墨尔本PTE素材库—(Probably Not a) Giant Alien Antenna

(Probably Not a) Giant Alien Antenna

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没听懂？也没看懂？没有关系，这篇文章的确是有些难度啦！小编无意来打击大家信心哦~这篇短文的题材较为新颖，所以就拿来给大家过一遍啦！没听明白或者没看明白没关系，大家可以借助下面的key vocabulary list再看一遍Full Transcript，看自己这次是否能看明白了？

这段音频的主要内容是由于在宇宙间发现的一个比较神秘的信号，为啥神秘？因为它比我们已知的要亮上上百亿倍！这段短文中一些专业词汇，比如pulsar，比如antenna这类，大家能记个大概，或者能作为自己的阅读词汇就足够啦！没有必要去深究或者说硬要变成自己的写作和口语词汇哦~

澳大利亚语言学院会定期整理发布一些科学的短文，给大家用作PTE练习的素材。上至天文，下通地理，让自己英语能力提升的同时，也渐渐变成一个小学霸吧！

[Key Vocabulary]

Stud: Vt. 散布，用许多钮饰等装饰；n. 种马，大头钉

Telescope: n. 望远镜

Radiation: n. 辐射

Electromagnetic: adj. 电磁的

Astronomer: n. 天文学家

Stumble: Vt. 使… 困惑，使…绊倒

Mysterious: adj. 神秘的，不可思议的，难解的

Thousandth: adj. 千分之一的，第一千的

Theoretical: adj. 理论的，理论上的，假设的，推理的

Astrophysicist: n. 天体物理学家

Pulse: n. 脉冲，脉搏；Vt. 使跳动，Vi. 跳动，脉跳

Burst: Vt. 爆发，突发，爆炸；n. 爆发，突发，爆炸

Pulsar: n. 脉冲星

Antenna: n. 天线，触角，触须

Extra-terrestrials: n. 外星人；adj. 地球外的，大气圈外的

Precise: adj. 精确的，明确的，严格的

Stellar: adj. 星的，星球的，主要的

Standpoint: n. 立场，观点

Constraint: n. 约束，局促，态度不自然，强制

Beam:  n. 横梁，光线，电波，船宽；Vt. 发送，用…照射

Emitter: n. 发射器，发射体

Diameter: n. 直径

Alien: n. 外星人，外侨

Sailor: n. 水手，海员

Full Transcript

Astrophysicists propose that mysterious “fast radio bursts” could, in very speculative theory, be produced by an antenna twice the size of Earth. Christopher Intagliata reports.

The Earth is studded with telescopes, listening for electromagnetic radiation from the great beyond. And a decade ago, astronomers stumbled upon a mysterious signal: a powerful pulse of radio waves just a few thousandths of a second long. Mysterious because:

“What is the nature of the sources?” Avi Loeb, a theoretical astrophysicist at Harvard. Whatever the sources are, he says, “They seem to be brighter by 10 of billions of times more than the brightest radio sources we know about.”

The radio pulses are known as “fast radio bursts“—and Loeb says you’d need something tens of billions of times brighter than a pulsar to produce them. So he and his colleague Manasvi Lingam investigated another possibility: “We know of one simple way to produce very powerful radio waves, and that’s using a radio antenna.”

A radio antenna built and controlled by extra-terrestrials, to be more precise. Loeb and Lingam did the math on how big that stellar-powered radio antenna would have to be, to transmit signals like fast radio bursts. And whether it would even hold up from an engineering standpoint—like would it melt under its own heat?

Using those energy and engineering constraints, they found that the radio beam emitter would have to be twice the diameter of Earth. Pretty big—for us. But at least theoretically possible, he says, for more advanced civilizations. The study is in The Astrophysical Journal Letters. [Manasvi Lingam and Abraham Loeb, Fast Radio Bursts from Extragalactic Light Sails]

To be clear: this is definitely not proof that intelligent aliens exist. It’s just proof of concept, that someone, smarter than us, could in theory build such a thing. And why you might build it? “The idea is that an advanced technological civilization could produce a beam of radio waves focused on a sail that is pushing on the sail, such that eventually the sail will reach a fraction of the speed of light.” We’ll just have to see what arrives first: alien sailors, pushed by radio waves? Or the technological advances to allow us humans to build such a thing ourselves.

—Christopher Intagliata

(Source: https://www.scientificamerican.com/podcast/episode/probably-not-a-giant-alien-antenna/)