NASA has discovered the eighth planet of a star system, similar to our solar system. The star, Kepler-90, is over 2,500 light years away and larger and
The Kepler-90 star system is much more compact (紧凑的) than our solar system. The outermost planet
The newly discovered planet, Kepler-90i, is
The discovery was made on data
2 . Studies of Mercury — the planet closest to the sun-show that it has shrunk by about 11 kilometers across since the solar system’s birth 4.5 billion years ago. As the planet cooled and contracted (收缩), its surface had many long curved ridges (山脊) similar to the wrinkles on a bad apple.
A new research on these ridges, called lobate scarps (瓣状陡坡), has found more of them, with steeper faces, than ever before. The discovery suggests that Mercury shrank by far more than the previous estimate, says Paul Byrne, a planetary scientist. The finding helps explain how Mercury’s huge metallic core (中心) cooled off over time. It may also finally settle the differences between theoretical scientists, who had predicted a lot of shrinkage, with observers who had not found evidence of that — until now. “We are resolving a four-decade-old argument here,” Byrne added.
Planetary scientists have been arguing over Mercury’s lobate scarps ever since the Mariner 10 spacecraft flew past the planet three times in 1974-1975. Researchers can use measurements of the length and height of the scarps to calculate how much planetary shrinkage they represent. That shrinkage is a product of Mercury’s strange structure — “like a core floating through space with a thin outer blanket,” says Byrne. Most of the planet is made of that large core, and so it would have cooled rapidly as heat rushed toward its surface.
The latest data, coming from NASA’s MESSENGER probe and covering the entire planet, showed many lobate scarps with sharp steeper faces, Byrne said. It also uncovered details on another kind of surface feature that may be related to shrinkage. These “wrinkle ridges” are less pronounced than the lobate scarps but may also have formed during contraction. Combined, the data on the lobate scarps and the wrinkle ridges suggest that Mercury’s diameter (直径) has shrunk by 11.4 kilometers, Byrne said.
1. How does the author explain the formation of the ridges on Mercury?| A．By making a comparison. | B．By providing some figures. |
| C．By describing the process. | D．By following the order of time. |
| A．It helps explain why Mercury has a huge metallic core. |
| B．It shows Mercury shrinks much less than previously thought. |
| C．It reveals there are less ridges on Mercury than people thought. |
| D．It helps settle the argument between theoretical scientists and observers. |
| A．It’s large core with thin surface. | B．The lobate scarps and wrinkles. |
| C．The pronounced wrinkle ridges. | D．The length and height of the scarps. |
| A．The latest data came from NASA’s Mariner 10 probe. |
| B．The lobate scarps may have formed before Mercury’s contraction. |
| C．The latest data provided supporting evidence of Mercury’s shrinkage. |
| D．The data suggests that Mercury’s diameter has shrunk to 11.4 kilometers. |
3 . A new study suggests that dark markings on the planet Mars represent sand — not water. The research in 2015 suggested that lines on some Martian hills were evidence of water. Yet American scientists now say these lines appear more like dry flows of sand. If water is present, it is likely to be a small amount. Water in liquid form would be necessary for microbial (微生物的) life.
NASA, the American space agency, said more research is needed. Michael Meyer is the lead scientist for NASA’s Mars exploration programme. He noted that the latest study does not reject the presence of water. But he admitted, “It just may not be as exciting as the idea of rivers going down the sides of cliffs (悬崖).”
The new findings come from a team led by Colin Dundas of the United States Geological Survey. His team measured 151 of these lines in 10 areas. Most of the lines end with slopes (倾斜) between 28 degrees and 35 degrees. These measurements are similar to active sand dunes (沙丘) on both Mars and Earth. A small covering of dust that moves and sometimes becomes lighter might help explain the markings. They usually appear in the Martian summertime, and then disappear until the next year. If these lines are dry, this suggests that recent Mars bas not had large amounts of liquid water. Dundas and his research team say that many questions remain.
“I still think that Mars has great potential for having had life early on in its history,” Meyer said. “As long as that’s true, we also have a reasonable possibility of life still being on Mars. It just happens to be cryptic or well hidden.”
NASA currently has no robotic — either on Mars or in development — with the ability to climb steep slopes. The lack of such equipment has engineers coming up with ideas like Martian helicopters or planes without pilots.
1. What do American scientists find on Mars now according to their study?| A．A lot of little life. | B．An amount of water. |
| C．Some Martian hills. | D．Dark markings are sand. |
| A．In Martian spring. | B．In Martian summer. |
| C．In Martian autumn. | D．In Martian winter. |
| A．Doubtful. | B．Trustful. | C．Unconcerned | D．Objective. |
| A．Undiscovered. | B．Strange. | C．Magical. | D．Icy. |
The U.S. space as agency NASA has released the first images captured by the James Webb Space Telescope, the most
One of the images shows some of the first galaxies (星系) ever to form, which means the Webb is seeing the galaxies that existed about 13 billion years ago. Additional
The Webb is the result of a $10 billion, 25-year project led by NASA and supported by other space agencies.
