Scientists have discovered a “monster black hole” so massive that, in theory, it shouldn’t exist. It’s a stellar (恒星) black hole — the type that forms after stars die, collapse, and explode. Researchers had previously believed that the size limit was no more than 20 times the mass of our sun because as these stars die, they lose most of their mass through explosions that expel (排出) matter and gas swept away by stellar winds.
This theory has now been toppled by LB-1, the newly discovered black hole. Located about 15,000 light years away, it has a mass 70 times greater than our sun, according to a press release from the Chinese Academy of Sciences.
The findings were published by Chinese researchers in the journal Nature on Wednesday. “Black holes of such mass should not even exist in our galaxy, according to most of the current models of stellar evolution,” said Liu Jifeng, head of the team that made the discovery.
“LB-1 is twice as massive as what we thought possible. Now theorists will have to take up the challenge of explaining its formation.”
Scientists are now scratching their heads at how LB-1 got so huge.
The Chinese team has proposed a number of theories. LB-1’s sheer size suggests that it “was not formed from the collapse of only one star,” the study said — instead, it could potentially be two smaller black holes orbiting each other.
Another possibility is that it formed from “fallback supernova.” This is when a supernova — the last stage of an exploding star — ejects (排出) material during the explosion, which then falls back into the supernova, creating a black hole.
This fallback formation is theoretically possible, but scientists have never been able to prove or observe it. If this is how LB-1 formed, then we may have “direct evidence for this process” for the first time, the study said.
There are several types of black holes and stellar black holes like LB-1 are on the smaller side, according to NASA. Supermassive black holes are much bigger — they can be billions of times the mass of our sun.
Scientists believe supermassive black holes may be connected to the formation of galaxies, as they often exist at the center of the mass star stems but it is still not clear exactly how, or which form first.
1.Why does the writer write the article?
A.To report the great achievement Chinese scientists have made in black hole theory.
B.To inform the readers of the basic knowledge about the black hole.
C.To share with the readers the new development of the black hole discovery.
D.To demonstrate the significance of discovering new black holes for science.
2.What does the underlined word “toppled” mean in the second paragraph?
A.overturned B.supported C.suspected D.tested
3.Which of the following about LB-1 is true to the passage?
A.It is the biggest black hole ever discovered.
B.It lost only a small part of its mass through explosion.
C.It couldn’t have been formed from the collapse of one star,
D.Its discovery may lead to some breakthrough in the “fallback formation theory”.
4.Which of the following is right according to the passage?
A.If the sun in our galaxy dies some of its mass will be taken away by stellar winds.
B.A massive supernova will be formed and then exploded if the sun in our galaxy dies.
C.“The Milky Way” was formed after a supermassive black hole collapsed and exploded.
D.If “the Milky Way” dies, a supermassive black hole will be formed after its death.
高一英语阅读理解中等难度题
Scientists have discovered a “monster black hole” so massive that, in theory, it shouldn’t exist. It’s a stellar (恒星) black hole — the type that forms after stars die, collapse, and explode. Researchers had previously believed that the size limit was no more than 20 times the mass of our sun because as these stars die, they lose most of their mass through explosions that expel (排出) matter and gas swept away by stellar winds.
This theory has now been toppled by LB-1, the newly discovered black hole. Located about 15,000 light years away, it has a mass 70 times greater than our sun, according to a press release from the Chinese Academy of Sciences.
The findings were published by Chinese researchers in the journal Nature on Wednesday. “Black holes of such mass should not even exist in our galaxy, according to most of the current models of stellar evolution,” said Liu Jifeng, head of the team that made the discovery.
“LB-1 is twice as massive as what we thought possible. Now theorists will have to take up the challenge of explaining its formation.”
Scientists are now scratching their heads at how LB-1 got so huge.
The Chinese team has proposed a number of theories. LB-1’s sheer size suggests that it “was not formed from the collapse of only one star,” the study said — instead, it could potentially be two smaller black holes orbiting each other.
Another possibility is that it formed from “fallback supernova.” This is when a supernova — the last stage of an exploding star — ejects (排出) material during the explosion, which then falls back into the supernova, creating a black hole.
