The full moon climbs over the eastern horizon (地平线) and hangs like a huge orange globe in the sky. A few hours later, the moon is overhead but seems to have changed. The huge orange globe has become a small silver disk. What has happened? Why has the orange color disappeared? Why does the moon seem so much smaller and farther away now that it is overhead?
The moon appears orange on the horizon because we view it through the dust of the atmosphere. The overhead moon does not really shrink (缩小) as it moves away from the horizon. Our eyes inform us that the overhead moon is farther away. But in this position the moon is actually closer to our eyes than when it is near the horizon.
The change in size is a trick our eyes and minds play on us. When the moon is low in the sky, we can compare its size with familiar objects. It is easy to see that the moon is much larger than trees or buildings, for example. When the moon is high in the sky, however, it is hard to compare it with objects on earth. Compared to the vastness of the sky, the moon seems small.
There is another reason why the moon seems to shrink. We are used to staring at objects straight ahead of us. When an object is difficult to see, our eyes have to try to focus on it. When we move our heads back to look up, we will try hard again. Looking at something from an unaccustomed position can fool you into believing an object is smaller or farther away than it is. However, scientists do not yet understand completely why the moon seems to shrink as it rises in the sky.
1. What makes us puzzled when the moon is high in the sky?| A．It becomes large. |
| B．It looks different. |
| C．Its color disappears. |
| D．Its shape changes. |
| A．It comes nearer. |
| B．It turns orange. |
| C．It goes farther. |
| D．It gets through dust. |
| A．They can affect our judgment. |
| B．They are low on earth. |
| C．They can attract our attention. |
| D．They are large objects. |
| A．The size of the moon often changes. |
| B．The moon is in fact a huge orange globe. |
| C．The moon is beginning to shrink much. |
| D．We do not see the moon as it really is. |
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【推荐1】Since I was born and brought up in a rural town, I have a great interest in nature. Having the chance of studying abroad in my second year at college, I decided to go to Canada just because I wanted to see the beautiful phenomena there. So after I finished the study, I went to Yellowknife in the Northwest. I clearly remember the sixth night in Yellowknife. Suddenly my host mother came to my room around 8 p. m. and told me to change clothes and go outside quickly carrying her camera.
The northern lights were flickering (闪烁) in the sky! I was amazed and just stood there with my mouth open. I forgot to take pictures of the mysterious lights.
Since that night, whenever it was sunny, I went outside at night and looked at the sky. It was so cold that my hands and feet were numb (失去知觉的) with cold. Actually, the time of my being able to be out was limited. I had to bring her camera back to the house in one hour at most, for the camera was going to be broken because of the cold temperature.
As I took pictures of the northern lights, I came to find a characteristic movement of the lights. They first appear in the north part of the sky and then they come down to the south. After that, suddenly, they come in the middle of the north and south only for a while, which is the time when the best northern lights can be seen. Since it is only a few seconds for the northern lights to come down to the middle of the sky, it is very hard to get good pictures.
The stronger the sun acts, the better and stronger northern lights flicker in the sky. That’s because they occur from the collision (碰撞) between atmospheric gases and solar wind. Much more solar wind comes to the earth when the sun is active, leading to the best northern lights.
1. Why did the author forget to take pictures?| A．His host mother didn’t remind him. |
| B．He was shocked by the wonderful sights. |
| C．He lost all the feelings in his hands and feet. |
| D．The lights flickering disappeared after a while. |
| A．The northern lights came out every night. |
| B．The author took lots of pictures with his camera. |
| C．The author could stay as long as he liked outdoors. |
| D．Camera s will be damaged if exposed too long to coldness. |
| A．They are between the north and south. |
| B．They rise in the east and set in the west. |
| C．They appear in the north part of the sky. |
| D．They come down to the south part of the sky. |
| A．The lights of the sun affect the northern lights. |
| B．The lights are caused by the collisions of gases. |
| C．The lights stay in the middle for a very short time. |
| D．The colours of the lights are determined by the height. |
【推荐2】NASA aims to send a man and a woman to the moon by 2024. This is the goal of its Artemis program. But for Artemis to succeed, the U. S. space agency first needs to solve a big problem: the damaging threat of moon dust.
Over billions of years, celestial （天体的）bodies, such as asteroids and meteors, have slammed into the moon. These hits have crushed some lunar rocks into dust. The surfs radiation gives the dust an electric charge that makes it stick to everything. Those powdery bits are like u broken pieces of glass" , notes Mihaly Horanyi, a physicist at the University of Colorado Boulder. The dust is so rough, in fact, that it can damage equipment. If taken in, it might even harm an astronaut's health. Horanyi is part of a team that has now figured out how to overcome one troubling aspect of the dust: its static cling, using a low-powered electron beam （电子束）.When shined onto the dust, that beam sends the dust flying.
