首页
登录
职称英语
What is the talk mainly about? [br] [originaltext] The origin of Earth’s mo
What is the talk mainly about? [br] [originaltext] The origin of Earth’s mo
游客
2024-10-25
48
管理
问题
What is the talk mainly about? [br]
The origin of Earth’s moon, the largest moon in the solar system, is still something of a mystery. There are some theories about its origin however. Now, keep in mind that a theory of the moon’s origin has to be consistent with two important facts. The first fact is that the Earth contains a lot of iron, most of it has an iron core. But the moon contains practically no iron. The second fact is that other than the difference in iron content, the moon and Earth are composed of accentually the same minerals, a similarity not shared with any other planet or moon in our solar system.
One of the earliest theories of the moon’s origin, I called it the Capture Theory, proposes that the moon was somehow captured by Earth’s gravitational force. This theory is improbable, however, because it assumes that the moon and Earth formed in different parts of the solar system. If this was true you would expect the moon’s composition to be much different from Earth’s composition, just as all the other planets in the solar system are so different from Earth.
A second theory of the moon’s origin is more promising. It is sometimes referred to as the Mars Theory, because according to this theory, when Earth was still molten, it was struck by a planet about the size of Mars. The impact caused the cores of the two planets to melt together and chunks of Earth’s crust to be thrown out into space. These chunks came together to form the moon. Now, remember, Earth’s crust is low in iron, because the iron is in Earth’s core, but high in various other minerals. This then accounts for why there is little iron but lots of other minerals on the moon.
选项
A、The Moon formed from pieces of Earth’s crust.
B、The Moon was struck by another planet.
C、The Moon’s composition resembles that of Mars.
D、The Moon’s mineral content has changed over time.
答案
A
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3817274.html
相关试题推荐
Theaimoftheagreementisto______.[br][originaltext]TheCanadianpol
TowhomdidMs,Tanakatellaboutheridea?[br][originaltext]JapaneseFore
TowhomdidMs,Tanakatellaboutheridea?[originaltext]JapaneseForeignMi
Whohastakenstepstoresolvetheconflict?[br][originaltext]U.N.Securi
Whatisthetalkmainlyabout?[br][originaltext]TheoriginofEarth’smo
Whatisthetalkmainlyabout?[originaltext]TheoriginofEarth’smoon,th
WhatdoesthespeakersayabouttheroadbetweenMainandQuebec?[br][origin
WhatdoesthespeakersayabouttheroadbetweenMainandQuebec?[br][origin
WhatdoesthespeakersayabouttheroadbetweenMainandQuebec?[originaltext
Whyisthemantalkingtothewoman?[br][originaltext]W:I’msorry,butIcan
随机试题
JobstresshasbecomeacommonandcostlyproblemintheAmericanworkplace,l
Airpollutionexistsnotonlyoutdoor,butalsoindoor.Ithasgreateffectso
Theteacherdoesn’tpermit______inclass.A、smokeB、smokesC、tohaveasmokeD、s
It’sanannualback-to-schoolroutine.Onemorningyouwavegoodbye,andtha
在IP数据报中,片偏移字段表示本片数据在初始IP数据报数据区的位置,该偏
预算是战略执行的工具。()
工作场地应平坦坚实。在松软地面作业时,应在履带下铺设厚度在()以上的钢板,钢板
设数组a[1..n,1..m](n>1,m>1)中的元素以行为主序存放,每个元素
患者男,41岁。因饮酒诱发了急性胰腺炎急诊入院。 针对胰腺炎患者宜选用的止痛药
服务项目招标采购的流程中,刊登广告的下一程序是()。A、建议书的评审B、准备短
最新回复
(
0
)