100Test－大学英语三级考试考前辅导练习十七

文章作者 100test 发表时间 2007:05:02 14:25:20
来源 100Test.Com百考试题网

Passage 13

Astronomers say they have found a Jupiter-like body circling a distant star in a planetary system like ours, an intriguing（引人兴趣的）discovery that raises the prospect of someday finding a planet resembling Earth.
Hugh Jones of the UK’s John Moores University in Liverpool said last week his team had discovered the system, illuminated by a star, some 94 light years from Earth. (a light year is the distance light travels in a year in a vacuum, about 9.3 trillion kilometers)
The star is similar to the Sun in structure and brightness and appears to be about the same age, Jones said. The planet is traveling around the star in an orbital path similar in shape and distance to the one that Jupiter follows around our Sun.
Those similarities have led Jones’ team of British, Australian and American scientists to conclude that they have come upon the possibility of finding another Earth in the Milky Way galaxy（银河系）.
Nearly 110 extra-solar planets----planets orbiting stars other than the Sun----have been found in the past decade, but this is the first one really like our own solar system, according to a London researcher.
No large planets have been found between the Jupiter-like planet and the star, allowing scientists to conclude than an Earth-sized planet could be found in between.
The discovery was found by measuring the star’s movement caused by the gravity of the planet. The technique measures the very slight moves of a central star and then uses the magnitude of this motion to determine the presence of orbiting planets, the size and shape of their orbits and their mass. The technique works only for larger planets and cannot detect those much smaller.
Most extra-solar planets had elliptical(椭圆的) orbits, and only a handful of the planet discovered so far follow the nearly circular orbit of our solar system.

1. The scientists concluded that it is possible to _____________.

A. find a Jupiter-like body in the Milky Way Galaxy

B. find a planet having circular orbit

C. find an Earth-like planet in the Milky Way Galaxy

D. find a distant star in solar system

2. The word “ours” in paragraph 1 most probably refers to _________.

A. the Milky Way Galaxy

B. the earth

C. the sun

D. the solar system

3. This Jupiter-like body’s orbit must be ________.

A. elliptical

B. nearly round

C. flat

D. not mentioned in the passage

4. The star which the Jupiter-like body revolves around __________.

A. is similar to our Earth in orbit

B. has the Sun’s shape

C. didn’t appear until recently

D. is not so bright as the Sun

5. Why do scientists consider this discovery intriguing?

A. This is the first time we’ve found a extra-solar planet.

B. This is the first time we’ve found a planet having circular orbit

C. This is the first time we’ve found a Jupiter-like body.

D. This is the first time we’ve found an extra-solar system like our own