Life on Other PlanetsIn 1961, scientists set up a gigantic, sensitive apparatus to collect - 试题答案网问答

第1题

The author believes that other life forms are so far away from our planet that we could ne

ver meet them.

A．Y

B．N

C．NG

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第2题

The author believes that life on other planets can take on forms ______ because even life

on our own planet assumes such strange and various forms.

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第3题

At the end of the passage the author suggests that（） A．it is impossible for

At the end of the passage the author suggests that（）

A．it is impossible for life to exist on other planets.

B．earthlike life could only exist on a few planets.

C．life could exist on only one planet in a million.

D．life could exist on a great number of planets.

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第4题

When Geoff Marcy was 14, his parents bought him a telescope. Every night, he would go onto

the roof outside his window to see the wonders of the sky.

"What excited me most was whether there were planets (行星)in other solar (太阳的) systems where life might exist," he says. "I decided to try to find planets orbiting (沿......轨道运行) other stars like our Sun."

And he did. "My fellow researcher, Paul Butler, and I found our first planet in 1995," Dr. Marcy says. "We worked for ten years without finding anything! But we stuck with it, and our patience paid off."

Since then, the two scientists have discovered 65 of the more than 100 planets found orbiting other stars. Dr. Marcy and Dr. Butler also spotted the first "family" of three planets. In June 2002 they announced another discovery: a Jupiter-like (像木星一样的) planet orbiting star 55 Caned. At first, the two researchers found only planets that orbit close to stars. Recently, the scientists found planets farther out. The planet orbiting 55 Cancri is a major breakthrough: it is the first sighting of a large gas planet about the same distance from the star as Jupiter is from the Sun. Why is this important？ Scientists think that life on Earth may exist because of two special features (征) in our solar system. The first is Jupiter.

"Because it's so big, Jupiter pulls comets and asteroids (小行星), or they all come and hit the Earth." Dr. Marcy explains. "Without Jupiter, life on Earth would likely have been destroyed." A second feature is that Earth is a rocky planet where liquid water, which is necessary for life, can exist. Unlike gas planets, rocky planets like Earth have surfaces where water can gather in pools and seas, which may support life. A huge space exists between the Jupiter-like planet and two other planets that lie close to 55 Caneri. Is there an Earth-like planet in the space, too small for us to notice？ If so, says Dr. Marcy, "We would have two striking similarities to our solar system: a Jupiter-like planet and an Earth-like planet. And there may be life!"

What can we learn about Dr. Marcy from the passage？

A．He is fond of watching Jupiter.

B．He is from a scientist family.

C．He dislikes working with Paul Butler.

D．He is interested in finding life in outer space.

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第5题

When imaginative men turn their eyes towards space and wonder whether life exists in any p

art of it, they may cheer themselves by remembering that life need not resemble closely the life that exists on Earth. Mars looks like the only planet where life like ours could exist, and even this is doubtful. But there may be other kinds of life based on other kinds of chemistry, and they may multiply on Venus or Jupiter. At least we cannot prove at present that they do not.

Even more interesting is the possibility that life on their planets may be in a more advanced stage of evolution. Present-day man is in a peculiar and probably temporary stage. His individual units retain a strong sense of personality. They are, in fact, still capable under favorable circumstances of leading individual lives. But man's societies are already sufficiently developed to have enormously more power and effectiveness

than the individuals have.

It is not likely that this transitional situation will continue very long on the evolutionary time scale. Fifty thousand year's from now man's societies may have become so close-knit that the individuals retain no sense of separate personality. Then little distinction will remain between the organic parts of the multiple organism and the inorganic parts (machines) that have been constructed by it. A million years further on man and his machines may have merged as closely as the muscles of the human body and nerve cells that set them in motion.

The explorers of space should be prepared for some' such situation. If they arrive on a foreign planet that has reached an advanced stage (and this is by no means impossible), they may find it being inhabited by a single large organism composed of many closely cooperating units.

The units may be "secondary"-machines created millions of years ago by a previous form. of life and given the will and ability to survive and reproduce. They may be built entirely of metals and other durable materials. If this is the case, they may be much more tolerant of their environment, multiplying under conditions that would destroy immediately any organism made of carbon compounds and dependent on the familiar car bon cycle.

Such creatures might be relics of a past age, many millions of years ago, when their planet was favorable to the origin of life, or they might be immigrants from a favored planet.

Humans on Earth today are characterized by______.

