Here's a list of some interesting facts about stars; some you might already know, and few that are going to be new.
The sun is the closest star to the earth. The sun is about 150 million kilometers away. Our sun, like most other stars, gives off power and light by nuclear fusion, which happens exactly where it's the hottest. The sun is about 4.5 billion years old and it will still last six billion years or so. When it runs out of its fuel, it would develop into a red star when increasing in size.
Since stars are billions of light years away, it may be hard to recognize that stars are in continuous battles with themselves. All the stars have their own gravitational pull that pulls them. The surprising part is that the nuclear fusion occurring inside the star truly produces an outward push to resist the gravitational force, which keeps its present shape.
Stars have different colors. The hottest stars are surprisingly the smallest ones and are blue in color. Their temperatures go to about 12,000 Kelvin. Although the yellow-colored stars are the middle-sized ones just like the sun, their temperatures fall to about 6,000 Kelvin. And lastly, the coolest and greatest ones are colored red and the temperatures of them are about 3,000 Kelvin.
When looking at the night sky, we may think that stars are up there alone. But don't be surprised that these heavenly bodies in fact come in pairs. And stars can even come in groups of 3 or even 4!
1. What will happen when the sun runs out of its fuel?| A．It will disappear slowly. | B．It will last six billion years. |
| C．It will become a white star. | D．It will become larger in size. |
| A．All stars are in a state of balance. | B．It's hard for the stars to keep their shapes. |
| C．The stars have the same gravitational pull. | D．The stars always stay in peace with one another. |
| A．It is blue when it is very cold. | B．It looks red when it is far away. |
| C．It seems yellow when it is over 3,000 Kelvin. | D．It has something to do with its size and temperature. |
| A．They appear only in pairs. | B．They appear without rules. |
| C．They stay alone here and there. | D．They appear in small groups or in pairs. |
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【推荐1】For almost as long as people have walked on Earth, they have looked up at the moon and wondered: How did the moon get there? How long has it been there? Scientists have studied questions. And now, a group of researchers from California have an answer. Based on their studies, they think the moon is 4.51 billion years old.
For years, researchers have been studying the many rocks American astronauts brought back from the moon between 1969 and 1972. The early rock studies led many scientists to think the moon was formed long ago—about 4.3 billion years ago.
Scientists believe the moon was created when a huge rocky object about the size of Mars truck a very young Earth. Then some of the pieces from that violent crash came together in space to form the moon. But that estimated age, 4.3 billion years, created a problem for scientists. That is because it does not leave much time for life to get started and develop on planet Earth.
Researchers wanted a better, more exact estimate of when the moon was formed. They found their answer by studying a moon rock brought back to Earth in 1971. They looked closely for signs of a matter in the rock called zircon (锆石). And they found out that the moon is actually older. The moon didn’t form 4.3 billion years ago, but it formed at least 4.51billion years ago.
Those extra years solves the problem of life on Earth. And this solution gives scientists a better understanding of how life formed here and how it might form on other planets.
The new information means the moon was orbiting Earth just 60 million years after the birth of our solar system. Then the Earth had much more time to cool down, form the atmosphere, form the water and then finally had all the conditions met for life.
1. How did the moon come into being?| A．By breaking away from Earth. | B．By a solar storm caused by Earth. |
| C．By gathering other small planets in space. | D．By a big crash between a huge object and Earth. |
| A．It is based on a false rock. | B．It led to a wrong idea on the birth of Earth. |
| C．It doesn’t explain the origin of life on Earth. | D．It was misled by the rocks brought from the moon. |
| A．A matter called zircon. | B．The previous conclusion. |
| C．A theory about life on Earth. | D．The understanding of the moon. |
| A．tested exactly. | B．judged roughly | C．argued briefly | D．designed carefully |
【推荐2】Space is becoming more crowded. Quite a few low-Earth-orbit (LEO) satellites have been launched into the sky, which are designed to move around the Earth only a few hundred kilometres above its surface. SpaceX and OneWeb plan to launch LEO satellites in their thousands, not hundreds, to double the total number of satellites in orbit by 2027.
That promises to change things on Earth. LEO satellites can bring Internet connectivity to places where it is still unavailable. This will also be a source of new demand for the space economy. Morgan Stanley, a bank, projects that the space industry will grow from $350 billion in 2016 to more than $1.1 trillion by 2040. New Internet satellites will account for half this increase.
