1 . The emergence of black holes undoubtedly marks the beginning of a revolution. Black holes have many peculiar properties, such as the alteration of space and time, the radiation of gravitational waves and so on. Scientists are still trying to study the properties and evolution of black holes in order to better understand the origin and evolution of the universe.

Recently, a team of astronomers may have found a solo-wandering black hole using a strange trick of gravity called microlensing (微透镜效应), but the results still have to be confirmed.

Sometimes it’s tough being an astronomer. Nature likes to hide the most interesting things from easy observation. Take, for example, black holes. Except for the strange quantum (量子) phenomenon of Hawking radiation, black holes are completely black. They don’t emit a single bit of radiation – they only absorb, hence their name.

To date, the only way astronomers have been able to spot black holes is through their influence on their environments. For example, if an orbiting star gets a little too close, the black hole can absorb the gas from that star, causing it to heat up as it falls. We can watch as stars dance around the giant black hole at the center of the Milky Way.

Even the famed pictures of the black holes in the center of the Milky Way and the M87 galaxy(星系) aren’t photographs of the black holes themselves. Instead, they are radio images of everything around them.

But surely not all black holes have other light-emitting objects around them to help us find them. To find these wanderers, astronomers have tried their luck with microlensing. We know that heavy objects can bend the path of light around them. This is a prediction of Einstein’s general theory of relativity, and the slight bending of starlight around our own sun was one of the first successful tests of the theory.

Microlensing is pretty much what the name suggests. When astronomers get extremely lucky, a wandering black hole and pass between us and a random distant star. The light from that star bends around the black hole because of its gravity, and from our point of view, the star will appear to temporarily flare in brightness.

And when I say “extremely lucky” I mean it. Despite trying this technique for over a decade, it is only now that astronomers have found a candidate black hole through microlensing. Two teams used the same data, a microlensing event recorded from both the OGLE (Optical Gravitational Lensing Experiment) telescope in Chile and the MOA (Microlensing Observations in Astrophysics) telescope in New Zealand. One team found that the mass was somewhere around seven times the mass of the sun – definitely black hole territory. But the other team estimated a much smaller mass, around 2-4 times the mass of the Sun. If the true mass of the object is at the lower end of that spectrum (光谱), then the wanderer is probably not a black hole.

1. Why does the author say it is hard to be an astronomer?

A．Einstein’s theory is hard to understand.

B．Many things in nature are not easy to observe.

C．Understanding the evolution of the universe is not easy.

D．Whether the black hole has been found remains to be seen.

2. What is the example in Para. 4 trying to prove?

A．Stars’ wandering in black holes.

B．Black holes’ absorbing the star’s gas.

C．The relationship between stars’ heating and black holes.

D．Finding black holes by observing environmental changes.

3. What does the author tell us about the discovery of black holes?

A．People can often find black holes with glowing objects.

B．Research groups can work together to find black holes.

C．Glowing objects around black holes help us find them sometimes.

D．Understanding the properties of black holes helps find them.

4. What conclusion can we draw from the last paragraph?

A．To persevere in the end is to win.

B．Facts speak louder than words.

C．Failure is the mother of success.

D．Things are not always what they seem.

2 . If a scientist sees a unicorn (独角兽), she’ll probably want to see more than one before telling the world about her discovery. But sometimes one unicorn is enough.

In 2007 an astronomer named Duncan Lorimer reported finding a new kind of astronomical event. It was a brief stream of energy so powerful that it could reach Earth from a galaxy billions of light-years away. He called it a fast radio burst (FRB). This remarkable find, if real, could make huge contributions to the study about universe. He predicted there would be many more – but that year, he spotted just one.

It’s not unheard of for one event to kick off a whole new field of scientific inquiry. Still it’s rare. When Lorimer’s paper came out in the journal, it was not surprising that many were skeptical. “Sometimes, what seems like a remarkable scientific discovery turns out to be an error in the data,” some commented.