This fallback formation is theoretically possible, but scientists have never been able to prove or observe it. If this is how LB-1 formed, then we may have “direct evidence for this process” for the first time, the study said.
There are several types of black holes and stellar black holes like LB-1 are on the smaller side, according to NASA. Supermassive black holes are much bigger — they can be billions of times the mass of our sun.
Scientists believe supermassive black holes may be connected to the formation of galaxies, as they often exist at the center of the mass star stems but it is still not clear exactly how, or which form first.
1.Why does the writer write the article?
A.To report the great achievement Chinese scientists have made in black hole theory.
B.To inform the readers of the basic knowledge about the black hole.
C.To share with the readers the new development of the black hole discovery.
D.To demonstrate the significance of discovering new black holes for science.
2.What does the underlined word “toppled” mean in the second paragraph?
A.overturned B.supported C.suspected D.tested
3.Which of the following about LB-1 is true to the passage?
A.It is the biggest black hole ever discovered.
B.It lost only a small part of its mass through explosion.
C.It couldn’t have been formed from the collapse of one star,
D.Its discovery may lead to some breakthrough in the “fallback formation theory”.
4.Which of the following is right according to the passage?
A.If the sun in our galaxy dies some of its mass will be taken away by stellar winds.
B.A massive supernova will be formed and then exploded if the sun in our galaxy dies.
C.“The Milky Way” was formed after a supermassive black hole collapsed and exploded.
D.If “the Milky Way” dies, a supermassive black hole will be formed after its death.
高一英语阅读理解中等难度题查看答案及解析
Astronomers and scientists think that a black hole is a region of space ______ which matter has fallen and _______ which nothing can escape.
A．into; from B．towards; towards
C．out of; from D．through; through
高一英语单项填空中等难度题查看答案及解析
Scientists say they have discovered a possible cure for all five known Ebola viruses. Antibodies (抗体) that are used in the cure were discovered in the blood of a survivor.
Kartik Chandran of the Albert Einstein College of Medicine helped discover the antibodies. They are described online in the journal Cell. Chandran says studies of the antibody in non-human primates (非灵长类动物) have shown positive results. He says he is optimistic that the antibodies can be used to protect and treat people, too.
he virus was given the name Ebola because the first recorded outbreak of the disease took place along the Ebola River in the Democratic Republic of Congo (DRC) — then known as Zaire
— in 1976.
Since then, there have been about 24 Ebola outbreaks in Africa, including one happening now in the DRC. Nine people have been infected and three people have died. The most recent Ebola epidemic took place from 2013 to 2016. It killed more than 11,000 people and infected
29,000 in Liberia, Guinea and Sierra Leone.
During that epidemic, researchers were studying an anti-Ebola drug called Zmapp. Doctors began using it even before the study was complete. Zmapp uses antibodies discovered in mice. They use the body’s natural immune system to fight infection. If the drug is given within five days after Ebola infection symptoms appear, it can cure the disease.
Promising results
But researcher Kartik Chandran says Zmapp is effective only against Ebola Zaire. It does not fight the other four known Ebola viruses.
Chandran says the recently discovered human antibodies attack and destroy all five of the viruses. Researchers say the antibodies work by interfering with a process that the disease uses to infect and multiply inside cells. Chandran says scientists discovered the antibodies in just six months.
The drug company Mapp Pharmaceutical Incorporated is now testing the antibodies in monkeys that have been exposed to Ebola. Spokespeople for the company say the antibodies have
so far been safe and effective．
Chandran says he hopes the antibodies can also be tested in people soon. And, he says, he hopes they can finally be used both as a treatment and as a vaccine (疫苗) to prevent people from getting Ebola in the first place.
1.Where should the subtitle “A challenging history” be placed?
A. Between paragraphs 1 and 2． B. Between paragraphs 2 and 3．
C. Between paragraphs 3 and 4． D. Between paragraphs 4 and 5．
2.What do we know about Zmapp?