A．their existence as free and separate beings

B．their capability of living under favorable conditions

C．their great power and effectiveness

D．their strong desire for living in a close-knit society

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第6题

根据短文回答 36～40 题。 Life in the Universe Many scientists today are convinced that

根据短文回答 36～40 题。

Life in the Universe

Many scientists today are convinced that life exists elsewhere in the universe － life probably much like that on our own planet. They reason in the folio, wing way.

As far as astronomers (天文学家) can determine, the entire universe is built of the same matter. They have no reason to doubt that matter obeys the same laws in every part of the universe. Therefore, it is reasonable to guess that other stars, with their own planets, were born in the same way as our own solar system. What we know of life on earth suggests that life will arise wherever the proper conditions exist.

Life requires the right amount and kind of atmosphere. This .eliminates all those planets in the universe that are not about the same size and weight as the earth. A smaller planet would lose its atmosphere; a larger one would hold too much of it.

Life also requires a steady supply of heat and light. This eliminates double stars, or tars that flare up (闪耀) suddenly. Only single stab that are steady sources of heat and light like our sun would qualify.

Finally, life could evolve only if the planet is just the right distance from its sun. With a weaker sun than our own, the planet would have to be closer to it. With a stronger sun, it would have to be farther away.

If we suppose that every star in the universe has a family of planets, then how many planets might support life？ First, eliminate those stars that are not like our sun. Next, eliminate most of their planets; they are either too far from or too close to their suns. Then eliminate all those planets which are not the same size and weight as the earth. Finally, remember that the proper conditions do not necessarily mean that life actually does exist on a planet. It may not have begun yet, or it may have already died out.

This process of elimination seems to leave very few planets on which earthlike life might be found. However, even if life could exist on only one planet in a million, there are so many billions of planets that this would still leave a vast number on which life could exist.

第 36 题 Astronomers believe that matter in different parts of the universe（）

A．obeys different laws

B．obeys one common law

C．obeys the same laws

D．obeys no common law

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第7题

Life in the UniverseMany scientists today are convinced that life exists elsewhere in the

universe---life probably much like that on our own planet. They reason in the following way.

As far as astronomers can determine, the entire universe is built of the same matter. They have no reason to doubt that matter obeys the same laws in every part of the universe. Therefore, it is reasonable to guess that other stars, with their own planets, were born in the same way as our own solar system. What we know of life on earth suggests that life will arise wherever the proper conditions exist.

Life requires the right amount and kind of atmosphere. This eliminates all those planets in the universe that are not about the same size and weight as the earth. A smaller planet would lose its atmosphere; a larger one would hold too much of it.

Life also requires a steady supply of heat and light. This eliminates double stars, or stars that flare up suddenly. Only single stars that are steady sources of heat and light like our sun would qualify.

Finally, life could evolve only if the planet is just the right distance from its sun. With a weaker sun than our own, the planet would have to be closer to it. With a stronger sun, it would have to be farther away.

If we suppose that every star in the universe has a family of planets, then how many planets might support life？ First, eliminate those stars that are not like our sun. Next eliminate most of their planets; they are either too far from or too close to their suns. Then eliminate all those planets which are not the same size and weight as the earth. Finally, remember that the proper conditions do not necessarily mean that life actually does exist on a planet. It may not have begun yet, or it may have already died out.

This process of elimination seems to leave very few planets on which earthlike life might be found. However, even if life could exist on only one planet in a million, there are so many billions of planets that this would still leave a vast number on which life could exist.

第36题：Astronomers believe that matter in different parts of the universe

A) has different laws.

B) has one common law.

C) shares the same laws

D) shares no common law.

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第8题

Many scientists today are convinced that life exists elsewhere in the universe—life probab

ly much like that on our own planet. They reason in the following way.

As far as astronomers can determine, the entire universe is built of the same matter. They have no reason to doubt that matter obeys the same laws in every part of the universe. Therefore, it is reasonable to guess that other stars, with their own planets, were born in the same way as our own solar system. What we know of life on earth suggests that life will arise wherever the proper conditions exist.

Life requires the right amount and kind of atmosphere. This eliminates all those planets in the universe that are not about the same size and weight as the earth. A smaller planet would lose its atmosphere, a larger one would hold too much of it.

Life also required a steady supply of heat and light. This eliminates double stars, or stars that flare up suddenly. Only single stars that are steady sources of heat and light like our sun would qualify.

Finally, life could evolve only if the planet is just the right distance from its sun. With a weaker sun than our own, the planet would have to be closer to it. With a stronger sun, it would have to be farther away.

