On a good night when there is no Moon and the air is clear, only up to 4,000 or so stars can be seen by the unaided eye. From ancient times star – watchers have tried to bring some order into the sky by fitting the stars into patterns. The constellations (星座) to which names were given.
Observation of the night sky every few hours shows that in the northern hemisphere(半球) the stars appear to turn anticlockwise (逆時針方向) about a point near the Pole Star. As they turn, the stars keep the same positions in relation to each other, and in fact the appearance of the constellations has changed very little over the centuries. Like the Sun and Moon, the stars have a daily journey across the sky, rising upwards in the east and setting in the west – due to the Earth’s daily spin. The Circumpolar Stars, those near the Pole Star, are an exception to this; they are so close to the pole that they never disappear below the horizon (地平線) Although the stars always rise in the same places they do not do so at the same time every day. They rise about 4 minutes earlier each day since the Earth is progressing in its orbit around the Sun; in almost but not exactly a year they again rise and set at the same time. If a certain star is seen to rise in the east exactly when the Sun sets on a particular day, a few weeks later it will be seen well above the eastern horizon at sunset.
58.Which do you think is the best title of the passage above?
A.The Earth, the Moon and the Stars. B.Motion of the Stars.
C.How to Watch the Stars. D.Appearance of the Stars.
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