During the 1970s, the astronauts in NASA's Apollo missions relied on a very low-tech system to clean lunar dust off their spacesuits. They swept it away with what looked like the brushes used to paint a house. But the electrically charged nature of space dust tended to fail such hand sweepers.
The new electron-beam broom takes advantage of the dust's electrical characteristic. As the beam hits the dust, it releases electrons into the tiny spaces between particles. Some of these negatively charged electrons will be absorbed by the surrounding dust.
One problem with the electron beam, at least for now, is that it leaves up to one-fourth of the dust behind. The Boulder group aims to strengthen that cleaning power. Horanyi says the electron beam is just one of several ways future space explorers could keep surfaces clean. Others might include changes to a spacesuit's design.
1. Why should the moon dust problem be solved?| A．It might affect astronauts' health and equipment. |
| B．It can give off harmful radiation. |
| C．It can stick to the surface of the spaceship. |
| D．It might cause serious crashes. |
| A．The discovery of the electron beam. | B．The way the electron beam works. |
| C．The occurrence of the electron beam. | D．The development of the electron beam. |
| A．It is a low-tech dust cleaning system. |
| B．It leaves three-fourths of the dust uncleaned. |
| C．It needs improvement in the cleaning power. |
| D．It is proved less efficient than other methods. |
| A．Astronauts' health. | B．New spacesuit's designs. |
| C．Spaceship surface features. | D．Future space exploration. |
【推荐3】When Did the First Stars Shine
Our universe is home to countless galaxies(银河), with each galaxy hosting hundreds of billions of stars. Each one is a ball of energies powered by the nuclear explosion of elements in their hearts.
Billions of years ago, there was a time before stars or before lights, called the Dark Ages. There used to be not enough material of high densities(密度)to cause nuclear explosion. Without nuclear explosion, there were no stars.
Those first stars burned fiercely and died quickly. None of them survived to the present day.
Recently, a team of astronomers used 70 hours of observing time to take pictures of six extremely distant galaxies.
Hopefully, upcoming missions, like NASA's James Webb Space Telescope, will be able to directly observe those galaxies in greater detail. And some star mysteries will be disclosed,
| A．Nevertheless, they left their mark. |
| B．Accordingly, there was no visible light either. |
| C．Each one also poured out light into the empty universe. |
| D．It was much darker than it is today with only a little light. |
| E．For example, when did the Cosmic Dawn exactly take place? |
| F．Based on their observations, they were able to estimate the age of the galaxies. |
| G．They're so far away that we can't capture them even with powerful telescopes. |
【推荐1】Many college students turn to ADHD（注意缺陷障碍）medicine during the exam week, which is regarded as “smart drugs” that will help their academic（学术的）performance. The thinking is that if the drugs help students with ADHD improve their focus, they should provide the same benefit for people who don’t have the disorder.
But a new study shows that drugs can actually damage brain function of healthy students who take the drug hoping to boost their intelligence. “It’s not a smart drug which will suddenly improve their ability to understand information they read,” said Lisa Weyandt, a professor at the University of Rhode Island.
To test whether this effect is real or not, researchers organized 13 students to take part in two five-hour study sessions（一段时间）in the lab. The students took the standard 30mg ADHD drugs before one session, and a sugar pill before the other. Students on ADHD drugs did experience an increase in their blood pressure and heart rates. “The medicine was having an effect on their brain,” Weyandt said. The students also showed an improvement in their ability to focus, the researchers found.
However, students on ADHD drugs experienced no improvement in reading comprehension, reading fluency or knowledge reviews, compared to when they’d taken a sugar pill. “We read aloud stories to them and asked them to recall information from the stories, ”she said. “That didn’t improve.”
Worse, the ADHD drug actually harms students’ memory. It’s often misused because people pull all-nighters and they’re tired, and they think it’s going to keep them awake. Maybe it does, but it’s certainly not going to help their academic work. The brain is still developing until the mid to late 20s. It’s important to keep it healthy. There’s also a chance that ADHD drugs could endanger a student’s heart health.
