An international team of researchers has revealed new evidence for the possible existence of liquid water beneath the south polar ice cap of Mars.
The researchers, led by the University of Cambridge, used spacecraft laser-altimeter (激光高度计) to measure the shape of the upper surface of the ice cap to identify its patterns in height. They then showed that these patterns match computer model predictions for how a body of water beneath the ice cap would affect the surface.
Their results agree with earlier ice-penetrating radar (穿冰雷达) measurements that were originally interpreted to show a potential area of liquid water beneath the ice. There has been debate among scientists over the liquid water interpretation from the radar data alone, with some studies suggesting the radar signal is not due to liquid water.
The results provide the first independent line of evidence, using data other than radar, that there is liquid water beneath Mars’ south polar ice cap.
“The combination of the new evidence, our computer model results, and the radar data makes it much more likely that at least one area of liquid water beneath the ice cap exists on Mars today, and that Mars must still be geothermally (地热) active in order to keep the water beneath the ice cap liquid.” said Professor Neil Arnold, who led the research.
Like Earth, Mars has thick water ice caps at both poles, roughly equivalent in combined volume to the Greenland Ice Sheet. Unlike Earth’s ice sheets, however, which are underlain by water-filled channels and even large lakes beneath the ice cap, the polar ice caps on Mars have until recently been thought to be frozen solid all the way to their beds due to the cold Martian climate.
The analysis revealed a 10~15 kilometre long, wave shaped surface comprising a depression and a corresponding raised area. This is similar in scale to surface areas over the lakes beneath the ice cap on Earth.
1. What is spacecraft laser-altimeter aimed to do?| A．To test chemicals in water. | B．To adjust the computer model. |
| C．To map the surface of the ice cap. | D．To measure the size of Mars. |
| A．They firmly believed it. | B．They held different views. |
| C．They reached a conclusion. | D．They ignored the practice. |
| A．They are only found at the south pole. | B．They are frozen solid to their beds. |
| C．They are shaped by ground lakes. | D．They are similar to those on Earth. |
| A．An Unexpected Field in Space Studies | B．An Advanced Technique to Explore Mars |
| C．New Evidence for Liquid Water on Mars | D．Human Optional Home in the Near Future |
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【推荐1】The future is electric. That means it will need a lot of batteries, motors and wires. That, in turn, means a lot of minerals with which to build them. Great times, then, for prospectors (探矿者), and particularly for any who think they can increase the efficiency of their profession. Several firms are applying artificial intelligence to the process, both to improve the possibility of mining and to detect underground ore (矿石) bodies that are invisible to current techniques.
KoBold Metals in California, Earth Al in San Francisco and Verai in Boston are small fish at the moment But at least one bigger fish-Rio Tinto, an Australian-British firm-is also keen. They are gathering lots of geological (地质的), geochemical and geophysical data to feed software models. These, they hope, will spot patterns and draw inferences about where to sink new mines. Some of the data are new. But a lot were kept in the archives (档案室) of national geological surveys and journals of geology or sat in the form of rock cores in various sheds around the world.
KoBold has transformed archive data from around the world, many of which are on paper and some of which go back to the 19th century, into machine-usable form. That has permitted it to build maps of areas of interest all over Earth’s surface Some of those maps are used to train the company’s Al models. Others are used to test those Al models’ effectiveness by checking how good they are at predicting known ore deposits (矿藏) on maps that they have not previously seen. If they pass, they can be let loose on (放手做) under-explored places of interest and suggest the most effective places to drill. Thanks to that, last year KoBold announced its discovery of’ a rich copper deposit, in Zambia.
In spite of the success, Kurt House, KoBold’s boss, observes that many of the exploration projects fail to turn into actual mines. AI therefore has plenty of room to improve. However, by greatly expanding the volume of rock which can be searched, it will enable new mining in our own countries, lessening the need to rely on other countries for future supplies.
