Scientists have observed a planet being swallowed by its host star for the first time. They believe this could be a preview of what could one day happen to Earth — but don’t worry, that won’t be for about another five billion years.
The US astronomers said that when the sun finally does swallow Earth, it will cause only a “tiny change” compared to the cosmic (宇宙的) explosion they just witnessed. Most planets are believed to meet their end when their host star runs out of energy, turning into a red giant that massively expands, destroying anything unlucky enough to be in its path.
Astronomers had previously seen the before-and-after effects of this process, but had never caught a planet in the act of being consumed. Lead researcher Kishalay De said the accidental discovery unfolded like a “detective story”.
“It all started about three years ago when I was looking at data from the Zwicky Transient Facility survey, which took images of the sky every night,” Dr. De said.
He came across a star that had suddenly increased in brightness by more than 100 times over a 10-day period. The star is in the Milky Way galaxy (银河系), around 12,000 light years from Earth near the Aquila constellation (天鹰座). Dr. De had been searching for binary star (双星) systems, in which the larger star takes bites out of its companion, creating incredibly bright explosions called outbursts. But data showed that this outburst was surrounded by cold gas, suggesting it was not a binary star system.
And NASA’s infra-red space telescope NEOWISE showed that dust had started to shoot out of the area months before the outburst. More puzzling still was that the outburst produced around 1,000 times less energy than previously observed mergers (合并) between stars.
1. What is paragraph 2 mainly about?| A．US astronomers are concerned about the future of Earth. |
| B．The harm the cosmic explosion may bring. |
| C．A prediction made by US astronomers about Earth. |
| D．Harmony between the Earth and the Sun is of great importance. |
| A．He loves detective stories. | B．His efforts paid off at last. |
| C．The survey made him suffer. | D．He took pride in his discovery. |
| A．It is near the Aquila constellation. | B．It has the strongest brightness. |
| C．It can swallow other host stars. | D．It causes explosions constantly. |
| A．Science. | B．Literature. | C．Documentary. | D．Education. |
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【推荐1】Walking around the world may seem impossible, but that didn't stop one American woman from putting one foot in front of the other.
In 2014, Angela Maxwell, then in her early 30s, began her walk around the world alone. After six-and-a-half years and over 32,000 kilometers, Maxwell's walk ended where it began.
Before she left on her journey, Maxwell's found inspiration from women explorers of the past. “I read their books in hopes of finding encouragement—and I did—by learning about their challenges and struggles as well as their triumphs. Each woman's story was vastly different and it gave me the confidence to give my walk a try.” Maxwell told the BBC.
After selling all of her belongings, Maxwell left her hometown of Bend, Oregon, with 50 kilograms of camping gear, dehydrated（脱水的）food, a water filter and clothing for all seasons.
Maxwell's worldwide walk wasn't easy. She suffered from sunburn and heatstroke in the Australian desert and dengue fever in Vietnam. She heard gunshots while camping in Turkey and was attacked in her tent in Mongolia. Still, she continued to walk. She learned beekeeping in the Republic of Georgia and camel-handling on the historical Silk Road in Mongolia. She helped a farmer renovate his house in Sardinia and handed out food to homeless people in Italy. She gathered countless stories that she'd go on to speak about at schools, universities and conferences.
When the BBC asked her what kind of person it takes to walk around the world, Maxwell said. "It's probably a combination of ambition, a little stubbornness and a pinch of passion—not for hiking as a sport, but for self-discovery and adventure."
"I didn't start walking because I was fearless—but rather because I was terrified. I was more afraid of not following my heart than I was of losing everything I owned and loved."
1. Where did Maxwell return after finishing her walking?| A．Bend Oregon. | B．Mongolia. |
| C．Australia. | D．The Republic of Georgia. |
| A．The beautiful scenery around the world. |
| B．The sufferings women explorers experienced. |
| C．The encouragement from women explorers. |
| D．The stories of those past women explorers. |
| A．Fearless and brave. | B．Caring and strong-willed. |
| C．Passionate and careful. | D．Cautious and ambitious. |
| A．She was so curious as to explore the world. |
| B．She was not frightened of anything unknown. |
| C．She was afraid of not following her heart. |
| D．She was afraid of losing what she owned and loved. |
【推荐2】A conductor, Alondra de la Parra, in Mexico hopes to gain listeners through a new work in which a clown (小丑) performs with musicians. The new performance, “The Silence of Sound”, puts musicians on stage rather than below the stage in an area known as the pit (乐池).
Through classical music, the orchestra (管弦乐队) plays an important part in the story as the clown searches for meaning and happiness from the music.
“The stories we tell in this show are just some out of the many possible stories one can come up with when listening to classical music,” Alondra de la Parra said. Formal music of Western culture is often described as “classical”. She added, “We hope to reach a larger audience so that they fall in love with the orchestra, and also to give some dreams, imagination and art in this difficult period of time that we are living in.”
