NASA's probe confirms Einstein space-time theories

     WASHINGTON, May 4 (Xinhua) -- The U.S. National Aeronautics¹ and Space Administration (NASA) announced Wednesday that its Gravity Probe B (GP-B) mission has confirmed two key predictions（预测预言） derived² from Albert Einstein's general theory of relativity, which the spacecraft was designed to test.

    The experiment, launched in 2004, used four ultra-precise gyroscopes to measure the hypothesized geodetic effect, the warping³ of space and time around a gravitational body, and frame- dragging, the amount a spinning object pulls space and time with it as it rotates.

    GP-B determined⁴ both effects with unprecedented⁵ precision by pointing at a single star, IM Pegasi, while in a polar orbit around Earth. If gravity did not affect space and time, GP-B's gyroscopes would point in the same direction forever while in orbit. But in confirmation⁶ of Einstein's theories, the gyroscopes experienced measurable, minute changes in the direction of their spin, while Earth's gravity pulled at them.

    The findings are available online in the journal Physical Review Letters.

    "Imagine the Earth as if it were immersed in honey. As the planet rotates, the honey around it would swirl⁷, and it's the same with space and time," said Francis Everitt, GP-B principal investigator⁸ at Stanford University. "GP-B confirmed two of the most profound predictions of Einstein's universe, having far- reaching implications across astrophysics research."GP-B is one of the longest running projects in NASA history, with agency involvement starting in the fall of 1963 with initial funding to develop a relativity gyroscope experiment. Subsequent decades of development led to groundbreaking technologies to control environmental disturbances⁹ on spacecraft, such as aerodynamic drag, magnetic fields and thermal¹⁰ variations. The mission's star tracker and gyroscopes were the most precise ever designed and produced.

    GP-B completed its data collection operations and was decommissioned in December 2010.

    "The mission results will have a long-term impact on the work of theoretical physicists," said Bill Danchi, senior astrophysicist and program scientist at NASA Headquarters in Washington. "Every future challenge to Einstein's theories of general relativity will have to seek more precise measurements than the remarkable¹¹ work GP-B accomplished¹²."(本文由在线英语听力室整理编辑)

1 aeronautics   

n.航空术，航空学

参考例句：

• National Aeronautics and Space undertakings have made great progress.国家的航空航天事业有了很大的发展。
• He devoted every spare moment to aeronautics.他把他所有多余的时间用在航空学上。

2 derived   

vi.起源；由来；衍生；导出v.得到( derive的过去式和过去分词 )；（从…中）得到获得；源于；（从…中）提取

参考例句：

• Many English words are derived from Latin and Greek. 英语很多词源出于拉丁文和希腊文。 来自《简明英汉词典》
• He derived his enthusiasm for literature from his father. 他对文学的爱好是受他父亲的影响。 来自《简明英汉词典》

3 warping   

n.翘面，扭曲，变形v.弄弯，变歪( warp的现在分词 )；使（行为等）不合情理，使乖戾，

参考例句：

• Tilting, warping, and changes in elevation can seriously affect canals and shoreline facilities of various kinks. 倾斜、翘曲和高程变化可以严重地影响水渠和各种岸边设备。 来自辞典例句
• A warping, bending, or cracking, as that by excessive force. 翘曲，弯曲，裂开：翘曲、弯曲或裂开，如过强的外力引起。 来自互联网

4 determined   

adj.坚定的；有决心的

参考例句：

• I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
• He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。

5 unprecedented   

adj.无前例的，新奇的

参考例句：

• The air crash caused an unprecedented number of deaths.这次空难的死亡人数是空前的。
• A flood of this sort is really unprecedented.这样大的洪水真是十年九不遇。

6 confirmation   

n.证实，确认，批准

参考例句：

• We are waiting for confirmation of the news.我们正在等待证实那个消息。
• We need confirmation in writing before we can send your order out.给你们发送订购的货物之前，我们需要书面确认。

7 swirl   

v.(使)打漩，(使)涡卷；n.漩涡，螺旋形

参考例句：

• The car raced roughly along in a swirl of pink dust.汽车在一股粉红色尘土的漩涡中颠簸着快速前进。
• You could lie up there,watching the flakes swirl past.你可以躺在那儿，看着雪花飘飘。

8 investigator   

n.研究者，调查者，审查者

参考例句：

• He was a special investigator for the FBI.他是联邦调查局的特别调查员。
• The investigator was able to deduce the crime and find the criminal.调查者能够推出犯罪过程并锁定罪犯。

9 disturbances   

n.骚乱( disturbance的名词复数 )；打扰；困扰；障碍

参考例句：

• The government has set up a commission of inquiry into the disturbances at the prison. 政府成立了一个委员会来调查监狱骚乱事件。
• Extra police were called in to quell the disturbances. 已调集了增援警力来平定骚乱。

10 thermal   

adj.热的，由热造成的；保暖的

参考例句：

• They will build another thermal power station.他们要另外建一座热能发电站。
• Volcanic activity has created thermal springs and boiling mud pools.火山活动产生了温泉和沸腾的泥浆池。

11 remarkable   

adj.显著的，异常的，非凡的，值得注意的

参考例句：

• She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
• These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。

12 accomplished   

adj.有才艺的；有造诣的；达到了的

参考例句：

• Thanks to your help,we accomplished the task ahead of schedule.亏得你们帮忙,我们才提前完成了任务。
• Removal of excess heat is accomplished by means of a radiator.通过散热器完成多余热量的排出。