题目内容
A meteorite (陨石) flew fast across the sky and exploded over central Russia on Friday, raining fireballs over a vast area and causing a shock wave that smashed windows, damaged buildings and injured l,200 people.
People heading to work in Chelyabinsk heard what sounded like an explosion, saw a bright light and then felt the shock wave.
According to Russian space agency Roscosmos, the fireball, travelling at a speed of 30km per second, had burnt very brightly across the horizon, leaving a long white trail that could be seen as far as 200km away. Car alarms went off, thousands of windows shattered and mobile phone networks were disrupted.
“I was driving to work, it was quite dark, but it suddenly became as bright as if it were day,” said Viktor Prokofiev, 36, a resident of Yekaterinburg in the Urals Mountains. “I felt like I was blinded by headlights.”
The meteorite, which weighed about 20 tons and may have been made of iron, entered Earth’s atmosphere and broke apart 30-50km above ground, according to Russia’s Academy of Sciences.
The energy released when it entered the Earth’s atmosphere was about several thousand tons, the academy said, the power of a small atomic weapon exploding.
No deaths were reported, but the Emergencies Ministry said 20,000 rescue and clean-up workers were sent to the region after President Vladimir Putin told Emergencies Minister Vladimir Puchkov to ease the disruption and help the victims.
The Interior Ministry said about l,200 people had been injured, at least 200 of them children, and most from broken pieces of glass.“While events this big are rare, an impact that could cause damage and death could happen every century or so. Unfortunately there is absolutely nothing we can do to stop impacts.”
51. When did the meteorite incident happen?
A. At midnight. B. In the early morning.
C. In the late morning. D. In the evening.
52. According to the text, the meteorite explosion caused _________.
A. some deaths B. road accidents
C. communication problems D. building collapse
53. The Russian government’s response to the incident was ________.
A. a little slow but effective B. quick and serious
C. cold and slow D. quick but ineffective
54. It can be inferred that the loss caused by meteorites _________.
A. is nearly unavoidable B. happens every few years
C. can be avoided D. is hard to estimate
BCBA
When we look at the sky and see a bright light moving quickly across it or coming towards the earth, we talk about seeing a “shooting star” or a “falling star”. These moving lights are not, in fact, stars at all. They are small pieces of matter from outer space, which burn up as they enter the Earth’s atmosphere. The correct name of them is meteoroids. Any pieces that make it to the Earth’s surface without completely burning up are known as meteorites. A meteor is actually the name given to the light we see when a meteoroid is burning up.
When a meteorite hits the Earth at speeds between 11 and 72 kilometers a second, it can do amazing damage. A very large meteorite could knock the earth out of its orbit. If this happened, all life on Earth would probably become extinct(灭绝). The path we follow around the Sun would change and as a result the Earth would become either much hotter or much colder. This change in temperature would affect sea levels and the amount of water in rivers. There would either be huge floods, which would cover most of the land with water, or the oceans would dry up and there would be a drought, which means a long period of time without rain. Either way, nothing could survive. If a large meteorite landed in the sea it would almost certainly cause tsunamis, which would race towards the land, destroying everything in their paths.
Although it is unlikely the Earth will be struck by a meteorite large enough to do that kind of damage, there is evidence of fairly large meteorites hitting the Earth in the past. In 1908 a large area of forest in Tunguska, Siberia was destroyed by a meteorite that came apart just before it hit the ground. The moon, however, has about three billion craters陨石坑caused by meteorites impacting影响 its surface. The reason more meteorites have reached the surface of the moon than the surface of the Earth is that the moon does not have enough atmosphere for the meteorites to burn up in. some of the meteorites that have reached the Earth’s surface have done considerable damage. Some scientists believe it was a change of climate caused by meteorites hitting the Earth that resulted in the extinction of the dinosaurs and other large prehistoric animals.
Scientists are especially interested in meteorites because they contain information about the solar system. It is widely believed by scientists that most meteorites are produced by collisions(碰撞) between asteroids (small planets). These collisions probably happened many billions of years ago. This means the physical and chemical structure of a meteorite can give scientists information about the early days of the universe.
【小题1】 The story is about ___.
