Mars may seem like a dry, desolate place, but the red planet transforms into an otherworldly wonderland in winter, according to a new video shared by NASA.
It’s late winter in Mars’ Northern Hemisphere, where the Perseverance rover and Ingenuity helicopter are exploring an ancient river delta (三角洲) that once fed into Jezero Crater billions of years ago.
As the planet’s main feature, dust drives Martian weather, but the planet is no stranger to snow, ice and frost. There are two types of snow on Mars. One is the kind we experience on Earth made of frozen water. The thin Martian air and sub-zero temperatures means that traditional snow changes from a solid directly to a gas, before touching the ground on Mars.
The other type of Martian snow is carbon dioxide based, or dry ice, and it can land on the surface. A few feet of snow tends to fall on Mars in its flat regions near the poles. “Enough falls that you could snowshoe (穿雪鞋走路) across it.” said Sylvain Piqueux, a Mars scientist at NASA’S Jet Propulsion Laboratory in Pasadena, California, in a statement.
So far, no orbiters(轨道飞行器) or rovers have been able to see snow fall on the red planet because the weather phenomenon only occurs at the poles beneath cloud cover at night. The cameras on the orbiters can’t peer through the clouds, and no robotic explorers have been developed that could survive the freezing temperatures at the poles, which can be as low as minus 120 degrees Celsius.
However, the Mars Climate Sounder instrument on the Mars Reconnaissance Orbiter can detect light that’s invisible to the human eye. It has made detections of carbon dioxide snow falling at the Martian poles. The Phoenix lander, which arrived on Mars in 2008, also used one of its laser instruments to detect water-ice snow from its spot about 1,600 kilometers away from the Martian north pole.
Thanks to photographers, we know snowflakes on Earth are unique and six sided. Beneath a microscope, Martian snowflakes would likely look a little different. “Because carbon dioxide ice has a symmetry (对称) of four, we know dry-ice snowflakes would be cube-shaped (立方体的), ” Piqueux said. “Thanks to the Mars Climate Sounder, we can tell these snowflakes would be smaller than the width of a human hair.”
Ice and carbon dioxide-based frosts also form on Mars, and they can occur farther away from the poles. The Odyssey orbiter (which entered Mars orbit in 2001) has watched frost forming and turning to a gas in the sunlight, while the Viking landers spotted icy frost on Mars when they arrived in the 1970s.
1．What can we learn about the snow made of frozen water on Mars?| A．It contains lots of dust. | B．It makes the Martian air thick. |
| C．It keeps its form stable while falling. | D．It can hardly be seen on the Martian ground. |
| A．The freezing temperature. | B．The thickness of clouds. |
| C．The changing weather pattern. | D．The distance from the poles. |
| A．Their smell. | B．Their size. | C．Their speed. | D．Their direction. |
| A．It Seldom Snows on Mars | B．It Is Much Colder on Mars |
| C．The Beautiful Winter on Mars | D．The Seasonal Changes on Mars |
In the spring sun, my aunt and I headed for her flower shop. Normally I would be delighted to help in her shop, but not recently because of Rosa. Rosa was my sister, just one month old, who was settled in my old bedroom. For ten years, the small room was full of my toys and books. But now it was transformed into her baby room, decorated like a garden with pinks and yellows. My space, my old life, was gone.
“Here we are!” We arrived at the shop, a wave of colour and sweet smell washing over me. My aunt said I could pick some flowers for Mum and Dad. I used to love this, but today I was so overcome with tiredness and envy. Why bother to bring them flowers when they were enjoying Rosa at home without me?
Silently I helped my aunt arrange flowers. “Your mum told me there hasn’t been much shut eye recently for any of you.” “Not much, since Rosa the alarm clock was installed (安装).” I complained with a huge yawn (哈欠).
“I remember having to creep (蹑手蹑脚地走) around like a worn-out mouse when your mum was a baby. I spent the first months hating her so much.” “But you and Mum seem so close,” I said, guiltily hiding away my envy of Rosa.
“Now we are. But it took me years to grow into the role of big sister. Few flowers blossom (绽放) overnight, you know.” She pulled me in for aside hug, glancing up at the clock, and suggested I take a walk outside.
