All evidence points to the fact that Mars once had flowing water, but numerous flybys, orbiters and landers have confirmed one undeniable fact — any liquid (液体的) water that was once on its surface is now long gone.
One idea, the Mars Ocean Hypothesis, suggests that Mars not only had some liquid water, but a lot of it. But the new study’s co-author Kun Wang says his team’s finding pours cold water on it.
“Mars’ fate (命运) was decided from the beginning.” Wang, an assistant professor of Earth and planetary sciences, said in a statement. That’s because the lower mass and gravity of Mars makes it easier for volatile (挥发) elements and compounds such as water to escape from its surface into space.
The researchers looked at 20 Martian meteorites (陨石) ranging in age from about 200 million years old to 4 billion years, dating back to a time when the solar system was still in the chaos of formation. The researchers analyzed water behaves in much the same way, indicating that most of it would have been lost to space during the formation of Mars.
The liquid water that did remain on the Martian surface carved out the riverbeds and other formations that we see there today, Wang says. But that water, too, would likely have disappeared had it not been trapped as ice at the Martian poles as the climate on the planet became colder, he notes.
“This does probably indicate a lower limit on size for a planet to be truly habitable,” Wang says, “Understanding that lower limit is important — there are lines of evidence that small planets are more common than big ones, so if the small ones are dry, then there are fewer habitable (适于居住的) worlds out there than we thought.”
1. What is the function of the first paragraph?| A．To present an argument. | B．To make a comparison. |
| C．To reach a conclusion. | D．To explain a concept. |
| A．Water is too easy to dry out. |
| B．The cold weather froze the water. |
| C．Flybys consumed most of the water. |
| D．The gravity of the Mars can hardly lock water. |
| A．Comparing results. | B．Listing figures. |
| C．Giving examples. | D．Raising questions. |
| A．We are in great need of water on earth. |
| B．They are trying to find suitable place for humans. |
| C．Mars is the destination to explore in the long run. |
| D．Mars is very significant for the health of the earth. |
相似题推荐
【推荐1】Have you ever wondered if you see the same colours as other people? Most people know what blue is when they see it. They call it "blue” because they were taught the word and connected it with what they saw. But how do you know what you see as blue isn’t someone else s red?
The ability to perceive (感知) different colours is up to receptors (接受器) in our eyes. Light waves hit these receptors and they react depending on which colour the light is, sending signals to the brain. The brain then reads these signals to determine which colour light the eyes are receiving.
Some people’s receptors are more developed than others. The inability of the receptor to feel the light waves correctly means that some people cannot tell the differences between similar colours.
Those with more developed receptors can see more colours. We sometimes hear people having an argument about whether something is dark blue or black. It might be because one person has stronger receptors to feel the light than another.
In the past, most scientists would argue that everyone saw colours in the same way. However, research was conducted on monkeys, in which their receptors were changed. This enabled them to see more colours than usual. Normally monkeys can only see blue and green, but the change allowed them to see red. Their brains automatically (自动地) got used to new colours. This suggests that our brains may adapt depending on our stimulus (刺激) and find new colors of the things we see. Colours could be a very personal experience, unique to everyone.
So, the next time you talk about your favourite colour, just remember if yours is blue and your friend says red, you two might actually be thinking about the same colour. What if everyone in the world has the same favourite colour, but just calls it different names?
1. What is Paragraph 2 mainly about?| A．How we perceive colours. |
| B．The inability to see colours. |
| C．What the brain does with signals. |
| D．The connection between receptors and light waves. |
| A．Some people cannot feel colours with their developed receptors. |
| B．The more light people feel, the weaker receptors they have. |
| C．People with poor receptors usually have colour weakness. |
| D．People who have strong receptors can see dark blue. |
| A．To test the monkeys with colours. |
| B．To develop the receptors of humans. |
| C．To enable monkeys to find more colors. |
| D．To prove everyone sees colours in a different way. |
| A．A film review. | B．A science magazine. |
| C．An art magazine. | D．A business newspaper. |
【推荐2】It’s been 50 years since the beginning of bar codes. Scanning an item at checkout is something we take for granted in this age of convenience.
On March 31, 1971, a historic meeting took place in New York City. The meeting agreed to create a system to uniquely identify every single product, calling it the Global Trade Item Number (GTIN) the core of bar codes, according to El Mudo, a Spanish newspaper.
In the past five decades, bar codes have provided many conveniences for commerce. “The next generation of bar codes, such as QR codes can hold vastly more information. Their use, for example, can tell consumers if a product contains allergens (过敏原) or if it is organic.
| A．Time has proved it a great decision. |
| B．It gives consumers a greater level of trust. |
| C．What information does a bar code contain? |
| D．When do we scan a bar code on the product? |
| E．We can thank the game-changing technology for that. |
| F．The numbers can indicate where that product is identified, |
| G．It allows the first digitization in the control of the goods for sale. |
【推荐3】Anyone who deals with teens knows how difficult the adolescent years can be. Teens are always known to do wild and dangerous things.
