美国国家公共电台 NPR--25 years later, looking back on the accomplishments of the Mars Pathfinder

25 years later, looking back on the accomplishments² of the Mars Pathfinder

Transcript³

More than two decades ago a small probe carrying an even smaller rover landed on Mars. Pathfinder and the Sojourner⁴ rover paved the way for sophisticated robotic explorers that have landed since 1997.

RACHEL MARTIN, HOST:

It was a long shot that proved successful in the end. Twenty-five years ago today, a mission on Mars ended.

(SOUNDBITE OF ARCHIVED RECORDING)

UNIDENTIFIED PERSON: Scientists at NASA's Jet Propulsion Laboratory in Pasadena, Calif., have lost contact with the Pathfinder lander on Mars and are afraid the mission may be over.

MARTIN: Pathfinder's mission was only supposed to last one month. In fact, it lasted almost three. It was remarkable⁵ in many respects from the way it landed on Mars to the people who chose to work on the project. Science correspondent Joe Palca covered the Pathfinder mission for NPR. He visited the Jet Propulsion Lab recently and has this look back at the historic accomplishment¹.

JOE PALCA, BYLINE⁶: Before Pathfinder, the only other time NASA successfully landed on Mars was in 1976, when the two Viking missions touched down. The Vikings were flagship missions supported by lots of engineers and technicians and buckets of money. By comparison, Pathfinder was built on a shoestring⁷, part of NASA's faster, better, cheaper mantra at the time. It had a small team of engineers and scientists, and it used technologies that had never been tried. Many old hands at JPL shied away from the project, thinking it would never succeed. Even some of the people who did work on it were skeptical⁸.

JENNIFER HARRIS TROSPER: We weren't sure it was going to work. I really, truly was in the camp of this may or may not work.

PALCA: Jennifer Harris Trosper was one of the young engineers on the project. Only 29 at the time, she was a flight director on landing day. She says a small team working against the odds⁹ gave the project some advantages. Everybody had a get-it-done attitude.

HARRIS TROSPER: That's just how it was. You just - you found whatever the problem was, and you got the right people, and you solved it, you know, as good as you could in the time that you had.

PALCA: She nearly didn't work on Pathfinder at all. She came to JPL straight out of college, but then decided¹⁰ to take a leave from the lab.

HARRIS TROSPER: I went over to the former Soviet¹¹ Union - now Sevastopol, Ukraine, in the Crimea - and I taught English.

PALCA: After a while, though, she had second thoughts about leaving JPL.

HARRIS TROSPER: There was one point in time when I was, like, eating a cold chicken leg at an outdoor cafe, drinking beer at 9 a.m. in the morning. And I thought, what have I - am I ever going to get back to America? What have I done with my life?

PALCA: So she let some people at JPL know she was interested in coming back.

HARRIS TROSPER: My phone rang one day, and it was Joe Savino. He's like, hey, Jennifer, you want to do this new job? Nobody wants to take it. It's on this new mission. I can't get anybody to take it. You want to take it? I'm like, sure. I need a job.

PALCA: Another young engineer who joined the project was Rob Manning. Like Trosper, Manning's background didn't necessarily prepare him for Pathfinder. He knew a lot about electronics and software.

ROB MANNING: But I really didn't know anything about parachutes. I didn't know about heat shields. I really didn't know much about, you know, the mechanics of flying through space.

PALCA: Pathfinder was going to use a simple but untried landing system. As it plunged¹² into the Martian atmosphere on landing day, the probe would still rely on a heat shield and parachutes and small rockets to do most of the slowing, but then it was going to smack¹³ into the Martian surface, protected only by airbags, and bounce like a giant beach ball until it finally came to rest. Manning was in charge of the landing sequence. When we spoke¹⁴ earlier this month, we were in the Space Flight Operations building. I asked if this was where he was on landing day.

MANNING: Yes, I was upstairs, right above us in our little control room, surrounded by glass - a small group of us, maybe 10 of us in the room.

PALCA: NASA brass¹⁵ stood outside. Network television cameras peered through the glass. The tension was off the charts. Nobody knew if the airbag scheme was going to work. Manning says there was only one way to know for sure whether Pathfinder touched down safely.

MANNING: I could hear on my audio set voices from Spain.

PALCA: Outside of Madrid, there's a giant radio telescope. JPL had sent Sami Asmar to Spain so he could use that antenna¹⁶ to listen for a signal from Pathfinder. The control room at JPL could hear Asmar, and he could hear the control room.

SAMI ASMAR: I could sense that they were very nervous. The time has come for the spacecraft to kind of announce itself, and there was a slight delay.

MANNING: No signal. And then...

ASMAR: I think I see a weak signal, and it's coming in and out. And that's when I heard an explosion of cheers and cries.

(CHEERING)

PALCA: Success.

(CHEERING)

PALCA: Yes, there was joy. But Manning says for an engineer responsible for designing the mission and building the spacecraft, there was something else, too.

MANNING: The real reason we're cheering is that we're relieved because up until that moment, we're constantly thinking about what was it we forgot to do? What didn't we check? What didn't we see? How - where did we go wrong?

HARRIS TROSPER: Yeah, it was certainly relief, but for me it was elation¹⁷, and I swear I feel that way every single time we land something successfully on Mars. But then the other piece of it that I experienced with Pathfinder that was unique and the first-time experience for me was this idea that we were the first ones there in this other place in our solar system exploring.