A. The study about it was a failure． B. It mainly uses human antibodies．
C. Its medical function is limited． D. It is only effective for five days．
3.Which of the following is true?
A. Ebola virus can multiply inside cells．
B. DRC suffers most from Ebola virus．
C. Ebola virus poses no threat to monkeys．
D. Human antibody relies on body’s immune system．
4.What is the best title of the passage?
A. It’s time for Ebola Virus to disappear
B. Scientists discover cure for Ebola Virus
C. Zmapp loses advantage in fighting Ebola
D. A drug company contributes to fighting Ebola
高一英语阅读理解困难题查看答案及解析
Scientists have discovered a special biological behavior in dolphins（海豚） that could lead to a treatment for late-onset diabetes（晚发的糖尿病） in humans. Studies on dolphins found that healthy dolphins switch into a diabetic-like state overnight when they are not feeding, but return to normal when they eat the following morning.
The extraordinary finding has led scientists to suggest that dolphins have “genetic switch” that allows them to imitate diabetes while they are not feeding for a night, without suffering any ill effect.
If researchers can identify a similar genetic pathway in human, they may be able to develop drugs to effectively switch off diabetes. Some 2.2 million people in Britain have type 2 (or late-onset) diabetes, a figure that is expected to reach 4 million by 2025 as a consequence of rising levels of obesity（肥胖）.
The tissues of people with type 2 diabetes have become resistant to insulin（胰岛素）so they lose the ability to control sugar levels in their blood. The condition can damage the heart, eyes, kidneys（肾脏） and nerves and contribute to 5% of all deaths, according to the World Healthy Organisation.
Dolphins appear to imitate diabetes to keep high levels of blood sugar when food is rare. Like humans, dolphins need some sugar in their blood for their brains to function normally. Venn-Watson’s team analysed 1,000 blood samples（样本） from 52 dolphins while they didn’t eat anything overnight and fed in the morning. At night time, the dolphins’ metabolism（新陈代谢）changed greatly and showed similar characteristics to that seen in people with type 2 diabetes.
“It is our hope that this discovery can lead to new ways to prevent, treat and maybe even cure diabetes in humans,” said Stephanie Venn-Watson, director of clinical research at the National Marine Foundation in San Diego.
1.What’s the main idea of the passage?
A. Humans get some idea of treating diabetes from dolphins.
B. Dolphins can switch into a diabetic-like state overnight.
C. Humans can suffer the same disease as dolphins.
D. Dolphins should be fed regularly to avoid diabetes.
2.The key to applying the finding to curing human diabetes lies in ____________.
A. producing insulin in a larger amount
B. developing drugs from healthy dolphins
C. identifying a similar genetic pathway in human
D. analysing more blood samples from hungry dolphins
3.Which of the following statements is TRUE according to the passage?
A. Scientists have found a similar genetic switch in humans.
B. More British people will suffer type 2 diabetes due to obesity.
C. 2.2 million people with type 2 diabetes die in Britain every year.
D. Dolphins imitate diabetes to avoid a high blood sugar level.
4.What will happen to dolphins if not fed for a night according to Venn-Watson?
A. Their metabolism breaks down.
B. They become resistant to insulin.
C. Their heart and kidneys are damaged.
D. They keep high levels of blood sugar.
高一英语阅读理解中等难度题查看答案及解析
A healthy amount of sunshine may be the secret to staying young. British scientists have discovered.
Vitamin D is produced naturally by the skin in response to (对…的反应) sunlight and may help to slow the ageing process and protect against heart disease, according to the study.
Researchers from King's College London studied 2,160 women aged between 18 and 79, looking at their telomeres-a biological marker of ageing found in DNA. As people get older, their telomeres get shorter and they become more susceptible (易受伤害的) to certain illnesses.
But the study found women with high levels of vitamin D had comparatively longer telomeres-a sign of being biologically younger and healthier.
The study suggests vitamin D may help to slow down the ageing process of DNA, and therefore the ageing process as a whole.
Lead researcher Dr Brent Richards said, "These results are exciting because they show for the first time that people who have higher levels of vitamin D may age more slowly than people with lower levels of vitamin D." This could help to explain how vitamin D has a protective effect on many ageing related diseases, such as heart disease and cancer."
