首页
登录
职称英语
【B1】 [br] 【B6】 [originaltext]The origin of Earth’s moon, the largest moon in the
【B1】 [br] 【B6】 [originaltext]The origin of Earth’s moon, the largest moon in the
游客
2024-02-14
14
管理
问题
【B1】 [br] 【B6】
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
similarity
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3448854.html
相关试题推荐
[originaltext]Chrisisinchargeofpurchasingandmaintainingequipmentin
[originaltext]Chrisisinchargeofpurchasingandmaintainingequipmentin
[originaltext]Bowsandarrowsareoneoftheman’soldestweapons.Theygav
[originaltext]Bowsandarrowsareoneoftheman’soldestweapons.Theygav
[originaltext]M:Right,let’sgetontothemarketingstrategy.W:Well,thema
[originaltext]M:Right,let’sgetontothemarketingstrategy.W:Well,thema
[originaltext]M:Right,let’sgetontothemarketingstrategy.W:Well,thema
[originaltext]W:Tonyisthebestcross-countryrunnerwe’veeverhadinthiss
[originaltext]W:Tonyisthebestcross-countryrunnerwe’veeverhadinthiss
[originaltext]Sportsmadgamesareveryusefulforcharactertraining.Int
随机试题
TheodoreDreisersetforthhis______conceptoftheAmericansocietyinhisear
Xenonhasanumberofapplications,______itsuseinflashlampsforhighspeedp
Theboxmatchwillbebroadcast______ontelevisionandradiotoalloverthew
PASSAGEONE[br]What’sthefiercestcompetitionamongthecountriesaspiringfo
Peoplewhosufferfromalcoholabusehaveaphysicaldependenceonalcohol.[br]
肝脏是体内最大的腺体,属于消化腺。()
暂停作业时,对吊装作业中未形成稳定体系的部分,必须采取临时固定措施。
按照韦氏智商分级标准,IQ值在110~119之间属于()。单选(A)平常 (
根据我国《公司法》,下列职权中不属于有限责任公司董事会的是()A.执行股东会的
A.室间隔缺损 B.房间隔缺损 C.动脉导管未闭 D.法洛四联症 E.艾
最新回复
(
0
)