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
Sunspots act like planet-sized hurricanes that suck in as much material as they spew out, temporarily overriding the laws of mag
Sunspots act like planet-sized hurricanes that suck in as much material as they spew out, temporarily overriding the laws of mag
admin
2013-09-23
59
问题
Sunspots act like planet-sized hurricanes that suck in as much material as they spew out, temporarily overriding the laws of magnetic fields, scientists said on Tuesday.
A team of researchers from NASA and Stanford University said by peering into the Sun for the first time, they discovered how the magnetic fields, which make up the cool dark sunspots on the surface, clump together instead of dispersing. Scientists had previously observed gases pouring out of the sunspots, and thought this was the product of the various magnetic fields repelling each other, in the same way magnets repel each other when brought together. But the researchers said the out-flowing matter is just a surface feature that occurs while the sunspot sucks in new material to hold itself together.
"If you look a bit deeper, you find material rushing inward, like a planet-sized whirlpool or hurricane. This inflow pulls the magnetic fields(back)together, " said Junwei Zhao, one of the Stanford researchers. The pressure in this sunspot hurricane is about 10 times higher than a tropical hurricane on Earth, scientists said. "Without this flow, a sun-spot would not last a day. With it, it lasts for weeks. In the end, the sunspot does get torn apart—but we still don’t know how yet, " Stanford colleague Philip Scherrer, said at a news conference.
To get this deeper knowledge the team used sound wave technology, which they likened to the ultrasound doctors use to capture images of unborn babies. The research showed the magnetic field below a sunspot would cut off the spot’s supply of energy from the Sun’s hot core, turning it into a plug. Any matter above the plug would then cool and become denser, until gravity dragged it and any surrounding gases into the center of the spot at 3, 000 miles per hour. "As long as the magnetic field remains strong, the coding effect will maintain an inflow that makes the structure stable... thereby setting up a self-perpetuating cycle, " the team said in its report.
British scientist Douglas Gough from Cambridge University, described the group’s findings as the solution to a 400-year-old riddle. Understanding the sunspot component would help scientists gain a global knowledge of the Sun, he said. "Take a TV set. It is not simply the sum of its components. And trying to understand the whole requires a greater global knowledge, but you can’t build a TV set unless you know how the components work. It’s the same with the Sun and its components, " Gough said.
The findings are the latest in a long line of sunspot research, which stems back to the early 17th century, when Italian astronomer Galileo Galilei used sunspots to calculate the speed of the Sun’s rotation. His hand-drawn renditions of sunspot locations contrasted sharply with the computer-generated multicolored models of sunspots on display at NASA’s Washington headquarters. "Imagine yourself flying over a lake, you can see the surface but you don’t know how deep it is, how the temperature varies with depth. It was the same with sunspots until now, " NASA’s George Withbroe said.
The sunspot hurricane is about______times higher than a tropical hurricane on Earth.
选项
A、10
B、10 billion
C、10 thousand
D、100
答案
A
解析
细节题。只需在略读时留意,便可从第三段中“The pressure in this sunspothurricane is about 10 times higher than a tropical hurricane on Earth,scientists said.”一句中找到答案[A]。
转载请注明原文地址:https://kaotiyun.com/show/OWLK777K
0
专业英语四级
相关试题推荐
Mostparentshopethattheirchildrenwill________theirexpectations.
Thetouristtradeisbooming.Withallthiscomingandgoing,you’dexpectgreater’understandingtodevelopbetweenthenatio
What’syourearliestchildhoodmemory?Canyourememberlearningtowalk?Ortalk?Thefirsttimeyou【C1】______thunderor
What’syourearliestchildhoodmemory?Canyourememberlearningtowalk?Ortalk?Thefirsttimeyou【C1】______thunderor
What’syourearliestchildhoodmemory?Canyourememberlearningtowalk?Ortalk?Thefirsttimeyou【C1】______thunderor
Inresponsetotoday’sWorldTradeOrganization(WTO)AppellateBodydecisiondeclaringtheBushAdministration’sSection201st
AstronomersattheUniversityofCaliforniadiscoveredoneofthemostdistant______
Aestheticthoughtofadistinctivelymodernbentemergedduringthe18thcentury.Thewesternphilosophersandcriticsofthist
Oneoftherequirementsforafireisthatthematerial______toitsburningtemperature.
Howlongdoesittaketocovertheworkbookmaterial?
随机试题
驾驶技巧准考证明的有效期是多久?
未成年工是指年满()周岁的劳动者。
甲企业向乙银行贷款1千万元,还款期限为2010年3月16日。2008年3月16日,甲、乙签订书面抵押合同,约定甲以现有以及将有的动产设立抵押,2008年4月16日双方到甲企业住所地的工商局办理了抵押登记。2009年12月16日,经评估师估价,甲企业将闲置的
在EPC模式下,()承担了工程的大部分风险。
我国实行9年制义务教育制度,下列不属于义务教育的基本特征的是()。
下列词语中没有错别字的一组是()
长春市轨道交通2号线已投入运营,在工程建设中用量最大的硅酸盐材料是
一个进程被唤醒,意味着(16)。
A、Right.B、Wrong.C、Doesn’tSay.A
Istheremeaninginthelengthofafinger?Longfingersarea【C1】______ofrefinement.Ashortstubbyhandarguesalackof【C2】_
最新回复
(
0
)