1 . With the fast development of astronomy, astronomers are eager to find a hint of the familiar: planets that resemble Earth. By pushing technology to the limits, astronomers are rapidly approaching the day when they can find another Earth.
The most direct approach is to take a picture of it with a telescope. However, a more effective way is to use “the Doppler technique”. This involves analyzing starlight for evidence that the star’s movement is affected by the gravitational pull of a planet. Nowadays, astronomers can tell when a planet is pulling its star by only one meter a second — about human walking speed. That’s enough to detect a giant planet in a big orbit, or a small planet if it’s close to its star.
Another approach is to watch a star for a slight dip in its brightness. This occurs when an orbiting planet passes in front of the star and blocks part of its light. At most, a tenth of all planetary systems are oriented so that these mini-eclipses (日食,月食) — called transits (凌日) — are visible from Earth. So, astronomers have to monitor a lot of stars to capture just a few transits.
The dream of astronomers is to discover a rocky planet roughly the size of Earth orbiting in a habitable zone, one that is neither too hot nor too cold to support life. If they succeed, they will have found what biologists believe could be a promising residence for life.
The best places to look may be dwarf stars. Smaller than the sun, dwarf stars are plentiful; seven of the ten stars nearest to Earth are dwarf stars. They also provide a steady supply of sunlight to any life-bearing planets within their habitable zone. Additionally, dwarf stars are dim, so the habitable zone lies closer in. If the planet is closer to the star, it’s easier for astronomers to detect a transit observation. A close-in planet also has a stronger pull on its star. That makes it easier to detect with the Doppler method.
1. According to paragraph two, astronomers analyze starlight with the aim of finding ________.A.where we can detect a giant orbit |
B.why a small planet is close to its stars |
C.whether the motion of the stars is changed |
D.how strong the power of the gravitational pull is |
A.Transits last a very short period of time. |
B.Most planetary systems don’t have transits. |
C.Transits only occur for a small number of stars. |
D.No more than 10% planetary systems have visible transits from Earth. |
A.dwarf stars are limited in number |
B.their planets are close to the Earth |
C.the closeness of the habitable zone to dwarf stars aids detection |
D.the brightness of dwarf stars to Earth improves their visibility |
A.Confident. | B.Suspicious. | C.Ambiguous. | D.Unconcerned. |
2 . 听下面一段较长对话,回答以下小题。
1.A.The possible existence of life on other planets. |
B.Methods for building powerful new telescopes. |
C.A technical problem that astronomers can’t solve |
D.The discovery of planets orbiting distant stars. |
A.They studied variations in the appearance of the parent stars. |
B.They were able to see the planets with a telescope. |
C.They compared the parent stars to the Sun. |
D.They sent astronauts on a mission into space |
A.Their surface features. | B.Their chemical composition. |
C.Their temperature. | D.Their age. |
A.All the stars are orbited by their own planets. |
B.We currently have a telescope that can be used to see other planets |
C.By a very direct method, the astronomers measured subtle distortions. |
D.By a very indirect method, the astronomers measured subtle distortions. |
3 . 阅读下面短文,在空白处填入1个适当的单词或括号内单词的正确形式。
The Voyager Program was conceived as a grand tour of the solar system. It was actually
The fly-by trips
4 . Two powerful NASA telescopes have detected the oldest and most distant black hole ever found. Data collected via energetic X-rays by the Chandra X-ray Observatory and James Webb Space Telescope has helped astronomers spot the signature of a growing black hole within the early universe just 470 million years after the big bang, which occurred 13.8 billion years ago. The discovery, described in a study published in Nature Astronomy, may help astronomers figure out how some of the first supermassive black holes formed in the universe.
“We needed Webb to find this remarkably distant galaxy (星系) and Chandra to find its supermassive black hole, “ said lead study author Akos Bogdan, in a statement. ”We also took advantage of a cosmic magnifying glass (宇宙放大镜) that boosted the amount of light we detected. “ He was referring to an effect called gravitational lensing (引力透镜效应), which occurs when closer objects act like a magnifying glass for distant objects. Gravity essentially twists and strengthens the light of distant galaxies in the background of whatever is doing the magnifying, enabling observations of otherwise invisible features.
Astronomers detected the black hole in a galaxy called UHZ1. At first glance, the galaxy appeared in the same direction as a cluster of galaxies known as Abell 2744, which is located about 3. 5 billion light-years from Earth. But data collected by the Webb telescope showed that UHZl is actually much farther away and located beyond the cluster at 13. 2 billion light-years from Earth.
