题目内容
请将标有A~G的段落插入文章中标号1~5的合适位置,使这篇文章意义完整,结构连贯;其中有的段落是多余的。
Goodbye Pluto
It is always hard for a small fish to live in a big pond.Pluto’s recent departure from the classical planet family clearly proves that size really matters.
1
After weeks of heated debate, over 2, 500 astronomers from 75 countries voted on the definition of a “planet” at a conference of the International Astronomical Union(IAU). 2 It is all because, compared with Neptune, Pluto is very small.It is attracted by Neptune’s gravity when the two planets get closer.
According to IAU, a “dwarf planet” should have an orbit around the Sun. 3 .
The solar system is now made up of the eight “classical planets, ” together with a number of dwarf planets.The classical planets are:Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
The debate over Pluto’s status started in 1992.After an advanced telescope was sent into space, astronomers started to find a belt of objects, which lies beyond Neptune.The belt contains nearly 1, 000 objects, including Pluto. 4 There are at least two objects of a similar size to Pluto.
5 More dwarf planets of a similar size to Pluto would join the family of planets.Scientists will probably find many more dwarf planets.
A.It will not have a clear neighborhood around its orbit, and must not be a satellite.The new classification means that the science textbooks will have to be updated.
B.Astronomers voted on August 24 to create the first scientific definition of the word “planet”, and Pluto obviously didn’t make the cut.It turned out to be only a “dwarf planet”.
C.It seems that even if the IAU had kept Pluto’s status as a planet, the classical theory of nine planets in the solar system would have had to be changed, but the other way around.
D.Pluto will be cut away for ever.
E.As they continued the exploration, scientists recently discovered at least 41 dwarf planets at the edges of the solar system.
F.According to the definition, a planet must have a clear neighborhood around its orbit.Pluto has widely been considered a planet since its discovery in 1930.Unfortunately, it has a special orbit which overlaps with Neptune’s.
G.Spaceships will be sent onto Pluto.
解析:
B F A E C |
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