For that to happen, however, three worries must be overcome. Debris (碎片) is the most familiar concern. As long ago as 1978, Donald Kessler, a scientist at NASA, proposed a scenario (设想) in which, when enough satellites were packed into low-Earth orbits, any collision could cause a chain reaction which would eventually destroy all spacecraft in its orbital plane. Solutions exist. One solution is to grab the satellites with problems and pull them down into the Earth’s atmosphere. Another is to monitor space more closely for debris. But technology is only part of the answer. Rules are needed to deal with old satellites safely from low-Earth orbits.
Cyber-security is a second, long-standing worry. Hackers could take control of a satellite and steal intellectual property, redirect data flows or cause a collision. The satellite industry has been slow to respond to such concerns. But as more of the world’s population comes to rely on space for access to the Internet, the need for action intensifies. Measures will surely be taken to protect network security.
The third issue follows from the first two. If a simple mistake or a cyber-attack can cause a chain reaction which wipes out hundreds of billions of dollars of investment, who is responsible for that? Now the plans of firms, wishing to operate large numbers of satellites are being studied. But there is a long way to go before the risks are well understood, let alone priced.
As space becomes more commercialized, mind-bending prospects open up: packages moved across the planet in minutes by rocket rather than by plane, equipment sent to other small planets, passengers launched into orbit and beyond. All that and more may come one day. But such activities would raise the same questions as LEO satellites do. They must be answered before the space economy can truly develop.
1. What can we learn about LEO satellites from the passage?| A．They will limit the space economy |
| B．They will increase in large numbers. |
| C．They will move beyond the Earth as far as possible. |
| D．They will monitor old satellites. |
| A．To avoid network attack. |
| B．To make the Internet accessible to backward areas. |
| C．To lighten the financial burden of space firms. |
| D．To accelerate the development of bank industry. |
| A．block low-Earth orbits with packed satellites |
| B．pull down satellites into Earth’s atmosphere |
| C．put the disposal of old satellites at high risks |
| D．bring destruction to spacecraft in the same orbit |
| A．It should be further confirmed for its ownership. |
| B．It should be continued because of its advantages. |
| C．It should be done carefully to avoid potential risks. |
| D．It should be stopped in the face of the space economy. |
【推荐3】As the Hubble Space Telescope celebrates 25 years in space this week, NASA and its international partners are building an even more powerful tool—the James Webb Space Telescope. This telescope will be 100 times more powerful than Hubble.
“JWST will be able to see back to about 200 million years after the Big Bang,” NASA said on its website. “What the Webb will really be doing is looking at the first galaxies of the universe,” Mark Clampin said. “We will also be able to look in very dark parts of the universe where stars are being born.”
Inside a large clean room where no dust can harm the telescope, a team of engineers dressed in white, work on building the JWST. The space telescope will weigh 6.4 tons. Its main mirror will be 6.5 meters in diameter(直径), three times as large as Hubble’s. JWST will carry four instruments, including cameras and spectrometers(分光仪) that can catch extremely weak signals.
“The Webb will have 70 times the light-gathering capacity of Hubble. So the combination of the large size and the infra-red(红外线的) capacities will allow us to observe this epic of the universe past,” explained Matt Greenhouse.
Even more the telescope should further the search for life elsewhere in the universe by opening a new window on planets outside the solar system—known as exoplanets—that might have water and orbit their stars at a suitable distance to prevent freezing or boiling. “Webb is big enough to have a high probability of finding evidence of life in the atmosphere of exoplanets,” said Greenhouse.
Unlike the Hubble Space Telescope, which circles the Earth, the JWST will go even further, to a place 1.5 million kilometers away in space. That distance will keep the telescope cold, prevent it from being blinded by its own infra – red light and shelter it from radiation. The heavy telescope is scheduled to launch from French Guiana in October 2018. “Just as Hubble rewrote all the textbooks, Webb will rewrite it again,” said Greenhouse.
