2007年VOA标准英语-Three Years Later Mars Rovers Keep Going
时间：2019-02-03 作者：英语课 分类：2007年VOA标准英语（一月）
By David McAlary
Washington
04 January 2007
Two U.S. robotic rovers are entering their fourth year exploring opposite sides of Mars, an unexpected length of time for a mission planned for only three months. Yet, now after three years, the mechanical geologists 1 keep plodding 2 along, studying Martian rocks and soil. Although they show certain signs of aging, VOA's David McAlary reports that new computer software has given them expanded capabilities 3, proving you can teach an old robot new tricks.
Mars Rover
It was January 3, 2004 when the exploration rover Spirit plunged 4 through Mars' atmosphere in a protective balloon-like cocoon 5 and bounced to a stop inside a crater 6.
As an expectant team of scientists and engineers waited tensely at the Jet Propulsion Laboratory in California, mission controllers followed its trajectory 7.
Mission controller: "A signal indicates we are bouncing on the surface of Mars. This is a very good sign."
Three weeks later, the rover Opportunity did the same on the other side of Mars.
The U.S. space agency NASA had thought that the planet's extremely frigid 8 temperatures and dust storms would keep their lives short. But rover project scientist Albert Haldemann notes that they have far exceeded their planned lifetime.
"We expected some extended mission lifetime," he said. "We designed the warranty 9 for these rovers for three months on Mars and we tested for nine months. So one might expect that we would have gotten nine months for free, and here we are at three years."
The twin rovers' major findings came within the first 90 days. Opportunity found chemical evidence in bedrock that a shallow salt water sea existed at some time in Mars' past. Spirit drilled into volcanic 10 rocks and found minerals suggesting they had been carried by water and collected in the lava's tiny pores as it hardened.
The editor of the Internet website Marstoday.com, Keith Cowing, says those discoveries alone justified 11 the mission.
"If they had both done that, or even if one of them had landed and still done that, it would have been considered a resounding 12 success," said Keith Cowing. "But these amazing little robots are still going."
Mars
Albert Haldemann says the inspection 13 of the bedrock has been key to understanding Mars' evolution. He notes that the layers in bedrock are a geological history book.
"When you find rock that is attached to the planet, that then tells you about the history of that place," he said. "We have done that now in detail in two places on Mars. That tells us that Mars is a diverse place, that there are significant differences on these two sides of the planet where the rovers are, that Mars has complex geology, not unlike Earth in that sense."
Since their early days, Spirit and Opportunity have roamed seven and 10 kilometers respectively past their original landing sites. Spirit is currently inspecting rocks and soils near a ridge 14 while its twin is exploring a crater with exposed rock layers that tell a longer span of Martian history than those it examined before.
Haldemann attributes their longevity 15 to careful ground control and good luck with Martian weather.
"Mars has been kind to these two rovers," he noted 16. "Both have had gusts 17 of wind blow dust off of solar panels at different times during the mission, and each time that has happened, it has cleaned the solar panels and basically reset 18 us as far as energy levels go, back to the beginning mission. That has been a new lease on life a couple of times for each rover."
The rovers are going about their work reinvigorated with new navigation software uploaded into their computers. One of the technicians who guides the rovers, Scott Maxwell, says the improvements have made them smarter and more independent.
"They are now better than they used to be at finding their way through fields of obstacles," he said. "They can keep an eye on something as they are driving and make sure that they get close to that particular thing because it is an interesting science target. They have figured out how to watch the skies for clouds or watch the terrain 19 for dust devils blowing by, and when they find those and they know those are interesting to us, to send back data on those. They have gotten smarter just as we have gotten smarter."
The rovers have some mechanical wear and tear, but nothing serious enough to stop them. Albert Haldemann says they have just survived another Martian winter and believes that if dust storms do not block the sun's energy and cause the batteries to die, they could last another 18 months until the next Martian winter.
- Geologists uncovered the hidden riches. 地质学家发现了地下的宝藏。
- Geologists study the structure of the rocks. 地质学家研究岩石结构。
- They're still plodding along with their investigation. 他们仍然在不厌其烦地进行调查。
- He is plodding on with negotiations. 他正缓慢艰难地进行着谈判。
- He was somewhat pompous and had a high opinion of his own capabilities. 他有点自大，自视甚高。 来自辞典例句
- Some programmers use tabs to break complex product capabilities into smaller chunks. 一些程序员认为，标签可以将复杂的功能分为每个窗格一组简单的功能。 来自About Face 3交互设计精髓
- The train derailed and plunged into the river. 火车脱轨栽进了河里。
- She lost her balance and plunged 100 feet to her death. 她没有站稳，从100英尺的高处跌下摔死了。
- A cocoon is a kind of silk covering made by an insect.蚕茧是由昆虫制造的一种由丝组成的外包层。
- The beautiful butterfly emerged from the cocoon.美丽的蝴蝶自茧中出现。
- With a telescope you can see the huge crater of Ve-suvius.用望远镜你能看到巨大的维苏威火山口。
- They came to the lip of a dead crater.他们来到了一个死火山口。
- It is not difficult to sketch the subsequent trajectory.很容易描绘出它们最终的轨迹。
- The path followed by a projectile is called its trajectory.抛物体所循的路径称为它的轨道。
- The water was too frigid to allow him to remain submerged for long.水冰冷彻骨，他在下面呆不了太长时间。
- She returned his smile with a frigid glance.对他的微笑她报以冷冷的一瞥。
- This warranty is good for one year after the date of the purchase of the product.本保证书自购置此产品之日起有效期为一年。
- As your guarantor,we have signed a warranty to the bank.作为你们的担保人，我们已经向银行开出了担保书。
- There have been several volcanic eruptions this year.今年火山爆发了好几次。
- 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。
- She felt fully justified in asking for her money back. 她认为有充分的理由要求退款。
- The prisoner has certainly justified his claims by his actions. 那个囚犯确实已用自己的行动表明他的要求是正当的。
- The astronaut was welcomed with joyous,resounding acclaim. 人们欢声雷动地迎接那位宇航员。
- He hit the water with a resounding slap. 他啪的一声拍了一下水。
- On random inspection the meat was found to be bad.经抽查，发现肉变质了。
- The soldiers lined up for their daily inspection by their officers.士兵们列队接受军官的日常检阅。
- We clambered up the hillside to the ridge above.我们沿着山坡费力地爬上了山脊。
- The infantry were advancing to attack the ridge.步兵部队正在向前挺进攻打山脊。
- Good habits promote longevity.良好的习惯能增长寿命。
- Human longevity runs in families.人类的长寿具有家族遗传性。
- 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。
- Her profuse skirt bosomed out with the gusts. 她的宽大的裙子被风吹得鼓鼓的。
- Turbulence is defined as a series of irregular gusts. 紊流定义为一组无规则的突风。
- As soon as you arrive at your destination,step out of the aircraft and reset your wristwatch.你一到达目的地，就走出飞机并重新设置手表时间。
- He is recovering from an operation to reset his arm.他做了一个手臂复位手术，正在恢复。