Scientists discovered that though our brains are almost at their full size by the age of six, they are not fully developed. Now, scientists have found our brains continue to change till age 25.
The studies confirm teens are more likely to take risks and behave in extreme ways. One way the brain does this is by changing the way teens think of danger and reward (回报). When teenagers think about rewards, their brains produce more chemicals that create pleasure than adult brains would.
Besides, researchers found it makes social connections especially rewarding. Generally, teenagers have an intense need to meet new people and think the youth may one day control the world they live in. As it’s still developing, a teenage brain can change to deal with new situations.
Some people think that this hunt for greater rewards can sometimes lead teenagers to go to extremes.
| A．It is hard for the teens to adapt to new situations. |
| B．The result is the changeable actions seen in teens. |
| C．Therefore, it connects social rewards with more pleasure. |
| D．This makes the rewards seem more important than the risks. |
| E．However, it is of great benefit for teenagers to go for rewards. |
| F．The teen brain inspires teenagers to help prepare for the school life. |
| G．These things were thought to be down to the foolishness of the young. |
【推荐1】We live in a world of countless reminders, and constant push notifications (通知). Every service seems to be competing for our attention all the time. As it turns out, all this distraction may come at a massive cost, but you don’t even realize it.
The findings from new research at Ohio State University were published in the Journal of Experimental Psychology: Human Perception and Performance. Dozens of participants were given a simple-sounding task. Look at a screen of four colored squares. One will be outlined in white-pay attention to that one. After these squares flash on the screen for a mere tenth of a second, pick the color that you remember from a color wheel.
Despite the rapid speed of such work, the human brain excels (擅长) at this task. “People are quite good at this, surprisingly good!” says Julie Golumb, associate professor of psychology at Ohio State University.
They got quite good at it, to a point. Researchers threw a wrench by introducing an intentional distractor. Of the four squares, one would be outlined in white, but then another — the distractor — would be surrounded in white dots. Despite being instructed to ignore the distractor, subjects just couldn’t help it. Most of the time, they still recalled the color. But about20% to 30% of the time, they actually reported the distractor color as the correct one, unaware of the error.
As Golumb emphasizes, findings like these are a big deal. We’ve long known balancing too many tasks can slow down our thinking. But the fact that it can literally recolor our memories should give us pause, because there’s not a fundamental difference between colored squares and real versus fake news headlines on social media．
“If you’re trying to pay attention to multiple things, you’re not going to be as good at if it were one at a time,” she says. “We’ve known for a long-time multitasking might slow you down, but our research shows, it’s not just you might be slowed down; it might affect what you’re perceiving in the moment.”
1. What task were the participants given?| A．Distinguish different colors of squares. |
| B．Put the squares of a color into groups. |
| C．Pick out the square color outlined in white. |
| D．Figure out what you remember from a color wheel. |
| A．Assessed the experiment. |
| B．Added the difficulty. |
| C．Overturned the result. |
| D．Discovered the truth. |
| A．Making a comparison. |
| B．Giving examples. |
| C．Following time order. |
| D．Making classifications. |
| A．Suspicious. | B．Unconcerned. | C．Optimisti | D．Negative. |
【推荐2】Seeds on Ice
Close to the North Pole，remote and rocky Plateau Mountain in the Norwegian archipelago of
Svalbard seems an unlikely spot for any global effort to safeguard agriculture. In this cold and deserted environment，no grains，no gardens，no trees can grow. Yet at the end of a 130-meter-long tunnel cut out of solid stone is a room filled with humanity’s most precious treasure, the largest and most diverse seed collection—more than a half-billion seeds.
A quiet rescue mission is under way. With growing evidence that unchecked climate change-will seriously affect food production and threaten the diversity （多样性） of crops around the world，the Svalbard Global Seed Vault （地窖） represents a major step towards ensuring the preservation （贮藏） of hundreds of thousands of crop varieties. This is a seed collection, but more importantly, it is a collection of the traits found within the seeds：the genes that give one variety resistance to a particular pest and another variety tolerance for hot，dry weather.
Few people will ever see or come into contact with the contents of this vault. In sealed boxes，behind multiple locked doors，monitored by electronic security systems, enveloped in below—zero temperatures, and surrounded by tons of rock, hundreds of millions of seeds are protected in their mountain fortress. Frozen in such conditions inside the mountain, seeds of most major crops will remain viable for hundreds of years, or longer. Seeds of some are capable of retaining （保留） their ability to grow for thousands of years.