1. What’s the major purpose of building the James Webb Space Telescope?| A．To replace the 25-year-old Hubble Space Telescope. | B．To find aliens outside the solar system. |
| C．To rewrite all the textbooks. | D．To look at the first galaxies of the universe. |
| A．Hubble can see back to about 200 million years after the Big Bang. |
| B．JWST is 100 times more powerful than Hubble. |
| C．JWST will be sent out of the solar system. |
| D．JWST is 70 times heavier than Hubble. |
| A．About 2 meters. | B．About 3 meters. | C．About 1 meter. | D．About 6 meters. |
| A．Planets outside the solar system. | B．Planets outside the earth-moon system. |
| C．Planets without water or atmosphere. | D．Planets in the first galaxies. |
【推荐1】Different people enjoy different amounts (数量) of human contact. While some adore making lots of friends, others prefer plenty of time on their own. However, is there such a thing as too much time alone? And how does isolation (孤独) affect humans?
In April, a Spanish athlete named Beatriz Flamini came out of a cave where she had spent 500 days as part of a study on social isolation. During her time 70 metres underground, Flamini had no human contact at all. However, she did record videos of herself and was monitored continually by scientists.
Doctors measuring the effects of isolation are building up a picture of how it can change the way people experience the passing of time, and how it affects the body’s natural clock. Flamini first entered the cave on 20 November 2021, but she lost track of time 65 days later. During her time underground, she sometimes experienced auditory hallucinations, which means that she was hearing noises that weren’t there. The isolation affected her balance when she came out of the cave, and she also had to get used to being in sunlight.
Isolation studies are important for planning for long-lasting space tasks. Although astronauts (宇航员) often work with other members, the teams are small and their living quarters are small, too. For example, the astronaut Kjell Lindgren spent 141 days on board the International Space Station with never more than five teammates for company. This summer, four volunteers will start a year of living inside a big box, as part of NASA’s Crew Health and Performance Exploration Analog. The aim of this experiment is to find out how astronauts will manage extreme isolation and stay healthy while living on Mars.
1. What does the underlined word “adore” in Paragraph 1 mean?| A．Avoid. | B．Allow. | C．Love. | D．Stop. |
| A．She watched videos every day. | B．She stayed alone for over a year. |
| C．She explored the cave’s secrets. | D．She talked with scientists sometimes. |
| A．Disorder of body clock. | B．Poor eyesight. |
| C．Complete loss of balance. | D．Sudden deafness. |
| A．Extreme Isolation | B．Power of Human Contact |
| C．Underground Experiences | D．Astronauts’ Health Experiments |
【推荐2】Dogs may appear to have selective hearing when it comes to orders but research suggests they are paying attention to human chitchat.
Researchers, who arranged for headphone-wearing dogs to listen to excerpts (节录) from the novel The Little Prince, revealed their brains can tell the differences between speech and non-speech when listening to human voices, and show different responses to speech in an unfamiliar language.
The research involved 18 dogs of various ages and breeds (品种) that were trained to lie in an MRI scanner with headphones on. They were then played recordings either of humans reading excerpts from The Little Prince or those same recordings cut up into small pieces and put back together in a different order so it sounded unnatural.
The results, published in the journal Neuro Image, revealed the dogs’ brains showed a different activity pattern in the primary auditory cortex (听觉皮层) for speech compared with non-speech, with the findings similar regardless of whether the language used—Hungarian or Spanish—was familiar. Curiously, the longer the dogs’ heads were, the better their brains could distinguish speech from non-speech.
The team also found the activity pattern was stronger for non-speech. In humans, we typically see stronger response to speech.
The research also revealed familiar and unfamiliar languages gave rise to different responses in the secondary auditory cortex—but only for speech. That was important, said Andics, senior author of the study at Loránd University in Hungary, as it suggested the ability to distinguish between languages was not simply down to the speakers being different.
Instead, the team said, the differences seen between languages for speech are probably down to exposure to the familiar language and a sensitivity to language-specific regularities.
“This is also supported by the observation that older dogs show the stronger discrimination between the two languages,” said Andics.
1. What’s the function of Paragraph 1?| A．To make a comparison. | B．To introduce the subject. |
| C．To provide the background. | D．To propose a definition. |
| A．The process of the research. | B．The purpose of the research. |
| C．The subject of the research. | D．The outcome of the research. |
| A．How old and what breeds the dogs are. |
| B．How many times the dogs read the book. |
| C．How dogs’ brains react to different speeches. |
| D．How dogs get familiar with the languages used. |
| A．They have met more different speakers. |
| B．They have been exposed to stricter training. |
| C．They possess a better sense of commitment. |
| D．They share the speakers’ environment longer. |
【推荐3】This may sound like a joke about a lazy person’s dream job. Earn big money by staying in bed and watching TV. But this is really happening, and it’s a project of NASA and two European space agencies the Institute of Aerospace Medicine at the Cologne-based German Aerospace Center and the European Space Agency. I’s called Artificial Gravity Bed Rest Study, aimed at studying how the body adapts to weightlessness in space.