Mexican clown performer Gabriela Muioz performs with the musicians. She does not speak during the performance. Instead, she acts with images, such as birds in flight. “My character is one I've played for many years already,” Muioz said. A character is a person that appears in a story, play, or book. She added that the clown goes on a trip, or journey, to “find her inner music that allows her to dance to her own rhythm (节奏).”
Alondra de la Para chose music including pieces written by Claude Debussy, Sergei Prokofiev and Igor Stravinsky among others. She said she wanted to have different kinds of works, “one after the other, that could be a very beautiful sample as an introduction to the orchestra of pieces that anybody can fall in love with immediately.”
The two women have been working together on the project for six years, recently facing issues created by the pandemic.
1. What does Alondra de la Parra think of the stories performed in the show?| A．They take place every day. | B．They are famous modern ones. |
| C．They seem familiar to the audience. | D．They help better understand the music. |
| A．To encourage people to realize their dreams. | B．To comfort people living alone. |
| C．To offer chances to less-famous persons. | D．To enlarge the influence of the orchestra. |
| A．Various. | B．Peaceful. | C．Simple. | D．Merry. |
| A．Every Piece of Music Tells a Lovely Story | B．Music Show Combines Sound and Silence |
| C．Musicians Play Music Without Sound | D．Musicians Tell Stories on the Stage |
【推荐3】At first sight, Sky Brown may appear to be like any other 11-year old crazy about skateboarding. However, spend a few minutes observing the young girl skating and you will realize that she is not an ordinary skater, but a prodigy. In addition to winning the gold at the United Kingdom National Skateboarding Championship in 2019, she is currently ranked third in the world.
These achievements, along with a bronze medal at the September 2019 Park World Skateboarding Championship held in Sao Paulo, Braxil, have all but guaranteed the young girl a spot in the four-person women's team representing the UK in the skateboarding competitions at the 2020 Summer Olympics in Tokyo. If Brown, who will turn 12 shortly before the Tokyo Games, participates in the upcoming Olympics qualifying events and remains injury-free, she will become the youngest British Olympian at the Summer Games. The previous record was held by swimmer Margery Hinton, who was 13 years and 43 days old when she competed at the 1928 Olympics in Amsterdam, Netherlands.
When asked if she was nervous about her first Olympics, the girl said, “I don’t fell nervous. It will be really cool to be the youngest Olympian. People might think you're too young or that you can't do it, but I want to show that it's not about your size or age. I want to be in the Olympics to inspire other girls and show them you can do anything, I'm excited about Tokyo. I love Simone Biles' attitude. She just goes for it. It seems nothing can stop her.”
The young girl desires to be a skateboarder, surfer and dancer, and even play the guitar when she grows up. However, for now, she is focusing on perfecting a new move — a backside 540, which involves spinning one and a half times towards the toes — for the Olympics. We have a feeling this young girl will be on the Olympic stage for many years to come!
1. What does the underlined word “prodigy” in Paragraph 1 probably mean?| A．Guide. | B．Success. | C．Amateur. | D．Talent. |
| A．Margery Hinton will join in it. |
| B．It will be Sky Brown's first Olympics. |
| C．It will be a chance for Sky Brown to break a skating record. |
| D．Margery Hinton will fall behind due to injury. |
| A．ability | B．nervousness | C．attitude | D．motivation |
| A．She has a bright future. |
| B．She still has a lot to learn. |
| C．She should focus on just one thing. |
| D．She has sacrificed a lot for skateboarding. |
【推荐1】When it comes to cooling the planet, forests have more than one trick upon their trees. A new study finds tropical (热带的) forests help cool the average global temperature by more than 1℃. “The effect is largely from forests’ ability to stockpile CO2. But around one third of that tropical cooling effect comes from several other processes, such as the letting-out of water vapor (水蒸气),” researchers reported on March 24 in Frontiers in Forests and Global Change.
“We tend to focus on CO2 and other greenhouse gases, but forests can not only keep CO2,” said Deborah Lawrence, an environmental scientist at the University of Virginia. “It’s time to think about what else forests are doing for us besides keeping CO2.”
“Researchers already know that forests influence their local climates through various chemical processes. Trees let out water vapor through their leaves and, like human sweating, this cools the trees and the things around them. But on a global scale, it isn’t clear how the other cooling works compared with the cooling provided by forests’ ability of keeping CO2,” Lawrence said.
So she and her colleagues studied how over-cutting would affect global temperatures, using data gathered from other studies. For example, the researchers used data to decide how much the letting-out of CO2 stored by those forests would warm the global temperature. They then compared those results with other studies’ results of how much the loss of other aspects of forests.
The researchers found that in forests at latitudes (纬度) from around 50°S of the equator to 50°N, the primary way that forests influenced the global average temperature was through CO2 store. But other cooling factors still played large roles.