Later, a young graduate student was assigned the task of finding more FRBs. Using the same radio telescope Lorimer once used, she found more bursts that just looked like FRBs. But because of the ways they appeared in the telescope data, she was virtually certain that they were some other kind of radio interference and gave them another name: perytons. As years ticked by and no more FRBs were discovered, some astronomers began to conclude Lorimer had found nothing more than an unusual example of one of these perytons.

Good news: in 2011, there was a report of a second FRB. Four more were found in 2013. Bad news: all of them came from the same Lorimer’s radio telescope. But ultimately, in 2014, there was a report from another radio telescope. More discoveries started showing up from other telescopes on a somewhat regular basis. At last the conversation about FRBs shifted – from whether they were real to where they came from.

Years of research have passed by since then. Now, Victoria Kaspi, a physics professor and principal investigator on the FRB team, predicts that once the more advanced telescopes come online in 2024, the location and distance of most FRBs detected can be found out, which will provide “golden opportunities for astronomers to study the large-scale structure of the universe”.

Finally, this “unicorn” story came to a somehow surprising end. Several years ago, a team reanalyzed the same data from the radio telescope by which Lorimer found the first FRB. There was one more that they had previously missed. Since then, other teams have analyzed even older data and found FRBs in those datasets too.

“They were just sitting there, waiting to be discovered by better techniques,” Lorimer says.

1. Which of the following has the closest meaning to the underlined word in paragraph 3?

A．Optimistic.

B．Curious.

C．Supportive.

D．Doubtful.

2. Why did the author mention unicorns in the first paragraph?

A．To suggest that the new scientific discovery was a myth.

B．To imply magical creatures may actually exist in the world.

C．To symbolize the previously unknown and unseen discoveries.

D．To quote an incident that once happened in the field of science.

3. Why was it bad news that other FRBs found also came from Lorimer’s telescope?

A．Because it might mean the results were not reliable.

B．Because they were all found by a young graduate student.

C．Because these were given the name perytons and were not real FRBs.

D．Because not every astronomer had the same type of telescope as Lorimer.

4. What can we imply from this passage?

A．It’s possible for just one event to start a new field of scientific research.

B．New scientific discoveries can’t be made without advanced research techniques.

C．Scientists shouldn’t deny new discoveries even if they lack evidence temporarily.

D．Scientists should be careful to distinguish new discoveries from errors in the datasets.

3 . Directions: Fill in eat blank with a proper word chosen form the box. Each word can be used only once. Note that there is one word more than you need.

A. arrives       B. observable   C. boundless.       D. contained. E. distancing. F. expansion G. lies       H. parallel       I. perceiving       J. threads       K. volume

What Comes After Space?

Looking at a clear night sky you witness the vastness of space, which holds everything humans know to exist. To find out what     1     beyond a good place to start is to determine where the universe ends. However, the problem is that scientist are uncertain about where space ends or whether it ends at all.

The     2     universe

The furthest humans can see out into space,using all the technology currently available to us,is 46 billion light years (alight year is the distance that light can travel in one year,and is equivalent to about 9. 5 million million kilometres). The     3     of space that humans can see is called the visible universe. Beyond this, it remains a mystery whether it’s an expanse of more galaxies and stars or possibly the edge of the universe. Some think that the universe is     4    , meaning space goes on forever in every direction. In this case,there is nothing after space,because space is everything.

Moving further away

Experts have captured images of the entire Earth from space,and some astronauts have personally witnessed its beauty from orbit. Perhaps     5     the limits of the universe would also be possible too, if only humans knew where to go to look for it.

Another challenge is the universe’s rapid     6    . As galaxies move further away their light   takes longer to reach us. Eventually, some galaxies may be so distant that their light never     7    . This might imply that any edge— and whatever is on the other side — is increasingly     8     itself from us. Regardless of these uncertainties, scientists still spend a lot of time thinking about what comes after space.

Many universes?

