【推荐1】Are we humans alone in space? Scientists have been working on this question for a long time. And recently, new discoveries offer more hope that some form of life existed on Mars in the past, and perhaps is still there at present.

According to a new report in the book Science, the Mars Explorer Curiosity has found more methane (甲烷) in the Martian air. It might suggest the possibility of life.

During the last 20 months, Curiosity has found methane many times, and four of them, it tested at a level 10 times higher than usual. “It’s a great increase,” said Christopher Webster, the lead scientist.

This new finding has made a big change. In September 2013, Curiosity found almost no sign of methane on Mars. Just weeks later, however, the explorer picked up the gas.

Methane is also found in Earth’s air, and comes from animal and plant life, as well as from the environment itself. If there’s methane in Mars’ air, where is it coming from? Scientists aren’t sure.

“There are many possible sources, such as actions between water and rock,” guessed Sushil, a scientist of the Curiosity team.

But the scientists have left the possibility open that microbes (微生物) could be the methane’s source. Also, for the first time, Curiosity found other organisms (有机物) in the rocks of Mars. Organisms are thought to be the basis to form life. Scientists aren’t sure where these organisms come from. They could either have formed on Mars or landed on Mars by meteorites (陨石).

For the next three years, Curiosity will keep looking for more organisms in rocks and exploring Mars.

①What is it like to exercise in space? Simple things can be harder in microgravity (微重力), while difficult tasks might suddenly be a breeze. A video on Tuesday shows that Zhai Zhigang, one of the astronauts of Shenzhou XIII spaceship, is practicing tai chi with flowing (流畅的) movements.

②The three astronauts, Zhai Zhigang, Wang Yaping and Ye Guangfu have been in space for about two months since they began their six-month mission (任务) to build the space station on October 16th. Chinese people have long been wondering what really goes on inside the space station. While people were still surprised by Wang Yaping’s zero-gravity hairstyle, Zhai showed his “flying” skill and was clearly very good at it.

③ ※ The tradition of Chinese astronauts practicing tai chi started in 2012 when the country’s Shenzhou IX astronaut Liu Yang first did so in space and called the experience comfortable. Before returning from the Shenzhou XII mission in September, astronaut Nie Haisheng also practiced tai chi in the Tianhe core module during an Earth-space video call with Hong Kong youths.

④For space travelers, doing exercise is important. They must exercise to counter (抵消) the gravity-free conditions because the experience of “muscle and bone loss (肌肉和骨质流失)” in space will influence their health and ability to work in the long term.

⑤Besides doing tai chi, Chinese astronauts also play table tennis or ride a bike and run on a treadmill (踏步机) to help train their breathing.

【推荐1】

It’s a feeling you’ve almost experienced before—the fear of waiting for an exam to start. You worry about whether you’ve prepared well, and about the failure. Gerardo Ramirez and Sian Beilock have found that students do better in exams if they spend 10-minute writing about their anxieties (焦虑).

At first, scientists tested their assumption (假设) in the lab. They asked 20 college students to take two math tests. Before the first test, half of the students sat quietly and the other half wrote about feelings of the coming exam. It turned out that although both groups scored similar marks in the first test, the writing group did much better at the second test. Their scores improved; rising by an extra 5%. And the students who sat quietly actually did worse; their marks were 12% lower.

But did the act of writing itself ________? To answer that, scientists ran another experiment in a real setting. This time, they worked with 100 ninth-grade students and divided them into two groups, the students were asked for a 10-minute writing exercise. Half of them were required to write about their worries about the coming exam, while the other half wrote about an unrelated topic. Only then did they take the exam.

Their final scores showed that if the students wrote about unrelated topics, their scores were lower. If they wrote about their worries, their anxieties had no effect on their marks. And when Ramirez divided the students into two groups according to how anxious they were, only the high group benefited from the exercise.

Ramirez and Beilock’s study has obvious practical (实际的) effect. They’ve found a simple way of helping the anxious students to perform at their true level. They have also shown that the key to control our anxieties is not to push them aside, but to face them.

【推荐2】Chinese researchers reached the top of Qomolangma on May 4, 2022. They set up the world’s highest automatic (自动的) weather station at an altitude (海拔) of 8,830 meters. This helps them to study the influences of climate (气候) change on the environment.

It is the highest automatic weather station in the world now. It has taken the place of the station sitting at an altitude of 8,430 meters on the south side of the mountain, which is the second highest now. This allows Chinese scientists to collect data (数据) directly from the top of the world’s highest mountain for the first time.

Collecting and studying data from Qomolangma is not easy. But the data will give valuable information about the condition of local glaciers (冰川) and mountain snow. It will also help scientists study and understand the global monsoon (季风) system, so experts can make proper decisions about climate change.

Yao Tandong, a famous expert, said Chinese scientists had set up eight weather stations from 5,200 to 8,830 meters above sea level. Half of the stations were set up at an altitude higher than 7,000 meters. “Along with strong government support and hard work of scientists, China has become a global front-runner in fields such as climate change.” Yao said.

The umbrella is very common in our daily life. It keeps the rain and the sun off the people. We can fold up (折叠) most umbrellas.     1    

However, the umbrella is not always as common as it is now.     2     Someone carries an umbrella and walks behind the king or an important person. Some African countries still use them in this way. Umbrellas have a long history. People in different parts of the world begin to use umbrellas at different times.     3     At that time, smart Chinese carried umbrellas to Egypt and India. In Greece and Rome, men wouldn’t use them.     4    

England was probably the first country in Europe where the common people used umbrellas against rain.     5     So umbrellas are very useful.

Everybody uses umbrellas today. The next time when you carry one, thinking that for centuries only great men and women used them, you’ll feel you are important people, too.

【推荐1】Sometimes, you may not finish drinking your glass of water before you go to bed. The next morning, you might want to drink it. But is the water still safe to drink?

If you have clean water in a clean glass, you’re fine to drink it for a day or two. But it may taste strange. That’s because there is carbon dioxide(二氧化碳) in the air. After about 12 hours, carbon dioxide reacts(反应) with the water in your glass. This changes its Ph level a little.

Also, there might be more microorganisms(微生物) in your water if you leave it out overnight. Microorganisms grow more quickly at room temperature(室温). These microorganisms can stay on your glass. They may make you get sick more easily. But if you clean your glasses very often, this will not be a big problem.

【推荐3】

I’m sure you all know how important recycling is. Recycling is that you take old things and turn them into new things. It sounds like magic. But it’s actually very scientific.