The team used the Chandra Observatory to detect superheated gas releasing X-rays within UHZ1, the obvious sign of a supermassive black hole growing in size. The detection was made possible by the Abell cluster of galaxies, which intensified the light of the UHZ1 galaxy and the X-rays released by the black hole by a factor of four.
Astronomers think the discovery will help them better understand how supermassive black holes appeared and reached their huge masses so soon after the beginning of the universe.
1. What’s the possible age of the newly-found black hole?A.470 million years. | B.13.33 billion years. |
C.13. 8 billion years. | D.14. 27 billion years. |
A.The process of the research. |
B.The significance of the discovery. |
C.The contributors to the discovery. |
D.The background of the research. |
A. | B. |
C. | D. |
A.The Oldest and Most Distant Black Hole Spotted. |
B.Two Powerful NASA Telescopes Coming into Service. |
C.New Supporting Evidence of the Big Bang Theory Detected. |
D.Astronomers Figuring Out How the First Black Holes Formed. |
5 . If you live on this planet, there’s a decent chance you’ve seen the classic Star TrekEpisode, in which captain Kirk and several members find themselves in what appears to be another universe.
These days, it seems the idea of the multiverse—many worlds—is having its Hollywood moment. Its appeal as a storytelling device is obvious—characters explore a multi-world with varying degrees of similarity to our own, as well as different versions of themselves. Hence, it has been fully established in mainstream pop culture.
While Hollywood can’t seem to get enough of the multiverse, it remains deeply controversial (有争议的) among scientists. Advocates on the two sides show no mercy toward each other in their books, on their blogs. But physicists didn’t pull the idea out of thin air—rather, several distinct lines of reasoning seem to point to the multiverse’s existence. However, critics warn that making the multiverse legal could make it harder for the public to distinguish speculative (推测性的) theories from established fact, making it more difficult to keep pseudo-science (伪科学) at bay. Giving credit to such speculation risks “turning fundamental physics into pseudo-science”.
The multiverse controversy is rooted in the idea of test ability. If we can’t interact with these other universes, or detect them in any way, some experts insist that reduces them to mere philosophical speculation. But Carroll, an advocate for “many worlds”, argues that mathematics is the language describing our physical theories. Since Schrdinger’s equation (方程), on which Quanturr (量子) mechanic rests, predicts the existence of many worlds, so be it.
Could a more expansive view of the universe itself be the next breakthrough? As Siegfried puts it: “Every time in the past that we’ve thought, ‘We’ve got it; this is what the whole universe is’—the people who’ve said, ‘Maybe there’s more than one of those’ have always turned out to be right.”
1. Why is Hollywood so occupied with the multiverse?A.It makes for engaging plots. |
B.It is a much-talked-about topic. |
C.It is helpful to popularize science. |
D.It dominates the mainstream pop culture. |
A.Out of date. | B.Out of place. | C.Out of nowhere. | D.Out of question. |
A.it can be detected somehow |
B.it can be reasoned logically |
C.it can be interpreted philosophically |
D.it can be predicted by mathematics equation |
A.Doubtful. | B.Dismissive. | C.Unclear. | D.Approving. |
6 . A satellite is an object in space that orbits around another. It has two kinds — natural satellites and artificial satellites. The moon is a natural satellite that moves around the earth while artificial satellites are those made by man.
Despite their widespread impact on daily life, artificial satellites mainly depend on different complicated makeups. On the outside, they may look like a wheel, equipped with solar panels or sails. Inside, the satellites contain mission-specific scientific instruments, which include whatever tools the satellites need to perform their work. Among them, high-resolution cameras and communication electronics are typical ones. Besides, the part that carries the load and holds all the parts together is called the bus.
Artificial satellites operate in a systematic way just like humans. Computers function as the satellite’s brain, which receive information, interpret it, and send messages back to the earth. Advanced digital cameras serve as the satellite’s eyes. Sensors are other important parts that not only recognize light, heat, and gases, but also record changes in what is being observed. Radios on the satellite send information back to the earth. Solar panels provide electrical power for the computers and other equipment, as well as the power to move the satellite forward.
