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TOEFL Directory > TOEFL writing > TOEFL Reading Class Unit 2_Passage 9_Question 89-99
TOEFL Reading Class Unit 2_Passage 9_Question 89-99
You have about 15 minutes to finish this passage.
First,use about 3-4 minutes to read the passage, try to understand the main idea of this passage.
Don't read it so slowly or try to remember all details.You need to do "fast reading",and "scan" the passage.
Second, read questions 1-11, and with questions you go back the passage again and look for correct answers.
Question 89-99
Passge 9
The closest a large asteroid has come to flying by Earth occurred on March 22, 1989, when asteroid 1989 FC came within 430,000 miles of our planet. Astronomers did not detect asteroid 1989 FC until it was already moving away from Earth. Only then did they notice a dramatic decrease in the asteroid's motion against background stars. The astronomers failed to notice the approach, which must have been on a near-grazing trajectory, because it came from the direction of the Sun. Also, the Moon was nearly full, further hampering observations.
The asteroid was about half a mile wide, and though a collision with Earth would have been catastrophic, a fluke of orbital geometry might have lessened the impact a little. The asteroid orbits the Sun in the same direction and at almost the same speed as Earth, completing a revolution in about one year. Therefore, its approach was rather slow compared to other celestial objects. However, because of Earth's large size, the planet's gravitational pull would have accelerated the asteroid during its final approach. If a collision had occurred, the asteroid would have produced a crater five to ten miles wide.
Asteroid 1989 FC is one of only thirty similar bodies that are capable of approaching Earth. In addition, several hundred to one thousand or more asteroids wider than one-third of a mile are capable of crossing Earth's orbit for a close encounter. For example, on December 8, 1992, a large asteroid called Toutatis, which measured 2.5 miles long by 1.6 miles wide, flew within 2.2 million miles of Earth.
Not one of the close encounters had been anticipated by astronomers. To avoid the danger of an asteroid collision, the threatening body would firsthave to be tracked by telescopes and radar and its course plotted accurately so its orbit could be determined precisely. If an asteroid were found to be on a collision course with Earth, astronomers could provide timely warnings. The rogue asteroid might then be nudged out of its Earth-bound trajectory by use of explosive devices.
89. Which of the following subjects does the passage mainly discuss?
a) How scientists predict the course of asteroids
b) A comparison of asteroid 1989 FC and asteroid Toutatis
c) The effects of an asteroid's collision with Earth
d) Asteroids that closely approach Earth
90. According to the passage, which of the following is true of asteroid 1989 FC ?
a) It is the largest asteroid ever recorded.
b) It travels at a slower speed than Earth.
c) It missed hitting Earth by less than 430,000 miles.
d) Its approach toward Earth was observed by astronomers.
91.
92. The word hampering in the passage is closest in meaning to
a) providing
b) lowering
c) restricting
d) assisting
93.
94. The word accelerated in the passage is closest in meaning to
a) speeded up
b) separated into
c) guided toward
d) attracted to
95. The author mentions asteroid Toutatis in paragraph 3 as an example of a large asteroid that
a) collided with Earth
b) approached Earth at the same time as asteroid 1989 FC
c) travels faster than Earth
d) crossed Earth's orbit
96. Which of the following statements about close encounters between Earth and the asteroids mentioned in the passage is true?
a) They were not predicted by astronomers.
b) They involved tiny asteroids.
c) They were hidden from view by sunlight.
d) They typically occur once every three years.
97.
98. The paragraph below is a summary of the passage. Click on the sentence in the paragraph that should NOT be included in the summary.
ⒶThe asteroid to most closely approach Earth in recorded history was 1989 FC. ⒷThere may be over one thousand asteroids that are similar in size to asteroid 1989 FC. ⒸThe most accurate way to measure the size of an asteroid is to observe its passage in front of a star. ⒹTracking asteroids and calculating orbits would possibly allow astronomers to prevent their collisions with Earth.
99.
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