1 . Fans of Star Wars might remember Luke Skywalker’s home planet. Called Tatooine, the planet orbits two stars. A new study suggests similar planets might be the best focus in the search for places that can host life outside our solar system.
Many suns come in pairs called binary stars. Lots of these should have planets orbiting them. That means there could be more planets orbiting around binary stars than around lone stars like our sun. But until now, no one had a clear idea about whether those planets could host life. New computer models suggest that in many cases planets like Tatooine could be fit for life.
The researchers ran computer models of binary stars arranged in thousands of ways. Each had an Earthlike planet orbiting the two stars. The team modeled different sizes and shapes of the stars’ orbit around each other. They then tracked the movement of the planets for up to a billion years of simulated (模拟) time. That showed whether the planets would stay in orbit over timescales that might develop conditions to start life. They also checked to see if the planets stayed in a habitable zone. That’s the region around a star where an orbiting planet’s temperatures are never extremely hot or cold, and water could stay liquid (液态).
“An atmosphere and oceans could make a great difference,” says Mariah MacDonald, who took part in the new modeling work. Plentiful air and water could change the picture. Adding atmospheres to the modeled planets should increase the number of stars that could host life. She hopes to build more advanced models in coming months.
“Models of planets orbiting binary stars could guide future efforts to look for them with telescopes,” says Jason Wright, who studies the physics of stars at Pennsylvania State University. “This is an under-explored population of planets. There’s no reason why we can’t go after them,” he says. “And it might be worthwhile to try.”
1. Why does the author mention Tatooine in Star Wars?| A．To attract movie lovers. | B．To introduce the topic. |
| C．To remember an old friend. | D．To present a newfound planet. |
| A．Its preparation. | B．Its application. | C．Its process. | D．Its finding. |
| A．Improve the study. | B．Lead a peaceful life. |
| C．Start another project. | D．Travel into outer space. |
| A．Doubtful. | B．Positive. | C．Concerned. | D．Uncaring. |
2 . “Palace, Mountain, Moon?” has been selected by NASA as the Astronomical Picture of the Day for December 25, 2023.
The photo was taken by Valerio, a young photographer of Turin, Italy. It was shot on the evening of December 15, 2023. While he knew about NASA’s competition, he hadn’t considered participating until receiving much encouragement from his social media followers. Soon after, he received the message, “Your image has been chosen as the astronomical photo of the day.” It was incredible!
In a photo like this, nothing is left to luck. The concept came to him back in 2017. Walking on the hills north of Turin, he found several spots perfect for including both the Basilica of Superga Palace and Mountain Monviso. After numerous visits over several months, he identified four spots where Superga and Monviso line up just right.
After pinpointing these locations, he experimented with shooting them at different times. “I knew I needed something special to perfect the photo. The Sun was a no-go, so I turned to the Moon. Its various phases and position s reach an azimuth angle (方位角) of 230 degrees,” Valerio said. With this in mind, he researched the Moon’s phases, marked potential dates on the calendar, and planned the exact moments when the moon could join the queue.
It was very successful, especially because the Moon was in a waxing phase. This meant that in the photo, not only was its crescent (新月) lit up, but so was the left part, its shadowed side. That part is lit by reflected light, also known as Da Vinci’s glow, named after him because he was the one who theorized about why the Moon’s shadowed side is brightened. During the early days of the waxing Moon phases, the shadowed part is visible because the Sun’s light reflects off the Earth and hits the Moon’s shadowed side, giving it a greyish, silvery color. This allowed the light to outline Monviso on the left as well.
