题目内容
After spending years searching for a planet with life, scientists may have found one. In September 2010, a team of US scientists discovered an Earth-sized planet called Gliese 581g. It has a surface temperature neither too hot nor too cold for liquid(液态)water. Scientists think there is a chance that the planet could have life.
The planet Gliese 581g goes around a star called Gliese 581, which is about 20 light-years from Earth. That is about 194 trillion(万亿)kilometres -500 million times farther away from us than the moon.
A spacecraft traveling at a one-tenth of the speed of light would reach Gliese 581g within about 220 years. A human can’t live that long, but robotic explorers could make the job easier. However, our fastest spacecraft don’t come anywhere near that one-tenth light-speed mark.
At present, scientists don’t know what the surface might be like on Gliese 581g. What they know is that the planet is at the right distance from its star to have liquid water. It’s also at the right distance to have an atmosphere that could protect the water if it is on the surface.
Although spacecraft won’t be getting there anytime soon, one way to look for life on Gliese 581g is to turn our radio telescopes(望远镜)towards the planet and search for radiation(放射). By studying the radiation, scientists would find out about the chemicals(化学物质)around the planet and discover if Gliese 581g has an atmosphere. If it has one, studying the atmosphere would give us a good idea whether the planet has life or not. But it’ll probably be many years before we can do this properly.
People have been arguing about whether there is alien life on Gliese 581g. Any discussion about alien life is just guessing at this point, according to its discoverers.
1.What did scientists find in September 2010?
A.A planet with water. B.A planet similar to the earth.
C.A planet without life. D.A planet near the earth.
2.According to the article, Gliese 581g ________.
A.is at the right distance from its star B.moves around the earth
C.is as far away from us as the moon D.can be reached in about 220 years
3.Paragraph 5 is mainly about ______.
A.the possibility of living on Gliese 581g
B.the kinds of chemicals around Gliese 581g
C.the way of looking for life on Gliese 581g
D.the aim of studying the radiation on Gliese 581g
4.Which of the following is the best title for the passage above?
A.Gliese 581g, a Likely Living Planet B.Gliese 581, a Likely Living Planet
C.Gliese 581g and Its Star D.Gliese 581g and Radiation
1.A
2.A
3.C
4.A
【解析】
试题分析:这篇文章主要讲的是科学家在2010年9月发现的一颗非常类似地球的行星Gliese 581g。
1.细节题。根据文章In September 2010, a team of US scientists discovered an Earth-sized planet called Gliese 581g. It has a surface temperature neither too hot nor too cold for liquid(液态)water.可知,2010年9月,科学家发现了一个表面存在液态水的行星。故选A
2.细节题。根据文章What they know is that the planet is at the right distance from its star to have liquid water.可知,gliese 581g行星位于红矮星gliese 581的“适居带”Goldilocks zone量程内。故选A
3.细节题。文章第五段主要讲的是在行星Gliese 581g上寻找生命的方法。故选C
4.主旨题。这篇文章主要讲的是科学家在2010年9月发现的一颗非常类似地球的行星Gliese 581g。故选A
考点:科普类说明文
点评:本文的思路清晰,结构明确。首先对作者所说明的事情进行理解。本文细节题很多,对于细节题,学生在理解全文的基础上要对题目中关键字在文章中迅速定位,找到相对应的出处,答题比较备选答案的区别及和文章信息最相关的是哪个,即那个就为正确答案。
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