首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
How many things can you see in the night sky? A lot! On a clear night you might see the Moon, some planets,and thousands of spar
How many things can you see in the night sky? A lot! On a clear night you might see the Moon, some planets,and thousands of spar
admin
2015-01-09
49
问题
How many things can you see in the night sky? A lot! On a clear night you might see the Moon, some planets,and thousands of sparkling stars.
You can see even more with a telescope. You might see stars where before you only saw dark space. You might see that many stars look larger than others. You might see that some stars that look white are really red or blue. With bigger and bigger telescopes you can see more and more objects in the sky. And you can see those objects in more and more details.
But scientists believe there are some things in the sky that we will never see. We won’t see them with the biggest telescope in the world, on the clearest night of the year. That’s because they’re invisible. They’re the mysterious dead stars called black holes.
You might find it hard to imagine that stars die. After all,our Sun is a star. Year after year we see it up in the sky burning brightly,giving us heat and light. The Sun certainly doesn’t seem to be getting old or weak. But stars do burn out and die after billions of years.
As a star’s gases burn,they give off light and heat. But when the gas runs out,the star stops burning and begins to die.
As the star cools,the outer layers of the star pull in toward the center. The star squashes into a smaller and smaller ball. If the star was very small, the star ends up as a cold, dark ball called a black dwarf. If the star was very big.it keeps squashing inward until it’s packed together tighter than anything in the universe.
Imagine if the each were crushed until it was the size of a tiny marble. That’s how tightly this dead star, a black hole is packed. What pulls the star in toward its center with such power? It’s the same force that pulls you down when you jump—the force called gravity. A black hole is so tightly packed that its gravity sucks in everything—even light. The light from black hole can never come back to your eyes. That’s why you see nothing but blackness.
So the next time you stare up at the night sky,remember: there’s more in the sky than meets the eyes! Scattered in the silent darkness are black holes—the great mystery of space.
What is the main idea of the article?
选项
A、The future of our Sun billions of years from now.
B、The difference between our Sun and a dead star.
C、The mystery of black holes in the universe.
D、The sparkling and dying stars in the sky.
答案
C
解析
题目问:文章的主要观点是什么?通过文章内容可知,文章主要是向读者在介绍黑洞的相关知识。包括黑洞是如何形成的,黑洞的特点等等。所以。答案是C。
转载请注明原文地址:https://kaotiyun.com/show/YBLO777K
0
考博英语
相关试题推荐
TheAssociationofUniversityTeachersclaimsthattaxpayers’money,______forbasicresearch,isbeingusedtopropupindustri
Onereasonpeoplebelievephysician-assistedsuicideshouldbeavailableforthosewhorequestit,isthatpeoplefeartheloss
Thejobsofwildlifetechniciansandbiologistsseemed______tohim,butonedayhediscoveredtheirdifference.
Ifitwereonlynecessarytodecidewhethertoteachelementarysciencetoeveryoneonamassbasisortofindthegiftedfewan
StandardEnglishisthevarietyofEnglishwhichisusuallyusedinprintandwhichisnormallytaughtinschoolsandtonon-nat
Ifyousmokeandyoustilldon’tbelievethatthere’sadefinitebetweensmokingandbronchialtroubles,heartdiseaseandlung
Optimismandpessimismarebothpowerfulforces,andeachofusmustchoosewhichwewanttoshapeouroutlookandourexpectati
Thereisacloserrelationshipbetweenmoralsandarchitectureandinteriordecoration【C1】______wesuspect.Huxleyhaspointedo
ReadthefollowingpassagecarefullyandthenexplaininyourownEnglishtheexactmeaningofthenumberedandunderlinedparts
AnabandonedairfieldnearaformerNaziconcentrationtrampmaysoonfeaturepagodasandTaiChiparks.A$700millionproject
随机试题
简述仲裁的特点。
病人因受寒而哮喘发作,呼吸急促,喉中哮鸣,如水鸡声,咳嗽,胸膈满闷,痰少咯吐不爽,形寒怕冷,口不渴,舌苔白滑,脉象浮紧,主方选
某单位98名正常成年女子的血清总胆固醇(mmol/L)频数分布如下:该资料宜绘制成
为成人患者插鼻饲管时,当鼻饲管插入()时应嘱咐患者做吞咽动作,将鼻饲管迅速插入胃内。
陈某自2000年1月起开始在火车站倒卖车票,至次年7月止。2002年4月,公安机关根据举报发现了陈某的违法行为。以下哪一种说法是正确的?()
下列各项不属于证券登记结算公司业务的是( )。
甲公司从证券市场购入股票20000股,每股10元,其中包含已宣告但尚未领取的每股股利0.6元,另支付交易费用1000元。企业将其划分为交易性金融资产核算,则其初始入账价值是()元。
常常被称为国家和民族的“胎记”,是一个民族得以延续的“精神基因”,是培养民族心理、民族个性、民族精神的“摇篮”,是民族凝聚力的重要基础的是()
Women’smindsworkdifferentlyfrommen.Atleast,thatiswhat(1)______mostmenareconvincedof.Psychologistsviewthesubj
Whatistheprojectmainlyconcernedwith?
最新回复
(
0
)