1. Why did Valerio send the photo to NASA?| A．He took an interest in astronomical advances. |
| B．He expected to create an impact on social media. |
| C．He received broad support from enthusiastic fans. |
| D．He wished to make his hometown a tourist hot spot. |
| A．shine light on each other | B．stand in a straight line |
| C．fit each other in size | D．vary from usual in color |
| A．Studying how the Moon phase changes. | B．Calculating the Superga-Monviso distance. |
| C．Analyzing when to adjust the camera angle. | D．Measuring the height of the observation point. |
| A．The outline of the crescent. | B．The outline of Superga. |
| C．The dark side of the Moon. | D．The shadowed side of the Earth. |
3 . I was 10 when I saw my first total solar eclipse (日食). It was 1979 and we were staying in Canada, where my dad worked for a time as a welder (焊工). He was a great science enthusiast and had been talking about this eclipse for what seemed like years. He just didn’t tell me and my brother that we would have to get up at daybreak and head out into the freezing February weather to experience this event.
Dad told us we were lucky even to be near the path of totality, and noted that unless we were prepared to travel extensively, our next chance to see a total solar eclipse likely wouldn’t happen until the 21st century. So, we rode in moody silence out to some field where loads of other people were wandering about, waiting in the cold for their moment in the sun’s absence.
My brother complained that we wouldn’t really be able to look at the eclipse without being blinded. But my dad, who generally thought of everything, produced two awkward welding masks (面罩), which he fitted to our heads. The masks preserved our eyesight, and also quietened our grousing. It’s hard to know which feature of the masks my dad appreciated more.
Soon, it didn’t matter. The moon passed between us and the sun. The lights of the world dimmed, then went dark. There was a collective “Oooooh!” from the crowd. Some people even screamed. My brother simply said, “Whoa.” And he spoke for all of us down through the ages who have been struck by the awe and wonder of a total solar eclipse. You can read more about humanity’s encounters with some of the great eclipses in history with our story on page 40.
My dad did not live to see another eclipse, but he’ll be with me in spirit when I view the next one this April, right around the time you’re reading this. I hope you get to see it, too.
Stephen C. George, Editorial Director
Feel free to send comments and questions to editorial@discovermagazine.com.
1. How did the author probably feel about watching the eclipse at first?| A．Unwilling. | B．Enthusiastic. | C．Worried. | D．Nervous. |
| A．Fear. | B．Doubts. | C．Complaining. | D．Screaming. |
| A．By using the setting. | B．By adding sensory details. |
| C．By stating a point of view. | D．By drawing a comparison. |
| A．A blog. | B．An editor’s note. | C．A travel journal. . | D．A report. |
4 . For future humans to survive long periods on Mars, growing food on the planet is a must. It would be too costly and risky to rely upon rocket deliveries to meet the food needs of settlers. With this in mind, scientists are exploring ways to improve space farming.
Researchers work in a controlled greenhouse. They have identified a way that could improve crop production in simulated (模拟的) Martian soil, with different crops grown together. The method is called “intercropping”, invented by ancient Maya farmers in what is now Central America.
In their experiments, the researchers grew cherry tomatoes, peas and carrots together in small, round containers. Tomatoes grown in this way produced about double the amount of tomatoes grown alone—or “monocropped”—in the same simulated Martian soil. The tomatoes were also bigger. They flowered and matured earlier, gave more fruit per plant and had thicker stems. The amounts of peas and carrots did not increase with intercropping.
Rebeca Goncalves, an astrobiologist and lead writer of the study, said the research is the first time the intercropping technique was used in space soil, and that it was a big find—one that they could now build further research on. The crops were grown in simulated Martian regolith, a soil with no organic matter —a near-perfect physical and chemical match to real Martian soil.
The researchers added useful bacteria and nutrients. They also controlled the gases, temperature and humidity inside the greenhouse to match conditions expected in a Martian greenhouse. Intercropping involves growing plants with properties that could help each other grow. The method makes the best use of resources including water and nutrients.
The researchers said the tomato plants in intercropping may have benefited from being close to the pea plants. That is because the peas are good at turning nitrogen from the air, with the help of bacteria introduced into the soil, into an important nutrient. Overall, the tomatoes, peas and carrots grew well, though not as well as in Earth soil in the same greenhouse.
