4.Thanks largely to the Kepler space telescope,astronomers have discovered more than 2,000 planets in the universe.Kepler's final goal is to find worlds similar to Earth-places where there's a chance that alien life might exist.
But the search for life will still not be easy.It will be important to choose the best possible targets.That's the reasoning behind two new rating systems (評(píng)估體系)proposed by Washington State University environmental scientist Dirk Schulze-Makuch,along with nine other colleagues.
The first rating system is called the Earth Similarity Index,or ESI.That's just what it sounds like:it's a measure of how closely an alien world matches Earth in terms of size and temperature.The temperature is important because liquid water is an important part for life.
The size of the planet seems important too.If a planet is too small,like Mars,it might not have enough gravity (引力) to hold on to its atmosphere.If the planet is too big,gravity might have pulled in too much atmosphere,which would create too much pressure at the surface.A world four or five times as large as Earth might be able to support life.But anything bigger than that could cause problems.
This second system is called the Planetary Habitability Index,or PHI.It includes planets that have a solid surface of some kind,protected by an atmosphere of some kind.Other things necessary under the PHI system are some sort of energy source(sunlight);some sort of chemical environment that allows the formation of complex molecules(分子); and the presence of liquid-but not necessarily water.
The search will get easier as technology improves.Still,these new ways of looking for alien life give us our best chance of learning if somewhere out we have galactic (銀河的)relatives.
66.Kepler isD.
A.a(chǎn) scientist B.a(chǎn)n organization C.a(chǎn) system D.a(chǎn) telescope
67.According to the 5th paragraph,to support life,the following are necessary EXCEPTB.
A.a(chǎn) solid surface
B.water
C.a(chǎn) protective atmosphere
D.a(chǎn)n energy source
68.Why is there no life in Mars?C
A.Because the Mars is too hot to keep the water.
B.Because the sun is far away from the Mars.
C.Because the Mars can't keep the atmosphere.
D.Because there is not any other energy in Mars.
69.We can infer that the text isD.
A.a(chǎn) description of natural resources
B.a(chǎn) research report
C.a(chǎn) book review
D.a(chǎn)n introduction to space science
70.What does the text mainly talk about?A
A.New ways to look for alien life.
B.Goals to find worlds similar to Earth.
C.Systems to search for more planets.
D.Reports made by Dirk Schulze-Makuch.
分析 本文屬于說明文閱讀,作者通過這篇文章主要向我們描述了尋找外星生命的新方法和重要條件.
解答 66.D.細(xì)節(jié)理解題.根據(jù)第一段Thanks largely to the Kepler space telescope,astronomers have discovered more than 2,000 planets in the universe可知開普勒是天文望遠(yuǎn)鏡;故選D.
67.B.細(xì)節(jié)理解題.根據(jù)文章some sort of chemical environment that allows the formation of complex molecules(分子); and the presence of liquid-but not necessarily water可知維持生命需要一種液體但不一定是水;故選B.
68.C.細(xì)節(jié)理解題.根據(jù)第四段If a planet is too small,like Mars,it might not have enough gravity (引力) to hold on to its atmosphere可知火星沒有生命是因?yàn)闆]有足夠的引力維持大氣層;故選C.
69.D.推理判斷題.根據(jù)最后一段The search will get easier as technology improves.Still,these new ways of looking for alien life give us our best chance of learning if somewhere out we have galactic (銀河的)relatives可知文章是對(duì)于空間科學(xué)的介紹;故選D.
70.A.推理判斷題.根據(jù)最后一段The search will get easier as technology improves.Still,these new ways of looking for alien life give us our best chance of learning if somewhere out we have galactic (銀河的)relatives可知文章主要講尋找外星生命的新方法;故選A.
點(diǎn)評(píng) 考察學(xué)生的細(xì)節(jié)理解和推理判斷能力,做細(xì)節(jié)理解題時(shí)一定要找到文章中的原句,和題干進(jìn)行比較,再做出正確的選擇.在做推理判斷題不要以個(gè)人的主觀想象代替文章的事實(shí),要根據(jù)文章事實(shí)進(jìn)行合乎邏輯的推理判斷.