Artificial satellites use gravity to stay in their orbits. Earth’s gravity pulls everything toward the center of the planet. To stay in the earth’s orbit, the speed of a satellite must adjust to the tiniest changes in the pull of gravity. The satellite’s speed works against earth’s gravity just enough so that it doesn’t go speeding into space or falling back to the earth.
Rockets carry satellites to different types and heights of orbits, based on the tasks they need to perform. Satellites closer to the earth are in low-earth orbit, which can be 200-500 miles high. The closer to the earth, the stronger the gravity is. Therefore, these satellites must travel at about 17,000 miles per hour to keep from falling back to the earth, while higher-orbiting satellites can travel more slowly.
1. What is Paragraph 2 of the text mainly about?A.The appearance of artificial satellites. | B.The components of artificial satellites. |
C.The basic function of artificial satellites. | D.The specific mission of artificial satellites. |
A.Providing electrical power. | B.Recording changes observed. |
C.Monitoring space environment. | D.Processing information received. |
A.By relying on powerful rockets to get out of gravity. |
B.By orbiting at a fixed speed regardless of gravity’s pull. |
C.By changing speed constantly based on the pull of gravity. |
D.By resisting the pull of gravity with advanced technologies. |
A.They are more affected by earth’s gravity. |
B.They take advantage of rockets more effectively. |
C.They have weaker pull of gravity in higher orbits. |
D.They are equipped with more advanced instruments. |
7 . Mars is no stranger to life. Seven U. S. spacecraft have successfully landed there, and all of them took microbes to the planet’s surface(though the bugs probably did not survive for long). Yet the world’s space agencies continue to maintain strict spacecraft sterilization (消毒) procedures in the hope of minimizing the spread of Earth life beyond our planet. For decades this idea — known as planetary protection—is widespread. Now, some scientists say, these procedures are preventing the search for life beyond Earth by raising costs and preventing innovative missions-without meaningful benefits.
Of all missions to Mars to date, only the Vikings, the first trip to the Red Planet, were intended to test for life. Spacecraft that went later did not have that ability. But a future mission will, and the protectionist thinking goes, a spacecraft might not be able to distinguish between a life form native to Mars and one with origins on Earth. In July 2013 astrobiologists Dirk Schulze-Makuch and Alberto Fairen argued against this in Nature Geoscience.
“If Earth life can thrive on Mars, they almost certainly already do,” the authors write. “If they cannot, the transfer of Earth life to Mars should be of no concern, as it would simply not survive.”
With clear evidence of a water y history and some signs of water present, Mars could be where we find life in our solar system. And with the development of Curiosity’s precise landing system, we can finally reach the mysterious parts of the planet. But it’s these areas that require a craft sterilization process.
In the 1970s Vikings 1 and 2 revealed what seemed like a dead planet, so planetary-protection requirements were relaxed. Now, with more knowledge of Mars’ environment, missions set to visit areas with evidence of flowing water below the surface have to meet the strict-and more costly- Vikings standards.
Finally, there’s the philosophical problem of what responsibility, if any, we have to other planets and any life we leave there. The truth is we’re never going to be able to fully protect Mars if we intend to explore it. And spreading is simply what life does.
“If we want to survive for a long time, we have to expand beyond Earth,” Schulze-Makuch says. “There’s no other way.”
1. Strict spacecraft sterilization procedures are meant to ______.A.decrease the costs of space exploration |
B.help the search for life forms beyond Earth |
C.contribute to innovative missions in the universe |
D.prevent Earth life being transferred to other planets |
A.there was no preclse landing system |
B.Mars was considered to be a lifeless planet |
C.the mysterious parts of Mars remained unknown |
D.flowing water was found below the surface of Mars |
A.Mars is now on the edge of being destroyed |
B.human beings are too ambitious to expand beyond Earth |
C.there is no need to worry about bringing Earth life to Mars |
D.we need to be responsible for keeping Mars what it is like now |
A.optimistic | B.relaxed | C.debatable | D.negative |
8 . For those of us who grew up watching Star Trek, exploring space has been about discovering strange new worlds. And there are plenty of worlds to explore in time, but we still need major technological advancements to reach planets that are light years away.
What we are doing in space today is providing unbelievable benefits right now, right here on Earth. From space, we can monitor, manage and care for our planet. Satellite-based sensors show us the short- and long-term effects of human activity on our environment. Many companies are using their interest in space to help solve problems here, from using hyperspectral imaging(高光谱成像), which enable us to map vegetation(植被) and rain forests, to microsatellites that provide global connectivity for the network of things.