1. What does the underlined word “stockpile” in paragraph 1 mean?| A．Improve. | B．Explore. | C．Store. | D．Defend. |
| A．Forests need CO2 to keep their balance. | B．Some chemicals are harmful to forests. |
| C．Forests can sweat and breathe like humans. | D．Forests may benefit us in many other ways. |
| A．The result of Lawrence’s research. |
| B．Lawrence’s research method. |
| C．The difficulty that Lawrence was faced with. |
| D．The reason why Lawrence studied trees. |
| A．Nature. | B．Technology. | C．Culture. | D．Sports. |
【推荐2】How did life come about on Earth? Did it appear in a flash of light? Well, not exactly. A study published in the journal Nature Communications in March shows that lightning may have played a significant role in the creation of life on Earth.
When lightning hits sand, soil or stone, it melts the materials into a glassy material called fulgurite (闪电熔岩). When a group of researchers examined a particular fulgurite, they found a thick, tree-root-like structure extending down about a foot and a half (about 0.46 meters). “(It was) just entirely made of glass and (had), like, burned soil on the outside of it,” said Benjamin Hess, study author and graduate student at Yale University, US.
But what Hess and his colleagues at the University of Leeds, UK, found inside the fulgurite was even more impressive. According to Science News, “By firing X-rays and electrons (电子) at the fulgurite, and observing how those beams (光线) interacted with the material, the researchers were able to detect its composition.”
They discovered that the fulgurite contained schreibersite (磷铁石), a phosphorus (磷) mineral that can be dissolved in water. Phosphorus is essential for the formation of DNA and cell membranes (薄膜), as well as the formation of teeth and bones in humans, according to the website Phys.org.
It has long been thought that meteorites (陨石) were responsible for delivering this element to Earth. However, life began between 3.5 to 4.5 billion years ago when fewer meteorites were impacting Earth, reported CNN.
According to MSN, Hess and his colleagues estimated that early Earth saw one to five billion lightning flashes every year. Of those, anywhere from 100 million to 1 billion would have struck the ground annually, accounting for between 110 to 11,000 kg of phosphorus per year. While this is a large range, “even the low end is enough to potentially fuel the first life forms, and a quantity that may have eventually exceeded meteor strikes”, MSN reported.
1. What does the underlined word “significant” in paragraph 1 mean?| A．important | B．impressive |
| C．attractive | D．interesting |
| A．It looks like a tree root. |
| B．Fulgurite can be dissolved in water. |
| C．It is essential for the formation of DNA. |
| D．Schreibersite and phosphorus mineral can be found in it. |
| A．To report. | B．To explain. |
| C．To discuss. | D．To compare. |
| A．Entertainment. | B．Health. |
| C．Science. | D．Education. |
【推荐3】Pre-school children who spend time together take on one another's personalities, a new research has found. The study shows that environment plays a key role in shaping people's personalities. While genetics still forms the central part of the human psyche (心理), the research finds that personality traits (特征) are "contagious" (传染的) among children. "Our finding flies in the face of common assumptions that personality can't be changed," said Dr. Jennifer Neal, co-author of the study.
The researchers studied the personalities and social networks of two pre-school classes for a full school year. One of the classes was a set of three-year-olds, and the other a set of four-year-olds. Children whose friends were hard-working or outgoing gradually took on these personality traits over time. Psychology expert Dr. Emily Dublin said kids are having a far bigger effect on each other than people may realize.
The new study is not the first to explore the contagious effects of personality traits. A 2015 psychology study found that rudeness at work can be contagious as it travels from person to person "like a disease". The study found that seeing a boss being rude to an employee was enough to cause people to be rude to those around them.
The researchers questioned 6,000 people on the social "climate" in their workplaces, which included offices, hotels and restaurants. They found 75 percent of those who took part said they had been treated rudely at least once in the past year. And the study also suggests that merely seeing other people being subjected to rudeness made it more likely that a person would treat their colleagues in the same way. Rudeness could include leaving someone off an invite to a company event, sending unkind emails, finding fault with others or failing to give praise.
Dr. Torkelson believes companies need to be more aware of the harm that rudeness in the workplace can do as it can damage the working environment. She said better training could help to fight against the problem.
1. What does the underlined part "flies in the face of" in Paragraph1mean?| A．Leads to. | B．Results from. |
| C．Goes against. | D．Agrees with. |
| A．Their parents. | B．Their friends. |
| C．The researchers. | D．The psychologists. |
| A．Ignoring the faults of co-workers. |
| B．Not sending emails to workmates. |
| C．Seeking praise from colleagues and bosses. |
| D．Not inviting a colleague to a company party. |
| A．One's personality is hard to change. |
| B．One's personality is shaped by genes. |
| C．One's personality traits can spread to others. |
| D．One's personality traits can change overnight. |
| A．a science report | B．a study guide |
| C．a school textbook | D．a technical journal |