Everyone can look back now and say that the Seed Vault was a good and obvious idea, and that of course the Norwegian government should have approved and funded it. But back in 2004, when the Seed Vault was proposed, it was viewed as a crazy，impractical, and expensive idea.
We knew that nothing would provide a definite guarantee. But we were tired，fed up，and frankly scared of the steady, greater losses of crop diversity. The Seed Vault was built by optimists who wanted to do something to preserve options so that humanity and its crops might be better prepared for change. If it simply resupplied seed gene banks with samples those gene banks had lost, this would repay our efforts.
The Seed Vault is about hope and commitrnent - about what can be done if countries come together and work cooperatively to accomplish something significant，long-lasting，and worthy of who we are and wish to be.
1. According to the passage, the Seed Vault is ___________.| A．a tunnel where the collected seeds are displayed |
| B．a stone room that contains the seeds of endangered crops |
| C．a seed gene bank that stores diverse seeds for future agriculture |
| D．a lab where researchers study how to maintain the diversity of crops |
| A．mature | B．clean |
| C．alive | D．valuable |
| A．how the seeds are preserved | B．where people keep the seeds |
| C．why the seeds are protected | D．what people do to study the seeds |
| A．the Seed Vault offers a solution to climate change |
| B．most countries took part in rescuing the seed varieties |
| C．the Seed Vault guarantees to prevent the loss of crop diversity |
| D．many people originally considered building the Seed Vault unwise |
【推荐3】The year 2114 will be an eventful one for art. In May of that year in Berlin, the philosopher-artist Jonathon Keats’ “century cameras” — cameras with a 100-year-long exposure time — will be brought back from hiding places around the city to have their results developed and exhibited. Six months after that, the Future Library in Oslo, Norway, will open its doors for the first time, presenting 100 books printed on the wood of trees planted in the distant past of 2014.
As Katie Paterson, the creator of the Future Library, puts it: “Future Library is an artwork for future generations.” These projects, more than a century in the making, are part of a new wave of “slow art” intended to push viewers and participants to think beyond their own lifetimes. They aim to challenge today’s short-term thinking and the brief attention spans of modern consumers, forcing people into considering works more deliberately. In their way, too, they are fighting against modern culture — not just regarding money, but also the way in which artistic worth is measured by attention.
In a similar fashion, every April on Slow Art Day, visitors are encouraged to stare at five works of art for 10 minutes at a time — a tough task for the average museum visitor, who typically spends less than 30 seconds on each piece of art.
Like the Future Library, the century cameras are very much a project for cities, since it’s in cities that time runs fastest and the pace of life is fastest. “Since I started living in a city, I’ve somehow been quite disconnected,” Anne Beate Hovind, the Future Library project manager, who described how working on the library drew her back to the pace of life she knew when she was growing up on a farm in her youth, told The Atlantic magazine.
1. According to the first paragraph, what will NOT happen in 2114 ?| A．A camera which was produced 100 years ago will be exhibited. |
| B．The Future Library will be open to the public for the first time. |
| C．Photos with a 100-year exposure time will be developed and exhibited. |
| D．Books printed on the wood of trees planted in 2014 will be displayed. |
| A．They consider works deliberately. | B．They spend little time on works. |
| C．They spend much money on works. | D．They stare at works for 10 minutes at a time. |
| A．To advocate creating works of art slowly. |
| B．To protect works of art from being damaged. |
| C．To promote works of art for modern culture. |
| D．To encourage people to consider works more deliberately. |
| A．It’s discouraging. | B．It’s awful. | C．It’s developed. | D．It’s busy. |
【推荐1】China's space program took a major leap recently when it successfully landed the Zhurong rover(登防车) on Mars marking the country's first landing on another planet. Teams then rolled the rove onto the Martian ground and begin a mission to search for evidence of water and signs of past life.
The touchdown makes China the second county in history to land a rover on the surface of Mars. After months in orbit around the red planet, the Tianywen-l Spacecraft released the Zhurong rover for a landing in Utopia Planitia, a vast plain that may once have been covered by an ancient Martian ocean.
“Landing safely on Mars is a huge challenge, especially for China's first soft landing attempt," said Long Xiao, a scientist at the China University of Geosciences, "But it is a necessary step for Mars and deep-space exploration."
Mars is significantly harder to land on than the moon, says Michel Blanc at the Research Institute in Astrophysics and Planetology in France. But China has had a series of successful lunar missions that prepared it for a Mars landing.
China will openly share the data from Tianwen-1 and Zhurong the same way it has shared data from its lunar exploration missions, Long says, benefiting scientists around the world.
The mission will also set the stage for China’s next planned voyage to Mars---a sample---return attempt scheduled to launch around 2028.Beyond Mars, the country has plans to launch a Jupiter probe(探测仪), including a possible landing on the moon Callisto, to collect samples from a near-Earth asteroid(小行星), and to send a pair of spacecraft toward the edges of the solar system.
