To understand how astrology works, we should first take a quick look at the sky. Although the stars are at enormous distances, t

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问题      To understand how astrology works, we should first take a quick look at the sky. Although the stars are at enormous distances, they do indeed give the impression of being affixed to the inner surface of a great hollow sphere surrounding the earth. Ancient people, in fact, literally believed in the existence of such a celestial sphere. As the earth spins on its axis, the celestial sphere appears to turn about us each day, pivoting at points on a line with the earth’s axis of rotation. This daily turning of the sphere carries the stars around the sky, causing most of them to rise and set, but they, and constellations they define, maintains fixed patterns on the sphere, just as the continent of Australian maintains its shape on a spinning globe of the earth. Thus the stars were called fixed stars.
    The motion of the sun along the ecliptic is, of course, merely a reflection of the revolution of the earth around the sun, but the ancients believed the earth was fixed and the sun had and independent motion of its own, eastward among the stars. The glare of sunlight hides the stars in daytime, but the ancients were aware that the stars were up there even at night, and the slow eastward motion of the sun around the sky, at the rate of about thirty degrees each month, caused different stars to be visible at night at different times of the year.
     The moon, revolving around the earth each month, also has an independent motion in the sky. The moon, however, changes it position relatively rapidly. Although it appears to rise and set each day, as does nearly everything else in the sky, we can see the moon changing position during as short an interval as an hour or so. The moon’s path around the earth lies nearly in the same plane as the earth’s path around the sun, so the moon is never seen very far from the ecliptic in the sky. There are five other objects visible to the naked eye that also appear to move in respect to the fixed background of stars on the celestial sphere. These are the planets Mercury, Venus, Mars, Jupiter, and the Saturn. All of them revolve around the sun in nearly the same plane as the earth does, so they, like the moon, always appear near the ecliptic. Because we see the planets from the moving earth, however, they behave in a complicated way, with their apparent motions on the celestial sphere reflecting both their own independent motions around the sun and our motion as well.
Which of the following is true about the motion of the moon?

选项 A、The moon and the sun are moving in the same plane.
B、The moon revolved along the ecliptic.
C、The moon moves faster than the sun.
D、The position of the moon can be found changed in an hour’s time.

答案D

解析 根据第三段的第二句和第三句话,文中说月亮的位置变化相对而言比较快,尽管看起来每天起起落落,事实上它的运动间歇为一个小时。由此可以肯定D为正确答案。
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