1 . Imagine a warm spring day 66 million years ago. These could have been the very last moments of the dinosaur era when a city-sized asteroid struck Earth, killing off three quarters of all species on the planet. According to a study published in Nature on Feb 23,the asteroid hit in springtime.
Scientists have long been confused over the time of year the asteroid hit, and how some animals managed to survive while dinosaurs didn’t, according to USA Today.
Researchers in 20l9 discovered fossilized fishes in North Dakota that died shortly after the asteroid hit Earth. They examined the fossils with a particle accelerator and found out there was seasonal growth on the bone. All fish bone cell densities and volumes can indicate the season. Because the accelerator also could capture the sizes, researchers were able to determine when in the year the asteroid hit, Dennis Voeten told USA Today.
“I think spring puts a large group of the late Cretaceous biota in a very unprotected spot because they were out and about looking for food, tending to offspring after the winter,” Melanie During, the main author of the study.
In the Southern Hemisphere, it was autumn. Therefore, life in the Southern Hemisphere was a lot more prepared for this event.
It is unclear whether small animals in the Northern Hemisphere actually did worse than those in the south. There is evidence that Northern Hemisphere turtles were wiped out in the asteroid strike, after which their habitats were later repopulated by turtles from the south, Voeten told The Guardian.
Nothing much larger than a house cat survived the asteroid impact and many species would have been killed whenever it hit, Daniel Field, a professor at the University of Cambridge, told The Guardian.
1. Which probably helps find the time of year the asteroid hit?| A．The types of fossilized fishes. | B．The location of fossilized fishes. |
| C．The number of fish fossils in the area. | D．The volume and density of the fish bone cells. |
| A．The season of the hit. | B．The size of asteroid. |
| C．The group size of species. | D．The body shape of animals. |
| A．Chances of survival depended on it where the species lived at the time. |
| B．Many species could have survived the asteroid strike but for the season. |
| C．Many species had little chance to survive even if it was a different season. |
| D．Animals from the Southern Hemisphere were less affected by asteroid strikes. |
| A．The Science behind the Asteroid | B．Occurrence of the Natural Disaster |
| C．The Effect of Dinosaurs’ Extinction | D．New Research on the Asteroid Strike |
2 . Mars is truly a fascinating planet for those of us here on Earth.
The Red Planet has the largest volcano in the solar system-Olympus Mons.
Mars also has an atmosphere, but it is very thin and made up mostly of carbon dioxide. Because of its thin atmosphere and greater distance from the Sun, Mars is much colder than Earth.
Scientists believe that studying Mars can help answer some of the key questions about our planet Earth, or even the universe.
| A．It is roughly 27 kilometres high. |
| B．Missions to Mars have never been easy. |
| C．Mars, however, today has no active volcanoes. |
| D．The temperature at the planet’s surface varies widely. |
| E．However, Mars does have weather, with clouds and winds. |
| F．China will continue to explore the mysteries of the universe. |
| G．It is one of the few planets that we can see with our own eyes. |
3 . The US space agency NASA has revealed an astonishing picture revealing new secrets of the Earth’s home galaxy (星系), the Milky Way. The sun is just one of hundreds of billions of stars that form the huge shape of our galaxy. Our solar system sits in an outlying region but the new image focuses on the centre of the Milky Way, a “noisy” area because of all the crowded stars. Light from this region takes about 26,000 years to reach Earth. For comparison, light takes just eight minutes to reach us from the sun.
The researchers use the data collected by two telescopes that see the sky in ways that are very different from the visible light our eyes can see to form the new image. Most of the data comes from 370 different pictures taken over the past 20 years by NASA’s Chandra X Observatory. This satellite telescope detects X-rays out in space. X-rays are a from of radiation that is sent out when violent events heat matter to temperatures of millions of degrees. Other data comes from the MeerKAT telescope in South Africa, which can detect radio waves from space. These waves have much less energy than X-rays. They are usually produced by cooler material, such as huge clouds of gas between the stars.