Behind her shop was a field dotted with spring flowers. Stepping into the field, I began to pick little flowers. It was like gathering my childhood memories. I remembered how I’d sit with Dad, making flower chains, crowning (授予) each other with the silliest titles: Queen of Junk Food and King of Mess. My smile grew wider. The shining yellow flowers reminded me of the color in Rosa’s baby room. Was she awake? I wondered.
Suddenly I saw two familiar figures walking towards me.
Rosa was wide awake in her baby basket beside the picnic blanket.
Goldfish may seem like simple creatures swimming in a glass tank, but they possess a rather complicated navigation system, as discovered by researchers at the University of Oxford Led by Dr. Adelaide Sibeaux, the study aims to shed light on our understanding of how fish, and potentially humans, estimate distances using what could be described as an internal GPS.
Writing in the journal Proceedings of the Royal Society B, Sibeaux and colleagues report how they created a tank in their experiment with 2cm-wide black and white vertical stripes (条纹) on the walls, connected by similar stripes across the floor. The team trained nine goldfish to swim a set distance of 70cm and then return to their starting point when waved at. The experiment aimed to investigate how the fish would estimate this distance without any gestures, under different patterns.
Over multiple trials, the goldfish averaged a swim distance of 74cm, give or take 17cm, when presented with the vertical 2cm-wide stripes. However, when the stripe pattern was altered to either narrower vertical stripes, checked patterns, or horizontal stripes, the fish’s behavior changed significantly. Narrower vertical stripes led them to overestimating the distance by 36%, while horizontal stripes resulted in highly inconsistent estimations.
According to the researchers, the goldfish appeared to be using an “optic (光学的) flow mechanism” based on the visual density of their environment. They kept track of how frequently the vertical pattern switched between black and white to estimate how far they had traveled. The study suggests that different optic flow mechanisms are used by mammals, including humans, based on angular (有角度的) motion of visual features. The study implies that the use of visually based distance information could have emerged early in the evolutionary timeline.
“This study is novel because, despite knowing that fish respond to geometric information regarding direction and distance, we don’t know how they estimate distances,” Professor Colin Lever, although not involved in the study, said, “it’s exciting to explore fish spatial mapping because fish navigation evolved earlier and better than most mammals.”
1．Why did Dr. Adelaide Sibeaux conduct the study on goldfish?| A．To test the accuracy of goldfish’s internal GPS. |
| B．To create an advanced navigation system for humans |
| C．To uncover how an inbuilt GPS helps calculate distances. |
| D．To explore the relationships between goldfish and humans |
| A．People gestured the goldfish throughout the experiment |
| B．The tank was decorated with colorful background patterns |
| C．Goldfish tended to underestimate distances with horizontal stripes. |
| D．The change in the tank setting led to the goldfish's incorrect judgment. |
| A．optic flow mechanism is unique to humans |
| B．mammals developed flow mechanism long before goldfish |
| C．goldfish evaluated the distance with multidimensional visual information |
| D．visual density of the environment strengthened the locating ability of goldfish |
| A．Neutral. | B．Ambiguous. | C．Disapproving. | D．Favorable. |
At one time children made May Day baskets to celebrate spring and enjoy the rewards of giving surprising gifts to their beloved ones. When I was in perhaps the third grade, our class took on such an adventure. For several days, we worked on creating paper baskets. We cut colorful stripes of construction paper and wove them together, following our teacher, Miss Anderson. We cut and wove and glued. Then we decorated them with our crayons and more cutting and gluing. Finally, we fitted paper handles onto the tops so that we could secretly hang our creations on the doors of unsuspecting receivers: surely our mothers.
We were finished right on time. Miss Anderson brought armloads of flowers for us to use in stuffing our prizes. Lilacs and tulips and al the colorful flowers of spring. We had to wait until the day was nearly over before we were allowed to choose the flowers that were just right for our baskets. I chose the biggest, most beautiful blossoms, allowing myself to be selfish for the sake of my mother. Then we fidgeted (烦躁) away what remained of our day, waiting for the clock to tick down the minutes to our release.
