Mars rover (火星车) Zhurong, part of China’s Tianwen-1 Mars exploration mission, has provided key observational evidence of liquid water at low Martian latitudes (纬度), the warmest regions on the red planet, according to a new study.
Previous studies found evidence of a large amount of liquid water on early Mars, but climate changes led to very low pressure and water vapor content (水汽含量), making it difficult for liquid water to exist on the present-day planet. Scientists believe that water can now only exist there in solid or gaseous forms.
However, robots on Mars have found that salty liquid water can appear in the summer at high latitudes on Mars. But evidence of liquid water at the planet’s low latitudes, where surface temperatures are highest, is still lacking. Findings from the Zhurong rover, whose landing site was in a low-latitude region of Mars, now fill that gap.
A group of more than 20 researchers at the Chinese Academy of Sciences has since used data obtained by cameras and detectors on the rover to study the surface features and material compositions of sand hills in the landing area.
Researchers explained that salts in sand hills cause frost and snow to melt at low temperatures to form salty liquid water. When it dries, it leaves trace on the surface of the planet. They also said the sand hills Zhurong found were formed about 400,000 to 1.4 million years ago. The exchange of water vapor between the higher and lower latitudes during this period led to repeated wet environments at low Martian latitudes, followed by the frequent occurrence of salty water when temperatures dropped in the region.
The discovery provides key proof of liquid water at Martian low latitudes, where surface temperatures are relatively warm and more suitable for life than high latitudes. It also provides information for the design of future exploration strategies for Mars rovers to search for existing life on Mars, researchers said in the study.
1. What is the purpose of paragraph 2 and 3?| A．To show the effects of climate changes. |
| B．To stress the contribution of the discovery. |
| C．To introduce the findings of previous studies. |
| D．To present the lack of evidence of water on Mars. |
| A．The exchange of water vapor. |
| B．Frost and snow melted by salt. |
| C．Water vapor at lower temperatures. |
| D．Water collection from the wet environment. |
| A．Zhurong looks for signs of existing life. |
| B．Zhurong plans to search for signs of water. |
| C．Zhurong finds new evidence of water on Mars. |
| D．Zhurong lands its robotic arms on the red planet. |
| A．It explores Mars landing strategies. |
| B．It proves the existence of solid water. |
| C．It finds an environment good for lives. |
| D．It helps future Mars exploration plans. |
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【推荐1】As for long-distance holidays, there are some unique destinations that actually offer you great value for your money, even if you’re on a budget.
Tokyo, Japan
Food lovers should head to this busy city which has the lowest cost for dining out — you could even bag a three-course evening meal for two, with a bottle of house wine, for just under £ 34. For sightseeing there are plenty of free museums and attractions, while tour bus ticket prices start from as little as £ 11.56.
Bangkok, Thailand
Thailand's capital is second to none as the best value long-distance city. Although there isn’t a huge difference across all prices compared to the other cities, it is accommodation that really makes it stand out. I you’re only stopping for a long weekend, then make sure to check out the awe-inspiring The Grand Palace, a complex of breathtaking temples.
Beijing, China
The Chinese capital took third spot with a total basket price of £ 337.49. If you only do one cultural day out during your stay, make it a trip to The Forbidden City. There are some seriously beautiful and delicate buildings from the Ming and Qing dynasties, not to mention they're home to priceless artificial objects from China's historical milestones.
Dubai, UAE
Although Dubai does have a reputation for being quite the splurge (挥霍金钱) when it comes to holidays and if you’re going to addict yourself to a spot of shopping or hit the roller-coasters, it actually provides quite good value for what you pay. The city also offers some cheaper prices across its museums, galleries and attractions as well as airport transfers.
1. What can you enjoy in Tokyo, Japan?| A．Eating out cheap. | B．Free bus ride. |
| C．Visiting galleries free. | D．Priceless man-made objects. |
| A．Tokyo. | B．Bangkok. | C．Beijing. | D．Dubai. |
| A．Dubai is famous for house wine producing. |
| B．Historical buildings spread everywhere in Dubai. |
| C．Being on vacation in Dubai costs tons of money. |
| D．The roller-coasters there are the best in the world. |
【推荐2】Dogs wag (摇摆) their tails in different directions depending on whether they are excited and wanting to move forward or threatened and thinking of moving back, a study has found.
Researchers in Italy examined the tail wagging behaviour of 30 dogs, catching their responses to a range of stimuli (刺激物) with video cameras. To conduct the study they chose 15 male dogs and 15 female ones aged between one and six years. The dogs were all family pets whose owners had allowed them to take part in the experiment at Bari University. The dogs were placed in a large wooden box with an opening at the front to allow for them to view various stimuli. They were tested one at a time.