My company, OneWeb, is focusing on what I believe is one of the world’s most important issues: the need for equal access to the Internet. The Internet has become our economic lifeblood. And yet, nearly half of the world’s population doesn’t have Internet access. Space is playing a key role in bridging this digital divide. OneWeb is launching 1,980 satellites to help bring Internet access to people everywhere, and our first production satellites are already flying in space and have shown very high download speeds.
Fiber and cable Internet access technologies already cover most financially viable(可行的) major cities. Similarly, these regions will also be the first to be served with 5G. Poor communities are the last to get connected, and without connectivity, those communities have no chance to lift themselves from poverty. OneWeb’s satellites will reach every community in the world and enable equal access to the Internet for the world’s less developed places.
Fifty years from the day when man first walked on the moon, we are still only approaching the possible. There will be tens of thousands of new satellites, space stations and factories in the coming years to bring advancements in communications, scientific research, monitoring the earth, exploring space and more. This is exciting, but we must take action carefully.
1. What is the second paragraph mainly about?A.Benefits space exploration can bring to us. |
B.Problems space exploration leads to. |
C.Steps of space exploration requires. |
D.Equipment space exploration needs. |
A.Increase download speeds. |
B.Narrow the gap in Internet learning. |
C.Help people set up and maintain a website. |
D.Enable people to make use of the Internet equally. |
A.More than six decades ago, man first walked on the moon. |
B.More than half of the world’s people have no access to the Internet. |
C.OneWeb’s satellites will make it possible for most people to be served with 5G. |
D.Without the Internet, poor communities can hardly help themselves out of poverty. |
A.The risks of furthering space exploration. |
B.The value of setting up space stations. |
C.The way we could monitor our earth. |
D.The features of microsatellites. |
“We finally have the first look at our Milky Way black hole, Sagittarius A*,”an international team of astrophysicists(天文物理学家)and researchers from the Event Horizon Telescope team announced
For years, the supermassive black hole in the dark center of the Milky Way galaxy
What made capturing the image extra
“Although we cannot see the black hole
The
10 . Researchers have discovered the oldest black hole ever observed, dating from the dawn of the universe, and found that it is “eating” its host galaxy to death.
The international team, led by the University of Cambridge, used the James Webb Space Telescope (JWST) to detect the black hole, which dates from 400 million years after the big bang. The results, which lead author Professor Roberto Maiolino says are “a giant leap forward”, are reported in the journal Nature.
This surprisingly massive black hole even exists so early in the universe challenges our assumptions about how black holes form and grow. The size of this newly-discovered black hole suggests that they might form in other ways: they might be ‘born big’ or they can eat matter at a rate that’s five times higher than had been thought possible. Like all black holes, this young black hole devours material from its host galaxy to fuel its growth.
According to standard models, supermassive black holes form from the remains of dead stars, which collapse and may form a black hole about a hundred times the mass of the Sun. If it grew in an expected way, this newly-detected black hole would take about a billion years to grow to its observed size. However, the universe was not yet a billion years old when this black hole was detected.
The young host galaxy, called GN-z11, is a compact galaxy, about one hundred times smaller than the Milky Way, but the black hole is likely harming its development. When black holes consume too much gas, it pushes the gas away like an ultra-fast wind. This “wind” could stop the process of star formation, slowly killing the galaxy, but it will also kill the black hole itself, as it would cut off the black hole’s source of “food”.
Maiolino says that the gigantic leap forward provided by JWST makes this the most exciting time in his career. “It’s a new era: the giant leap is like upgrading from Galileo’s telescope to a modern telescope overnight,” he said. “The universe has been quite generous in what it’s showing us, and this is just the beginning.”
1. What does the underlined word “devours” mean in Paragraph 3?A.Changes. | B.Swallows. | C.Observes. | D.Forms. |
A.Because the host galaxy is too small. |
B.Because the black hole is killing itself. |
C.Because the “wind” ceases star formation. |
D.Because black holes produce too much gas. |
A.Favorable. | B.Intolerant. | C.Doubtful. | D.Ambiguous. |
A.The black hole took a billion years to achieve its size. |
B.Supermassive black holes are assumed to form overnight. |
C.The new discovery of the host galaxy is a giant leap forward. |
D.The host galaxy and the black hole can be destroyed by the “wind”. |