The brightest sources include neutron stars which are the cores of huge stars that ran out of fuel and collapsed to city-sized balls of super hot matter. Many neutron stars and black holes jet out gases that appear in the picture as purple streaks (斑纹). Powerful magnetic fields in the area cause the jets to bend as they get further from their source. Astronomer Dr Daniel Wang, who has worked on the image over the past year, said the new picture described “a violent or energetic ecosystem”.
What may be the best title for the text?
| A．Our galaxy’s violent heart | B．An attempt to travel in outer space |
| C．Radio waves from outer space | D．Stars’ purple streaks |
4 . It seems that we are one step closer to finding alien life and maybe a future home for humanity. Scientists from NASA have found a new solar system filled with planets that look like the Earth and could even support life.
The group of seven planets, which orbits a star called Trappist-1, is 39 light years away from the Earth in the constellation of Aquarius (水瓶座). And three of them are in the “habitable zone” — the area around a star where water is most likely to be found. This is important because water is necessary for life.
“This is an amazing planetary (行星的) system, not only because we have found so many planets, but because they are all surprisingly similar in size to the Earth”, astronomer Michael Gillon from the University of Liege in Belgium told The Independent.
Trappist-1 is a “dwarf star (矮星)” which is colder and shines dimmer than our sun. If a person were on one of the seven planets, everything would look a lot darker than usual. The amount of light heading toward our eyes would be about 200 times less than we get from the sun, according to The Independent.
Because of that, Trappist-1, together with many other dwarf stars, was never on the list of places where scientists looked for alien life. But Michael Gillon, lead researcher behind the discovery, decided to give dwarf stars a chance. He built a telescope in Chile to observe 60 of the closest dwarf stars, and it turned out that Trappist-1 was worthy of the effort.
The researchers hope that they can spend more time watching the newly found planets to learn more about them. Even though more research is needed before determining whether these planets could really support life, the discovery is still encouraging. It shows just how many Earth-size planets could be out there.
“The discovery gives us a hint that finding a second Earth is not just a matter of if, but when,” NASA scientist Thomas Zurbuchen told The Telegraph.
1. Why is this new planetary system amazing?| A．The size of the planets is similar to that of the Earth. |
| B．It has the same number of planets as our solar system. |
| C．Scientists have found alien life in the new solar system. |
| D．The planets are more suitable for humans to live than the Earth. |
| A．Stronger. | B．More powerful. | C．Less bright. | D．Less beautiful. |
| A．It is impossible to find alien life on the planets of Trappist-1 and other dwarf stars. |
| B．Scientists did not find a good place to observe dwarf stars according to the passage. |
| C．Trappist-1 and other dwarf stars don’t provide as much heat and light as our sun can. |
| D．Scientists have observed dwarf stars, but they failed to find the possibility of survival. |
| A．Scientists have found a second Earth. |
| B．People will move to another Earth soon. |
| C．Scientists are planning to explore another planet. |
| D．A new solar system may become home for humans. |
5 . Two high school students have identified four new planets in distant space about 200-light-years from Earth, making them “the youngest astronomers” to make such a discovery.
Kartik Pingle, 16, and Jasmine Wright. 18, who both attend schools in Massachusetts, participated in the Student Research Mentoring Program (SRMP). With the help of Tansu Daylan, an MIT doctor for Astrophysics and Space Research, the students studied and analyzed data from the Transiting Exoplanct Survey Satellite (TESS). Together they focused on Tess Object of Interest (TOI) 1233, a nearby, bright sun-like star and here they found four planets rotating（旋转）around the star. “We were looking to see changes in light over time,” Pingle explained, “the idea is that if the planet transits the star, or passes in front of it, it would periodically cover up the star and decrease its brightness.”
