美国国家公共电台 NPR Get Ready For the Next Big Thing In NASA's Search For Earth's Twin

 

LULU GARCIA-NAVARRO, HOST:

Tomorrow, a rocket is scheduled to blast off with a NASA satellite. It's a planet hunter that will spend two years looking for alien worlds. NPR's Nell Greenfieldboyce reports on how it will help scientists in their quest to find another Earth.

NELL GREENFIELDBOYCE, BYLINE¹: Mercury, Venus, Earth, Mars, Jupiter, Saturn², Neptune³, Uranus⁴. For a long time, those were the only planets scientists knew about. In recent years, beyond our solar system, they've discovered over 3,000 more, thanks in large part to a NASA mission called Kepler.

GEORGE RICKER: The most exciting things we've learned from Kepler has been that planets are extremely common. There are far more planets in the Milky⁵ Way than there are stars.

GREENFIELDBOYCE: That's George Ricker, an astronomer⁶ at MIT. He says Kepler was really good at finding planets but not ones that scientists could study in detail.

RICKER: There's really not much more we can say other than that they exist.

GREENFIELDBOYCE: And that is very unsatisfying because after all, what scientists really want to do is find another planet like our own, one that some form of life could call home. I asked Sara Seager, also at MIT, how close we are to finding Earth's twin.

SARA SEAGER: Far. We're very far from knowing that something is like Earth out there.

GREENFIELDBOYCE: That's why she and Ricker are part of a team that's working on NASA's next mission called TESS, for Transiting⁷ Exoplanet Survey Satellite. TESS will scan almost the entire sky, looking for telltale signs of planets around closer, brighter stars. This will make it easier for scientists to do follow-up measurements.

SEAGER: And so with the planets that TESS finds, we're going to be able to use a different set of telescopes and then try to find out if any of them are indeed somewhat like Earth.

GREENFIELDBOYCE: She says the goal is to find small, probably rocky planets orbiting in a sweet spot around the star that's not too hot and not too cold. Those planets could be studied using a big, new space telescope that NASA is supposed to launch in a couple years. It could analyze⁸ the planet's atmospheres.

SEAGER: The most important thing I think would be to find signs of water vapor⁹ in a small planet atmosphere because all life as we know it needs liquid water.

GREENFIELDBOYCE: Astronomers¹⁰ are excited by the idea that tests will give them a massive new catalog of relatively¹¹ easy-to-study planets beyond our solar system. The follow-up work is sure to go on for years. Ruth Angus is an astronomer at Columbia University.

RUTH ANGUS: If we detect life signatures on any extrasolar planet in the next ten years, then that planet will almost certainly have been discovered by TESS.

GREENFIELDBOYCE: But she says that's a big if because there's reason to think the planets found by TESS might not be super-cozy little places. The mission will mainly be targeting planets orbiting small common stars called red dwarfs¹². And red dwarfs are known to send out scorching¹³ blasts of ultraviolet and X-ray radiation that could fry any life. Still, Angus says she's skeptically hopeful.

ANGUS: There are certain conditions that we need for the life that we're familiar with. But who knows if those conditions apply across the galaxy¹⁴?

GREENFIELDBOYCE: She says they've got to start looking somewhere, and TESS will tell them where. Nell Greenfieldboyce, NPR News.

1 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。

2 Saturn   

n.农神，土星

参考例句：

• Astronomers used to ask why only Saturn has rings.天文学家们过去一直感到奇怪，为什么只有土星有光环。
• These comparisons suggested that Saturn is made of lighter materials.这些比较告诉我们，土星由较轻的物质构成。

3 Neptune   

n.海王星

参考例句：

• Neptune is the furthest planet from the sun.海王星是离太阳最远的行星。
• Neptune turned out to be a dynamic,stormy world.海王星原来是个有生气、多风暴的世界。

4 Uranus   

n.天王星

参考例句：

• Uranus is unusual because it is tilted.天王星非常特殊，因为它是倾斜的。
• Uranus represents sudden change and rebellion.天王星代表突然性的改变和反叛。

5 milky   

adj.牛奶的，多奶的；乳白色的

参考例句：

• Alexander always has milky coffee at lunchtime.亚历山大总是在午餐时喝掺奶的咖啡。
• I like a hot milky drink at bedtime.我喜欢睡前喝杯热奶饮料。

6 astronomer   

n.天文学家

参考例句：

• A new star attracted the notice of the astronomer.新发现的一颗星引起了那位天文学家的注意。
• He is reputed to have been a good astronomer.他以一个优秀的天文学者闻名于世。

7 transiting   

通过（transit的现在分词形式）

参考例句：

• The effect of the transiting mechanic required reserve system vehicle is low. 准备金制度的传导机制的作用是很低的。
• I was busy transiting to the telescope. 我正忙着旋转望远镜。

8 analyze   

vt.分析，解析 (=analyse)

参考例句：

• We should analyze the cause and effect of this event.我们应该分析这场事变的因果。
• The teacher tried to analyze the cause of our failure.老师设法分析我们失败的原因。

9 vapor   

n.蒸汽，雾气

参考例句：

• The cold wind condenses vapor into rain.冷风使水蒸气凝结成雨。
• This new machine sometimes transpires a lot of hot vapor.这部机器有时排出大量的热气。

10 astronomers   

n.天文学者，天文学家( astronomer的名词复数 )

参考例句：

• Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
• Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪，为什么只有土星有光环。 来自《简明英汉词典》

11 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。

12 dwarfs   

n.侏儒，矮子（dwarf的复数形式）vt.（使）显得矮小（dwarf的第三人称单数形式）

参考例句：

• Shakespeare dwarfs other dramatists. 莎士比亚使其他剧作家相形见绌。 来自《简明英汉词典》
• The new building dwarfs all the other buildings in the town. 新大楼使城里所有其他建筑物都显得矮小了。 来自辞典例句

13 scorching   

adj. 灼热的

参考例句：

• a scorching, pitiless sun 灼热的骄阳
• a scorching critique of the government's economic policy 对政府经济政策的严厉批评

14 galaxy   

n.星系；银河系；一群(杰出或著名的人物)

参考例句：

• The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
• The company has a galaxy of talent.该公司拥有一批优秀的人才。