1. Why do some college students take ADHD drugs?| A．To improve their sleeping. | B．To get higher marks. |
| C．To make them feel relaxed. | D．To treat brain disorder. |
| A．Analyze. | B．Affect. |
| C．Improve. | D．Understand. |
| A．They became more focused. |
| B．Their blood pressure was reduced. |
| C．Their reading fluency was greatly raised. |
| D．They could remember better and more quickly. |
| A．In a drug instruction. | B．In a biology textbook. |
| C．In a travel magazine. | D．In a news report. |
It is a fact that givers are happier people than non-givers. According to the Social Capital Community Benchmark Survey, a survey of 30,000 American households, people who give money to charity are 43% more likely than non-givers to say they are “very happy” about their lives. Similarly, volunteers are 42% more likely to be very happy then non-volunteers.
The happiness difference between givers and non-givers is not due to differences in their personal characteristics, such as income or religion. Imagine two people who are identical in terms of income and faith, as well as age, education, politics, sex, and family circumstances, but one donates money and volunteers, while the other does not. The giver will be, on average, over 40 percentage points more likely to be very happy than the non-givers.
A number of studies have researched exactly why charity leads to happiness. The surprising conclusion is that giving affects our brain chemistry. For example, people who give often report feelings of euphoria, which psychologists have referred to as the “Helper’s High”. They believe that charitable activity produces a very mild version of the sensations people get from drugs like morphine and heroin.
Of course, not only does giving increase our happiness, but also our happiness increases the possibility that we will give. Everyone prefers to give more when they are happy. Researchers have investigated this by conducting experiments in which people are asked about their happiness before and after they participate in a charitable activity, such as volunteering to help children or serving meals to the poor. The result is clear that giving has a strong, positive causal impact on our happiness, so does happiness on giving
1. According to Paragraph 2. We can learn that .
| A．only those people who gave money to charity will be happy |
| B．more givers say they feel having happy lives than non-givers |
| C．those who donate money are happier than those who volunteer |
| D．42% of the volunteers say they are as happy as the non-volunteers |
| A．Income. | B．Faith. | C．Education. | D．Donation. |
| A．relaxation | B．uncertainty |
| C．nervousness | D．pleasure |
| A．ask for more donations | B．stop charitable activity |
| C．be likely to give more | D．cook food for the poor |
| A．Giving brings happiness. | B．Americans love donating. |
| C．The happiness difference. | D．Feelings of volunteers. |
【推荐3】Naturalist John Muir called the Marin County woods named for him “the best tree-lover's monument that could possibly be found in all the forests of the world.”
Located only 11 miles north of the Golden Gate Bridge near San Francisco, California, USA. Muir Woods puts some of nature's most huge creations within reach of little feet, hands, and imaginations.
“Muir Woods is home to a small forest of redwood trees that reach to the sky,” says David Shaw of the Golden Gate National Parks Conservancy. “Redwoods grow taller than any other tree species in the world. The average age of the redwoods here ranges from 400 to 800 years old and many ancient specimens have been around for more than a thousand years.”
William Kent, the man who donated the 295 acres to create the Muir monument, grew up in Marin and played in similar redwood forests. That childhood experience inspired him to save the redwoods as an adult.
“Young people can learn about young William Kent when they visit here，” says ranger(护林员) Timothy Jordan. “Kent’s early connection with nature developed his love of the outdoors. As an adult, he witnessed the destruction of many Bay Area redwood forests. This, with the writings of John Muir, inspired Kent's conservationism.”
Walking (and playing)in, on, and around the redwoods will help kids understand why young Kent was so fascinated(深深吸引) by the trees. Ranger Jordan encourages children to lie down and look up at the treetops, hug a redwood tree, and start a nature journal like John Muir.
“Have kids find a redwood spray(小树枝)the same age as them, count the rings in trees, and sit inside of a hollow redwood tree on Fern Creek.” he advises.
After all the interaction, the kids just may be ready to rest. Take this time to “be quiet and listen to the sounds of the forest,” says Shaw. "Encourage kids to think about how these trees have stood quietly through year after year of rain, sun, and sometimes even snow.”
1. What do we know about Muir Woods from Shaw's words?| A．It is America s largest redwood forest. |
| B．It has redwoods of a very great age. |
| C．It receives child visitors only. |
| D．It is home to many rare trees. |
| A．He had an unusual adult life. |
| B．The Golden Gate Bridge was constructed. |
| C．He was inspired by the works of John Muir. |
| D．The redwood forests attracted a lot of young people. |
| A．Experience Muir Woods silently. |
| B．Look for special redwood sprays. |
| C．Sit inside of a hollow redwood tree. |
| D．Write a nature journal like John Muir. |
| A．To remember a famous naturalist. |
| B．To discuss the protection of forests. |
| C．To share knowledge about redwoods. |
| D．To introduce a famous redwood forest. |