It’s possible that there isn’t just one universe, and that our universe is just one small part of a “multiverse”. Perhaps our universe is     9     within its own distinct region of space, separated from others by vast expanses of nothingness. Or maybe     10     universes exist pressed tightly against each other. Getting an idea of the universe’s true shape may help astronomers find out whether it has an edge. What comes after that could be an even great mystery.

4 . 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.

2.

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

3.

A．Their surface features.	B．Their chemical composition.
C．Their temperature.	D．Their age.

4.

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.

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.     1    

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.     2     Space observers believe that it is on course to intersect (相交) with the moon. Bill Gray, who writes software to track near-Earth objects, has said the rocket will very likely hit the far side of the moon, near the equator. “This is the first unintentional case of space junk hitting the moon of which I’m aware,” Gray added.

    3     Because of the unpredictable effect of sunlight “pushing” on the rocket and “difficulty in measuring rotation (旋转) periods”, its orbit may be slightly altered. “But these unpredictable effects are very small,” Gray wrote. He added that further observations were needed to decide the precise time and location of the impact. In a recent blog post, he wrote that the rocket has made a close lunar flyby, and will definitely make an impact.

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.”     4     They believe that the event will allow for observation of valuable lunar materials ejected (弹射) by the rockets strike.

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 . The elements other than hydrogen and helium （氮气）exist in such small quantities that it is accurate to say that the universe somewhat more than 25 percent helium by weight and somewhat less than 25 percent hydrogen.

Astronomers have measured the amount of helium throughout our galaxy （星 系）and in other galaxies as well. Helium has been found in old stars, in relatively young ones, and in the distant objects known as quasars. Helium nuclei have also been found in cosmic rays that fall on the earth （cosmic ‌“rays” are not really a form of radiation; they consist of rapidly moving particles （颗粒）of numerous different kinds）. It doesn’t seem to make very much difference where the helium is found. Its amount never seems to vary much. In some places, there may be slightly more of it; in others, slightly less, but the proportion of helium to hydrogen nuclei always remains about the same.

Helium is created in stars. In fact, nuclear reactions that turn hydrogen to helium are responsible for most of the energy that stars produce. However, the amount of helium that could have been produced in this manner can be calculated, and it turns out to be no more than a few percent. The universe has not existed long enough for this figure to be significantly greater. Consequently, if the universe is somewhat more than 25 percent helium now, then it must have been about 25 percent helium at a time near the beginning.

However, when the universe was less than one minute old, no helium could have existed. Calculations indicate that before this time temperatures were too high and particles of matter were moving around much too rapidly. It was only after the one-minute point that helium could exist. By this time, the universe had cooled sufficiently. But the nuclear reactions that led to the formation of helium went on for only a relatively short time. By the time the universe was a few minutes old, helium production had effectively ceased.

1. According to the passage, helium is_________.

A．difficult to detect

B．the oldest element in the universe

C．a common element in quasars

D．the second element in the universe in amount

2. Why does the author mention “cosmic rays‌” in paragraph 2?

A．To explain how the universe began.

B．As part of a list of things containing helium.

C．As an example of an unsolved astronomical puzzle.

D．To explain the abundance of hydrogen in the universe.

3. Most of the helium in the universe was formed _________.

A．in invisible space

B．in a very short time

C．before most of the hydrogen

D．during the first minute of the universe’s existence

7 . 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.

1. All the five theories imply that _____.

A．time is flexible	B．time is constant
C．time does go forth and back	D．time does exist in some way

2. Which theory doesn’t include time?

A．Theory 1.	B．Theory 2.
C．Theory 3.	D．Theory 4.

3. According to the passage, which of the following statements is true of dark energy?

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.

8 . With billions of stars in our galaxy (银河系), many circled by planets, the chances are there should be advanced life capable of reaching out to us. Yet after decades of looking and listening, we have found ___________.

This apparent conflict is known as Fermi’s paradox- Some have used it to argue that the search for extraterrestrial(外星球的)intelligence (SETI) is sure to ___________ .

