美国国家公共电台 NPR--NASA's InSight Mars lander may shut down soon. Here's what it's achieved so far

NASA's InSight Mars lander may shut down soon. Here's what it's achieved so far

Transcript¹

NASA's InSight probe landed on Mars in 2018 to help scientists study the planet's interior. But Martian dust has been building up on InSIght's solar arrays, which could end its mission.

LEILA FADEL, HOST:

For nearly four years, a NASA spacecraft has been studying Mars. The InSight lander is sitting near the red planet's equator. Now it's running out of power and could die as soon as next month. This isn't a surprise to mission managers, though. They'd expected Martian dust would build up on the probe's solar panels. Now it has, and panels can no longer generate the electricity needed for normal operations. NPR's Joe Palca has this report on what InSight has accomplished² since it landed in 2018.

JOE PALCA, BYLINE³: InSight's main scientific goal was to record marsquakes, the Martian equivalent of earthquakes, using an instrument called a seismometer. Northwestern University planetary scientist Suzan van der Lee says it took a leap of faith to base the success of the mission on recording⁴ marsquakes because...

SUZAN VAN DER LEE: Before the InSight mission, we had no idea that there were even going to be marsquakes.

PALCA: InSight principal investigator⁵ Bruce Banerdt was sure there would be - at least pretty sure.

BRUCE BANERDT: For the first two months, we did not see a single marsquake. And I was starting to get a little bit nervous at that point. You know, I was checking my email day after day - nothing yet, nothing yet.

PALCA: So it was a great relief to Banerdt and the rest of the team when, in March 2019, four months after landing, InSight did record a quake - and many more since.

BANERDT: By now we've been on Mars for about 3 1/2 years. We have over 1,300 quakes in our calendars.

PALCA: Unlike Earth, Mars doesn't have tectonic plates grinding together to cause rumbles⁶. Suzan van der Lee says now that scientists know for sure Mars has quakes...

VAN DER LEE: We can start figuring out what kind of marsquakes these are, what kind of mechanisms⁷ are behind them.

PALCA: In addition to figuring out what's causing them, scientists can use the quakes to probe the interior of the planet. The seismic⁸ waves generated by the quakes have different patterns depending on what kind of material they're traveling through. Brown University's Ingrid Daubar says the seismometer can also measure the vibrations⁹ caused when meteorites¹¹ crash into the planet.

INGRID DAUBAR: We thought that we would detect maybe a few to tens of meteorite¹⁰ impacts on Mars just from their seismic signals.

PALCA: But for the first two years, nothing. Finally, three impact craters¹² were detected during InSight's third year on Mars. Cameras aboard a satellite orbiting Mars confirmed new craters appeared where the seismic signals said the impacts should be. As it reaches the end of its mission, InSight principal investigator Bruce Banerdt says it's fair to call InSight a success.

BANERDT: We've definitely accomplished all the things we set out to do with the one exception that our heat flow experiment was a disappointment.

PALCA: The heat flow experiment was supposed to use a special probe to measure heat flowing from the planet's interior. But to do that, the probe had to bury itself 15 feet below the surface, and no matter what commands they sent, the probe wouldn't stay buried. Banerdt says they're not sure why. Mars had one other surprise for the InSight team. When they listened closely, they could hear a faint hum coming from Mars - yes, I said hum.

BANERDT: And it seems to be there all the time, you know, day and night. And we really have been, you know, scratching our heads and trying to figure this out.

PALCA: You don't think maybe it's just a giant in the core of Mars snoring or something like that?

BANERDT: (Laughter) Maybe. Or a giant swarm¹³ of underground bees buzzing.

PALCA: Probably not. But we'll certainly let you know if that turns out to be the answer.

Joe Palca, NPR News.

1 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。

2 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。

3 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。

4 recording   

n.录音，记录

参考例句：

• How long will the recording of the song take?录下这首歌得花多少时间？
• I want to play you a recording of the rehearsal.我想给你放一下彩排的录像。

5 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。

6 rumbles   

隆隆声，辘辘声( rumble的名词复数 )

参考例句：

• If I hear any rumbles I'll let you know. 我要是听到什么风声就告诉你。
• Three blocks away train rumbles by. 三个街区以外，火车隆隆驶过。

7 mechanisms   

n.机械( mechanism的名词复数 )；机械装置；[生物学] 机制；机械作用

参考例句：

• The research will provide direct insight into molecular mechanisms. 这项研究将使人能够直接地了解分子的机理。 来自《简明英汉词典》
• He explained how the two mechanisms worked. 他解释这两台机械装置是如何工作的。 来自《简明英汉词典》

8 seismic   

a.地震的，地震强度的

参考例句：

• Earthquakes produce two types of seismic waves.地震产生两种地震波。
• The latest seismic activity was also felt in northern Kenya.肯尼亚北部也感觉到了最近的地震活动。

9 vibrations   

n.摆动( vibration的名词复数 )；震动；感受；（偏离平衡位置的）一次性往复振动

参考例句：

• We could feel the vibrations from the trucks passing outside. 我们可以感到外面卡车经过时的颤动。
• I am drawn to that girl; I get good vibrations from her. 我被那女孩吸引住了，她使我产生良好的感觉。 来自《简明英汉词典》

10 meteorite   

n.陨石；流星

参考例句：

• The meteorite in Jilin Exhibition Hall is believed to be the largest in the world.吉林展览馆的陨石被认为是世界上最大的。
• The famous Murchison meteorite smashed into the Australian ground in 1969.1969年著名的默奇森陨石轰然坠落在澳大利亚。

11 meteorites   

n.陨星( meteorite的名词复数 )

参考例句：

• Small meteorites have left impact craters all over the planet's surface. 这个行星的表面布满了小块陨石留下的撞击坑。 来自《简明英汉词典》
• One theory about the existence of extraterrestrial life rests on the presence of carbon compounds in meteorites. 地球外存在生命的理论是基于陨星上存在碳化合物质这一事实的。 来自《简明英汉词典》

12 craters   

n.火山口( crater的名词复数 )；弹坑等

参考例句：

• Small meteorites have left impact craters all over the planet's surface. 这个行星的表面布满了小块陨石留下的撞击坑。 来自《简明英汉词典》
• The battlefield was full of craters made by exploding shells. 战场上布满弹坑。 来自《现代英汉综合大词典》

13 swarm   

n.(昆虫)等一大群；vi.成群飞舞；蜂拥而入

参考例句：

• There is a swarm of bees in the tree.这树上有一窝蜜蜂。
• A swarm of ants are moving busily.一群蚂蚁正在忙碌地搬家。