Finally, mercifully, the bell rang! We threw on our coats, gathered our homework and our lunch boxes, tied on our scarves and then, carefully, we cradled our offerings of love and off we ran to our individual homes! I was so excited! I ran as fast as I could down the hill, across the street, up the block, heading home. I paused at the corner of my house, to catch my breath and savor the moment. Then I glanced down to admire my offering one last time before I hung it lovingly over the doorknob. Horrors! Shock, dread and depression! My flowers were gone! Apparently, bouncing out on my mad dash home, all that was left was a sad, messed-up, wrinkled little empty basket! I stood on the doorway and burst into mournful sobbing tears.
By and by, my mom came to the door to discover the source of the sorrow.
Soon, my newly-decorated basket was ready to be offered again.
Sandro was born and grew up in Milan. Until he was 13 years old, he never wanted to leave his hometown. But last year, Sandro’s father’s investment went bad, wiping out the family and sending his parents to prison. As a teenager under 16 years old, Sandro was forced to go to Newcastle in the northeast of England to stay with his uncle Lawrence.
Sandro had a lot of difficulties in the new environment. He didn’t like the food in England. Nobody could forecast the weather in Newcastle. He had to start learning the second foreign language in his new school. Pocket money was not enough as usual. Almost every subject was a challenge for him. Most importantly, he had no friends. It seemed nobody knew him and he knew nobody in the school.
On an early summer evening, when Sandro was going home alone from school as usual, a man called him from behind. Sandro turned around and saw Eddie, his PE teacher, standing in front of him.
“You know, the school will have a swimming competition next month. There will be all kinds of races. Will you participate?” Eddie asked.
Sandro took a look at Eddie with doubt and answered, “You sure? Me? No. I won’t. I can swim, but I’m slower than a snail.”
Eddie smiled and then said, “Yes. Indeed. You are, in breaststroke (蛙泳), in backstroke, and in butterfly, but not in freestyle. So join the freestyle race! 200-meter freestyle is the game suitable for you.”
Sandro was speechless at that moment. He had never known someone in the school was observing him and caring for him.
“I don’t think I can win anything,” Sandro was still a little puzzled.
“But you may get more recognition and consequently you can make some friends. That is more important than prizes,” Eddie responded immediately.
Having hesitated for a while, Sandro agreed to have a try.
Every afternoon for the next month, Sandro trained really hard.
Sandro dived into the pool confidently like other competitors.
My life is a juggling act. I’m a single mother of two sons. I’ve got a busy work schedule and limited resources. But there is one thing I don’t worry about: when I come home at night, dinner is already started. A typical weeknight at my house looks like this:
My youngest child is snapping (咬) the ends off the green beans. My eldest is mixing his secret salad dressing. The babysitter is working on the shopping list for tomorrow’s dinner-the kids want to make roasted noodles. I throw on an apron, send the babysitter home and join my kids in the dinner preparations.
Sounds too far-fetched for your home? It doesn’t have to be. If my family can do it. Any family can. Our meals weren’t always such happy group efforts. Seven years ago, my life was ruined by divorce, leaving me with a six-month-old baby and a very angry seven-year-old. I had no family nearby and very little money. The burden of rebuilding my career as a food writer and publicist while single-parenting my children on my own seemed difficult.
While I did my best to work during my youngest’s nap times, by day’s end I was physically and emotionally exhausted. Typically, I shooed(嘘)the boys out of the kitchen so I could perform yet another chore: making dinner. When I got the meal on the table, I left them to eat alone so I could have five minutes’ peace. Going back to my bedroom, I collapsed onto my bed and cried. I felt horrible about my family life and helpless to change it.
A year passed, but not much improved. At the end of my rope, one evening I gave some vegetable leaves at my youngest, who was then eighteen months old, so he’d leave me alone. It was incredible! He spent ten minutes happily tearing the leaves into little pieces. I was shocked at how he stayed on the task without saying a word.
Suddenly, I saw an opportunity. He wanted to help me, and I surely needed help.
Why not let them cook with me?
I stopped worrying about the mess and we started to laugh a lot.
If you feel deeply touched by Edward Hopper’s Nighthawks, a painting about depressed people having dinner in an urban restaurant, but unmoved passing by a real-world diner late at night, it may be because of what’s happening inside your body. New research suggests that bodily sensations (感觉) aren’t just a by-product of art’s emotional impact but a key pathway for experiencing something as “art” in the first place.