Scientists are seeking 12 women to spend two full months in bed in the fall at a German lab,plus an additional month there for preparation and recovery, The first 12 test subjects, all men, already have started the study.
Participants spend two entire months in bed and remain lying down even to do everyday things like eating, drinking and exercising. They also answer nature’s call and shower, but it’s unclear from the NASA website how those tasks are accomplished in bed.
“Daily routine showering, getting dressed, eating, exercising takes much time when you cannot stand up to do them,” says the website, adding that there is “continuous data collection”, including blood pressure, heart rate, nutrient absorption and also the participants’ feelings. Study subjects will spend the 60 days with their heads tiled down six degrees, which imitates conditions in space.
Participants are encouraged to pass the time by watching TV, taking online courses, reading and any other activities they can perform while lying down alone in bed to relieve what could be boredom. Family and friends are allowed to visit.
The high $ 18,500 payment for two months of lazing about is probably a major motivation for people willing to go through something this extreme. However, if you’re an American who really needs the money, you probably can’t afford it. Candidates need to travel to Cologne four times at their own expense for the employment process between April and July. Plus, they need strong German-speaking skills Also participants need to be nonsmokers between ages 24 and 55, in good health, with normal body weight.
1. What are participants expected to do during the study?| A．Report their feelings regularly. | B．Complete their daily routines in bed. |
| C．Keep their bodies tilted down six degrees. | D．Record their physical responses every day. |
| A．The changes in their weight. | B．Their behaviors to weightlessness. |
| C．The ways they do their daily things | D．Their physical and mental reactions |
| A．The language skills they need. | B．The difficulty meeting family. |
| C．The possibility that they feel dull. | D．The slow discovery of their health. |
| A．challenging for Americans | B．tailored to thin persons |
| C．easy for the youth to satisfy | D．suitable for most people |
【推荐1】Restaurants, farmers and food businesses are turning to chemistry and physics to deal with the problem of food waste. Some companies are testing coverings to slow the fruits’ ripening(成熟) process and packets to keep food fresh. Others are developing digital sensors that can tell when meat is safe to eat.
Experts say growing awareness of the costs of food waste has led to more efforts to deal with the problem. ReFED is a group that studies food waste. It estimates 225,000 kilograms of food can be kept out of waste areas each year with special high-tech coverings.
But the cost can be a barrier for some companies and shoppers. Kroger, the largest food-store company in the US, ended its deal with Apeel Sciences in 2022. The deal ended because Kroger said shoppers were not willing to pay more for fruits with Apeel’s special covering to keep them fresh.
Many companies are working on ways to help reduce food waste. A Sweden-based company is trying developing a sensor that can show if meat is safe to eat by measuring the buildup of bacteria inside its container. And Ryp Labs, based in the US and Belgium, is working on a sticker for fruits and vegetables that would release(释放) gas to slow ripening.
Some companies find it better to use proven technology in new ways. For example, Chicago-based Hazel Technologies has been trying selling a chemical compound(化合物), called 1-MCP, which is used in a room to slow the fruits’ ripening process. The company now sells packets that can slowly release 1-MCP into small containers of fruits.
“The science is promising, but it is only part of the solution,’” said Yvette Cabrera. She is the director of food waste for the Natural Resources Defense Council. “Most food waste happens at home. Reducing food sizes, buying smaller quantities or improving the accuracy of freshness date could have even more effects than new technology. Overall as a society, we don’t value food as it should be valued,” Cabrera said.
1. How does the author start paragraph 1?| A．By showing experiments. | B．By quoting experts’ words. |
| C．By listing data. | D．By giving examples. |
| A．They were not convenient to use. |
| B．Food stores found them ineffective. |
| C．Customers disliked paying extra money. |
| D．They might cause pollution to the fruits. |
| A．Building storage rooms. | B．Using chemical methods. |
| C．Making packets. | D．Developing a sensor. |
| A．Ways of reducing food waste. |
| B．Benefits of saving food at home. |
| C．Kinds of fresh food in the market. |
| D．Funds of dealing with food waste. |
【推荐2】It was a red-letter day in the history of medicine-“Target Zero Day”, May 8th, 1980, marking the complete removal of smallpox, a terrifying disease. It was untreatable but, luckily, it turned out that vaccination (接种疫苗) provided good protection- -and that mass immunization (免疫) could wipe out the small- pox virus by blocking its spread.
