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
The discovery of planets around distant stars has become like space-shuttle launches — newsworthy but just barely. With some 50
The discovery of planets around distant stars has become like space-shuttle launches — newsworthy but just barely. With some 50
admin
2010-04-24
64
问题
The discovery of planets around distant stars has become like space-shuttle launches — newsworthy but just barely. With some 50 extra solar planets under their belt, astronomers have to announce something really strange to get anyone’s attention.
Last week they did just that. Standing in front of colleagues and reporters at the American Astronomical Society’s semiannual meeting in San Diego, the world’s premier planet-hunting team — astronomer Geoffrey Marcy of the University of California, Berkeley, and his colleagues — presented not one but two remarkable finds. The first is a pair of planets, each about the mass of Jupiter, which whirl around their home star 15 light-years from Earth in perfect lockstep. One takes 30 days to complete an orbit, the other exactly twice as long. Nobody has ever seen such a configuration. But the second discovery is far stranger — a solar system 123 light-years away, in the constellation Serpens, that harbors one "ordinary" planet and another so huge — 17 times as massive as Jupiter — that nobody can quite figure out what it can be. It is, says Marcy, "a bit frightening".
What’s frightening is that these discoveries make it clear how little astronomers know about planets, and they add to the dawning realization that our solar system — and by implication Planet Earth — may be a cosmic oddball. For years theorists figured that other stars would have planets more or less like the ones going mound the sun. But staffing with the 1995 discovery of the first extra solar planet — a gassy monster like Jupiter but orbiting seven times as close to its star as Metcury orbits around our sun — each new find has seemed stranger than the last. Searchers have found more "hot Jupiters’ like that first discovery. These include huge planets that career around their stars not in circular orbits but in elongated ones; their gravity would send any Earthlike neighbors flying off into space. Says Princeton astronomer Scott Tremaine: "Not a single prediction for what we’d find in other systems has turned out to be correct."
Last week’s giant was the most unexpected discovery yet. Conventional theory, suggests that it must have formed like a star, from a collapsing cloud of interstellar gas. Its smaller companion, only seven times Jupiter’s mass, is almost certainly a planet, formed by the buildup of gas and dust left over from a star’s formation. Yet the fact that these two orbs are so close together suggests to some theorists that they must have formed together — so maybe the bigger one is a planet after all.
Or maybe astronomers will have to rethink their definition of "planet". Just because we put heavenly objects into categories doesn’t mean the distinctions are necessarily valid. And as Tremaine puts it, "When your classification schemes start breaking down, you know you’re learning something exciting. This is wonderful stuff."
The author believes that _____.
选项
A、there is little for astronomers to discover now
B、the public have no interest in astronomical discoveries
C、astronomers have been making a lot of discoveries of planets
D、the discovery of planets is as important as the launch of space shuttles
答案
C
解析
细节题。第一段第二句说With some 50 extra solar planets under their belt,意即宇航员已经发现了五十多个行星,是非常多的,所以C正确。
转载请注明原文地址:https://kaotiyun.com/show/vt2K777K
0
专业英语四级
相关试题推荐
TheMastersofBusinessAdministration(MBA),thebest-knownbusinessschoollabel,isanintroductiontogeneralmanagement.Th
ThismonthBritain’sbusinessschoolswillletlooseanotherbatchofgraduates,peoplewell-versedinthetheoriesofmarketing
ThismonthBritain’sbusinessschoolswillletlooseanotherbatchofgraduates,peoplewell-versedinthetheoriesofmarketing
WhatwasthemostimportantjobfortheastronautsofDiscovery?
WhatwasthemostimportantjobfortheastronautsofDiscovery?
WhatwasthemostimportantjobfortheastronautsofDiscovery?
Somepessimisticexpertsfeelthattheautomobileisboundtofallintodisuse.Theyseeadayinthenot-too-distantfuturewhe
Sincewearesocialbeings,thequalityofourlivesdependsinlargemeasureonourinterpersonalrelationships.Onestrengtho
Mostpeoplewhotravellongdistancescomplainofjetlag.Jetlagmakesbusinesstravelerslessproductiveandmoreprone【C1】____
随机试题
咨询者,女,32岁,大学教师。3个月前因职称晋升失败与领导争吵,而后逐渐出现失眠,早醒,情绪低落,兴趣减退,对未来悲观失望,认为领导有意不让她晋升,能主动求医,接触良好。针对该来询者,心理评估宜采用()
A."一个人能力有大小,但只要有这点精神,就是一个高尚的人,一个纯粹的人,一个有道德的人,一个脱离了低级趣味的人,一个有益于人民的人"B."上以疗君亲之疾,下以救贫贱之厄"C."若有疾厄来求救者,不得问其贵贱贫富、长幼妍媸、怨亲善友、华夷愚智,普同一等
承担传染病防治职责的机构是
甲为某普通合伙企业的合伙人,在企业经营期间,甲因车祸丧生,甲的合法继承人乙年方15岁,该合伙企业的合伙协议中约定,合伙人死亡后,经合伙人一致同意的,由其继承人继承合伙人资格。依我国《合伙企业法》规定,以下各项中不正确的有:()
【2017年真题】为确保政府财政承受能力,每一年全部PPP项目需要从预算中安排的支出占一股公共预算支出的比例,应当不超过()。
二级轻型井点降水,降水深度为()。
壁纸原纸
我国长期以来采用的政府间转移支付模式是()。
设f(x),g(x)在[a,b]上连续,在(a,b)内可导,且f(a)=f(6)=0,证明:存在ξ∈(a,b),使得f’(ξ)+f(ξ)g’(ξ)=0.
按照“香蕉”曲线图法的表述,实际进度处于最早计划时间之上表示______。
最新回复
(
0
)