A.floods caused by meteors |
B.matter from outer space |
C.life on Earth millions of years ago |
D.meteorites that have damaged the moon |
A.three billion craters |
B.fewer craters than the moon |
C.more craters than the moon |
D.a thinner atmosphere than the moon |
A.they were hit by meteors |
B.meteorites landed on their nests |
C.meteorites landed and changed the climate |
D.they could no longer breathe the atmosphere |
A.small planets |
B.the same as asteroids |
C.from broken parts of asteroids |
D.the light we see when meteoroids hit our atmosphere |
Mars Was Not Always Bitterly Cold
Scientists at the California Institute of Technology (Caltech) have reported evidence that Mars was warmer and wetter long ago than it is today. The Caltech scientists say they have directly established the temperature of Mars four billion years ago. At least, they established the surface temperature on part of the planet at that time. The researchers say it is the first such evidence to be discovered and presented.
The Caltech scientists say carbonate(碳酸盐) minerals formed on Mars at about eighteen degrees Celsius. They reached the finding after studying a meteorite(陨石) that had its beginnings near the Martian surface.
Today, the average temperature on Mars is sixty-three degrees below zero Celsius.
The finding was reported on the website of the National Academy of Sciences. Caltech Assistant Professor Woody Fischer helped to prepare the report. He says eighteen degrees Celsius is not especially cold or hot. He says this makes the finding extremely interesting. Knowing the temperature can give scientists an idea of the climate on Mars long ago. It can also help them decide whether the planet had liquid water. Spacecraft orbiting Mars have shown what appear to be rivers, lakebeds and mineral deposits. These pictures suggest that, at one time, water did flow there. Mars Rover vehicles and other spacecraft have confirmed the information.
Caltech Geology Professor John Eiler was another writer of the report. He says knowing the temperature of Mars from long ago provides valuable information. It shows that early in the planet's history, at least part of Mars could support a climate like that of Earth.
The meteorite the scientists examined is one of the oldest known rocks in the world. It is called the Allan Hills meteorite. Its name came from the place in Antarctica where it was found in 1984. The meteorite is believed to have blown loose from the Mars' surface when another space rock struck its "home."
【小题1】 The underlined word “establish” in Paragraph 1 probably means “___________”.
A.to set up |
B.to make people accept a belief |
C.to discover or prove |
D.to start having a relationship with others |
A.By studying Allan Hills meteorite. |
B.By using spacecraft orbiting Mars. |
C.By studying minerals gathered on Mars |
D.By studying a meteorite on the Martian surface. |
A.Measuring the temperature of Mars. |
B.Taking photos of the surface of Mars. |
C.Confirming that there is water flowing on Mars. |
D.Finding where human beings will probably land on Mars. |
A.From its original place on Mars. |
B.From where it was found on the earth. |
C.From the name of the scientist who found it. |
D.From the name of the aircraft that discovered it |
A.In a biography of scientists. |
B.In a geography magazine. |
C.In an environment report. |
D.In a science report. |
Mars Was Not Always Bitterly Cold
Scientists at the California Institute of Technology (Caltech) have reported evidence that Mars was warmer and wetter long ago than it is today. The Caltech scientists say they have directly established the temperature of Mars four billion years ago. At least, they established the surface temperature on part of the planet at that time. The researchers say it is the first such evidence to be discovered and presented.
The Caltech scientists say carbonate(碳酸盐) minerals formed on Mars at about eighteen degrees Celsius. They reached the finding after studying a meteorite(陨石) that had its beginnings near the Martian surface.
Today, the average temperature on Mars is sixty-three degrees below zero Celsius.
The finding was reported on the website of the National Academy of Sciences. Caltech Assistant Professor Woody Fischer helped to prepare the report. He says eighteen degrees Celsius is not especially cold or hot. He says this makes the finding extremely interesting. Knowing the temperature can give scientists an idea of the climate on Mars long ago. It can also help them decide whether the planet had liquid water. Spacecraft orbiting Mars have shown what appear to be rivers, lakebeds and mineral deposits. These pictures suggest that, at one time, water did flow there. Mars Rover vehicles and other spacecraft have confirmed the information.
