科学家发现对地球有潜在危险的小行星
文章来源:未知 文章作者:meng 发布时间:2010-09-28 01:08 字体: [ ]  进入论坛
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The Panoramic1(全景的) Survey Telescope & Rapid Response System (Pan-STARRS) PS1 telescope has discovered an asteroid2(小行星) that will come within 4 million miles of Earth in mid-October. The object is about 150 feet in diameter and was discovered in images acquired on September 16, when it was about 20 million miles away. It is the first "potentially hazardous3(有危险的) object" (PHO) to be discovered by the Pan-STARRS survey and has been given the designation "2010 ST3."

"Although this particular object won't hit Earth in the immediate4 future, its discovery shows that Pan-STARRS is now the most sensitive system dedicated5 to discovering potentially dangerous asteroids6," said Robert Jedicke, a University of Hawaii member of the PS1 Scientific Consortium, who is working on the asteroid data from the telescope. "This object was discovered when it was too far away to be detected by other asteroid surveys," Jedicke noted7.

The Harvard-Smithsonian Center for Astrophysics is a major partner in the Consortium.

Most of the largest PHOs have already been catalogued, but scientists suspect that there are many more under a mile across that have not yet been discovered. These could cause devastation8(毁坏,荒废) on a regional scale if they ever hit our planet. Such impacts are estimated to occur once every few thousand years.

Timothy Spahr, director of the Minor9 Planet Center (MPC), said, "I congratulate the Pan-STARRS project on this discovery. It is proof that the PS1 telescope, with its Gigapixel Camera and its sophisticated computerized system for detecting moving objects, is capable of finding potentially dangerous objects that no one else has found." The MPC, located in Cambridge, Mass., was established by the International Astronomical10 Union in 1947 to collect and disseminate11 positional measurements for asteroids and comets, to confirm their discoveries, and to give them preliminary designations.

Pan-STARRS expects to discover tens of thousands of new asteroids every year with sufficient precision to accurately12 calculate their orbits around the sun. Any sizable object that looks like it may come close to Earth within the next 50 years or so will be labeled "potentially hazardous" and carefully monitored. NASA experts believe that, given several years warning, it should be possible to organize a space mission to deflect14 any asteroid that is discovered to be on a collision course with Earth.

Pan-STARRS has broader goals as well. PS1 and its bigger brother, PS4, which will be operational later in this decade, are expected to discover a million or more asteroids in total, as well as more distant targets such as variable stars, supernovas(超新星) , and mysterious bursts from galaxies15 across more than half the universe. PS1 became fully13 operational in June 2010.



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1 panoramic LK3xM     
adj. 全景的
参考例句:
  • Most rooms enjoy panoramic views of the sea. 大多数房间都能看到海的全景。
  • In a panoramic survey of nature, speed is interesting because it has a ceiling. 概观自然全景,速率是有趣的,因为它有一个上限。
2 asteroid uo1yD     
n.小行星;海盘车(动物)
参考例句:
  • Astronomers have yet to witness an asteroid impact with another planet.天文学家还没有目击过小行星撞击其它行星。
  • It's very unlikely that an asteroid will crash into Earth but the danger exists.小行星撞地球的可能性很小,但这样的危险还是存在的。
3 hazardous Iddxz     
adj.(有)危险的,冒险的;碰运气的
参考例句:
  • These conditions are very hazardous for shipping.这些情况对航海非常不利。
  • Everybody said that it was a hazardous investment.大家都说那是一次危险的投资。
4 immediate aapxh     
adj.立即的;直接的,最接近的;紧靠的
参考例句:
  • His immediate neighbours felt it their duty to call.他的近邻认为他们有责任去拜访。
  • We declared ourselves for the immediate convocation of the meeting.我们主张立即召开这个会议。
5 dedicated duHzy2     
adj.一心一意的;献身的;热诚的
参考例句:
  • He dedicated his life to the cause of education.他献身于教育事业。
  • His whole energies are dedicated to improve the design.他的全部精力都放在改进这项设计上了。
6 asteroids d02ebba086eb60b6155b94e12649ff84     
n.小行星( asteroid的名词复数 );海盘车,海星
参考例句:
  • Asteroids,also known as "minor planets",are numerous in the outer space. 小行星,亦称为“小型行星”,在外太空中不计其数。
  • Most stars probably have their quota of planets, meteorids, comets, and asteroids. 多数恒星也许还拥有若干行星、流星、彗星和小行星。
7 noted 5n4zXc     
adj.著名的,知名的
参考例句:
  • The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
  • Jim is noted for arriving late for work.吉姆上班迟到出了名。
8 devastation ku9zlF     
n.毁坏;荒废;极度震惊或悲伤
参考例句:
  • The bomb caused widespread devastation. 炸弹造成大面积破坏。
  • There was devastation on every side. 到处都是破坏的创伤。 来自《简明英汉词典》
9 minor e7fzR     
adj.较小(少)的,较次要的;n.辅修学科;vi.辅修
参考例句:
  • The young actor was given a minor part in the new play.年轻的男演员在这出新戏里被分派担任一个小角色。
  • I gave him a minor share of my wealth.我把小部分财产给了他。
10 astronomical keTyO     
adj.天文学的,(数字)极大的
参考例句:
  • 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。
11 disseminate VtKxS     
v.散布;传播
参考例句:
  • We should disseminate science and promote the scientific spirit.普及科学知识,弘扬科学精神。
  • We sincerely welcome all countries to disseminate their languages in China.我们真诚地欢迎世界各国来华推广本国语言。
12 accurately oJHyf     
adv.准确地,精确地
参考例句:
  • It is hard to hit the ball accurately.准确地击中球很难。
  • Now scientists can forecast the weather accurately.现在科学家们能准确地预报天气。
13 fully Gfuzd     
adv.完全地,全部地,彻底地;充分地
参考例句:
  • The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气,然后全部呼出。
  • They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。
14 deflect RxvxG     
v.(使)偏斜,(使)偏离,(使)转向
参考例句:
  • Never let a little problem deflect you.决不要因一点小问题就半途而废。
  • They decided to deflect from the original plan.他们决定改变原计划。
15 galaxies fa8833b92b82bcb88ee3b3d7644caf77     
星系( galaxy的名词复数 ); 银河系; 一群(杰出或著名的人物)
参考例句:
  • Quasars are the highly energetic cores of distant galaxies. 类星体是遥远星系的极为活跃的核心体。
  • We still don't know how many galaxies there are in the universe. 我们还不知道宇宙中有多少个星系。
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