While studying 1233, Pingle and Wright had at least hoped to find one planet but were overwhelmed with joy when a total of four were spotted. “I was very excited and very shocked.” Wright said. “We knew this was the goal of Daylan’s research, but to actually find a multi-planetary system, and be part of the discovering team, was really cool.” Three of the newly discovered planets are considered as “sub-Neptunes”, which are gaseous, but smaller than the Neptune that lives in our solar system. While observing the planets, the team determined each one completes their orbit around 1233 every six to 19.5 days. However, the fourth planet is called a “super-Earth” for its large size and rockiness this one orbits around the star in just under four days.
“We have long been studying planets beyond our solar system and with multi-planetary systems, the two young students are kind of hitting the jackpot. They are really blessed.” Daylan said. “The planets originated from the same disk of matter around the same star, but they ended up being different planets with different atmospheres and different climates due to their different orbits. So, we would like to understand the basic processes of planet formation and evolution using this planetary system.”
Daylan added that it was a “win-win” to work with Pingle and Wright on the study. “As a researcher, I really enjoy interacting with young brains that are open to experimentation and learning and have slightest bias（偏见）.”he said, “I also think it is very beneficial to high school students, since they get exposure to cutting-edge research, and this prepares them quickly for a research career.”
1. How did the two students identify the four planets？| A．By helping professor Tansu Daylan with the data. |
| B．By analyzing the change of brightness of star 1233. |
| C．By studying Neptune that lives in our solar system. |
| D．By interacting with other young talented brains. |
| A．It was made by two high school students. |
| B．It was made with an innovative approach. |
| C．It was meant to be made by Tansu Daylan. |
| D．It found the largest number of planets at a time. |
| A．Making a discovery difficultly. | B．Achieving the goal easily. |
| C．Succeeding in something luckily. | D．Performing a task carefully. |
| A．It allows the scientists to work with young people without prejudice. |
| B．It equips future astronomers with better researching abilities. |
| C．It provides more perspectives and thus boosts more discoveries. |
| D．It arouses students’ interest in exploring the unknown universe. |
6 . If Mars were the popular kid in school, Venus (金星) would be the unwelcome one sitting in the corner, largely ignored. Venus has nearly the same mass and size as Earth, but being closer to the sun, it gets nearly twice as much heat from the sun.
However, instead of having a climate that is just a warmer version of Earth’s, Venus’s surface and atmosphere are unbearable: clouds of sulphuric acid (硫酸) blanket the planet, while at ground level, it is hot enough to melt lead. Despite this, there is now a sign that Venus may harbour life. Jane Greaves at Cardiff University, UK, and her colleagues recently detected (发现) phosphine (磷化氢) in Venus’s atmosphere, with one potential explanation that it is the by-product of biology. That is because the only way this gas is made on Earth is in laboratories or by microbes (微生物). Though this doesn’t mean it was produced by life on Venus, attempts to find non-biological explanations for its presence have so far failed. Our best way of confirming or rejecting the possibility of life on Venus is to go and have a proper look. While Mars has been the focus of interplanetary (行星间的) exploration efforts lately, the phosphine discovery lets people look at Venus in a new light. As NASA administrator Jim Bridenstine tweeted: “It’s time to prioritize Venus.”
In the months and years to come, computer simulations(模拟) will be used to further study the possible chemistries of the atmosphere on Venus. More laboratory experiments will be conducted to try to identify other ways the phosphine there could be produced. However, there is no guarantee that these efforts will reveal the true nature of this substance on Venus. A newly-proposed strategy is to directly sample the atmosphere and surface of Venus. By doing so, we would be able to take direct measurements of phosphine.