5 . 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. |
6 . Time has always been of great interest to scientist…
| Theory 1: According to Caltech cosmologist (宇宙学家) Dr Sean Carroll, the flow of time from past to future may be the symptom of our Universe having emerged from another universe that existed before the Big Bang and then gave birth to our own. Theory 2: In 1967, two American theorists came up with an equation describing the quantum (量子) state of the whole Universe. Known as the Wheeler-DeWitt equation, it includes many key features of the universe, such as its size. But one aspect is absent: time. Some theorists believe this implies that time only exists in our minds. Theory 3: According to theorist Prof Lee Smolin at the Perimeter Institute, Canada, the existence of life in the Universe is the result of the laws of physics evolving to their current state over an unlimited number of previous universes. If true, this means that our very existence is proof that time does exist. Theory 4: In 2009, physicists at the universities of Bristol and Cambridge showed that the passing of time revealed by, say, the cooling of a cup of tea, may be due to quantum effect called ‘entanglement’. This involves the particles (粒子) in the team interacting with their surroundings, being bound together and becoming harder to distinguish from each other—a one-way process that requires the forward progression of time to occur. Theory 5: Dark energy, the mysterious anti-gravitational force that drives the expansion of the Universe, may be linked to the existence of the arrow of time. Last year, two cosmologists at the Yerevan Physics Institute showed that dark energy leads to the growth of entropy, a measure of disorder, in the Universe. |  |
| A．time is flexible | B．time is constant |
| C．time does go forth and back | D．time does exist in some way |
| A．Theory 1. | B．Theory 2. |
| C．Theory 3. | D．Theory 4. |
| A．It leads to the existence of multi-universities. |
| B．It is what keeps the universe in order. |
| C．It increases in strength with gravity. |
| D．It is what makes the universe get bigger. |
7 . A lunar rover(月球车) has spotted a strange cube-shaped object and will change its official course to check it out, needing 2-3 months to arrive. Official observations suggest it could be a rock pushed upward from the impact(撞击) of an outside object that clearly landed next to it, or a technological relic from previous exploration, or hopefully, perhaps something that can’t be explained.
The Chinese Yutu 2 lunar rover spotted it in its cameras while passing a C-shaped enclosure on the moon’s far side. “Under the dark and deep sky, a circle of winding mountains stood on the extension line of the sky and the moon. On the side, people can’t help but admire the extraordinary work of the universe.” wrote Our Space, a Chinese -language blog connected with the national space agency. The drivers zoomed in(镜头拉近) on the pictures, slowly admiring them one by one. Suddenly, a cube on the northern skyline attracted their attention. The object looked like a “mysterious hut(小屋)”.
Right angles are unusual in nature, usually marking out something artificial if we see them through the faint light of a forest. On the moon, however, there’s not a lot of room for possibilities for a cube. After some days, the camera produced an image to share with the world of their “mysterious hut(小屋)”. The blog post suggested it could be evidence of previous moon missions, but noted the presence of a small impact crater(陨石坑) next to the cube, which could have led to the rising of rocks.
Popular Science magazine said the image could simply be pixelated, as it was taken from far away, Yutu2 landed with Chang’e 4, the first two spacecraft ever to land on the moon’s far side. They’ve in fact had the place to themselves since they arrived in 2019.
1. What can we learn about the cube from the first paragraph?| A．It will change its course soon. |
| B．It has been identified to be a rock. |
| C．It will be better observed after 2-3 months. |
| D．It’s identity is a mystery forever. |
| A．What people think of the cube. |
| B．What the cube was like when spotted. |
| C．How the cube was found. |
| D．How beautiful the universe is. |
| A．Clear | B．Unclear | C．Interesting | D．Unique. |
| A．A lunar rover sent by China 3 months ago. |
| B．The environment on the moon. |
| C．An impact crater on the moon. |
| D．A cube object spotted by China’s lunar rover on the moon. |
8 . An international team of scientists says it has discovered two new “super-Earth” type planets about 100 light-years away, one of which may be suitable for life. Unlike any of the planets in our solar system, the two newly-discovered super-Earths are larger than Earth, but lighter than icy planets like Uranus and Neptune.
Researchers at Belgium’s University of Liège announced that they found another one while using Earth-based telescopes to confirm the existence of a different planet initially discovered by a NASA satellite in the same solar system.
