职称英语（理工类）模拟试题 1
（46） ______. Most spacecraft are unmanned these days but missions are still unpredictable; a spacecraft was destroyed on the approach to Mars only last month.
Our sights are set on Mars because people still hope to find life there－not the movie director's idea of a Martian （火星）, but rather microscopic forms of life hidden beneath the surface to protect them from the cold. Another possible home to life is Jupiters moon, Europe, which seems to have slush （雪泥, 烂泥） beneath its ice crust that is kept warm by tides. （47） ______.
Using our near-space environment is the aim for the foreseeable future, people are even setting up businesses to offer trips in space to rich members of the general public. （48） ______ .It builds on the success of the space shuttle （航天飞机）, which proved very flexible and allowed masses of scientific experiments in micro-gravity; and also on Mars, which told us a lot about the physical effects of long duration space flight. The Russians kept it going much longer than anyone expected－you were almost blase （玩腻了的） about the latest crisis.
Beyond our own solar system, we will keep up the search for planets that might sustain life. （49） ______ .You can say: "There are so many stars, some of them with planets, that some of those planets must be conducive （有利的） to live?" But even if that were true, that life might have happened millions of years ago or be going to happen millions of years in the future. （50） ______ .
A. The real excitement surrounds the international space station, which will be built over the next five or six years by countries working collaboratively （共同的） on a spacecraft for the first time.
B. The prospects aren't great.
C. Spacecrafts may help mankind to realize the dream of living on other planets.
D. Although putting people into orbit is now routine, traveling further is not.
E. We now know that stars other than our sun have planets, but there's still a big difference between finding planets and finding life.
F. But exploration is a long way off.
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Stars
The old belief that the universe never changes is quite （51） ______. Even （52） ______ the invention of the telescope, astronomers noticed that bright stars suddenly appear in the sky and then later （53） ______. These stats were called "novae" because they were thought to be （54） ______. In fact we now know that they are really old stars which are slowly dying.
Novae are old stars which are slowly dying. （55） ______ they do so, they let out huge clouds of material, sometimes as large as the earth, and these explode into space （56） ______ a speed of about 8,000,000 kilometers per hour. When this happens, the hotter parts of the star become （57） ______, and this is why novae are so bright. Although the explosions are huge on a human scale, they only （58） ______ a small part of the dying star's energy. The death is a slow one and the star may continue to explode for thousands of years. Indeed, there are even some stars which explode once （59） ______ two weeks.
There are other old stars which do not die slowly, but are （60） ______ destroyed by one great explosion. These are known （61） ______ "supernovae". The explosion of a supernova is equivalent （62） ______ about a million hydrogen bombs going off at the same time. Just before the explosion the star's density becomes very great and it spins at a very high speed. A matchbox of materials taken from the star at that time would weigh about 1,000 tons, and the star （63） ______ be turning at about 16,000,000 kilometers per hour. The explosion itself occurs （64） ______, in the interval of a minute, but the supernova continues to shine long （65） ______ the event. One supernova which Chinese astronomers observed in 1054 can still be seen by us today. It has been shining for at least nine hundred years.
51. A. right B. reasonable C. sound D. wrong
52. A. after B. before C. during D. for
53. A. disappear B. lost C. missed D. exploded
54. A. old B. evil C. new D. dying
55. A. When B. While C. After D. As
56. A. in B. at C. with D. on
57. A. invisible B. brilliant C. visible D. noticeable
58. A. consume B. cost C. spend D. lose
59. A. every B. each C. at D. within
60. A. partly B. completely C. clearly D. instantly
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