1. Why is it great times for prospectors?| A．There is a high demand for plenty of minerals. |
| B．They want to increase their working efficiency. |
| C．There are many invisible underground ore bodies. |
| D．They can use AI to improve the possibility of mining. |
| A．Newly collected geological data. | B．Geological data in the archives. |
| C．Data in the form of rock cores. | D．Data about the software models. |
| A．By transforming machine-usable archive data. |
| B．By building maps of all the known ore deposits. |
| C．By using AI models trained with maps of’ mines. |
| D．By drilling the under-explored places of interest. |
| A．We can fully rely on AI to locate actual mines. |
| B．AI could help improve mineral exploration. |
| C．Al will help increase the number of ore deposits. |
| D．We should join other countries on new mining. |
【推荐2】Top Trends in IT for 2021
Quantum computing
Like its name suggests, quantum computing is based on the principles of quantum theory.
Different from traditional computers, quantum computers can handle complex operations at speeds much faster than traditional computers without needing as much energy.
Quantum computers have proven to be especially helpful during the pandemic of COVID-19. For instance, they were used to search for potential vaccines and find other treatments to help affected people. Its potential will be explored more in 2021.
Working from home
"There is no real going back to normal,” Gerard Grech, CEO of networking company Tech Nation, told Wired magazine, "The pandemic has given us an opportunity to rethink how we work and why.”
After working from home for much of 2020, some companies noticed an increase in productivity, when their employees worked remotely. Not only that, but providing this option can also help cut down operating costs for companies.
This is great news for workers, too, as many people have wanted more flexibility with their work. More types of workspaces with work from home options will grow rapidly this year.
Cybersecurity
Cybersecurity has recently become more important because people are more dependent on working online. In fact, according to Forbes, hackers took advantage of the pandemic and increased cyber-attacks worldwide.
One solution is the cybersecurity mesh. This method puts a security barrier around each individual instead of around the company or organization.
Going into 2021 and beyond, cybersecurity will become important as our world becomes even more digitalized and interconnected.
1. How is a quantum computer different from a traditional one?| A．A quantum computer takes less space. | B．A quantum computer needs more energy. |
| C．A quantum computer operates at a higher speed. | D．A quantum computer costs less. |
| A．An improvement in productivity. | B．A decrease in operating costs. |
| C．Flexibility with one's work. | D．An increase in working time. |
| A．Defending companies against cyber attacks. | B．Protecting individuals from cyber attacks. |
| C．Setting a security barrier around organizations. | D．Providing individuals with a digitalized world. |
【推荐3】From rolling hills to mountain ranges, views make any road trip memorable, but for blin d passengers this is part of the experience they miss. Motor company Ford tries to change that. It teamed up with GTB Rom a and AedoProject—to develop a technology that will give those unfortunate passengers a way to feel nature’s beauty through their car windows.
The prototype (原型) of the smart car window has a device with an outside-facing camera. With just a press of a button, the system takes a picture of the current view. The colorful picture is then turned into an image with different shades of grey through, LED lights, which vibrates (震动) differently. As the finger passes over different regions of the image, its shaking movements provide feedback through the sense of touch to the person using it. The smart window also comes with a voice assistant that uses AI to identify the scene and help the passengers get information on what they’re seeing.
“As the prototype started taking shape, we realized we were giving birth to a completely new language that would give blind people a new chance to visualize and experience traveling,” Federico Russo.-one director of GTBRoma, said. “When the idea was at its first stage, we looked for suppliers all around the world to make it come to life.” He believes the technology can be employed not just in cars. “It could be introduced into schools and in stituations for blind people as a tool that could be used in multiple ways.”
The technology may show up in a Ford autonomous vehicle. It’s known that the company is testing their technology and future business model and struggling to figure out how an autonomous vehicle gives different passengers the details needed to get from one destination to another. It’s unclear when this technology will be made available. However, the idea of building something for the less advanced is indeed a kind and influential action.
1. How does the smart car window work?| A．By sorting shaking movements. | B．By recording the view with a camera. |
| C．By translating scenery into vibrations. | D．By presenting different shades of colors. |
| A．It will have wide application. | B．It will be used in schools first. |
| C．It will be tested around the world. | D．It will understand different languages. |
| A．How to explore their future business model. |
| B．How the technology is applied to everyday life. |
| C．How to produce autonomous cars in large numbers. |
| D．How an autonomous vehicle provides route information. |
| A．AI-based Window Adds Fun to Road Trips |
| B．Ford Develops a System for the Blind to Drive |
| C．Smart Window Lets Blin d Passengers Feel Views |
| D．Technology Makes Blind People’s Trip Enjoyable |
【推荐1】From the moa in New Zealand to the dodo in Mauritius (both of these two flightless birds have died out), the arrival of humans has often spelled extinction for tasty but previously isolated animals. Many scientists had assumed that the woolly rhinos (长毛犀牛) suffered the same thing. But Love Dalén, a professor at the Centre for Palaeogenetics in Stockholm. and Edana Lord, one of Dr Dalén's PhD students, are not so sure.
