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
Ever since its discovery, Pluto has never really fitted in. After the pale and glowing giant Neptune, it is little more than a c
Ever since its discovery, Pluto has never really fitted in. After the pale and glowing giant Neptune, it is little more than a c
admin
2013-03-27
67
问题
Ever since its discovery, Pluto has never really fitted in. After the pale and glowing giant Neptune, it is little more than a cosmic dust mite, swept through the farthest reaches of the solar system on a planet wildly tilted relative to the rest of the planets. It is smaller than Neptune’s largest moon, and the arc of its orbit is so oval that it occasionally crosses its massive blue neighbor’s path.
For years, it has been seen as our solar system’s oddest planet Yesterday, however, scientists released perhaps the most convincing evidence yet that Pluto, in fact, is not a planet at all. For the first time, astronomers have peered into a belt of rocks beyond Pluto unknown until 10 years ago—and found a world that rivals Pluto in size. The scientists posit that larger rocks must be out there, perhaps even larger than Pluto, meaning Pluto is more likely the king of this distant realm of space detritus than the tiniest of the nine planets.
When discovered in 1930, "Pluto at that point was the only thing(that far)out there, so there was nothing else to call it but a planet," says Mike Brown, an astronomer at the California Institute of Technology in Pasadena. "Now it just doesn’t fit. " In one sense, the question of Pluto’s planetary status is arcane, the province of pocket-protected scientists and sun-deprived pen pushers determined to decide some official designation for a ball of dust and ice 3 billion miles away.
Yet it is also unquestionably something more. From science fair dioramas to government funding, planets hold a special place in the public imagination, and how Pluto is eventually seen—by kids and Congress alike—could shape what future generations learn about this mysterious outpost on the edge of the solar system. The debate has split the astronomical community for decades. Even before the distant band of rocks known as the Kuiper Belt was found, Pluto’s unusual behavior made it suspicious.
Elsewhere, the solar system fit into near families; the rocky inner planets, the asteroid belt, the huge and gaseous outer planets. Pluto, though, was peculiar. With the discovery of the Kuiper Belt—countless bits of rock and ice left unused when the wheel of the solar system first formed—Pluto suddenly seemed to have cousins. Yet until yesterday, it held to its planetary distinction because it was far larger than anything located there.
The rub now is Quaoar(pronounced KWAH-oar), 1 billion miles beyond Pluto and roughly half as large. Named after the creation force of the tribe that originally inhabited the Los Angeles basin, Quaoar forecasts problems for the erstwhile ninth planet, says discoverer Dr. Brown: "The case is going to get a lot harder to defend the day somebody finds something larger than Pluto,"
To some, the problem is not with Pluto, but the definition of "planet. " In short, there is none. To the Greeks, who coined the term, it meant "wanderer," describing the way that the planets moved across the night sky differently from the stars behind them. Today, with our more nuanced understanding of the universe, the word no longer has much scientific meaning.
New York’s Hayden Planetarium caused a commotion two years ago by supposedly demoting Pluto, lumping it with the Kuiper Belt objects in its huge mobile of the solar system. In reality, however, the planetarium was making a much broader statement, says Nell Degrasse Tyson, an astrophysicist there. The textbooks of the future should focus more on families of like objects than "planets. " The discovery of Quaoar strengthens this idea: "Everyone needs to rethink the structure of our solar system," he says. "We’ve just stopped counting planets. "
Still, many are loath to part with the planet Pluto. They note that Pluto, in fact, is distinct from many Kuiper Belt objects. It has a thin atmosphere, for one. It reflects a great deal of light, while most Kuiper Belt objects are very dark. And unlike all but a handful of known Kuiper Belt objects, it has a moon. "Maybe Pluto, then, should be representative of a new class of planets," says Mark Sykes, an astronomer at the University of Arizona in Tucson. "It’s the first example, and we are just beginning to find this category. "
Which of the following is true according to the passage?
选项
A、Rocks larger than Pluto have been found in the Kuiper Belt.
B、The Kuiper Belt did not exist when Pluto was first discovered.
C、The astronomers are divided with regard to the status of Pluto.
D、There is almost no difference between Pluto and other Kuiper Belt objects.
答案
C
解析
本题为细节题。根据第四段内容“The debate has split the astronomical community for decades.”可知,几十年来争论一直分化着天文界。由此可知,C项符合题意。
转载请注明原文地址:https://kaotiyun.com/show/ZNmO777K
0
考博英语
相关试题推荐
Thetextureofthesoildependsontherelativeamountsofdifferent-sizedparticlesthatcombinetomakeupthesoil.Thesepar
Statesareconsideringmajorchangesinprepaidcollegetuitionprograms——raisingprices,restrictingparticipationorcanceling
Socialpsychologistsarcusedtohearingthattheirexperimentsareawasteoftimebecausetheyjustprovetheobvious,andtel
Noothercountryspendswhatwedopercapitaformedicalcare.Thecareavailableisamongthebesttechnically,evenifusedt
Hasanyoneseenmyextradigitalcamerabattery?I’mthatdesperate.Iamnotadaptingwelltothisworldwherevaluableele
InmostAmericancities,thetentforaone-bedroomapartmentwas$250ormorepermonthinrecentyears.Insomesmallercities
AlthoughIknowthatmanyofyouthinktheopposite,mosthumanbeingshaveahighlevelofintelligence,agoodmemoryandcan
Anumberofarticleshavebeenpublishedbypsychologistsinfavoroftheirprocessionbeingpermittedtoprescribepsychotropic
NationalParkshavemoreandmorevisitorseachyear.Inthelasttenyearsthenumberofcampersusingthecampsiteshasmore
Itwasdifficulttobuildapowerstationinthedeepvalley,butit______aswehadhoped.
随机试题
下面4个关于C语言的结论中错误的是()。
对直径大于()的损伤,先贴上补伤片,最后在修补处包覆一条热收缩带。
我国产品若销往美国、加拿大,则应使用的条形码是()
智力是下列哪种能力的综合?()
Tony’smouthwatered______thebigpudding.
与统计抽样法相比,判断抽样法的优点是()。
某村作为一个侗族为主的村寨,传统上对自然资源有较好的管理体系;但随着市场经济的发展,政府的干预不当,在社区自然资源的管理上面临集体力量的丧失,保护机制不完善,社区能力不足。某社会服务机构了解到这一情况,在针对该村村民的一次小组工作中,通过外部的支持,依靠当
讯问不满18周岁的未成年犯罪嫌疑人时,除有碍侦查或者无法通知的情形外,可以通知其法定代理人或者教师到场,这是为了保障未成年人的合法权益。()
基于题干,回答问题以下是在一场关于“安乐死是否应合法化”的辩论中正反方辩手的发言:正方:反方辩友反对“安乐死合法化”的根据主要是在什么条件下方可实施安乐死的标准不易掌握,这可能会给医疗事故甚至谋杀造成机会,使一些本来可以挽救的生命失去最后的机会。诚然,这样
Astheworldhasmovedintoascientificage,theoriginofherbalmedicineinmanycountriesremainsshroudedinmysteryandof
最新回复
(
0
)