1. What is the benefit of intercropping mentioned in the article?| A．Increasing crop yield. | B．Preventing soil pollution. |
| C．Decreasing sunlight exposure. | D．Reducing water consumption. |
| A．Enhancing growth of carrots. |
| B．Increasing fruit production in tomatoes. |
| C．Transforming nitrogen into a crucial nutrient. |
| D．Improving the variety of bacteria introduced into the soil. |
| A．Carrots benefited the most from intercropping. |
| B．The crops grew as well as they would in Earth soil. |
| C．The presence of peas helped tomatoes produce more fruit. |
| D．Peas and carrots showed significant growth improvement in intercropping. |
| A．Intercropping is developed for growing crops in space. |
| B．The study found Intercropping resulted in higher tomato yields. |
| C．Scientists are struggling to find ways to improve crop production in space. |
| D．Researchers successfully grew some plants in imitated Martian soil using intercropping. |
An international team of astronomers used a database combining observations from the best telescopes in the world
The Milky Way Galaxy
To test this theory, astronomers look at distant galaxies. Due to the limited speed of light, it takes time for light to travel across the void of space. The light we saw last night from an object 10 billion light years away
1. When will the solar eclipse happen?
| A．At 2:50 pm. | B．At 3:20 pm. | C．At 3:10 pm. |
| A．To keep the birds safe. | B．To stop the birds singing. | C．To protect her eyes. |
7 . A high school teacher and his students have discovered that an asteroid (小行星) hit by a NASA spacecraft, in a test run for saving the Earth from an impact, is behaving unexpectedly. The find could have effects on future planetary defense missions.
The Double Asteroid Redirection Test (DART) is a project designed to launch and crash a fridge-sized spacecraft into an asteroid called Dimorphos, orbiting a larger asteroid Didymos. The purpose of the exercise was to see how significantly the previous path of Dimorphos could be changed by the impact. Before DART’s impact, it would take Dimorphos 11 hours and 55 minutes to complete a lap around Didymos. NASA was hoping the DART crash could change the cycle by about 73 seconds, but observations made in the weeks following the impact determined that the results were much more significant, reducing Dimorphos’ orbital period by some 33 minutes.
But California high school teacher Jonathan Swift and his students discovered that Dimorphos’ orbital period was a full minute longer than the time reported by NASA last year. They used the school’s observatory to track Dimorphos and Didymos for several months last fall. Swift presented his class’ findings at the American Astronomical Society conference in June. The DART team has since confirmed that Dimorphos did indeed continue slowing in its orbit up to a month after the impact.
Scientists aren’t sure exactly what is behind the slowdown of Dimorphos. But recent observations of the asteroid have revealed a vast field of large rocks were kicked up by the impact. It’s possible that some of the larger space rocks fell back onto Dimorphos within that first month, slowing its orbit further, DART team member Harrison Agrusa said.
The DART team plans to release its own report on the unexpected findings in the coming weeks. However, complete answers may have to wait until 2026, when the European Space Ageney’s Hera spacecraft is scheduled to investigate the crash site up closely.
1. What was the purpose of launching the NASA spacecraft?| A．To change Dimorphos’ orbital cycle. |
| B．To stop Dimorphos hitting the Earth. |
| C．To reduce Didymos’ path around the sun. |
| D．To make Didymos move in a bigger orbit. |
| A．1 full minute. | B．2 minutes or so. |
| C．Nearly 33 minutes. | D．About 32 minutes. |
| A．How seriously Dimorphos was damaged. |
| B．What happened to the rocks on Dimorphos. |
| C．Why Dimorphos slowed down for a month. |
| D．What Dimorphos looked like after the impact. |
| A．To crash into another asteroid nearby. |
| B．To measure the previous impact results. |
| C．To affect the motion of the twin asteroids. |
| D．To identify the asteroids threatening the Earth. |
8 . What would happen to you if you fell into a black hole? Some physicists believe you would burn up the moment you entered one. Einstein’s general theory of relativity predicts that you would pass through, unaware that you were lost to the rest of the universe.
Black holes have a bottom, but you wouldn’t live to see it. Gravity, as you fell, would grow stronger. The pull on your feet, if you were falling feet first, would be so much greater than the pull on your head that you would be stretched until you were torn apart. But pieces of you would reach the bottom. From there, some physicists believe that those pieces that once were you could end up in another universe.