The discovery of phosphine in Venus’s atmosphere is a great accomplishment. The scientific efforts may be just what we need to finally refocus on this neglected world. Possibly, the quiet kid in the corner may get the last laugh
1. Which description about Venus is NOT true?| A．It has the unbearable surface and atmosphere. |
| B．It has nearly the same mass as Earth. |
| C．It is almost as large as Earth. |
| D．It has a warmer Earth-like climate. |
| A．This kind of gas is very common. | B．There might exist signs of life. |
| C．Many products can be made with it. | D．Experiments were once conducted there. |
| A．The necessity to analyse phosphine. |
| B．The power of computer simulations |
| C．The importance of observations. |
| D．The approaches to exploring phosphine |
| A．Casual | B．Doubtful. | C．Supportive. | D．Unclear. |
7 . The temperature of the Sun is over 5,000 degrees Fahrenheit at the surface, but it rises to perhaps more than 16 million degrees at the center. The Sun is so much hotter than the Earth that matter can exist only as a gas, except at the core. In the core of the Sun, the pressures are so great against the gases that, despite the high temperature, there may be a small solid core. However, no one really knows, since the center of the Sun can never be directly observed.
Solar astronomers do know that the Sun is divided into five layers or zones. Starting at the outside and going down into the Sun, the zones are the corona, chromosphere, photosphere, convection zone, and finally the core. The first three zones are the regarded as the Sun’s atmosphere. But since the Sun has no solid surface, it is hard to tell where the atmosphere ends and the main body of the Sun begins.
The Sun’s outermost layer begins about 10,000 miles above the visible surface and can be seen during an eclipse (日食) such as the one in February 1979. Other time, the corona can be seen only when special instruments are used on cameras and telescopes to shut out the glare of the Sun’s rays.
The corona is a brilliant, pearly white, filmy light as bright as the full Moon. Its beautiful rays are a sensational sight during an eclipse. The corona’s rays flash out in a brilliant fan. The corona is thickest at the sun’s equator (赤道).
The corona rays are made up of gases streaming outward at tremendous speeds and reaching a temperature of more than 2 million degrees Fahrenheit. The rays of gas thin out as they reach the space around the planets. By the time the Sun’s corona rays reach the Earth, they are weak and invisible.
1. What is the second paragraph mainly about?| A．How the Sun evolved. |
| B．The structure of the Sun. |
| C．Why scientists study the Sun. |
| D．The distance of the Sun from the planets. |
| A．corona | B．chromosphere |
| C．photosphere | D．core |
| A．Paragraph 1. | B．Paragraph 2. |
| C．Paragraph 3. | D．Paragraph 4. |
8 . Earth is constantly being hit by space rocks. Several tons rain down on the planet each day in the form of dust. And larger strikes have created more visible features, including giant craters. But which of our planet’s extraterrestrial scars is the oldest?
Researchers reported on Tuesday in Nature Communications that they have pinpointed it, in Western Australia. It was caused by an impact more than 2.2 billion years ago. Interestingly, that timing roughly coincides with the end of one of our planet’s ice ages. An impact in the ice would have liberated an enormous amount of water vapor, the researchers suggest, perhaps enough to alter Earth’s climate.
The Yarrabubba impact structure, about a day’s drive northeast of Perth, isn’t much to look at today. The original crater, believed to have been roughly 40 miles in diameter, is long gone. That’s because the combined effects of wind, rain, glaciation and plate tectonics have washed several miles off the surface of the planet, effectively erasing the crater. The extent of erosion suggests that the impact structure is very, very old.
Existing clues yield “a pretty giant” age range of about a billion and a half years, said Timmons Erickson, a geochronologist at NASA Johnson Space Center in Houston and the study’s lead author. But Dr. Erickson knew that it was possible to do far better, by reading the tiny geological clocks that hide within rocks.
In 2014, Dr. Erickson collected roughly 200 pounds of granitic rocks from Yarrabubba. Back in the laboratory, based on a series of experiments, Dr. Erickson and his team calculated that the Yarrabubba impact occurred 2.229 billion years ago, with an uncertainty of 5 million years. The nextoldest impact structure, Vredefort Dome in South Africa, is over 200 million years younger.
The age of the Yarrabubba impact structure happens to line up with the end of an ice age, which makes for a compelling coincidence, Dr. Erickson said: “Would an impact event like Yarrabubba be enough to terminate a glacial time in Earth’s history?”