In a study involving 1,186 participants and 336 visual art pieces, researchers found that the strength of emotional experience caused by an artwork was connected with the strength of bodily sensations reported while viewing it. Emotions were measured using subjective reports, and viewers separately marked on a virtual human figure where and how they felt physical sensations. Eye tracking and participant surveys, meanwhile, evaluated viewers’ interest in the paintings and whether they considered them to be art. Bodily feelings’ scale was connected with both the strength of emotional experience and the evaluation of a piece as art. Sensations were most noticeable when participants said they felt empathy (the most commonly reported positive emotion) and when they cited “touching” and “moving” emotional experiences.
Negative emotions were uncommon, but reports of “sadness” were also linked to “touching” and “moving” experiences — and to a participant categorizing a work as art. Even the excitement from a haunted house (鬼屋) are ultimately experienced as positive, as we experience our hearts racing while we know we are safe,” says study lead author Lauri Nummenmaa, a researcher at the University of Turku in Finland. “Art likely employed similar mechanisms for making us feel good. It activates our autonomic nervous system, and in the peace and quiet of an art gallery this increased bodily activity feels good to us.”
Although the study used only subjective reports and didn’t measure objective physiological changes in the body, the data suggest that art perception (感知) involves awareness of the body’s internal state. Art may get under our skin to shift perception. Art may be in the whole body — not just the eye of the viewer.
1．How do the researchers measure participants’ strength of bodily feelings?| A．By tracking their eye movements. |
| B．By analyzing their personal reports. |
| C．By touching their different body parts. |
| D．By comparing their sensations with previous surveys. |
| A．To introduce categories of artworks. |
| B．To show how art makes us feel good. |
| C．To stress the importance of bodily emotion. |
| D．To explain how negative emotions are produced. |
| A．It is controlled by people’s expressions. |
| B．It changes the view point of participants. |
| C．It refers to the visual impact of the paintings. |
| D．It is related to what’s happening inside the body. |
| A．Technology. | B．Health. | C．Space & Physics. | D．Mind & Brain. |
One of the best things about new technology is how it makes the world more accessible to people with disabilities. Take Siri or Alexa, for example. They are a convenience or even a toy for most people. But if you’re blind, they’re potential life savers, capable of sending messages or receiving instructions, entirely through the power of your voice.
What’s truly exciting is how advances in artificial intelligence (AI) are enabling the creation of even smarter accessibility features. On the most recent Google Pixel phones, it’s possible to turn on a feature called “Live Captions”. This means that deaf people can easily watch videos — or even make video calls. And perhaps more magically, iPhone will even let you create a simulation of your own voice and have it speak for you, giving us all technology similar to what Stephen Hawking used, but in the palms of our hands.
What I think is most striking though is what all of these clever accessibility features mean for the rest of us, who may not need to use the features for their intended uses. The idea behind smart headsets — if they’re ever going to be truly useful — is that they will work almost as an extension of brains and bodies. We’ll want them to give us directions when we need them, and help us understand our surroundings. And we’ll need a way to interact with headsets without buttons or a touchscreen, using our voice or by gesturing with our hands.
This is for sure a tricky technical challenge, but it’s actually possible to imagine how such headsets might work, because these fundamental technologies already exist thanks to accessibility features on smartphones already on the market.
Ultimately, this is a great way to think about accessibility features and why they’re so important on our modern devices. Because they don’t just help the people who need them — they help make our technology even better for everyone else too.
1．How does the author prove the point in the second paragraph?| A．By giving examples. |
| B．By making a summary. |
| C．By giving definition. |
| D．By making a comparison. |
| A．To evaluate the uses of the phone. |
| B．To give instructions to the disabled. |
| C．To help users in solving various phones problems. |
| D．To make the world more accessible to the disabled. |
| A．Standard size. | B．Complex function. |
| C．Delicate design. | D．Convenient operation. |
| A．A new function of mobile phones. |
| B．A vital role of accessibility features. |
| C．A rapid change in life for the disabled. |
| D．A technical challenge of modern devices. |
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