文章来源:未知 文章作者:meng 发布时间:2010-01-05 05:31 字体: [ ]  进入论坛

Nasa's Kepler Space Telescope has detected its first five exoplanets, or planets beyond our Solar System.



The observatory1, which was launched last year to find other Earths, made the discoveries in its first few weeks of science operations.

Although the new worlds are all bigger than our Neptune海王星, the US space agency says the haul shows the telescope is working well and is very sensitive.

The exoplanets外部行星 have been given the names Kepler 4b, 5b, 6b, 7b and 8b.

They were announced at an American Astronomical3 Society meeting in Washington DC.

The planets range in size from an object that has a radius4 four times that of Earth, to worlds much bigger than even our Jupiter木星.

And they all circle very close to their parent stars, following orbits that range from about 3.2 to 4.9 days.

This proximity亲近,接近 and the fact that the host stars are themselves much hotter than our Sun means Kepler's new exoplanets experience an intense roasting灼热的.

Intriguing6 density7

Estimated temperatures go from about 1,200C to 1,650C (2,200F to 3,000F).

"The planets we found are all hotter than molten lava8火山岩浆; they all simply glow with their temperatures," said Bill Borucki, Kepler's lead scientist from Nasa's Ames Research Center in Moffett Field, California.

"In fact the upper two are hotter than molten iron and looking at them might be like looking at a blast furnace高炉. They are very bright in their own right and certainly no place to look for life."

Kepler 7b will intrigue激起……兴趣 many scientists. It is one of the lowest-density exoplanets (about 0.17 grams per cubic centimetre) yet discovered.

"The average density of this planet with its core is about the same as Styrofoam," explained Dr Borucki. "So it's an amazingly light planet, something I'm sure theoreticians will be delighted to look at in terms of trying to understand [its] structure."

Kepler blasted into space atop a Delta9 II rocket from Cape10 Canaveral Air Force Station on 6 March, 2009.

It is equipped with the largest camera ever launched into space. The telescope's mission is to continuously and simultaneously11 observe more than 100,000 stars.

It senses the presence of planets by looking for a tiny "shadowing" effect when one of them passes in front of its parent star.

'Water worlds'

Kepler's detectors12, built by UK firm e2v, have extraordinary sensitivity.

Nasa says that if the observatory were to look down at a small town on Earth at night from space, it would be able to detect the dimming of a porch门廊,走廊 light as somebody passed in front of it.

The space agency hopes this sensitivity will lead it to planets that are not only Earth-size but which orbit their stars at distances more favourable13 to life, where liquid water might potentially reside属于,居住 on their surfaces.

The mission's scientists told the AAS meeting that Kepler had measured hundreds of possible planet signatures but that these needed further investigation14 to establish their true nature.

To confirm the existence of the most ideal Earth-like planets would take a few years, they warned.

In the meantime, all detections will help scientists improve their statistics on the distributions of planet size and orbital period.

The follow-up observations needed to confirm the new exoplanets' existence used a suite15 of ground-based facilities including the Keck I telescope in Hawaii.


1 observatory hRgzP     
  • Guy's house was close to the observatory.盖伊的房子离天文台很近。
  • Officials from Greenwich Observatory have the clock checked twice a day.格林威治天文台的职员们每天对大钟检查两次。
2 Neptune LNezw     
  • Neptune is the furthest planet from the sun.海王星是离太阳最远的行星。
  • Neptune turned out to be a dynamic,stormy world.海王星原来是个有生气、多风暴的世界。
3 astronomical keTyO     
  • He was an expert on ancient Chinese astronomical literature.他是研究中国古代天文学文献的专家。
  • Houses in the village are selling for astronomical prices.乡村的房价正在飙升。
4 radius LTKxp     
  • He has visited every shop within a radius of two miles.周围两英里以内的店铺他都去过。
  • We are measuring the radius of the circle.我们正在测量圆的半径。
5 proximity 5RsxM     
  • Marriages in proximity of blood are forbidden by the law.法律规定禁止近亲结婚。
  • Their house is in close proximity to ours.他们的房子很接近我们的。
6 intriguing vqyzM1     
  • These discoveries raise intriguing questions. 这些发现带来了非常有趣的问题。
  • It all sounds very intriguing. 这些听起来都很有趣。 来自《简明英汉词典》
7 density rOdzZ     
  • The population density of that country is 685 per square mile.那个国家的人口密度为每平方英里685人。
  • The region has a very high population density.该地区的人口密度很高。
8 lava v9Zz5     
  • The lava flowed down the sides of the volcano.熔岩沿火山坡面涌流而下。
  • His anger spilled out like lava.他的愤怒像火山爆发似的迸发出来。
9 delta gxvxZ     
  • He has been to the delta of the Nile.他曾去过尼罗河三角洲。
  • The Nile divides at its mouth and forms a delta.尼罗河在河口分岔,形成了一个三角洲。
10 cape ITEy6     
  • I long for a trip to the Cape of Good Hope.我渴望到好望角去旅行。
  • She was wearing a cape over her dress.她在外套上披着一件披肩。
11 simultaneously 4iBz1o     
  • The radar beam can track a number of targets almost simultaneously.雷达波几乎可以同时追着多个目标。
  • The Windows allow a computer user to execute multiple programs simultaneously.Windows允许计算机用户同时运行多个程序。
12 detectors bff80b364ed19e1821aa038fae38df83     
探测器( detector的名词复数 )
  • The report advocated that all buildings be fitted with smoke detectors. 报告主张所有的建筑物都应安装烟火探测器。
  • This is heady wine for experimenters using these neutrino detectors. 对于使用中微子探测器的实验工作者,这是令人兴奋的美酒。 来自英汉非文学 - 科技
13 favourable favourable     
  • The company will lend you money on very favourable terms.这家公司将以非常优惠的条件借钱给你。
  • We found that most people are favourable to the idea.我们发现大多数人同意这个意见。
14 investigation MRKzq     
  • In an investigation,a new fact became known, which told against him.在调查中新发现了一件对他不利的事实。
  • He drew the conclusion by building on his own investigation.他根据自己的调查研究作出结论。
15 suite MsMwB     
  • She has a suite of rooms in the hotel.她在那家旅馆有一套房间。
  • That is a nice suite of furniture.那套家具很不错。
TAG标签: planet solar exoplanets