首页
登录
职称英语
Ever since its discovery, Pluto has never really fitted in. After the pale a
Ever since its discovery, Pluto has never really fitted in. After the pale a
游客
2025-04-18
34
管理
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. " [br] The word "commotion" in the expression "New York’s Hayden Planetarium caused a commotion two years ago"(Para. 8)can be replaced by______.
选项
A、exchange of opinions
B、thorough investigation
C、wild imagination
D、agitated confusion
答案
D
解析
本题考查词汇。根据倒数第二段第一句和第二句内容“New York’s HaydenPlanetarium caused a commotion two years ago by supposedly demoting Pluto,lumping itwith 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 astro—physicist there.”可知,两年前,位于纽约的海顿天文馆引起了一次骚动,因为天文馆想把冥王星降级,把其归为在太阳系中移动的库伯带小行星物体。那里的天文学家尼尔·D·泰森说,事实上天文馆这一举动意义重大。由此可知,D项符合题意。
转载请注明原文地址:https://tihaiku.com/zcyy/4043624.html
相关试题推荐
WenowfindthatagreatmanythingswethoughtwereNaturalLawsarereally
WenowfindthatagreatmanythingswethoughtwereNaturalLawsarereally
WenowfindthatagreatmanythingswethoughtwereNaturalLawsarereally
Thinkaboutwhatwouldmakeyoureally,reallyhappy.Moremoney?Wrong.Smi
Thinkaboutwhatwouldmakeyoureally,reallyhappy.Moremoney?Wrong.Smi
Thinkaboutwhatwouldmakeyoureally,reallyhappy.Moremoney?Wrong.Smi
Thinkaboutwhatwouldmakeyoureally,reallyhappy.Moremoney?Wrong.Smi
Thinkaboutwhatwouldmakeyoureally,reallyhappy.Moremoney?Wrong.Smi
Thinkaboutwhatwouldmakeyoureally,reallyhappy.Moremoney?Wrong.Smi
Thinkaboutwhatwouldmakeyoureally,reallyhappy.Moremoney?Wrong.Smi
随机试题
有档案保管条件不符合规定要求、未按规定向档案馆移交档案等行为的,县级以上档案行政
现金预算的内容不包括()。A.经营现金收入 B.经营现金支出 C.预计实
男性,67岁,拟在体外循环下行冠状动脉旁路移植术。术前药物治疗不包括 A.钙通
介绍经纪商(简称IB)这一称呼来源于(),在国际上既可以是机构,也可以是个人,
下列不属于更年期综合征的是A.生殖器官逐渐萎缩 B.阴道分泌物增多 C.尿急
二恶英是一种持久性有机污染物,目前对二恶英的治理存在各种方面的验证题。首先,对二
A.3yy´=1 B. C.y´=3y+1 D.
简述现代企业人力资源管理各个历史发展阶段的特点。
银行业监管的发展历程在表象上反映为管制、放松、重新管制。()
高渗性缺水与低渗性缺水临床表现的主要鉴别点是A.手足麻木 B.口渴明显 C.
最新回复
(
0
)