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
2023-11-11
55
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 has no water.
B、The Moon contains almost no iron.
C、Thy Moon is the largest moon in the solar system.
D、The Moon does not have a molten core.
答案
B
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3178002.html
相关试题推荐
WhatledtothefailureofNASA’smission?[br][originaltext]NASA’sfirst
WheredidCindygetherinformationabout"smart"cars?[originaltext]M:I’msor
Wheredoestheconversationtakeplace?[br][originaltext]M:Hi,Linda.W:Hi,
PaulWolfowitzhasbeeninvolvedina______.[originaltext]Thekeycommitt
Mr.WarrenChristopher[originaltext]SecretaryofStateWarrenChristopher
WhichofthefollowingisNOTtrueaboutLiverpool?[br][originaltext]In
WhichofthefollowingisNOTtrueaboutLiverpool?[originaltext]Intheea
HowdidthemanspendhislastdayinLondon?[br][originaltext]Ihadspen
HowdidthemanspendhislastdayinLondon?[br][originaltext]Ihadspen
Janethaseventuallydecidedtogoona[br][originaltext]M:I’mlongingtohe
随机试题
Ifyouweretotape-recordoneofDavidLetterman’scomedyroutines,memoriz
D
官府菜讲究()和筵席名目繁多且用餐环境古朴高贵A.用料广博益寿 B.制作奇巧精
不良资产业务是指金融资产管理公司根据市场原则购买转让方的不良资产,并通过资产转让
城市燃气管网中( )是指具有中压和低压两个压力级制的城市地下管网系统。A.一级
正确发挥意识能动作用最基本的前提是()。 a.积极性的充分调动 b.集体智
某公安局以张某倒卖黄金为由,根据《金银管理条例》的规定,作出没收倒卖黄金款200
钢板桩可用()等方法下沉。A.锤击 B.振动 C.射水 D.顶推
男性,35岁。左上腹被拖拉机撞伤后钝痛1天,突发左上腹剧痛3小时。查体:P140
在建筑工程施工过程中,隐蔽工程在隐蔽前应通知()进行验收,并形成验收文件。
最新回复
(
0
)