Professor Tim Spector, a co-author of the report, added, " Although it might sound absurd(荒唐的), it's possible that the same sunshine which may increase our risk of skin cancer may also have a healthy effect on the general ageing process.
Vitamin D made by the action of sunlight on the skin accounts for 90 percent of the body's supply, but lower levels can also be got through food such as fish, eggs and breakfast cereals(粥).
Other studies have suggested the vitamin plays a key role in protecting against cancer and heart disease.
1.A certain amount of sunshine helps people stay young because _________.
A. people feel happy and energetic in the sun
B. vitamin D may help to slow the ageing process
C. sunshine protects people against heart disease
D. vitamin D makes one's skin look young and healthy
2.From Brent Richards, we know that ________.
A. sunlight causes skin cancer to people with high level of vitamin D
B. the study generally has a healthy effect on the general ageing process
C. the higher levels of vitamin D people have, the more slowly people may age
D. vitamin D can only be got from fish, eggs and breakfast cereals
3.What can we infer from the passage?
A. Sunlight does more good than harm to our health.
B. Telomeres are important as they are signs of ageing of the DNA.
C. Sunlight can be dangerous as it causes skin cancer.
D. Vitamin D can also be gained from food.
4.What is the best title of the passage?
A. Secret of Staying Young
B. Sunlight and Vitamin D
C. Vitamin D Helps Slow Ageing
D. Sunlight and Health
高一英语阅读理解中等难度题查看答案及解析
A healthy amount of sunshine may be the secret to staying young. British scientists have discovered.
Vitamin D is produced naturally by the skin in response to(对…的反应) sunlight and may help to slow the ageing process and protect against heart disease, according to the study.
Researchers from King’s College London studied 2,160 women aged between 18 and 79, looking at their telomeres--- a biological marker of ageing found in DNA. As people get older, their telomeres get shorter and they become more susceptible(易受伤害的) to certain illnesses.
But the study found women with high levels of vitamin D had comparatively longer telomeres--- a sign of being biologically younger and healthier.
The study suggests vitamin D may help to slow down the ageing process of DNA, and therefore the ageing process as a whole.
Lead researcher Dr Brent Richards said, “These results are exciting because they show for the first time that people who have higher levels of vitamin D may age more slowly than people with lower levels of vitamin D.” This could help to explain how vitamin D has a protective effect on many ageing related diseases, such as heart disease and cancer.”
Professor Tim Spector, a co-author of the report, added, “Although it might sound absurd
(荒唐的), it’s possible that the same sunshine which may increase our risk of skin cancer may also have a healthy effect on the general ageing process.”
Vitamin D made by the action of sunlight on the skin accounts for 90 percent of the body’s supply, but lower levels can also be got through food such as fish, eggs and breakfast cereals(粥).
Other studies have suggested the vitamin plays a key role in protecting against cancer and heart disease.
1. A certain amount of sunshine helps people stay young because _____.
A. people feel happy and energetic in the sun
B. sunshine protects people against heart disease
C. vitamin D makes one’s skin look young and healthy
D. vitamin D may help to slow the ageing process
2.From Brent Richards, we know that _____.
A. sunlight causes skin cancer to people with high level of vitamin D
B. the study generally has a healthy effect on the general ageing process
C. vitamin D can only be got from fish, eggs and breakfast cereals
D. the higher levels of vitamin D people have, the more slowly people may age
3.What can we infer from the passage?
A. Telomeres are important signs of ageing of the DNA.
B. Sunlight can be dangerous as it causes skin cancer.
C. Sunlight does a great deal of good to our health.
D. Vitamin D can also be gained from food.
4. What is the best title of the passage?
A. Secret of Staying Young B. Vitamin D Helps Slow Ageing
C. Sunlight and Vitamin D D. Sunlight and Health
高一英语阅读理解中等难度题查看答案及解析
A healthy amount of sunshine may be the secret to staying young. British scientists have discovered.