But a mathematical analysis of SETI searches done so far claims that the usual explanation for the paradox— that there is nobody out there—is ___________. Instead, it suggests the best explanation is simply that we have barely scratched the surface in our ___________ for extraterrestrial intelligence.

Jason Wright at Pennsylvania State University and his colleagues analysed the many variables involved in SETI, which involves searching for radio signals from other ___________ . These include what to look for, where to look, how often and for how long. They then devised an equation that computes the ___________ of the galaxy checked so far. The team says that the volume of the galaxy that has been checked by SETI so far is roughly___________ to just a single bathtub of water in the world’s oceans.

“You don’t have to do a calculation to say we’ve only just ___________ ,” says Duncan Forgan at the University of St Andrews, UK, who is a member of the UK SETI research network. ”But they’ve done a nice job of showing the huge scale of the problem___________.“

As well as putting SETI in context, the equation can help researchers see which search techniques have been used less than others. ____________ , we only developed the technology to listen for higher radio frequencies quite recently. ”But we’re getting better at that, so that variable will now shrink,“ says Forgan.

However, advances in ____________ will only take us so far. Certain variables, such as how often a message from space might be repeated, cannot be____________. A signal sent once a year can only be listened out for once a year. ”There are things we can do better and things we can’t,” says Forgan. “We just have to ____________ and wait for the universe to do its thing.”

Forgan has a book coming out that discusses 66 potential ____________ for Fermi’s paradox. They include the possibility that Earth is somehow unusual in its ability to harbour intelligent life or that technological civilisations are rare. Or perhaps they are ____________ but short-lived. “Genetic or nuclear disasters might wipe you out,” says Forgan.

1.

A．nothing

B．something

C．anything

D．everything

2.

A．arrive

B．join

C．fail

D．improve

3.

A．possible

B．simple

C．relative

D．false

4.

A．hunt

B．love

C．service

D．region

5.

A．individuals

B．civilisations

C．surroundings

D．organisations

6.

A．source

B．centre

C．edge

D．part

7.

A．subject

B．equivalent

C．available

D．committed

8.

A．remembered

B．mentioned

C．described

D．started

9.

A．progressively

B．mathematically

C．synthetically

D．occasionally

10.

A．For example

B．What’s more

C．In summary

D．By comparison

11.

A．technology

B．computation

C．radioactivity

D．astronomy

12.

A．measured

B．challenged

C．changed

D．interpreted

13.

A．set off

B．sit back

C．put up

D．take down

14.

A．demands

B．benefits

C．explanations

D．applications

15.

A．weird

B．boring

C．exciting

D．common

9 . Directions: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one more word than you need.

A. magic       B. alternative       C. flawlessly       D. housed       E. detective       F. premature G. supply       H. works       I. packed       J. acceptable       K. completely

NASA Begins High-Stakes Repair to Hubble Space Telescope

NASA engineers are trying to carry out repairs on the Hubble Space Telescope, which stopped working on June 13 as a result of a problem with the payload computer on board.

After a month of trying, engineers with the space agency were unable to restart the computer, so the Hubble team will switch to a(n)     1     power unit on Thursday. If successful, it will take several days to     2     return the observatory to normal operations, NASA reported.

The Hubble Telescope has shaped our understanding of the cosmos for over 30 years. It proved that almost every galaxy has a supermassive black hole at its heart. It also played a vital role in the discovery of dark matter — a mysterious substance that can’t be seen.

The payload computer is used to control and coordinate Hubble’s scientific instruments. The computer’s programs also analyze and manipulate the data it collects.

NASA engineers believe the problem is related to the Power Control Unit, or PCU, which ensures a steady voltage     3     to the payload computer. The PCU is     4     with the payload computer in the Science Instrument Command and Data Handling unit. “The team’s analysis suggests that either the voltage level from the regulator is outside of     5     levels, or the secondary protection circuit has degraded over time and is trapped in this inhibit state,” according to the NASA statement.

