首页
财务会计
医药卫生
金融经济
考公考编
外语考试
学历提升
职称考试
建筑工程
IT考试
其他
登录
职称考试
Light Night,Dark Stars Thousands of people around the globe step outside t...
Light Night,Dark Stars Thousands of people around the globe step outside t...
admin
2020-12-24
0
问题
Light Night,Dark Stars
Thousands of people around the globe step outside to gaze at their night sky. On a clear night, with no clouds, moonlight, or artificial lights to block the view, people can see more than 14,000 stars in the sky,says Dennis Ward,an astronomer (天文学家)with the
University Corporation for Atmospheric Research (UCAR) in Boulder, Colo. But when people are surrounded by city lights, he says, they’re lucky to see 150 stars.
If you’ve ever driven toward a big city at night and seen its glow from a great distance, youVe witnessed light pollution. It occurs when light from streetlights, office buildings, signs, and other sources streams into space and illuminates (照亮)the night sky. This
haze (薄雾)of light makes many stars invisible to people on Earth. Even at night,big cities like New York glow from light pollution, making stargazing difficult.
Dust and particles of pollution from factories and industries worsen the effects of light pollution. “ If one city has a lot more light pollution than another,” Ward says, “ that city wHI suffer the effects of light pollution on a much greater scale. ’’
Hazy skies also make it far more difficult for astronomers to do their jobs. Cities are getting larger. Suburbs are growing in once dark, rural areas. Light from all this new developmentis increasingly obscuring (使变模糊)the faint (微弱的)light given off by distant stars. And if scientists can,t locate these objects,they can,t learn more about them.
Light pollution doesn’t only affect star visibility. It can harm wildlife too. It’s clear that artificial light can attract animals, making them go off course. There’s increasing evidence, for example, that migrating (迁徙)birds use sunsets and sunrises to help find their way, says Sydney Gauthreaux Jr.,a scientist at Clemson University in South Carolina. “ When light occurs at night,” he says,“ it has a very disruptive (破坏性的) influence”. Sometimes birds fly into lighted towers, high-rises, and cables from radio and television towers. Experts
estimate that millions of birds die this way every year.
On a clear night,people can see
选项
A 150 stars.
B hundreds of stars.
C 0ne thousand stars.
D more than 14,000 stars.
答案
D
解析
转载请注明原文地址:https://ti.zuoweng.com/ti/IbsQKKKQ
相关试题推荐
MilkDrinking Peopleeverywheredrinkmilk.Mostpeopledrinkcows'milk....
DifferentMeaningsofColors Thefactthatblindpeoplecan"see"things...
Aftersupperweusuallytakeastrollaroundtheparkforaboutanhour.()A.walk
Thcfoodisinadequatefortenpeople.(2007年真题)()A.demandedB.qualifiedC.insuff
Alotofpeoplecouldfallillafterdrinkingcontaminatedwater.(2004年真题)()A.mu
Thefoodisinadequatefortenpeople.A.demandedB.qualifiedC.insufficientD
共用题干 TheSandwichGenerationTodaypeopleoftenlookforwardtotheirmiddle...
共用题干 TheSandwichGenerationTodaypeopleoftenlookforwardtotheirmiddle...
共用题干 TheSandwichGenerationTodaypeopleoftenlookforwardtotheirmiddle...
共用题干 TheSandwichGenerationTodaypeopleoftenlookforwardtotheirmiddle...
随机试题
HowshouldMr.BrowngiveSaveTheYouthh
中国银监会于2011年出台了《商业银行贷款损失准备管理办法》,设立了()来考核
灯具的支撑悬吊装置有()。
根据文章,下列说法正确的是:
所有者权益是投资人对企业全部资产的所有权。( )
某待估宗地的剩余使用年限为30年,还原利率为6%,比较实例价格为3000元/平方
不是企业组织结构变革前兆的是()。
从境外房地产经纪行业的情况看,( )的房地产经纪行业管理是一种惯例。A、高效化B、科技化C、专业化D、网络化
供应商认为采购商的采购业务对他们来说无关紧要,但该采购业务对本单位却是十分重要的,这样的供应商属于()的供应商。A:重点商业型B:伙伴型C:商业型D:优先
当事人订立合同,应当采取要约、承诺方式。()