Vitamin D is produced naturally by the skin in response to(对…的反应) sunlight and may help to slow the ageing process and protect against heart disease, according to the study.
Researchers from King’s College London studied 2,160 women aged between 18 and 79, looking at their telomeres--- a biological marker of ageing found in DNA. As people get older, their telomeres get shorter and they become more susceptible(易受伤害的) to certain illnesses.
But the study found women with high levels of vitamin D had comparatively longer telomeres--- a sign of being biologically younger and healthier.
The study suggests vitamin D may help to slow down the ageing process of DNA, and therefore the ageing process as a whole.
Lead researcher Dr Brent Richards said, “These results are exciting because they show for the first time that people who have higher levels of vitamin D may age more slowly than people with lower levels of vitamin D.” This could help to explain how vitamin D has a protective effect on many ageing related diseases, such as heart disease and cancer.”
Professor Tim Spector, a co-author of the report, added, “ Although it might sound absurd(荒唐的), it’s possible that the same sunshine which may increase our risk of skin cancer may also have a healthy effect on the general ageing process.
Vitamin D made by the action of sunlight on the skin accounts for 90 percent of the body’s supply, but lower levels can also be got through food such as fish, eggs and breakfast cereals(粥).
Other studies have suggested the vitamin plays a key role in protecting against cancer and heart disease.
1.A certain amount of sunshine helps people stay young because _________.
A. vitamin D may help to slow the ageing process
B. sunshine protects people against heart disease
C. vitamin D makes one’s skin look young and healthy
D. people feel happy and energetic in the sun
2.From Brent Richards, we know that ________.
A. sunlight causes skin cancer to people with high level of vitamin D
B. the higher levels of vitamin D people have, the more slowly people may age
3.What can we infer from the passage?
A. Telomeres are important as they are signs of ageing of the DNA.
B. Sunlight can be dangerous as it causes skin cancer.
C. Sunlight does more good than harm to our health.
D. Vitamin D can only be gained from food.
高一英语阅读理解中等难度题查看答案及解析
Researchers have discovered the first Earth-sized planet. It was first marked by scientists' using NASA's Kepler telescope(望远镜), so it's called Kepler﹣186f. It lies about 500 light years from Earth and goes around its star.The planet is the right distance from its star for water: not too close or not too far. Water is one important condition that scientists guess is necessary for life. So it could have water and possible life. It's called a true Earth cousin.
"This planet is an Earth cousin, not an Earth twin," said Barclay, who is among a team of scientists reporting on the discovery in the magazine Science this week.
"It's very exciting to find a planet similar to the Earth，"Barclay said. "It's not easy work because things change as we get more measurements."
Scientists don't know anything about the air of Kepler﹣186f, but it will be a task for future telescopes which can study for chemicals that have something to do with life.
"It's possible for life to live in this planet, but that doesn't mean there is life in it," Barclay said.
So far, scientists have found nearly 1,800 planets in the universe.
"The past year has seen a lot of progress in the search for Earthlike planets. Kepler﹣186f is very important because it is the first planet that is the same temperature and is almost the same size as Earth,"scientist David Charbonneau wrote in an email.
1.Scientists have already found about ________ planets now.
A. 500 B. 186 C. 1,800 D. 1,801
2.Which of the following about Kepler﹣186f is NOT true according to the passage?
A. It could have water and possible life, so perhaps we might live there.
B. It's almost as hot as and as large as Earth.
C. In the future，scientists will study the chemicals of it by telescope.
D. It's an Earth﹣like planet.
3.What is the best title of the passage？
A. Space research
B. Journey to space
C. Is there water and possible life in Kepler﹣186f？
D. Scientists discover the most Earth-like planet
高一英语阅读理解中等难度题查看答案及解析
_____ by a black hole, Li Yanping was so frightened at first, but he calmed down later and
tried his best to escape.
| A．Caught | B．Catching | C．To catch | D．Catch |
高一英语单项填空简单题查看答案及解析
--Tom seems to have discovered all about the event.
-- ____.
A. So he did B. So do he
C. So he has D. So has he
高一英语单项填空中等难度题查看答案及解析