Until recently, information on the story of this great ice-age animal had been limited to the fossilized bones (骨骼化石). In the past couple of decades, however, scientists have learned to use a richer source of information： ancient genomes (基因组). By itself, DNA breaks down quickly, attacked by water and sunlight. But DNA covered in bones and teeth can survive longer, especially if those bones and teeth are themselves in permanent frozen land. It was this sort of DNA that enabled Dr Dalén and Ms Lord to investigate the woolly rhinos' disappearance.
Working with a team of colleagues, the researchers obtained DNA from 12 woolly rhino bones collected from permafrost in Siberia. Analyzing the genetic diversity of the bones, the researchers found that rather than declining as humans arrived, the population of rhinos remained stable from 29,000 years ago to 18,500 years ago, a few thousand years before they died out. Perhaps the people who met the animals found them distasteful. Or perhaps the rhinos were simply too dangerous to hunt with their simple weapons.
On the other hand, the animals' decline lines up suggestively with a rapid period of global warming that began around 14,700 years ago. The researchers argue that this was the more likely cause of the animals' disappearance. This time, it seems, it was Mother Nature who did it.
1. What probably caused the extinction of the moa and the dodo?| A．Human activity. | B．Geographical disasters. |
| C．Lack of food. | D．Climate change. |
| A．By testing DNA itself. |
| B．By collecting fossilized bones. |
| C．By analyzing ancient genomes. |
| D．By studying the permanent frozen land. |
| A．They disappeared quickly. |
| B．They decreased in numbers. |
| C．They were hunted as foo |
| D．They co-existed with humans long |
| A．Mother Nature Is Actually the Killer |
| B．What Killed Woolly Rhinos? |
| C．Woolly Rhino Bones Were Found in Siberia |
| D．What Happened to Woolly Rhinos? |
【推荐2】The term “Iron Man” has many connotations, including references to a song, a comic book icon, even a movie. Yet only one definition of the term truly lives up to its name: the Ironman Triathlon held annually in Hawaii, a picturesque setting for a challenging race, which demands amazing physical prowess and the ability to swim, bike, and run a marathon, all in less than 12 hours with no break. Very few individuals are up to the task.
However, Gordon Haller is a notable exception. Growing up in the 1950s, Haller developed an interest in many sports categorized as endurance athletics and welcomed their physical demands. As he pursued a degree in physics he drove a taxi to pay the bills, but competitive training proved his passion. So when he heard about the race in 1978, the first year it was held, he immediately signed up.
The race originated in a somewhat amusing way. The members of the two popular sports clubs, the Mid-Pacific Road Runners of Honolulu and the Waikiki Swim Club of Oahu, had a long-standing and good-natured debate going over who made better athletes: runners or swimmers. However, some local bikes thought both clubs were wrong, claiming that they, in fact, deserved the title. Wanting to settle the dispute once and for all, they decided to combine three separate races already held annually on the island into one massive test of endurance. Thus, the Waikiki Roughwater Swim of 2.4 miles, the Around-Oahu Bike race of 112 miles, and the Honolulu Marathon of 26.2 miles were all put together to form the Ironman Triathlon.
Haller was one of only fifteen competitors to show up that February morning to start the race. He quickly scanned the few pages of rules and instructions, and on the last page he discovered a sentence that would become the race’s famous slogan: “Swim 2.4 miles! Bike 112 miles! Run 26.2 miles! Brag for the rest of your life!” Haller took that to heart, and at the end of the day, he became the first Ironman champion in history. ____
In the approximately thirty years since that very first race, the Ironman has become a tradition in Hawaii and now boasts approximately 1500 entrants every year. The competitors who complete the race don’t have to be the first across the finish line to claim success: just finishing is a victory onto itself.
