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
65
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.
Which of the following statements is NOT a fact?
选项
A、Black holes are dead stars.
B、Black holes have gravity.
C、Black holes are invisible.
D、There is nothing as mysterious as a black hole.
答案
D
解析
题目问:下列哪项不是事实?“They’re the mysterious dead stars called black holes.通过这句话可知,黑洞是死的星星。What pulls the star in toward its center with such power?It’s the same force thatpulls you down when you jump—the force called gravity.”通过这句话可知,黑洞有重力。“That’s be-cause they’re invisible.”通过这句话可知,黑洞看不见。“Scattered in the silent darkness are blackholes--the great mystery of space.”通过这句话可知,黑洞是寂静宇宙中最神秘的。所以,答案是D。
转载请注明原文地址:https://kaotiyun.com/show/4BLO777K
0
考博英语
相关试题推荐
GregGadson,alieutenantcolonelintheArmy’sWarriorTransitionBrigade,isanaturalleader—thekindofguyyou’dbelooking
Theprincipleofthesocialcharacteroftheschoolasthebasicfactorinthemoraleducationgivenmaybealsoappliedtothe
MerchantRobertMorriswasamanofmanydistinctions,oneofthewealthiestindividualsintheColoniesandaneconomicwizard,
Parallelingthegrowthofinterestamongprofessionalhistoriansduringtheearly1960s,Ihadasimultaneous______ofpopularin
Peoplethinkingabouttheoriginoflanguageforthefirsttimeusuallyarriveattheconclusionthatitdevelopedgraduallyas
Sociologistsusethetermpowertorefertothecapacityofpeopleorgroupstocontrolorinfluencetheactionsofothers,whet
AlltherecentnewsonAIDSisbad.ThedeathofRockHudson【1】publicconcernaboutthe【2】almosttothepointofpanic.Nowgene
______moreimportant,notonlythelostcitieswererecovered,butthenewcitieswerebuilt.
AbudgetapprovedbytheEuropeanParliamentfortheEuropeanEconomicCommunitywasdeclaredadoptedTuesdaydespiteopposition
Ifyousmokeandyoustilldon’tbelievethatthere’sadefinitebetweensmokingandbronchialtroubles,heartdiseaseandlung
随机试题
男,16岁,贫血、黄疸7年。脾肋下2.8cm,Hb70g/L,网织红细胞0.10,白细胞和血小板计数正常。骨髓增生明显活跃,以红系增生为主,红细胞渗透脆性试验在0.70%盐水溶液中开始溶血。其父也有轻度贫血及黄疸。最有价值的治疗是
患者,男,75岁。7天前因胆囊多发小结石行腹腔镜胆囊切除术,近2日来发现巩膜黄染。(2009年)患者出现黄疸最可能的原因是
关于血栓闭塞性脉管炎的治疗,下列哪项是错误的
男性,52岁,自幼起咳嗽、咳痰、喘息,多为受凉后发作,静滴“青霉素”可缓解,10—20岁无发作,20岁后又有1次大发作,发作时大汗淋漓、全身发紫、端坐不能平卧,肺部可闻及哮鸣音,静脉推注“茶碱、地塞米松”完全缓解。自后反复出现夜间轻微喘息,每周发作3次以上
进行氧气雾化吸入时的正确方法是
患者女,20岁。四肢关节疼痛7个月,近2个月出现面颊部对称性红斑,反复发作口腔溃疡,诊断为“系统性红斑狼疮”。以下护理措施不妥当的是
下列关于保证人的说法,错误的是()。
实验社会心理学的奠基人是()。
基层群众性自治组织:是指我国依照宪法和法律有关规定,以城乡居民或村民一定居住地为纽带和范围设立的,并由居民或村民选举产生的成员组成的,实行自我管理、自我教育、自我服务的社会组织。依据上述定义,下列组织属于基层群众性自治组织()。
《先驱》
最新回复
(
0
)