According to legend, vaccination was invented by Dr Edward Jenner. Jenner showed that healthy children vaccinated with cowpox, a mild infection of cattle, could not catch smallpox. He was supposedly inspired by a comment from a local milkmaid, but there is evidence that the idea came from a medical friend, John Fester, who had experimented with cowpox. Nevertheless, Jenner deserves credit for introducing vaccination into the medical mainstream with his paper published in 1798.
In 1966, 160 years after the prediction that vaccination would clean off the disease, the World Health Organization launched its Smallpox Eradication Programme. This heroic 1-year drive was directed by two American public health doctors, DA Henderson and Bill Forge. Their hardships were enormous: One WHO official even promised to eat a tyre if smallpox was removed; Henderson promised to send him the tyre and wished him good appetite. But Henderson and Foege's hard work paid off--three years after the last smallpox case was informed (to make sure no outbreaks had been missed) Target Zero Day was declared.
40 years on, should we remember Target Zero Day? First, to celebrate victory of preventative medicine and freedom from a cruel disease. Then, we must remember the victims of smallpox. It had previously killed 1 in 12 worldwide. In 1914, a Canadian professor warned against forgetting smallpox, which was fast disappearing from North America. It went on to kill at least another 250 million people -- three times more than both world wars combined. Target Zero Day also reminds us of undefeated infections, including polio, measles, malaria, and of course the coronavirus Covid-19. Let's recognize Target Zero Day for what it is: a milestone in world history and a monument to the art of the possible.
1. What inspired Jenner to invent the vaccination?| A．A medical friend. | B．A local milkmaid. |
| C．Cattle. | D．Children. |
| A．To introduce the support from the WHO. |
| B．To stress the importance of good appetite. |
| C．To suggest the difficulty in removing smallpox. |
| D．To show his determination to carry on the drive. |
| A．In paragraph 1. | B．In paragraph 2. |
| C．In paragraph 3. | D．In paragraph 4. |
| A．A promise made is a debt unpaid. | B．A trouble shared is a trouble halved. |
| C．Something is better than nothing. | D．Nothing is impossible to a willing heart. |
【推荐3】Friends play an important part in our lives, and although we may take friendship for granted (take…for granted认为……理所当然), we often don’t clearly understand how to make friends. While we get on well with a number of people, we are usually friends with only a very few of them. For example, the average among students is about 6 per person. In all the cases of friendly relationships, two people like one another and enjoy being together, but beyond that, the degree of intimacy (亲密) between them and the reasons for their shared interests vary (变化) greatly. As we get to know people, we take into account (think about) things like age, race, economic condition, social position, and intelligence. Although these factors (因素) are not of great importance, it is more difficult to get on with people when there is a marked (great) difference in age and background.
Some friendly relationships can be kept on argument and discussion, but it is usual for close friends to have similar ideas and beliefs, the same opinions and interests. They often talk about “being on the same wavelength”. It generally takes time to reach this point. And the more intimately involved people become, the more they depend on one another. People who want to be friends have to learn to put up with (stand; bear) annoying (bad) habits and to stand (accept) differences.
In contrast (比较) with marriage, there are no friendship ceremonies (纪念日) to strengthen the association (friendship) between two people. But the supporting and understanding of each other that results from shared experiences and emotions does seem to create (make) a powerful bond (prize; reward), which can overcome differences in background, and break down barriers (障碍) of age, class or race.
1. According to the passage, ______.| A．friends are those who must share their interests |
| B．friends are closer than people who just get on with each other |
| C．all the people know how to make friends |
| D．every student has six friends |
| A．friendship can overcome all differences between two people |
| B．there are no special ceremonies to strengthen friendship |
| C．standing differences in opinion can lead to friendship |
| D．friendship can be strengthened by smiles and soft voices |
| A．watch the same TV programs |
| B．are the same in all ways |
| C．have the same background |
| D．share the same way of thinking and the same interests |
| A．Even friends may have different opinions. |
| B．Friends never argue with each other. |
| C．It generally takes time for people to become close friends. |
| D．Someone’s habits may annoy (upset) his friends. |