If we suppose that every star in the universe has a family of planets, then how many planets might support life？ First, eliminate those stars that are not like our sun. Next, eliminate most of their planets, they are either too far from or too close to their suns. Then eliminate all those planets which are not the same size and weight as the earth. Finally, remember that the proper conditions do not necessarily mean that life actually does exist on a planet. It may not have begun yet, or it may have already died out.

This process of elimination seems to leave very few planets on which earthlike life might be found. However, even if life could exist on only one planet in a million, there are so many billions of planets that this would still leave a vast number on which life could exist.

Astronomers believe that matter in different parts of the universe ______.

A．has different laws

B．has one common law

C．shares the same laws

D．shares no common law

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第9题

In 1961, scientists set up gigantic, sensitive apparatus to collect radio waves from the f

ar reaches of space, hoping to discover in them some mathematical pattern indicating that the waves were sent out by other intelligent beings. Someday the experiment may succeed.

What reason is there to think that we may actually detect intelligent life in outer space？ To begin with, modern theories of the development of stars suggest that almost every star has some sort of family of planets. So any star like our own sun (and there are billions of such stars in the universe) is likely to have a planet situated at such a distance that it would receive about the same amount of radiation as the earth.

Furthermore, such a planet would probably have the same general composition as our own; so, allowing a billion years or two--or three--there would be a very good chances for life to develop, if current theories of the origin of life are correct.

But intelligent life7 Life that has reached the stage of being able to send radio waves out into space in a conscious pattern7 Our own planet may have been in existence for five billion years and may have had life on it for two billion, but it is only in the last fifty years that we are capable of sending radio waves into space. From this it might seem that even if there were no technical problems involved, the chance of receiving signals from another planet would be extremely small.

This does not mean that intelligent life at our level does not exist somewhere. There are such an unimaginable number of stars that, even at such miserable odds, it seems certain that there are millions of intelligent life forms scattered through space. The only trouble is, none may be within our reach. Perhaps none never will be; perhaps the distances that separate us from our fellow inhabitants of this universe will forever remain too great to be conquered. And yet it is conceivable that someday we may come across one of them or one of them may come across us. What would they be like, these extraterrestrial(地球以外的) creatures？

If the radio waves had reached our planet one hundred years before, we would have______.

A．sent an immediate answer

B．sent an alarm against extraterrestrial attack

C．sent a short reply

D．sent no answer

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第10题

11：Reading Comprehension For centuries, explorers have risked their lives venturing into t

he unknown for reasons that were to varying degrees economic and nationalistic. Columbus went west to look for better trade routes to the Orient and to promote the greater glory of Spain. Lewis and Clark journeyed into the American wilderness to find out what the U. S. had acquired when it purchased Louisiana, and the Appolo astronauts rocketed to the moon in a dramatic show of technological muscle during the cold war. Although their missions blended commercial and political-military imperatives, the explorers involved all accomplished some significant science simply by going where no scientists had gone before. Today Mars looms as humanity's next great terra incognita. And with doubtful prospects for a short-term financial return, with the cold war a rapidly fading memory and amid a growing emphasis on international cooperation in large space ventures, it is clear that imperatives other than profits or nationalism will have to compel human beings to leave their trucks on the planet's reddish surface. Could it be that science, which has long played a minor role in exploration, is at last destined to take a leading role？ The question naturally invites a couple of others: Are there experiments that only humans could do on Mars？ Could those experiments provide insights profound enough to justify the expense of sending people across interplanetary space？ With Mars the scientific stakes are arguably higher than they have ever been. The issue of Whether life ever existed on the planet, and whether it persists to this day, has been highlighted by mounting evidence that the Red Planet once had abundant stable, liquid water and by the continuing controversy over suggestions that bacterial fossils rode to Earth on a meteorite from Mars. A more conclusive answer about life on Mars, past or present, would give researchers invaluable data about the range of conditions under which a planet can generate the complex chemistry that leads to life. If it could be established that life arose independently on Mars and Earth, the finding would provide the first concrete clues in one of the deepest mysteries in all of science: the prevalence of life in the universe. By saying "With Mars the scientific stakes are arguably higher than they have ever been" in the fourth paragraph, the author means that ______.

A.with Mars the risks involved are much greater than any previous space ventures

B.in the ease of Mars, the rewards of scientific exploration can be very high

C.in the case of Mars, much more research funds are needed than ever before

D.with Mars, scientists argue, the fundamental interests of science are at issue

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