选择城市
新东方网为大家带来2020托福听力练习：宇宙藏宝图寻找外星生物（下载），希望对大家有所帮助!更多内容请随时关注新东方网!
Carl Sagan once referred to our home planet as a mote of dust suspended in a sunbeam."
And that poetic description holds true for a lot of exoplanets, too.
In fact one of the simplest ways we detect exoplanets is by looking at their sunbeam…and measuring how it dims, ever so slightly, as the exoplanet passes across it, called a transit.
Which raises an interesting question:
"Thinking about extraterrestrial observers—which of them would observe the Earth, moving across our own sun?"
Ralph Pudritz, a theoretical astrophysicist at McMaster University in Canada.
He and his colleague Rene Heller quantified the narrow band of space from which any observers on other worlds would be able to see the Earth transiting the sun.
And they determined that this line of sight would be a plane just half a degree thick,but that cuts through a slice of our galaxy that's estimated to contain 100,000 sunlike stars… along with their companion planets.
The analysis is in the journal Astrobiology.
Pudritz and Heller suggest that hunters of extraterrestrial life may want to listen particularly closely for signals originating at star systems within that narrow band of galactic sky.
They say that advanced civilizations there may have already detected us using the transit method, and may now be sending us a message.
You might think of this paper, then, like a treasure map, for intelligent life.
"We don't know if there's treasure out there of course, right?
You never know that about a treasure map.
But it's a good place to look.”
翻译见下页
卡尔·萨根曾经将我们所生活的地球称为晨空中飞扬的一粒尘埃。
而这种诗意般的描述对很多太阳系外行星也同样适用。
事实上我们探测太阳系外行星最简单的方法之一就是观察它们散发的光束，并且即使十分微弱，也会对光的衰减情况进行测量，因为随着运动，太阳系外行星经过太阳的时候会衰减。
太阳系外行星.jpg
而这就引出一个有趣的问题:考虑下外星观察者们—当我们的地球越过太阳的时候，会是怎样的一种观察方式呢?
加拿大麦克马斯特大学的天体物理学家拉斐尔·普德里兹提出了这样的质疑。
他和他的同事莱内·海勒将任何地外观察者能够观测到地球通过太阳的宇宙窄带空间进行了量化。
结果他们确定这条狭长带是一个只有半度厚的平面结构，但却能够穿过一片连同其同伴行星在内我们的银河系，这其中包含100000个太阳般大小的恒星。
这项研究已在《天体生物学》杂志上发表。
普德里兹和海勒建议寻找外星生命的专家也许需要特别密切留意银河系那狭带中的恒星系统发出的原始信号。
他们表示高等文明也许已经用这种方法获知到我们的存在，现在也许正给我们发信息呢。
你也许想到这篇研究对寻找智能生命就像一张藏宝图一样。
我们当然不知道宝藏是否存在，对吧?
你从来都没见过那张藏宝图。
但去一探究竟也不错。
1.refer to 指称;引用
例句:I mention this point now in passing and shall refer to it again.
这一点现在顺便提一下，以后还会讲到。
2.think about 想一想
例句:I'll have a think about that.
我会考虑考虑的。
3.along with 随着
例句:I'll go along with you.
我将随同你一起去。
4.cut through 穿过
例句:It took firemen two hours to cut through the drive belt to free him.
消防员花了两个小时才把传动带切断，把他救了出来。
以上是新东方网为大家带来的2020托福听力练习：宇宙藏宝图寻找外星生物（下载），希望认真积极的备考，早日取得优异的成绩。更多内容请随时关注新东方网!
最新热文推荐：
更详细的内容请点击：2020软科世界一流学科排名发布