Caltech Geology Professor John Eiler was another writer of the report. He says knowing the temperature of Mars from long ago provides valuable information. It shows that early in the planet's history, at least part of Mars could support a climate like that of Earth.
The meteorite the scientists examined is one of the oldest known rocks in the world. It is called the Allan Hills meteorite. Its name came from the place in Antarctica where it was found in 1984. The meteorite is believed to have blown loose from the Mars' surface when another space rock struck its "home."
1. The underlined word “establish” in Paragraph 1 probably means “___________”.
A.to set up |
B.to make people accept a belief |
C.to discover or prove |
D.to start having a relationship with others |
2.How did the scientists reach the finding?
A.By studying Allan Hills meteorite. |
B.By using spacecraft orbiting Mars. |
C.By studying minerals gathered on Mars |
D.By studying a meteorite on the Martian surface. |
3.According to the fourth paragraph, what have spacecraft orbiting Mars done?
A.Measuring the temperature of Mars. |
B.Taking photos of the surface of Mars. |
C.Confirming that there is water flowing on Mars. |
D.Finding where human beings will probably land on Mars. |
4.How did Allan Hills meteorite get its name?
A.From its original place on Mars. |
B.From where it was found on the earth. |
C.From the name of the scientist who found it. |
D.From the name of the aircraft that discovered it |
5. Where can we most probably read this passage?
A.In a biography of scientists. |
B.In a geography magazine. |
C.In an environment report. |
D.In a science report. |
When we look at the sky and see a bright light moving quickly across it or coming towards the earth, we talk about seeing a “shooting star” or a “falling star”. These moving lights are not, in fact, stars at all. They are small pieces of matter from outer space, which burn up as they enter the Earth’s atmosphere. The correct name of them is meteoroids. Any pieces that make it to the Earth’s surface without completely burning up are known as meteorites. A meteor is actually the name given to the light we see when a meteoroid is burning up.
When a meteorite hits the Earth at speeds between 11 and 72 kilometers a second, it can do amazing damage. A very large meteorite could knock the earth out of its orbit. If this happened, all life on Earth would probably become extinct(灭绝). The path we follow around the Sun would change and as a result the Earth would become either much hotter or much colder. This change in temperature would affect sea levels and the amount of water in rivers. There would either be huge floods, which would cover most of the land with water, or the oceans would dry up and there would be a drought, which means a long period of time without rain. Either way, nothing could survive. If a large meteorite landed in the sea it would almost certainly cause tsunamis, which would race towards the land, destroying everything in their paths.
Although it is unlikely the Earth will be struck by a meteorite large enough to do that kind of damage, there is evidence of fairly large meteorites hitting the Earth in the past. In 1908 a large area of forest in Tunguska, Siberia was destroyed by a meteorite that came apart just before it hit the ground. The moon, however, has about three billion craters陨石坑caused by meteorites impacting影响 its surface. The reason more meteorites have reached the surface of the moon than the surface of the Earth is that the moon does not have enough atmosphere for the meteorites to burn up in. some of the meteorites that have reached the Earth’s surface have done considerable damage. Some scientists believe it was a change of climate caused by meteorites hitting the Earth that resulted in the extinction of the dinosaurs and other large prehistoric animals.
Scientists are especially interested in meteorites because they contain information about the solar system. It is widely believed by scientists that most meteorites are produced by collisions(碰撞) between asteroids (small planets). These collisions probably happened many billions of years ago. This means the physical and chemical structure of a meteorite can give scientists information about the early days of the universe.
1.The story is about ___.
A.floods caused by meteors |
B.matter from outer space |
C.life on Earth millions of years ago |
D.meteorites that have damaged the moon |
2.The Earth has ___.
A.three billion craters |
B.fewer craters than the moon |
C.more craters than the moon |
D.a thinner atmosphere than the moon |
3.Some scientists believe the dinosaurs became extinct because ___.
A.they were hit by meteors |
B.meteorites landed on their nests |
C.meteorites landed and changed the climate |
D.they could no longer breathe the atmosphere |
4.Meteors are ___.
A.small planets |
B.the same as asteroids |
C.from broken parts of asteroids |
D.the light we see when meteoroids hit our atmosphere |