The researchers led by Professor Giorgio Vallortigara of the University of Trieste found that when the dogs were shown their owners — a positive experience — their tails wagged energetically to the right side. When they were shown an unfamiliar human they wagged to the right, but with somewhat less enthusiasm. The appearance of a cat again caused a right-hand side wag, although with less intensity again. The appearance of a large unfamiliar dog, similar to a German shepherd, changed the direction of tail wagging to the left. Researchers supposed the dog was thinking of moving back. When the dogs were not shown any stimuli they tended to wag their tails to the left, suggesting they preferred company. While the changes in the tail wagging were not easily noticed without the aid of video, it was thought that the findings could help people judge the mood of dogs. Computer and video systems, for example, could be used by professional dog trainers to determine the mood of dogs that they were required to approach.
1. The video cameras were used to catch the dogs’ responses because ________.| A．it was easier to catch the dogs’ response changes in the tail wagging |
| B．the dogs were put in the wooden boxes and tested one at a time |
| C．they enabled the dogs’ owners to know about their dogs’ habit |
| D．the dogs wagged their tails in different directions when they were in different moods |
| A．surprise | B．worry | C．hate | D．excitement |
| A．wag to the right | B．wag to the left |
| C．not wag at all | D．wag to the left and then to the right |
| A．the trainers | B．the dogs | C．the systems | D．the researchers |
| A．to help people judge the mood of dogs | B．to train dogs for their owners |
| C．to help dogs find company | D．to help people choose their pet dogs |
【推荐3】Find your favorite. While many athletes are good at several sports, there will usually be one they are best at. Which sport are you most drawn to? Your favorite will make your work seem like play as you become a professional athlete.
Learn that even though you love the sport that is your favorite, it won’t be easy to become a professional athlete. You must be not only very talented (有天赋的), but also very serious. You must have the drive and dream to keep you going on. This needs a strong will. You’ll need a positive feeling.
Train long and hard, starting at a very young age. Little league, private lessons, high school and college teams can all help you to become a professional athlete. Of course, training will be different depending on the sport you choose. Any sport will need long hours and years of practice if you want to make a living as a professional athlete.
Study all the strategies (策略)and rules of your game. Watch videos of your performances. Look for your weak areas so you can work on improving.
Take care of your body by eating well and getting enough rest. Good nutrition (营养)and good rest will help to keep your body healthy. Nutrition and rest also play a key role in keeping your mind smart. Stopping smoking will also help keep your body in good health.
Be a person of honesty. You’ll be a role model for young children everywhere you go.
1. What should we do to become a professional athlete according to paragraph 1?| A．Work like play all day. | B．Play all kinds of sports. |
| C．Learn to play and have enough rest. | D．Learn what sport is our favorite. |
| A．Train hard but not too long. | B．Learn their weak points by watching videos. |
| C．Give up smoking and eat a lot. | D．Watch the videos of the sport. |
| A．A strong will. | B．Training hard and long. |
| C．Good diet and rest. | D．Dream and interest. |
| A．Ways of Being a Professional Athlete | B．Why Become a Professional Athlete |
| C．How to Protect Athletes | D．Professional Athletes’ Talent |
【推荐1】A pair of businessmen are attempting to start a new human spaceflight company that, instead of launching rockets, will lift civilian passengers into the sky tied to a high-performance balloon.
Space Perspective aims to carry a capsule of eight passengers at a time, hanging from a balloon, 100, 000 feet above Earth. The balloon and capsule will gently rise for about two hours at 12 mph, floating along for another two hours as passengers enjoy refreshments and a view of the Earth below, and then descend back down at 12 mph and land in either the Gulf of Mexico or the Atlantic Ocean.
The goal is to make the flights as accessible and affordable to as many people as possible, one day possibly hosting weddings. Co-founders Jane Poynter and Taber MacCallum, who are married, said they expect prices to be around $125, 000 for a single ticket. “Everybody should be able to see the Earth from space, “ Poynter said. “We want them to really be able to experience what astronauts talk about, looking down at the Earth in that blackness of outer space. ”
But passenger flights are still some time away.
Hoping to perform its first test flight in early 2023, Space Perspective joins the groups of developing companies working to create an industry that can send paying passengers to the edges of space, generally thought to begin about 50 miles off Earth’s surface. Space Perspective’s balloon will reach about 20 miles.
Passengers will need very little training before taking a ride with Space Perspective, MacCallum said. During the flight, the inside of the capsule will be pressurized, and temperature will be controlled. Onboard there will be a pilot, paired with another down on Earth, who can also control the craft. A new balloon, which will be filled with hydrogen, will be used for each flight and materials from it recycled. The capsule will be able to be reused on many missions.
Presentations of the spacecraft, to be named Spaceship Neptune, show a large capsule with a circle of seats facing out to a row of windows. Poynter and MacCallum said a bar, a bathroom and an clear windowed roof at the top of the capsule will be combined into the design.
