時差N小時:外星人來電

Suppose one day scientists pick up a transmissionthey think isgenerated by aliens.

假如有一天，科學(xué)家收到到外星人發(fā)來的信號該怎么辦呢?

Now what? Do we build a landing strip andbreak outthe welcome wagon?

我們有建造飛碟起落跑道來歡迎它們嗎?

Well here's the thing about picking up alienbroadcasts.

關(guān)于接收到外來廣播的事情是這樣的。

The receivers scientists are currently using to listento space noise are designed to find constantsignals,or signals that are pulsing at regular intervals.

科學(xué)家接者收目前會聽航天噪音，然后找出不變信號或者找出那些常規(guī)跳動的信號。

But any message carried by these signals wouldprobably be lost because the receivers can't pickup the modulation, or rapid variations, in thebase signal.

但是任何攜帶信息的信號都可能丟失，因為接收者在信號基地不能收集到變調(diào)或快速變化的信號。

The SETI institute, which searches for extra terrestrial life, has compared picking up asignal'smodulation to picking up the sound of a flute when it's masked by the noise of a waterfall.

對外星智能的探索研究院，專門尋找外星生物。它他們對接受到信號的變調(diào)和被瀑布聲掩蓋的笛聲做了比較。

Luckily, scientists would still have enough data to pinpoint where in the sky the transmissioniscoming from.

幸運(yùn)的是，科學(xué)家們有足夠的數(shù)據(jù)來確定信號廣播的位置。

And any slow changes in the broadcast frequency would reveal information aboutthe rotationand movement of the aliens' planets.

廣播頻率的細(xì)微變化都會揭露外星人星球的旋轉(zhuǎn)和運(yùn)動情況。

Okay, but how will we know if they are friendly?

我們怎樣才知道那些是友好的信號呢?

Well, If we ever do detect a transmission, thiswould be huge news.

如果我們發(fā)現(xiàn)了外來廣播，那就是很大新聞了。

The government would definitely allocate funds to building largerinstruments capable ofpicking up signal modulations.

政府一定會撥款建造更大的儀器，能夠接受信號變調(diào)。

However, even once scientists are able tomeasure the modulation, it isn't certain that we'll beable to understand the message.

不管怎樣，即使科學(xué)家能夠測量變調(diào)，也不能確定我們能明白這些信息。

I guesseveryone's hoping that if the aliens are anything like us, they'll send simple pictures andeasy-to-decode messages.

我想每個人都希望外星人與我們多少有點相似之處，會發(fā)簡單的圖畫和容易解碼的信息。