“In the age of ocean exploration, China has a history of Zheng He's voyages to Southeast Asia and Africa," says Zhang Xiaoping at the Macau University of Science and Technology, referring to early 15th-century explorations. Zhang views China's Mars mission as a continuation of these Ming Dynasty journeys.
1. What can be known about the Zhurong hovers?| A．It lands in an ocean on Mars. |
| B．It provides evidence of life on Mars. |
| C．It was transported to Mars by Tianwen-1. |
| D．It marks the first human exploration on Mars. |
| A．Lunar exploration is more difficult than Mars exploration. |
| B．China made successful soft Manding attempts on Mars before. |
| C．China's latest space exploration can benefit the whole world. |
| D．Mars exploration is the significant step to prepare for lunar exploration. |
| A．The specific task of Tianwen-1. |
| B．The background of Mars exploration. |
| C．The timeline of China's lunar exploration. |
| D．The plan for China's further space exploration. |
| A．To compare him with other explorers in history. |
| B．To highlight the significance of Mars exploration. |
| C．To praise his great achievement in ocean exploration. |
| D．To inspire the readers' imagination in space exploration. |
【推荐2】Out-of-control SpaceX Rocket
A SpaceX rocket is now headed directly for the moon after spending almost seven years flying through space, experts say. The rocket was originally launched to send a space weather satellite to the Lagrange point— a gravity-neutral position four times farther than the moon and in direct line with the sun.
At this phase, it did not have enough fuel to return to Earth’s atmosphere. But meanwhile it lacked the energy to escape the gravity of the Earth-Moon system.
As for whether the collision (相撞) could be viewed from Earth, Gray says it will probably go unobserved.” Even if it hit on the near side of the moon, the impact occurs a couple of days after New Moon, which was hardly observable, he added, “to me, the impact was not a big deal.”
| A．So the rocket has been following a somewhat chaotic orbit since. |
| B．Nevertheless, space enthusiasts believe the impact could provide valuable data. |
| C．It was part of SpaceX’s space exploration programme. |
| D．But after completing a long burn of its engines, the rocket’s second phase became a problem. |
| E．The exact spot that the rocket will hit remains unclear. |
| F．The lunar phase reveals the passage of time in the night sky. |
【推荐3】Besides “wow” and “great”, what else would you say when flying over the Earth in space? Samantha Cristoforetti, the first Italian female astronaut in space, posted several lines of a famous ancient Chinese composition on Twitter to share her joy.
She first wrote in Chinese, and then attached an accurate translation of the lines in both Italian and English to help more people understand. “Looking up, I see the immensity of the cosmos; bowing my head, I look at the multitude of the world. The gaze flies, the heart expands, the joy of the senses can reach its peak, and indeed, this is true happiness,” it says. Two days before she landed on Earth, the beauty of space and Chinese literature resonated on her Twitter account. Before long, her posts went viral on Twitter with thousands of retweets, likes and replies.
The text she quoted is from the Preface to Poems Composed at the Orchid Pavilion,a Chinese calligraphy masterpiece by Wang Xizhi (303-361) of the Eastern Jin Dynasty (317-420). She also attached three photos taken in space of China’s Bohai Bay and the day-night view of Beijing. “The poem and views are both magnificent as well as healing. If everyone could enjoy the same sight, a lot of pain in the world would be ‘dissipated’,” one user comments.
As the first Italian female astronaut in space, Cristoforetti carried out her first space mission on Nov 23, 2014. In 2022, she started the second mission in April and returned to Earth on Friday night after a 127-day stay in orbit.
Cristoforetti has also been active in Sino-European cooperation in the field of manned spaceflight. She was a working group member with Chinese counterparts to define and implement cooperation in the field of astronaut operations. When not traveling for work, she is an eager reader and has a great passion for languages. Speaking clear Chinese, Cristoforetti once told the media that the teams from China and Europe were working very well together in the field of astronaut training.
1. What is the result of Cristoforetti’s post online?| A．The birth of a masterpiece. |
| B．A trend of journey to space. |
| C．An instant hot issue on Twitter. |
| D．Different translations of the lines. |
| A．Relieved. | B．Caused. |
| C．Increased. | D．Recognized. |
| A．Cristoforetti’s devotion to her career. |
| B．Cristoforetti’s language learning strategies. |
| C．The leadership Cristoforetti plays in her team. |
| D．The possible motivation for Cristoforetti’s post. |
| A．A female astronaut becomes online star |
| B．A Chinese poem gets popular abroad |
| C．Literature conveys the beauty of space |
| D．An Italian astronaut promotes Sino-European cooperation |
