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
Northern lights is the name of a light phenomenon often seen in the northern regions. The lights have been around since Earth fo
Northern lights is the name of a light phenomenon often seen in the northern regions. The lights have been around since Earth fo
admin
2014-01-07
25
问题
Northern lights is the name of a light phenomenon often seen in the northern regions. The lights have been around since Earth formed an atmosphere—the dinosaurs saw it, early humans saw it and our descendants will see it. The scientific name for the phenomenon is "Aurora Borealis", aurora for short.
An aurora is a sporadic, generally faint, atmospheric phenomenon usually seen in the night sky from locations at high latitudes. More commonly known as the "northern lights," it may first appear as a faint, milky glow low in the north, too dim for the human eye to detect any color but bright enough to silhouette clouds near the horizon. It may develop into steady greenish arcs or form glaring, swirling curtains of yellow-green light. During the most dramatic displays visible from regions at middle latitudes, such as central Europe and the United States, a crimson glow fills much of the sky. It was this form that inspired European scientists of the 1600s to call the phenomenon aurora borealis, literally "northern dawn," but it also occurs at high southern latitudes, where it is formally called aurora australis, "southern dawn." The same processes are at work in both hemispheres—not just on Earth, but on other planets as well—and today, scientists simply refer to this phenomenon as an aurora. The ghostly forms of an aurora include quiescent patches, veils, and arcs, and rapidly moving rays and curtains.
Many historical accounts of the northern lights from areas far south of its usual location exist. An early Chinese record describes it as a "red cloud spreading all over the sky." The Roman philosopher Seneca wrote that an aurora in A.D. 37 tricked the emperor into sending troops to aid what he thought was the burning seaport of Ostia, "when the glowing of the sky lasted through a great part of the night, shining dimly like a vast and smoking fire." In 1583, similar "fires in the air" mobilized thousands of French pilgrims, who prayed to avert the wrath of God. On September 15, 1839, an intense aurora dispatched firefighters throughout London.
What causes the showers of charged particles that create the northern lights? Ultimately, the source lies in the solar wind, a fast-moving stream of particles constantly flowing from the Sun that carries the Sun’s magnetic field out into space. The solar wind, typically moving at 250 miles(400 kilometers)per second, flows past Earth’s magnetic field and molds it into an elongated bubble or cavity, compressing its sunward side and stretching its night side far beyond the Moon’s orbit. Under certain conditions, the solar wind’s magnetic field can merge with Earth’s, creating electrical currents that drive protons and electrons into the polar atmosphere. Powerful events occurring on the Sun can drive enormous changes in the solar wind, increasing both its speed and density and enhancing its effect on Earth.
It has been recorded that once in France, the northern lights were believed to be
选项
A、a fire set by the enemy troops.
B、punishment to humans by God.
C、crimes which would enrage God.
D、an indication of the doomsday.
答案
B
解析
第3段倒数第2句中的the wrath of God常表示“上帝的怒火”,wrath通常暗示上帝因为愤怒而要惩罚世人,由此可见,本题应选B。本题最具干扰性的是D,doomsday是“世界末日”的意思,从原文的wrath可以知道上帝将要惩罚世人,但以什么方式惩罚却是不明确的,D说得过于绝对了。
转载请注明原文地址:https://kaotiyun.com/show/1yFK777K
0
专业英语四级
相关试题推荐
BlogOnestudyfoundthatmorethanonehundredeightymillionpeoplearoundtheworldhavestartedablog./Andmorethant
Nowherebutaroundthismountainarea______suchkindofcustominthepasttwentyyears.
LongitudeandLatitudeThemeridiansoflongitudeareimaginarygreatcirclesdrawnfrompoletopolearoundtheearth.By
LongitudeandLatitudeThemeridiansoflongitudeareimaginarygreatcirclesdrawnfrompoletopolearoundtheearth.By
Aroundoneinahundreddeathsworldwideisduetopassivesmoking,whichkillsanestimated600,000peopleayear,WorldHealth
Aroundoneinahundreddeathsworldwideisduetopassivesmoking,whichkillsanestimated600,000peopleayear,WorldHealth
Aroundoneinahundreddeathsworldwideisduetopassivesmoking,whichkillsanestimated600,000peopleayear,WorldHealth
Aroundoneinahundreddeathsworldwideisduetopassivesmoking,whichkillsanestimated600,000peopleayear,WorldHealth
随机试题
行政法律关系一般是指受法律规范调整的因行政权的形式而产生的一类法律关系。行政法律关系不仅具有法律关系的一般特征,还有其自身特点。下面关于行政法律关系自身特点的表述中错误的是()。
《土地管理法》对农地使用权的规定是我国国家关于农村政策的法律化定型化。关于农地使用权的法律特点,主要考虑()等方面。
有反应:Fe2O3(s)+3H2(g)2Fe(s)+3H2O(l),此反应的标准平衡常数表达式应是:
根据《建设工程安全生产条例》,违反本条例的规定,出租单位出租未经安全性能检测或者经检测不合格的机械设备和施工机具及配件的,责令停业整顿,并处______的罚款。
《如歌的行板》是俄国作曲家_________作品。
德育的任务有哪些?
下列体现了人类意识能动性的有()。
现在中国的就业市场似乎进入一个很矛盾的阶段,一方面,经济学家们大多认为,中国已经进入了刘易斯拐点,劳动力不再是无限供应的市场。甚至在某些行业出现了_______的现象。但另一方面,以我国人力资源和社会保障部的数据看,近年来我国农民工的总量一直呈现_____
请选择最适合的一项填入问号处,使之符合之前四个图形的变化规律。
利用SQL语句删除当前文件夹中一个名为temp的自由表文件为:【】temp。
最新回复
(
0
)