2006年VOA标准英语-NASA Says Oldest Mars Satellite May be Dead

By David McAlary
Washington
21 November 2006

The U.S. space agency NASA says its oldest satellite orbiting Mars has probably ended its career. NASA engineers lost contact with it about three weeks ago and are losing hope of ever hearing from it again. But NASA is celebrating its accomplishments¹ rather than mourning its apparent death.

Artist's concept of Mars Global Surveyor

The Mars Global Surveyor arrived at the red planet nine years ago. It was the first of several orbiters that are surveying the cold, barren landscape, looking especially for signs of water and relaying signals from the two robotic rovers crawling over the terrain².

For nine years it pumped out data until November 2, when it emerged from a communications blackout behind Mars and never beamed another signal.

NASA's lead Mars exploration scientist, Michael Meyer, speaks of it reverentially.

"We may have lost a dear old friend and teacher, Mars Global Surveyor," he said.  "This mission launched on November 7, 1996 has not only exceeded her design lifetime by five-fold, but it has changed our concept of the red planet."

NASA says the spacecraft may no longer be able to generate enough power to communicate. There are signs that a solar energy panel appears unable to pivot³ easily and track the sun. But engineers are exploring other possible reasons for the radio silence.

They are also trying to detect it through other U.S. craft at Mars. The newest Mars satellite, the Mars Reconnaissance Orbiter, pointed⁴ its cameras toward the Global Surveyor Monday, but preliminary analysis of the images shows no sightings. NASA is also employing one of its two ground rovers, the Opportunity, to try to listen for a weak signal from the silent satellite.

But the agency's Mars Program Manager, Fuk Li, says the prospects⁵ for recovery are not good.

"We are still holding out some hope, but we are fully⁶ prepared in our hearts that we may never be able to talk to the spacecraft again," noted⁷ Mr. Li.  "But we are also fully prepared to celebrate the fact that it has been a job well done."

Mars Global Surveyor has operated longer than any spacecraft ever sent to the red planet.  NASA cites many of its important discoveries, several of which point to clear signs that water flowed in the red planet's recent history. The agency plans to send future spacecraft to areas once covered by water in the hope of finding signs of past life.

The Global Surveyor found gullies that appear to have been cut by water in relatively⁸ modern times. It sensed a mineral called hematite that often forms under wet conditions. It found a fan-shaped area of interweaving, curved ridges⁹ interpreted as evidence of an ancient river delta¹⁰. It showed that Mars' polar ice caps are made of frozen water, not frozen carbon dioxide as previously¹¹ thought.

The satellite also found local magnetic fields, indicating that Mars once had a global magnetic field like Earth's, shielding it from cosmic rays. Because it worked so long, it was able to track environmental changes through many annual cycles.

"Mars Global Surveyor has generated a tremendous legacy¹², not only in the discoveries at hand, but also in the future scientific surprises to be discovered from the ongoing¹³ analyses," added Michael Meyer.

1 accomplishments   

n.造诣；完成( accomplishment的名词复数 )；技能；成绩；成就

参考例句：

• It was one of the President's greatest accomplishments. 那是总统最伟大的成就之一。
• Among her accomplishments were sewing,cooking,playing the piano and dancing. 她的才能包括缝纫、烹调、弹钢琴和跳舞。 来自《现代英汉综合大词典》

2 terrain   

n.地面，地形，地图

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• He knows the terrain of this locality like the back of his hand.他对这一带的地形了如指掌。

3 pivot   

v.在枢轴上转动；装枢轴，枢轴；adj.枢轴的

参考例句：

• She is the central pivot of creation and represents the feminine aspect in all things.她是创造的中心枢轴，表现出万物的女性面貌。
• If a spring is present,the hand wheel will pivot on the spring.如果有弹簧，手轮的枢轴会装在弹簧上。

4 pointed   

adj.尖的，直截了当的

参考例句：

• He gave me a very sharp pointed pencil.他给我一支削得非常尖的铅笔。
• She wished to show Mrs.John Dashwood by this pointed invitation to her brother.她想通过对达茨伍德夫人提出直截了当的邀请向她的哥哥表示出来。

5 prospects   

n.希望，前途(恒为复数)

参考例句：

• There is a mood of pessimism in the company about future job prospects. 公司中有一种对工作前景悲观的情绪。
• They are less sanguine about the company's long-term prospects. 他们对公司的远景不那么乐观。

6 fully   

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。

7 noted   

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 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

9 ridges   

n.脊( ridge的名词复数 )；山脊；脊状突起；大气层的)高压脊

参考例句：

• The path winds along mountain ridges. 峰回路转。
• Perhaps that was the deepest truth in Ridges's nature. 在里奇斯的思想上，这大概可以算是天经地义第一条了。

10 delta   

n.（流的）角洲

参考例句：

• 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。

11 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

12 legacy   

n.遗产，遗赠；先人(或过去)留下的东西

参考例句：

• They are the most precious cultural legacy our forefathers left.它们是我们祖先留下来的最宝贵的文化遗产。
• He thinks the legacy is a gift from the Gods.他认为这笔遗产是天赐之物。

13 ongoing   

adj.进行中的，前进的

参考例句：

• The problem is ongoing.这个问题尚未解决。
• The issues raised in the report relate directly to Age Concern's ongoing work in this area.报告中提出的问题与“关心老人”组织在这方面正在做的工作有直接的关系。