However, nobody has ever seen or will see a black hole. A black hole is invisible, a blank spot in space, but scientists are able to know its existence by the effect it has on things around it. For example, if an object comes close to a black hole, it should be possible to see the powerful gravity of the black hole trying to pull the object in. In fact, this is exactly what scientists are planning to do: to observe one while it eats a very large object.
The black hole at the center of the Milky Way galaxy is peaceful but is currently pulling a gas cloud toward itself fast. As the gas cloud begins to enter the black hole, telescopes will be able to take a picture of a black hole in action. This will be the best proof so far that black holes certainly exist.
A black hole is an eater. The nearer objects get to it, the hotter they become. Black holes also spin (旋转), and the extreme heat and spinning break up and expel large amounts of matter at extremely high temperatures. This heated matter flies through space, away from the hole at unbelievable speed. It can travel millions of light-years straight through a galaxy. The material then cools, comes together, and eventually forms new stars around the galaxy, thus the birth of new universes.
1. According to paragraph 2, what is the consequence of falling into a black hole?| A．Being reduced to pieces. | B．Being stretched into a single piece. |
| C．Being burned in another universe. | D．Being pulled to the bottom instantly. |
| A．To prove that no one can see a black hole. |
| B．To show that black holes can in fact be detected. |
| C．To observe while a black hole eats a huge object. |
| D．To see the powerful gravity a black hole possesses. |
| A．Set up. | B．Take in. | C．Throw off. | D．Call for. |
| A．What a black hole is and its various aspects. |
| B．Why a black hole is invisible and its final discovery. |
| C．How a black hole is formed and its unknown mysteries. |
| D．When a black hole bears a universe and its amazing origin. |
9 . Astronomers have examined the stars that a new space telescope might target, to prepare for one of the most advanced searches for life on other planets. They found out which star systems might be more suitable to hunt for potential life.
In the 2040s, NASA plans to launch the Habitable Worlds Observatory(HWO). Its big goal is to image about 25 Earth-like planets in the habitable zones of sun-like stars-where water and even life could exist. Before building the HWO, scientists are working on significant challenges it will face.
One of those is choosing stars within around 100 light years from Earth that the telescope might target. Caleb Harada at the University of California, Berkeley, and his team analyzed 164 potential stars to determine their characteristics. These stars could become some of the most studied stars ever.
Harada and his team discovered that 102 of the stars are binaries(双子星), which could make the search for life more complex. The HWO telescope will use a tool to block out the stars’ light to attempt to image planets in orbit and study the gases in their atmospheres. “If binaries are too close together, the light from the unblocked star will be so bright that it’ll cover up the planets and make them hard to see,” explains Bruce Macintosh from the University of California Observatories.
Out of all the stars, 33 have dust rings that could make it hard to see planets clearly. “This makes exploring harder,” says Harada. “Some stars also sometimes burst into bright flames, like our sun’s flares, which aren’t always deadly. But we need to check closely that they’re not too strong, because these can affect life and living conditions,” explains Harada.
1. Why is HWO to be built?| A．To take pictures of planets. | B．To find out habitable planets. |
| C．To identify Earth-like planets. | D．To prepare for the search for life. |
| A．The application of the telescope. | B．The characteristics of studied stars. |
| C．The analysis of potential sun-like stars. | D．The challenge of finding the right stars. |
| A．The HWO telescope. | B．Tightly spaced binary stars. |
| C．The brightness of unblocked stars. | D．The gases in planets’ atmospheres. |
| A．Space exploration. | B．Stars’ intense bursts. |
| C．Frequent solar flares. | D．Dust rings on planets. |
A new study suggests Jupiter’s icy moon (卫星) Europa produces much less oxygen than previously thought. The study was based on the data
The study involved Juno’s instruments measuring levels of oxygen
However, the space agency noted those estimates of oxygen were much less than those measured in earlier studies about the moon. Europa is a little
Since Europa was believed to have a large ocean under its surface,
