首页
登录
职称英语
The sun today is a yellow dwarf star. It is fueled by thermonuclear reaction
The sun today is a yellow dwarf star. It is fueled by thermonuclear reaction
游客
2023-12-27
44
管理
问题
The sun today is a yellow dwarf star. It is fueled by thermonuclear reactions near its center that convert hydrogen to helium. The sun has existed in its present state for about 4 billion, 600 million years and is thousands of times larger than the Earth.
By studying other stars, astronomers can predict what the rest of the sun’s life will be like. About 5 billion years from now, the core of the sun will shrink and become hotter. The surface temperature will fail. The higher temperature of the center will increase the rate of thermonuclear reactions. The outer regions of the sun will expand approximately 35 million miles, about the distance to mercury, which is the closest planet to the sun. The sun will then be a red giant star. Temperatures on the earth will become too hot for life to exist.
Once the sun has used up its thermonuclear energy as a red giant, it will begin to shrink. After it shrinks to the size of the earth, it will become a white dwarf star. The sun may throw off huge amounts of gases in violent eruptions called nova explosions as it changes from a red giant to a white dwarf.
After billions of years as a white dwarf, the Sun will have used up all its fuel and will have lost its heat. Such a star is called a black dwarf. After the Sun has become a black dwarf, the earth will be dark and cold. If any atmosphere remains there, it will have frozen onto the earth’s surface. [br] What will probably be the first stage of change as the sun becomes a red giant?
选项
A、Its core will cool off and use less fuel.
B、Its surface will become hotter and shrink.
C、It will use up its thermonuclear energy.
D、Its center will grow smaller and hotter.
答案
D
解析
细节题型见第二段第二句并参照注释51:距今大约五十亿年后,太阳的核会缩小并且会变得更热,而太阳表面的温度会降低,然后太阳将会成为一个红色的巨星;因此D为答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3311091.html
相关试题推荐
Theskyhadaneerieyellow-orangehue,withthesunglowingbehindapeculiarh
Thesuntodayisayellowdwarfstar.Itisfueledbythermonuclearreaction
Thesuntodayisayellowdwarfstar.Itisfueledbythermonuclearreaction
Thesuntodayisayellowdwarfstar.Itisfueledbythermonuclearreaction
Thesuntodayisayellowdwarfstar.Itisfueledbythermonuclearreaction
Thesuntodayisayellowdwarfstar.Itisfueledbythermonuclearreaction
Amanwasplayingapianobeingpaintedpurpleandyellowandleftthereforthi
Kaganmaintainsthataninfant’sreactionstoitsfirststressfulexperiencesar
Amanwasplayingapianobeingpaintedpurpleandyellowandleftthereforthi
Thereactionwasinstantandoverwhelming.Socialmediaexploded,radiophone-in
随机试题
[originaltext]Amobileofficeis,quiteliterally,anofficewhichiscapab
With950millionpeople,IndiarankssecondtoChinaamongthemostpopulous
A.whereB.exceptionsC.affairsD.meetE.cracksonF.cracksupG.r
AwomaninGuangzhouwasbittenbyherpetafterataxistruckthedogatacros
Whilethe1970spoppsychotherapymovementfocusedontheimportanceoflett
下列关于消防水泵房的叙述有错的是( )。A.独立设置的消防水泵房,其耐火等级必
以下选项中,()为螺杆式制冷压缩机的供油方式。A.润滑油喷射润滑 B.压力
常见引起肾前性肾衰竭的病因是A.肝门静脉高压症致食管曲张静脉破裂 B.高血压肾
AstartupcompanyinCaliforniaisusing
随着我国城市建设的快速发展,为保证新建或在役供水和供气管道的安全运行,降低或消除
最新回复
(
0
)