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
Light Night, Dark Stars Thousands of people around the globe step outside to gaze at their night sky. On a clear night, with
Light Night, Dark Stars Thousands of people around the globe step outside to gaze at their night sky. On a clear night, with
admin
2013-10-25
75
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 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, you’ve witnessed light pollution. It occurs when light from streetlights, office buildings, signs, and other sources streams into space and illuminates the night sky. This haze 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 will 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 development is increasingly obscuring the faint 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 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 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.
Why does the writer think growing cities affect astronomers’ work?
选项
A、Because the once dark rural areas are polluted by lights.
B、Because they can still see stars in rural areas.
C、Because rural areas are not a good place for astronomers to study stars.
D、Because faint light given off by stars can still be seen on a clear night.
答案
A
解析
题意:为什么作者认为城市规模的扩大会影响天文学家们的工作?答案在第五段中可以找到。随着城市规模的扩大,曾经昏暗的乡村逐渐变成了市郊,那里的灯火使科学家无法观测到星体发出的微弱光芒,故本题选A。
转载请注明原文地址:https://kaotiyun.com/show/wHmd777K
本试题收录于:
职称英语卫生类B级题库职称英语分类
0
职称英语卫生类B级
职称英语
相关试题推荐
Readthefollowingpassageandanswerquestions9-18.1.Peoplehavebeenpaintingpicturesforatleast30,000years.Theearli
Readthefollowingpassageandanswerquestions9-18.1.Mostyoungpeopleenjoysomeformsofphysicalactivity.Itmaybewalk
Readthefollowingpassageandanswerquestions9-18.1.Mostyoungpeopleenjoysomeformsofphysicalactivity.Itmaybewalk
Youwillhearfivepeoplegivingtheiropinionsonchanginginlife.Forquestions9-13,choosefromthelistA~Fwhateach
Youwillhearfivepeoplegivingtheiropinionsonchanginginlife.Forquestions9-13,choosefromthelistA~Fwhateach
Youwillhearfivepeopletalkingabouttheshortcoursestheyattended.Forquestions9-13,choosefromthelistA-Fwhate
Youwillhearfivepeopletalkingabouttheshortcoursestheyattended.Forquestions9-13,choosefromthelistA-Fwhate
Youwillhearfivepeopletalkingabouttheshortcoursestheyattended.Forquestions9-13,choosefromthelistA-Fwhate
随机试题
通过定量方法进行风险评价的作用表现在()。
银行的表内外资产可以分为银行账户和交易账户两大类。以下关于交易账户的说法中,错误的是()。
经济生活中的假冒伪劣、欺骗欺诈等缺诚失信现象屡禁不止,成为我国经济发展的严重障碍。()
2012年8月6日,国务院发布了《节能减排“十二五”规划》,《规划》指出,要以邓小平理论和“三个代表”重要思想为指导,深入贯彻落实科学发展观,坚持大幅降低能源消耗强度、显著减少主要污染物排放总量、合理控制能源消费总量相结合,形成加快转变经济发展方式的倒逼机
注册会计师在审计A公司2009年度财务报表时发现固定资产的以下项目,其中不应通过“固定资产清理”科目核算的有()。
生命是一场充满意外收获的伟大______,看上去难以掌握,其实______无处不在。填入划横线部分最恰当的一项是()。
提出管理遵循对事不对人的原则的管理家是()
Fearsofdeatharenotsoextensiveasmightbesupposed.Inapublicopinionpollof1500adults,onlyabout4percentshowede
NinetypercentofAmericansknowthatmostoftheircompatriotsareoverweight,butjust40percentbelievethemselvestobetoo
隐含回购利率最高的债券是最便宜可交割债券。()
最新回复
(
0
)