Astronomers studying a certain kind of supernova (exploding star) were surpr

游客2024-01-10  17

问题     Astronomers studying a certain kind of supernova (exploding star) were surprised to find the supernovas were fainter than expected. Seeking explanations, they discounted the possibility that cosmic dust might be screening out some of the light, because it would filter out blue light more than red, causing the supernovas to appear redder than they really are. Also, unless spread very smoothly throughout space, the dust would introduce large variations in the measurements. Another possibility is gravitational lensing, the bending of light rays as they skirt galaxies enroute. Such lensing occasionally causes brightening, but most often it contributes to the dimness of distant supernovas. Calculations show, however, that this effect becomes important only for sources more distant than the supernovas studied. [br] The passage implies which of the following about the measurements made by the astronomers?

选项 A、There were small calculation errors in their measurements.
B、There were no large variations in their measurements.
C、Their measurements were skewed by unevenly spread cosmic dust
D、Their measurements were incomplete because cosmos dust screened out some of the light.
E、It was possible to take more measurements of red light than of blue light.

答案 B

解析 第三句是虚拟语气,与现实相反。这句话的字面含义是“测量结果发生很大的变化”,因此现实中,这种测量结果的变化不大,所以选项B正确。
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