NASA’s satellite found planet LP 890-9b, which is about 30% larger than Earth and orbits its sun, LP 890-9, in just 2.7 days. ULiège researchers used their telescopes in Chile and Spain to take a closer look at the planet with high-precision cameras. That’s when the scientists discovered another planet, LP 890-9c, which is 40% larger than Earth and takes 8.5 days to orbit its sun.
Francisco Pozuelos, a researcher at the Institute of Astrophysics of Andalusia, said that the planet could be suitable to life despite being a mere 3.7 million miles from its sun. Earth, by comparison, is located over 93 million miles away from our sun. “Although this planet orbits very close to its star, the amount of stellar irradiation (恒星辐射量) it receives is still low, and could allow the presence of liquid water on the planet’s surface, so long as it has a sufficient atmosphere,” Pozuelos said. That’s because although LP 890-9 is by far larger than its planets, it is about 6.5 times smaller than our sun and is roughly half as cool temperature-wise as our sun, he added. “This explains why LP 890-9c, despite being much closer to its star than the Earth is to the Sun, could still have conditions that are suitable for life,” said Pozuelos.
1. Which of the following is the smallest?| A．LP 890-9. | B．The Earth. | C．LP 890-9b. | D．LP 890-9c. |
| A．By analyzing its mass and orbit. |
| B．By comparing it with LP 890-9b. |
| C．By using ground-based telescopes. |
| D．By taking photos from a NASA satellite. |
| A．Different opinions about the new planet. |
| B．Scientists’ future plan about the new planet. |
| C．Reasons for the new planet being suitable to live on. |
| D．Comparisons between the planet and our Earth. |
| A．Two Newly-discovered Super-Earths |
| B．Looking for Life Existing in Outer Space |
| C．Great Breakthroughs Made by Scientists |
| D．LP 890-9c, the Future Substitute of Our Earth |
9 . “Pale moon rains. Red moon blows. White moon neither rains nor snows.” For generations, people have watched the moon for signs of changes in the weather. The moon does, in fact, affect the Earth’s climate and weather patterns in several unnoticeable ways.
The most obvious effect the moon has on the Earth can be seen in the ocean tides (潮汐). A world without tides would have very different weather systems. Tides are one factor that influences the movement of ocean currents, which move warm or cool water about the Earth. Warm ocean currents bring warmer wetter weather, while cold ocean currents bring colder drier weather.
While the lunar nodal cycle is set to bring marked change over the coming decades, the moon affects the Earth in a few other little-known ways on a shorter timescale.
The moon is also thought to affect polar temperatures and contribute to fluctuations (波动) in the extent of Arctic ice. Satellite measurements have shown that the poles are 0.55℃ warmer during a full moon. In addition, tidal forces act to break up ice sheets and change ocean heat flows, converting the amount of ice in the Arctic Ocean.
The moon’s influence, sometimes unnoticeable and sometimes strong, has had a formative impact on life on Earth. Some scientists argue that it is the moon that made life possible in the first place. The moon steadies the Earth as it spins on its axis (轴), helping to give us a stable climate. Without it, the Earth would rock more irregularly. The poles would move obviously in relation to the Earth’s orbit. Seasons, days and nights would all look very different. The moon is closest to the Earth in the universe, without which the Earth would be a very lonely place.
1. What is the author’s purpose of writing paragraph 1?| A．To draw people’s attention to the text. | B．To teach people signs of weather changes. |
| C．To show people how to appreciate the moon. | D．To tell people to prepare for extreme weather. |
| A．The world weather system. | B．The impact of ocean tides. |
| C．The movement of ocean tides. | D．The reasons for warmer weather. |
| A．Changing. | B．Speeding. | C．Determining. | D．Keeping. |
| A．Health. | B．Entertainment. | C．Science. | D．Sports. |
10 . It’s more than 384,000km from Earth. We can see it most nights. And it’s not made of cheese! I am, of course, talking about the Moon. Astronauts have taken giant steps to explore this natural satellite floating in space, but despite it being out of reach for most of us,
The Moon, obviously, provides moonlight. A full moon, seen roughly once a month, can light up our way on an otherwise dark night. But while this lunar light can be impressive to look at,
The Moon might affect our behaviour too. Writing about this for BBC Future, Claudia Hammond explains one interesting theory. Just as the Moon’s gravitational pull affects the tides, it exerts its influence on the water in our bodies. But she points out “the Moon is smaller than the Earth, so its gravitational pull is correspondingly less powerful. What’s more, it exerts the same force on us regardless of whether it’s new or full.”
| A．it can affect our sleeping patterns |
| B．it still moves us in mysterious ways |
| C．great achievements have been made by us |
| D．There are many theories about how the Moon can affect other things too |
| E．Even winemakers look to the Moon when planting and pruning grapevines |
| F．Research into ancient myths about the effects of the lunar cycle on us is ongoing |
| G．Scientists attach great significance to space exploration about the lunar cycle on us |