1. The “Iron Man” in the passage above refers to ________.| A．a folk song | B．a theatre movie |
| C．a book icon | D．a sport event |
| A．He had a great interest in all kinds of sports. |
| B．He was a member of the Waikiki Swim Club of Oahu. |
| C．He became a taxi driver after he graduated from school. |
| D．He was a champion in the first Ironman Triathlon. |
| A．muscles | B．skills | C．balance | D．reaction |
| A．Twelve other people also finished the race that day. |
| B．No women raced this year, but that was soon to change. |
| C．There were points in the race when Haller thought he couldn’t possibly finish. |
| D．Haller’s physical strength enabled him to do what no one else in the past had accomplished. |
| A．The level of interest the race attracts in the present day. |
| B．The way the current race is different from the race that Haller ran in 1978. |
| C．How the victors respond when they cross the finish line. |
| D．Why 1500 people would be willing to compete in such a difficult race. |
【推荐3】Most people who’ve stayed up all night know the “tired and nervous” feeling the next day. The body might be exhausted, but the brain feels active or even crazy. Even after these changes fade away, sleep loss can have a strong anti-depression effect on people for several days.
To figure it out, a team of biologists from Northwestern University looked at the effects of sleep loss in mice. In the beginning, they created a depressed state in all the mice by repeatedly giving them small shocks. In response to these shocks, the mice entered a depressive-like state and eventually stopped trying to escape their cages. Subsequently, some were allowed to sleep while others were forced to stay up. Later, they tested the mice’s response to shocks again. They found that after this sleepless night, the mice that had stayed up were less depressed and showed more attempts to escape the shocks.
What causes these changes in mice? To see how the mice’s brains responded to their sleepless night, the researchers measured dopamine neuron (神经元) activity. They saw that mice lacking in sleep showed higher dopamine activity in three regions: the prefrontal cortex (前额叶皮质), nucleus accumbens (伏隔核) and hypothalamus (下丘脑).
To figure out which areas were related to the mice’s anti-depression effect, they silenced dopamine reactions in each of these areas of the brain. The anti-depression effect disappeared in mice when the team silenced the dopamine input in the prefrontal cortex, while it continued to exist when they do the same to the other two regions. That’s why Yevgenia Kozorovitskiy, the leading researcher, says that this region may be important in relieving depression.
Based on the belief that transitions between a depressed state and a non-depressed state are influenced by the brain’s ability to reorganize connections, Kozorovitskiy and her team looked at individual neurons in the prefrontal cortex for signs of growth. They saw evidence of the new connections, suggesting that dopamine had reconnected neurons in the mice brains to maintain their mood for several days. Kozorovitskiy says this work may help future studies on depression treatment, but whether it’ll cure depression remains to be seen.
1. What is the purpose of the first paragraph?| A．To present a fact. | B．To introduce a study. |
| C．To make a prediction. | D．To analyze a phenomenon. |
| A．The mice staying up were constantly depressed. |
| B．The mice with sleep loss gave up escaping cages. |
| C．The mice with enough sleep didn’t react to shocks. |
| D．The mice sleeping less were in anti-depression state. |
| A．Uncovering causes of mice’s changes. | B．Testing new treatment for depression. |
| C．Finding mice’s reaction to environment. | D．Assessing the amount of dopamine input. |
| A．Optimistic. | B．Objective. | C．Doubtful. | D．Negative. |
【推荐1】United Airlines is aiming to have electric aircraft flying regional routes by the end of the decade, part of the company’s goal to fully reduce its carbon footprint to net zero by 2050.
Those battery-powered aircraft are being developed by Swedish start-up Heart Aerospace, from which United Airlines placed an order for 100 planes in July 2021. United Airlines has pushed heavily into a variety of lower-emission forms of aviation, not only announcing plans to buy electric air taxis and vertical aircraft, as well as hydrogen-electric engines but also investing in the companies behind the advanced technologies.
“We cannot continue doing and operating our business the way we do; it is important that we change it, and the way we’ re going to change it is through investing in technology,” Mike Leskinen, United Airlines Ventures president, said in an interview as part of CNBC’s ESG Impact virtual conference on Thursday. “Existing technology is going to either cause us to fly less, which is an unacceptable alternative, or continue with a carbon footprint, which we believe is equally unacceptable,” Leskinen said.
Heart Aerospace, which recently redesigned what will be its first electric aircraft which is now called the ES-30, plans to have the planes enter service in 2028, said Anders Forslund, the company’s CEO and founder.