PALCA: Both Trosper and Manning stayed on at JPL and worked on other successful Mars missions. Manning is now chief engineer at JPL, and Trosper is his deputy. He says there's been a shift in the way missions are developed and tested.

MANNING: In the past, we worried about - that the thing breaks.

PALCA: Now the hardware is reliable, but controlling that hardware, writing the code to make it work has become more and more complex. And it's tricky¹⁸ to even know when you've made an error. And in the days of Pathfinder, at least some on the team knew how each system on the spacecraft worked - maybe not in intimate detail, but in general how they worked individually and together. That's gone.

MANNING: And today, we can't hold our systems in our heads anymore. It's - they're far bigger than any human being can comprehend. It's just too many things inside, and our brains aren't big enough to hold it.

PALCA: Since we're not likely to grow bigger brains, it's going to take some new strategies to manage these complex missions. And in a way, each time a mission succeeds, the pressure mounts. Success is no longer an ambitious dream. It's an expectation. But then, despite the pressure and the complexity¹⁹, both Trosper and Manning seem to think the reward is worth it.

Joe Palca, NPR News.

(SOUNDBITE OF MUSIC)

1 accomplishment   

n.完成，成就，（pl.）造诣，技能

参考例句：

• The series of paintings is quite an accomplishment.这一系列的绘画真是了不起的成就。
• Money will be crucial to the accomplishment of our objectives.要实现我们的目标，钱是至关重要的。

2 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》

3 transcript   

n.抄本，誊本，副本，肄业证书

参考例句：

• A transcript of the tapes was presented as evidence in court.一份录音带的文字本作为证据被呈交法庭。
• They wouldn't let me have a transcript of the interview.他们拒绝给我一份采访的文字整理稿。

4 sojourner   

n.旅居者，寄居者

参考例句：

• The sojourner has been in Wales for two weeks. 那个寄居者在威尔士已经逗留了两个星期。 来自互联网
• A sojourner or a hired servant shall not eat of it. 出12:45寄居的、和雇工人、都不可吃。 来自互联网

5 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。

6 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

7 shoestring   

n.小额资本；adj.小本经营的

参考例句：

• In the early years,the business was run on a shoestring.早年，这家店铺曾是小本经营。
• How can I take the best possible digital pictures on a shoestring budget?怎样用很小投资拍摄最好的数码照片？

8 skeptical   

adj.怀疑的，多疑的

参考例句：

• Others here are more skeptical about the chances for justice being done.这里的其他人更为怀疑正义能否得到伸张。
• Her look was skeptical and resigned.她的表情是将信将疑而又无可奈何。

9 odds   

n.让步，机率，可能性，比率；胜败优劣之别

参考例句：

• The odds are 5 to 1 that she will win.她获胜的机会是五比一。
• Do you know the odds of winning the lottery once?你知道赢得一次彩票的几率多大吗？

10 decided   

adj.决定了的，坚决的；明显的，明确的

参考例句：

• This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
• There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。

11 Soviet   

adj.苏联的，苏维埃的；n.苏维埃

参考例句：

• Zhukov was a marshal of the former Soviet Union.朱可夫是前苏联的一位元帅。
• Germany began to attack the Soviet Union in 1941.德国在1941年开始进攻苏联。

12 plunged   

v.颠簸( plunge的过去式和过去分词 )；暴跌；骤降；突降

参考例句：

• 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。

13 smack   

vt.拍，打，掴；咂嘴；vi.含有…意味；n.拍

参考例句：

• She gave him a smack on the face.她打了他一个嘴巴。
• I gave the fly a smack with the magazine.我用杂志拍了一下苍蝇。

14 spoke   

n.（车轮的）辐条；轮辐；破坏某人的计划；阻挠某人的行动 v.讲，谈（speak的过去式）；说；演说；从某种观点来说

参考例句：

• They sourced the spoke nuts from our company.他们的轮辐螺帽是从我们公司获得的。
• The spokes of a wheel are the bars that connect the outer ring to the centre.辐条是轮子上连接外圈与中心的条棒。

15 brass   

n.黄铜；黄铜器，铜管乐器

参考例句：

• Many of the workers play in the factory's brass band.许多工人都在工厂铜管乐队中演奏。
• Brass is formed by the fusion of copper and zinc.黄铜是通过铜和锌的熔合而成的。

16 antenna   

n.触角，触须；天线

参考例句：

• The workman fixed the antenna to the roof of the house.工人把天线固定在房顶上。
• In our village, there is an antenna on every roof for receiving TV signals.在我们村里，每家房顶上都有天线接收电视信号。

17 elation   

n.兴高采烈，洋洋得意

参考例句：

• She showed her elation at having finally achieved her ambition.最终实现了抱负，她显得十分高兴。
• His supporters have reacted to the news with elation.他的支持者听到那条消息后兴高采烈。

18 tricky   

adj.狡猾的，奸诈的；(工作等)棘手的，微妙的

参考例句：

• I'm in a rather tricky position.Can you help me out?我的处境很棘手，你能帮我吗？
• He avoided this tricky question and talked in generalities.他回避了这个非常微妙的问题，只做了个笼统的表述。

19 complexity   

n.复杂(性)，复杂的事物

参考例句：

• Only now did he understand the full complexity of the problem.直到现在他才明白这一问题的全部复杂性。
• The complexity of the road map puzzled me.错综复杂的公路图把我搞糊涂了。