surface can be seen from the Earth. It is about half size of our planet.

The surface of Mars is more like the Earth than any other planet. But it is further from the Sun than the Earth, so temperatures on Mars are much lower. Plants and animals can not live now on Mars. But many scientists still believe that life may have been on Mars long ago. On 6th August,1996, scientists discovered a piece of rock from Mars, which fell to the Earth 13,000 years ago. Ten years later, some scientists still didn’t accept that there was life on Mars. People may not be sure about life on Mars until a sample(样本) of life is brought back. Some further researches are being done in many countries.

Do you know anything about the Moon? How much do you know about it?

【小题1】? Scientists tell us so much about the Moon. So it’s easy for us to have the idea of going to the Moon. But what would it be like to really go there?

The Moon is not a friendly place. There is no air or water. There are only lots of dust (灰尘) and mountains around on it. 【小题2】. The temperature (温度) of the Moon is different from day to night. 【小题3】. But it’s very cold at night.

【小题4】 As we know, sound can only travel in the air but there is no air on the Moon.

But from the Moon, you can see our beautiful Earth. It is shining more brightly than the other stars in the dark. 【小题5】 The photos would be wonderful.

Astronauts (宇航员) may soon be going to the moon again. NASA plans to build bases (基地) there. Astronauts will not be able to take all the food they will need. So they may have to grow some of it on moon farms.

But can plants grow on the moon? Maybe. That is according to a new study. Scientists used soil (土壤) brought back from the moon. They used it to grow plants on Earth. It turned out that success could depend on where on the moon you do your planting.

In the 1960s and 1970s, NASA ran the Apollo program. It sent astronauts to the moon. In the new study, scientists used soil that astronauts collected there.

Scientists put this soil in little cups. Each cup got about a teaspoon of moon soil. Other cups got Earth soil. The scientists planted seeds (种子). They watered the soil and put the cups under growth lights.

In the Earth soil, plants grew healthy leaves. In the moon soil, plants grew leaves, too. But those plants were smaller. And they were less healthy. The older the moon soil was, the worse the plants grew.

Stephen Elardo is one of the scientists. He says it still might be possible to grow plants on the moon. The key could be finding the right place. Scientists still have much to learn. But this study brings humans one step closer to calling the moon home.

What might a moon farm look like? Tyler Jones helps us imagine it. He created a model moon farm. He also used the same kinds of plants that scientists grew in moon soil. His pictures show how moon farms might work.

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