The telescope itself and science instruments remain “healthy and in a safe configuration,” the statement confirmed. The Hubble Space Telescope, which orbits 340 miles above Earth’s surface, hasn’t always functioned     6    . A similar repair was performed in 2008, when another part of the PCU failed.

A replacement for Hubble is in the     7    . NASA’S James Webb Space Telescope is expected to launch later this year. The large, infrared telescope appears to become the next great     8     in the universe.

But it’s     9     to give up on Hubble, said Don Lincoln, a senior scientist from NASA. “The instrument has generated scientific data leading to countless papers and also gorgeous images that have transfixed the science-interested public. In that sense, an inoperable Hubble would be a devastating loss,” he wrote in an opinion piece.

“The best-case scenario is one in which both are operating, and we must wait for those clever engineers to work their     10     to see if that is possible.”

10 . Back in 2015 my colleague Adam Frank of the University of Rochester and I were having lunch near Columbia University's campus in New York City. As at Fermi's lunch 65 years earlier, the conversation was about the nature of spacefaring species. And inspired by Fermi's mental calculation, we were trying to craft an investigative strategy that made the fewest possible unsubstantiated assumptions and that could be somehow tested or constrained with real data. At the center of this exercise was the simple thought that waves of exploration or settlement could come and go across the galaxy, with humans happening to come into being in one of the lonely periods.

This idea relates to Hart's original fact: that there is no evidence here on Earth today of extraterrestrial（外星的）explorers. But it goes further by asking whether we can obtain meaningful limits on galactic（星系的）life by constraining the exact length of time over which Earth might have gone unvisited. Perhaps long, long ago extraterrestrial explorers came and went. A number of scientists have, over the years, discussed the possibility of looking for artifacts that might have been left behind after such visitations of our solar system. The necessary scope of a complete search is hard to predict, but the situation on Earth alone turns out to be a bit more manageable. In 2018 another of my colleagues, Gavin Schmidt of NASA's Goddard Institute for Space Studies, together with Adam Frank, produced a critical assessment of whether we could even tell if there had been an earlier industrial civilization on our planet.

As fantastic as it may seem, Schmidt and Frank argue—as do most planetary scientists—that it is actually very easy for time to erase essentially all signs of technological life on Earth. The only real evidence after a million or more years would boil down to isotopic or chemical stratigraphic anomalies—odd features such as synthetic molecules, plastics or radioactive fallout. Fossil remains and other paleontological markers are so rare that they might not tell us anything in this case.

Indeed, modern human urbanization covers only on order of about 1 percent of the planetary surface, providing a very small target area for any paleontologists（古生物学家）in the distant future. Schmidt and Frank also conclude that nobody has yet performed the necessary experiments to look exhaustively for such non-natural signatures on Earth. The bottom line is, if an industrial civilization on the scale of our own had existed a few million years ago, we might not know about it. That absolutely does not mean one existed; it indicates only that the possibility cannot be completely eliminated.

1. The word “unsubstantiated”（in paragraph 1）is closest in meaning to ________.

A．unconscious

B．unknown

C．unnatural

D．unsupported

2. What assumption was the author and his colleague's investigative strategy built on?

A．No other species have ever settled on Earth except human beings.

B．Extraterrestrial explorers come and go at increasingly short intervals.

C．No spacefaring species have visited the Earth since humans emerged.

D．Extraterrestrial explorers once built an industrial civilization on Earth.

3. It can be inferred from the passage that if we want to prove if there used to be an industrial civilization on Earth, we should________.

A．turn to isotopic or chemical stratigraphic anomalies

B．find as many signs of technological life as possible

C．unearth more fossil remains than we do now

D．leave behind synthetic things like plastics

4. According to the passage, what are Schmidt and Frank most likely to agree with?

A．Human urbanization should be expanded for the sake of research.

B．We cannot say for sure that no civilization existed before ours.

C．Non-natural signatures on Earth have been studied exhaustively.

D．An industrial civilization came into being a few million years ago.