Some scientists believe that Mars is the planet that is more likely to support human life away from Earth.

They believe that it’s possible for humans to reach Mars by 2030. However, there are many things to prepare before this can happen.     1     Recently, scientists have sent robots to Mars to gather information about the planet.

Putting people on Mars will include planning how a person will live on Mars. At its shortest distance Mars is 55 million kilometers away from Earth.     2     And astronauts would have to stay on Mars for over 18 months before Earth and Mars are at their closest distance again. The difficulties would include how much food and other things would be needed for over two years in space and how such things would be carried.

    3     They would need to prepare both their minds and bodies for such a long trip away from Earth. NASA set up a special research building in Hawaii. A group of astronauts stayed in this research building for 366 days. During their stay, they had to deal with what they might have to deal with on Mars.     4     They had to live with each other in a very small space. They also had to deal with the problem of having lots of time with little or nothing to do. They couldn’t receive help from people outside for the whole time they were inside.

    5     There is no doubt about it.

【推荐2】①Most people have a place to call home on Earth. What about in outer space? The International Space Station(ISS) became our first “home” in space in 2000. It welcomed its first crew(队) that year, paving the way(铺平道路) for 20 years of future research.

②“You just have this impression that we’re all citizens(公民) of not a country, but of the planet,” former NASA astronaut Scott Kelly told National Geographic about working in ISS. “We’re all in this thing called humanity(人类) together.”

③Over the past 20 years, the ISS has mainly been used as a science lab, hosting 241 people from 19 countries, according to NASA. They have gone on spacewalks, done research on how space affects the human body, and even grown plants in space.

④ ▲ . For example, the station’s water purification(净化) technology has been used in poor areas to provide clean drinking water. The station also helps to warn us of natural disasters(灾难), such as earthquakes.

⑤However, after being our home in space for over 7,000 days, the station is starting to get old. It has leaked(泄漏) air a few times. Scientists think that the station can keep working until 2024. After that, scientists will bring it down to Earth. It is believed that Earth’s atmosphere(大气) will burn up most of the station. Other debris(残骸) will fall into the Pacific Ocean.

⑥In the future, space will be home to more stations like the ISS. NASA is building a space station that is smaller than the ISS near the moon. Also, China will have its own space station up in 2022.

(a. gone on spacewalks        b. provide clean water for poor areas       c. stopped earthquakes       

d. learned how space affects the human body            e. grown plants )

【推荐1】

①Over the past forty years, cars have become less polluting. Many people now drive electric cars(e-cars). And there are fewer emissions (排放) from cars. However, cities such as London and Los Angeles are still fighting air pollution. Using cleaner cars is a good step, but is this enough?

②A survey shows that more than 40 percent of the cars only have one person inside. But a car trip takes a lot of electricity (电). In the U.S., more than 60 percent of electricity still comes from fossil fuels (化石燃料). So if all of us were to use e-cars, the emissions would only be cut down by 25 percent.

③And there are other things to be worried about. Roads and other systems for cars need a lot of space. About 24 percent of London’s land (土地) has been used to build these systems. In many U.S. cities, this number can be as high as 40 percent. The World Health Organization advises cities to create at least 9㎡of green space for each person. However, in many fast-growing cities around the world, each gets less than 2㎡ because they have to use more land for roads and parking.

④So, using cleaner cars is not enough to make our cities better. In fact, cities need much fewer cars. People should have different ways to get around. Studies show that people will get out of their cars if they have more and better ways to choose. Only then will our cities become faster and greener.

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【推荐1】Wukong, Tiangong, Tianwen. Do you know where the names of Chinese space programs come from?

Wukong, the Dark Matter Particle Explorer satellite (暗物质粒子探测卫星), is named after Chinese superhero the Monkey King. According to Journey to the West, the Monkey King has a pair of sharp eyes which can tell the difference between good and evil. The Wukong satellite is just as sharp-eyed as the Monkey King to help scientists search for dark matter in space.

The name of the space station, Tiangong, means the “Heavenly Palace”. In Chinese myths, this is the home of Tian Di. Now the Tiangong space station is a home for Chinese astronauts in space. And China welcomes foreign astronauts to Tiangong so that they can work together.

Tianwen, China’s Mars missions (任务), gets its name from the poem Tianwen by Qu Yuan. Qu Yuan is a famous poet from ancient China. In Tianwen, he had the questions about the sky, stars, nature and the real world, showing his hunger for truth. Perhaps the Tianwen missions will end up answering some of Qu Yuan’s questions.

If you look into more names of Chinese space programs, you will find that they all have beautiful meanings. We, the Chinese people, have a long cherished (珍藏已久的) space dream. So the naming of Chinese space programs is taken very seriously.

【推荐2】Sending astronauts to Mars is a big challenge. Astronauts will have to ate everything they need, including food, air and water. The room inside the spaceship is too limited to hold many things. So packing a spaceship is a huge challenge for a trip to Mars.

Six astronauts on an eight-month tip to Mars will need at least 18,000 kilograms of water for drinking and washing. They’ll also need water to protect themselves from space rays which can pass right through spaceship walls and harm astronauts’ living cells. But a layer of water placed around the ship can stop the harm.

That’s a lot of water. And sending water into space is too expensive. It costs $33,000 to send one cup of water to Mars. The more you take, the more it costs. We have the technology to get to Mars, but the problem is that it’s too expensive.

But Flynn, an engineer at NASA, thinks he has a way of solving the problem. Instead of building a heavy spaceship and packing it full of stuff (物料), why not use the stuff as part of the spaceship?

Imagine a spaceship that blows up like a balloon. Inside, the walls have pockets like a big honeycomb (蜂巢). These hold lots of plastic bags filled with water, dried food and algae. All these make hard walls and great radiation (辐射) protection. And stopping radiation does not influence the food or water itself — it is safe to eat and drink. And what if the same water could be reused again and again? Flynn and his team call their packed-pocket idea Water Walls.

Making oxygen and taking away CO₂—the waste gas you breathe out—is another problem in space. “Water Walls will take away CO₂ the same way it’s done here on our Earth—with living plants,” Flynn says. Living plants make in CO₂ to make their food, and give off oxygen. “Plants are hard to grow in a spacecraft, so we use algae,” he says.

Algae are tiny plants that live in water. The algae will live in bags in the walls too, fed by human waste and sunlight, eating up CO₂ and making oxygen for the astronauts to breathe.

Flynn thinks his onboard recycling system has many advantages. He hopes it will help make flying to Mars a reality very soon.

【推荐3】NASA has been building a new telescope, called James Webb Space Telescope. Scientists think it could help them search for signs of alien life! They can watch exoplanets (外行星) with the help of the new telescope.

So far, all the exoplanets we have found are too distant to send astronauts or spaceships to them. Researchers hope the new telescope will help them find out whether there are aliens on these exoplanets!

The new telescope should be able to find out if the exoplanets have oxygen on them. Oxygen is a gas. On the earth, all animals need to breathe oxygen to live. It’s produced by plants and some bacteria (细菌). This means if there is oxygen on a planet, there might be living things as well.

These aliens probably won’t be mankind. Instead, they might be tiny bacteria. Scientists say that finding oxygen doesn’t mean there must be alien life. “We don’t know if life is the only cause of oxygen in an atmosphere (大气层),” NASA scientist Edward Schwieterman said.

The telescope can do more than search for aliens. It can study light from billions of light years away. This will help scientists learn more about what happened at the start of the universe.