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 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. 1. 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. 2. The existence of life depends on all of the following factors EXCEPT A) the right amount of atmosphere.B) our own solar system. C) steady heat and light D) the right distance from the sun. 3. Which of the following statements is INCORRECT? A) The planet must be as big and heavy as the earth. B) Proper conditions are essential to the existence of life C) Double stars can provide steady light and heat. D) The distance between a planet and its sun should be right. 4. What kind of planet might NOT support life? A) Most of the planets of the stars. B) Stars similar to our sun. C) Planets similar to the earth. D) Planets with proper conditions. 5. At the end of the passage the author suggests that A) it is impossible for life to exist on 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. 答案:CBCAD
下一篇: 职称英语考试综合类经典阅读题(1)
2016高考英语总复习精选课件(江苏专用)牛津译林版选修7《Unit 2 Fit for life》
2016高考英语总复习精选课件(江苏专用)牛津译林版选修8《UNIT3-4》佳作晨背·文思泉涌
2016高考英语总复习精选课件(江苏专用)牛津译林版选修6《Unit 4 Helping people around the world》
2016高考英语总复习精选课件(江苏专用)牛津译林版选修7《Unit 4 Public transport》
2016高考英语总复习精选课件(江苏专用)牛津译林版选修6《Unit 1 Laughter is good for you》
2016高考英语总复习精选课件(江苏专用牛津译林版)语法专项突破:五、非谓语动词
2016高考英语总复习精选课件(江苏专用牛津译林版)专项提能计划:阅读理解(四)
2016高考英语总复习精选课件(江苏专用牛津译林版)专项提能计划:完形填空(二)
2016高考英语总复习精选课件(江苏专用牛津译林版)语法专项突破:三、形容词和副词
2016高考英语总复习精选课件(江苏专用)牛津译林版选修7《UNIT1-2》句型公式妙笔生花
2016高考英语总复习精选课件(江苏专用)牛津译林版选修7《UNIT3-4》佳作晨背·文思泉涌
2016年高考总复习优化英语课件(四川专用)写作教程:Module1
2016高考英语总复习精选课件(江苏专用牛津译林版)专项提能计划:书面表达(七)
2016高考英语总复习精选课件(江苏专用)牛津译林版选修8《Unit 2 The universal language》
2016高考英语总复习精选课件(江苏专用牛津译林版)专项提能计划:书面表达(三)
2016高考英语总复习精选课件(江苏专用牛津译林版)专项提能计划:书面表达(二)
2016高考英语总复习精选课件(江苏专用牛津译林版)语法专项突破:九、名词性从句
2016高考英语总复习精选课件(江苏专用牛津译林版)专项提能计划:阅读理解(三)
2016高考英语总复习精选课件(江苏专用)牛津译林版选修7《Unit 1 Living with technology》
2016年高考总复习优化英语课件(四川专用)写作教程:Module3
2016年高考总复习优化英语课件(四川专用)写作教程:Module4
2016高考英语总复习精选课件(江苏专用牛津译林版)专项提能计划:书面表达(六)
2016高考英语总复习精选课件(江苏专用牛津译林版)语法专项突破:四、动词和动词短语
2016年高考总复习优化英语课件(四川专用)写作教程:Module2
2016高考英语总复习精选课件(江苏专用牛津译林版)语法专项突破:一、代词
2016高考英语总复习精选课件(江苏专用)牛津译林版选修8《Unit 1 The written world》
2016高考英语总复习精选课件(江苏专用)牛津译林版选修7《Unit 3 The world online》
2016高考英语总复习精选课件(江苏专用牛津译林版)语法专项突破:十、状语从句
2016高考英语总复习精选课件(江苏专用牛津译林版)专项提能计划:书面表达(五)
2016高考英语总复习精选课件(江苏专用牛津译林版)语法专项突破:十一、特殊句式