To help answer that question, the scientists modeled the effects of a roughly fourmilewide impact object striking ice sheets of different thicknesses. They found that more than 100 billion tons of water vapor would have been jetted into the upper atmosphere. Water vapor is an effective greenhouse gas; suddenly having much more of it in the atmosphere could have caused a warming that ended an ice age, the team suggested. That idea still needs to be tested with climate models, the researchers noted.
Christian Koeberl, a geochemist at the University of Vienna and not involved in the research, agreed. Inferring what might have happened to Earth’s ancient climate is “Where things get a lot more speculative,” he said.
1. Which of the following statements is TRUE?| A．Craters are formed when the Earth is struck by rocks. |
| B．The Yarrabubba impact is a very popular tourist attraction in Australia. |
| C．We cannot see the original crater of the Yarrabubba impact because of erosion. |
| D．The age of the crater can be accurately measured by the degree of the erosion. |
| A．Dr. Erickson has accurately measured Yarrabubba impact with his experiments. |
| B．A sudden release of much water vapor might have resulted in the ending of an ice age. |
| C．Sufficient evidence has proved that the Yarrabubba impact had ended an ice age. |
| D．Considering the uncertainty, Vredefort Dome might still hold the title of being the oldest. |
| A．He criticized the research for its inaccuracy. |
| B．He applauded the novelty of the researchers’ approach. |
| C．What happened to earth’ climate billions of years ago has come to light. |
| D．He acknowledged the difficulty involved in further investigations. |
| A．Earth’s Oldest Impact |
| B．How To Warm a Planet |
| C．Giant Craters On Earth |
| D．Earth’s Geological Erosion |
9 . Let’s go back to Venus
Phosphine (磷化氢) in Venus’ atmosphere could be a sign that life is there. The only way to find out for sure is to go have a look.
If Mars were the popular kid in school,Venus (金星) would be the nerd sitting in the corner, largely ignored. Despite its image, Venus is the brightest object in the sky after the sun and the moon, its orbit taking it closer to Earth than any other planet in the solar system. It has nearly the same mass and size as Earth, but being closer to our star, it gets nearly twice as much heat from the sun.
However, instead of having a climate that is just a warmer version of Earth’s, Venus’ surface and atmosphere are hellish: clouds of sulphuric (含硫的) acid blanket the planet while at ground level it is hot enough to melt lead. Despite this, there is now a sign that Venus may harbour life.
Jane Greaves at Cardiff University, UK and her colleagues recently detected phosphine in Venus’ atmosphere, with one potential explanation that it is the by-product of biology. That is because the only way this gas is made on Earth is in laboratories or by microbes. Though this doesn’t mean it was produced by life on Venus, attempts to find nonbiological explanations for its presence have so far fallen short.
Our best hope for confirming or rejecting the possibility of life on Venus is to go and have a proper look. During the cold war, the USSR sent more than a dozen missions to Venus, including several landers and a pair of balloons, but these ended well before the dawn of the 1990s. Likewise, NASA hasn’t launched a mission dedicated to Venus since the late 1980s. What’s more no US mission has plumbed the depths of its atmosphere and probed its surface since the Pioneer Venus missions that departed Earth in the 1970s.
Other countries have had more recent efforts: the European Space Agency’s Venus Express orbited the planet throughout the late 2000s and early 2010s, while Japan’s Akatsuki orbiter is exploring Venus right now. But these missions were ill-equipped for detecting phosphine or life.
While Mars has been the focus of interplanetary (太阳系内的) exploration efforts of late, with some space agencies focusing on landing more craft and even people on its surface, the phosphine discovery has people looking at Venus in a new light. As NASA administrator Jim Bridenstine tweeted:“Its time to prioritize Venus.”
In the months and years to come, computer simulations (模拟) will be used to further study the possible chemistries of the atmosphere on Venus. More observations will be made (and the old ones reanalysed) and laboratory experiments will be conducted to try to identify other ways the phosphine there could be produced. However, there is no guarantee that these efforts will reveal the true nature of this substance on Venus.