1. Which of the following can replace the underlined word “descend" in Paragraph 2?| A．Decrease. |
| B．Sink. |
| C．Dive. |
| D．Fall. |
| A．Challenging. |
| B．Mysterious. |
| C．Sustainable. |
| D．Cheap. |
| A．Space Perspective plans to fly passengers in early 2023. |
| B．Space Perspective enables everybody to see the Earth above. |
| C．Space Perspective is to reuse the balloon and the capsule. |
| D．Space Perspective intends to transport common people into sky. |
| A．To advertise a service. |
| B．To present a scene. |
| C．To introduce a project. |
| D．To share an adventure. |
【推荐2】Have you ever wondered how astronauts clean their clothes in space? They wear their underclothes, and everything else, until they cannot take the dirt and smell anymore. Then, they throw them away.
NASA wants to change that. This would mean the end to throwing away lots of dirty clothes every year. Up to now, they simply had to put them with other waste in old supply ships to burn up in the atmosphere. NASA is working with the US company, Procter Gamble (P＆G), to learn how best to clean astronauts’ clothes in space. They could use the clothes for months or even years, just like on Earth.
P＆G announced that it would send detergent (洗涤剂) and dirt removal experiments to the space station later. The battle against dirty and sweaty clothes in space has begun. It is not a small problem, especially as the US and other countries plan to establish bases on the Moon and Mars.
Rocket storage space is small and costly. So, why waste it on new clothes if they could keep their old clothes looking and smelling fresh? An astronaut needs 68 kilograms of clothes in space per year. The clothes use a lot of storage space, especially on a three-year Mars mission.
Space station astronauts exercise two hours every day to fight the effects of weightlessness on their bodies. That quickly leaves their workout clothes sweaty, smelly and hard.
In its first experiment, P＆G would send up detergent made just for space. Scientists would then see how the compounds in the detergent react to six months of weightlessness. At the same time, P＆G is developing a washer-dryer machine that could operate on the Moon or even Mars. It would use small amounts of water and detergent.
1. What does the underlined word “that” in paragraph 2 refer to？| A．Washing clothes. | B．Getting rid of clothes. |
| C．Burning off clothes. | D．Changing clothes. |
| A．Saving room in the rocket. | B．Extending the stay in space. |
| C．Avoiding space rubbish. | D．Keeping the astronauts healthy. |
| A．Hard work. | B．Lack of gravity. |
| C．Few clothes to change. | D．Daily physical training |
| A．To have better sales. | B．To help astronauts wash clothes. |
| C．To experiment with its functions in space. | D．To test the washer-dryer machine out. |
【推荐3】NASA's Jet Propulsion(喷气推进) Laboratory (JPL) attracted Marlyse Reeves from an early age. Growing up in Pasadena, California, in JPL's backyard, Reeves developed a love for everything related to outer space, and the lab was a regular destination for school field trips. Even as a child, Reeves, now as an MIT senior, knew she wanted to work in the space industry. Her love of space was cultivated at home, too. At MIT, Reeves quickly found her place in the Department of Aeronautics and Astronautics (航空航天系).
As a junior, Reeves was selected to participate in the GordonMIT Engineering Leadership Program. The program focuses on leadership for engineers—people who may have high technical IQs but who may be not good at expressing themselves. Reeves holds the point that in industry, people have to communicate with other engineers—to explain their ideas and fit into the organizational structure.
In the second year of the program, students become coaches for the new students, which means a team coach observes, and instructs the younger group. So Reeves thinks it's really the secondyear students who are guiding the firstyear students into how they can improve as leaders.
Reeves has been with Women in Aerospace Engineering (WAE) since its beginning in her sophomore year. The group builds a community for women in all aspects of aeronautics. Last month, Reeves helped organize the first WAE Day, an event for 18 high school girls in the Boston area to come to MIT to learn about aerospace engineering. Reeves says events like these are especially important for exposing young women to the possibilities of the field.
Just as she says, “Being a person who has gone into the aerospace industry and has seen the lack of women, there are often times when I am the only female in the room. I think it's important for young women and girls to have role models, and just see that there are women doing it. I have met a lot of strong female role models for myself in industry... A lot of our events are open to men as well. We want to build a community of people who support women in aerospace.”
1. What can we learn from the first paragraph?| A．Reeves seldom visited JPL at an early age. |
| B．Reeves became interested in space from childhood. |
| C．Reeves is now a new student studying at MIT. |
| D．Reeves would like to study in the Department of Mathematics at MIT. |
| A．It is aimed at developing engineers' leadership. |
| B．It focuses on increasing students' technical skills. |
| C．It tends to improve students' observation abilities. |
| D．It aims to train excellent engineers for MIT in advance. |
| A．She thinks the industry is prejudiced against women. |
| B．She thinks women have a higher IQ than men in the field. |
| C．She believes having role models has a positive effect on women. |
| D．She feels it is difficult for women to become successful in the field. |
| A．Because it's a girl's dream. |
| B．Because it makes her a leader. |
| C．Because it helps women experience more about aeronautics. |
| D．Because it can strengthen the community. |
