首页
登录
职称英语
【B1】 [br] 【B5】 [originaltext]The origin of Earth’s moon, the largest moon in the
【B1】 [br] 【B5】 [originaltext]The origin of Earth’s moon, the largest moon in the
游客
2023-07-13
54
管理
问题
【B1】 [br] 【B5】
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 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 in formation, 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
答案
Composed
解析
转载请注明原文地址:http://tihaiku.com/zcyy/2832587.html
相关试题推荐
[originaltext]MyfirstsemesterofcollegewastheworstI’vebeenthrough.
[originaltext]MyfirstsemesterofcollegewastheworstI’vebeenthrough.
[originaltext]MyfirstsemesterofcollegewastheworstI’vebeenthrough.
[originaltext]Bookswhichgiveinstructionsonhowtodothingsareverypo
[originaltext]M:Howdidthejobinterviewgothismorning?W:I’mquiteconfid
[originaltext]M:Howdidthejobinterviewgothismorning?W:I’mquiteconfid
[originaltext]M:Howdidthejobinterviewgothismorning?W:I’mquiteconfid
[originaltext]M:Howdidthejobinterviewgothismorning?W:I’mquiteconfid
[originaltext]M:Howdidthejobinterviewgothismorning?W:I’mquiteconfid
【B1】[br]【B11】[originaltext]Catsarecreaturesofhabit.Theyliketogot
随机试题
ManyofChina’splansinEuropearejustwhatyouwouldexpectofariseneconom
[originaltext]M:Hi,Ruby,haveyouheardthatthereisgoingtobearobotsho
解构主义设计将观念中固定化的“结构模式”打散组合,希望通过新的排列组合产生一种“
长期以来,猕猴乃至人类以外的其他灵长类动物说不了“人话”,有人推测这与它们的声带
事业单位的净资产是指资产减去()的差额。A.支出 B.负债 C."收入
善于疏肝破气,消积化滞的药物是A.青皮 B.香附 C.沉香 D.檀香 E
“建国君民,教学为先”这句话反映了( )。A.教育与政治的关系 B.教育
教育费附加是随( )附加征收。A.印花税 B.所得税 C.增值税 D.房
1928年,南京国民政府发表“改订新约”的对外宣言后,首先与中国签订关税条约的国
患者,男,27岁,主诉:牙龈疼痛、出血,口腔腐臭,不敢刷牙3天,无发热。该患者牙
最新回复
(
0
)