The 30-passenger planes will be driven by electric motors with battery-derived energy, allowing the planes to have a fully electric range of 200 kilometers. The planes will also include a reserve- hybrid engine powered by sustainable aviation fuel, allowing it to have an extended range of up to 400 kilometers with a full flight.
United Airlines could potentially offer those shorter routes not only with greater frequency but at a lower cost. Leskinen said. “As we adopt electric aircraft, I think the cost for a 30-seat aircraft or a 50-seat aircraft, as the industry evolves, is going to be lower than a traditional aircraft,” he said. For small cities, this means they are “going to get either service that they didn’t have before or greater frequency of service,” he added.
1. What message did Mike Leskinen try to deliver in paragraph 3?| A．Economic benefits should come first. |
| B．Environmental protection should come first. |
| C．Economy and environment should be equally valued. |
| D．Economy and environment can’t be balanced. |
| A．They will offer short-distance flights. | B．They will fly faster than traditional ones. |
| C．They were developed by United Airlines. | D．They each can hold 30 passengers at most. |
| A．Their security performance. | B．Their potential benefits. |
| C．Their operating modes. | D．Their possible problems. |
| A．ES-30 Will Be Driven by Electric Motors |
| B．The Airline Industry Faces New Opportunities |
| C．Heart Aerospace Plans to Develop Electric Planes |
| D．United Airlines Aims to Have Electric Planes Flying |
【推荐2】Over the next 50 years, we are going to send more and better robots to Mars.
Before people can visit Mars, we need to invent a spaceship that can take us there.
The moon is much closer, and we were there many years ago. Over the next 10 years, we are going to work on building a new spacecraft.
Once we return to the moon, we are going to build a station so that people can live and work on the moon for months at a time. This is important so that we have a place to start from when we want to visit Mars.
By the time you are old enough to be an astronaut, we will have people spending months on the moon. By the time you are old enough to be a commander of a space mission, we will be taking trips to Mars. By the time your kids are old enough to be astronauts, we may have people living on Mars. Wouldn’t it be cool to get a postcard from someone who was building a house on Mars?
| A．Mars is very faraway. |
| B．People will go to live on Mars one day. |
| C．Wouldn’t it be cooler if it was you who sent the postcard? |
| D．Using this craft, we will practice the skills we need to go to Mars. |
| E．Those robots will send back better pictures, maps, and weather reports. |
| F．It would be possible for us to go to Mars in a spacecraft in the near future. |
| G．This is also important because it gives us practice with living away from Earth. |
【推荐3】In 1957, the first spaceship was sent up to travel around the earth, and it started the time of Space Age. Years later, astronaut s traveled around the earth and men walked on the moon. Today, space exploration continues, and governments try hard to make new discoveries. However, there has been one big change: private companies are entering the field of space travel.
Space X has been triumphant in space travel. They made the spaceship to work for the International Space Station(ISS). Elon Musk, the boss, wants to do more. He hopes that Space X will be able to send people to Mars by 2025.
Another fan of space travel is Sir Richard Branson. His company is called Virgin Galactic. He wants to open space travel to everyone. The company has sold almost 700 future trips to space at a high price. The tourists come from countries all over the world and are of different ages.
These private companies are lucky. They don’t have to wait for money from the government. However, they also have problems and accidents happen sometimes. In 2014,a Virgin spaceship fell down during a test flight. The 39-year-old pilot was killed. In 2016, another Space X spaceship exploded. No one was hurt, but important parts of it were lost.
The exploration of the space continues. Some companies want to take people to the moon and back someday. Others want to take people to Mars. The possibilities are endless. Maybe in our lifetime, those dreams will come true.
1. What does the underlined word “triumphant” in Paragraph 2 mean?| A．Successful. | B．Expensive. | C．New. | D．Busy. |
| A．Astronaut s first traveled around the earth in 1957. |
| B．Private companies do better than the government. |
| C．Virgin Galactic hopes to send people to Mars by 2025. |
| D．Space X is a name of a company owned by Elon Musk. |
| A．Disappointed. | B．Supportive. | C．Satisfied. | D．Uncaring. |
| A．Language learning. | B．Economy development. |
| C．Space exploration. | D．Sports & Health. |