A new mission to directly sample the atmosphere and surface would be a watershed moment in planetary science. It need not only look for signs of life, but also answer some of our many questions about Venus, such as why it became so different to Earth and whether it was once habitable.
Some options to do this already exist. There are two NASA missions currently vying for approval. India aims to send an orbiter to Venus in 2023 and private company RocketLab also has plans to visit in that year, hopefully with a probe passing through the planet’s atmosphere.
The discovery of phosphine in Venus’ atmosphere is a great accomplishment. The scientific endeavour it has set in motion is as if a sleeping giant has awakened and it may be just what we need to finally refocus on this neglected world. The quiet kid in the corner may yet have the last laugh.
1. Venus is compared to the nerd sitting in the corner because ________.| A．it’s the brightest object in the sky after the sun and the moon |
| B．its mass and size shape its image as a quiet and neglected kid |
| C．Its orbit takes it close to Earth and the sun in the solar system |
| D．it has been neglected in recent interplanetary exploration efforts |
| A．Its hell-like climate rules out the possibility that there may be life on Venus. |
| B．It’s enveloped in clouds of sulphuric acid and its surface is hot enough to melt lead. |
| C．It has nearly the same mass and size as Earth and is closer to Earth than any other planet. |
| D．Getting about twice as much heat from the sun, its climate is a warmer version of Earth’s. |
| A．the phosphine discovery has shed new light on Venus |
| B．Mars has been the focus of interplanetary exploration efforts of late |
| C．Our best hope for confirming the possibility of life on Venus is to have a look |
| D．Previous missions to Venus have hardly borne significant scientific or biological results |
| A．It has called upon scientists to refocus on Venus. |
| B．It gives a clue as to how to make phosphine out of labs on Earth. |
| C．It has cleared away the doubt regarding whether Venus may habour life. |
| D．It has overturned scientists’ previous perception of how Venus’ atmosphere was formed. |
10 . How many things can you see in the night sky? A lot! On a clear night you might see the Moon, some planets, and thousands of stars.
But scientists believe there are some things in the sky that we will never see. We won’t see them with the biggest telescope in the world, on the clearest night of the year. That’s because they are invisible (看不见的). They’re the mysterious dead stars called black holes.
You might find it hard to imagine that stars die. After all, our Sun is a star. Year after year we see up in the sky, burning brightly, giving us heat and light. The Sun certainly doesn’t seem to be getting old or weak. But stars do burn out and die after billions of years.
As a star’s gases burn, they give off light and heat. But when the gases run out, the star stops burning and begins to die.
As the star cools, the outer parts of the star pull in toward the center. The star is squashed (挤压) into a smaller and smaller ball. If the star was very small, the star ends up as a cold, dark ball. If the star was very big, it keeps being squashed inward until it’s packed together tighter than anything in the universe.
Imagine if the Earth collapsed until it was the size of a tiny marble (玻璃球). That’s how tightly this dead star, a black hole, is packed. What pulls the star in toward its center with such power? It is the same force that pulls you down when you jump — the force called gravity. A black hole is so tightly packed that its gravity absorbs everything — even light. The light from a black hole can never come back to your eyes. That’s why you see nothing but blackness.
So the next time, you look up at the night sky, remember: there’s more in the sky than what meets the eye! Scattered (散落) in the silent darkness are black holes — the great mystery of space.
1. What might happen after a star dies?| A．The star might become a black hole. |
| B．The Earth might be hit by the star. |
| C．The sky might become much darker. |
| D．The gravity might totally disappear. |
| A．Its gases run out. | B．It hits other stars. |
| C．It gets too hot. | D．Its light fades away. |
| A．Folded. | B．Crashed. | C．Orbited. | D．Marched. |
| A．Most black holes are too far away. |
| B．We don’t have a powerful enough telescope. |
| C．Black holes can travel as fast as light. |
| D．Light can not escape a black hole’s gravity. |
