時(shí)差N小時(shí):當(dāng)天空變成綠色時(shí)
這聽起來就像是個(gè)童話故事。
If you look at the horizon at sunset–exactly as the last sliver of sun disappears–you might see aflash of brilliant green blaze across the sky.
日落的時(shí)候如果你看看地平線，尤其是在太陽的最后一縷銀光消失的時(shí)候，你可能會(huì)看到一束耀眼的火焰劃過天空。
Indeed, an old Scottish proverb maintains that whoever sees this flash will always be lucky inlove. 的確，有一句古老的蘇格蘭諺語這么說，看見這道光焰的人總是會(huì)在愛情上交好運(yùn)。
While we can't confirm the lucky-in-love part of this, there is a scientific explanation for theflash of green light.
盡管我們無法證實(shí)會(huì)有桃花運(yùn)，但對(duì)于這束綠光倒有一個(gè)科學(xué)的解釋。
As sunlight enters our atmosphere, it bends slightly.
當(dāng)陽光進(jìn)入大氣層，光線會(huì)發(fā)生輕微的彎曲。
This is due to refraction, the same thing that makes a pencil look slightly askew when youstick it half way into a glass of water.
這是折射的作用，就象把鉛筆的一半插入一玻璃杯水中，鉛筆會(huì)看起來有點(diǎn)傾斜。
The atmospheric bending of light rays is greatest when the sun is right along the horizon, atsunrise or sunset.
日出日落時(shí)分，太陽恰好貼著地平線的時(shí)候就是光線折射作用最強(qiáng)的時(shí)候。
How does bending sunlight create a green flash?
但彎折的太陽光又是怎樣產(chǎn)生綠光的呢?
When sunlight is bent by refraction, it separates into different colors, just like light through aprism.
當(dāng)日光由于折射而彎曲時(shí)，光線就會(huì)分解成不同的顏色，就像通過棱鏡發(fā)射不同的光一樣。
While a prism can make a dramatic rainbow, atmospheric refraction isn't that strong.
然而三棱鏡可以折射出漂亮的七色彩虹，而大氣的折射作用卻沒有那么強(qiáng)。
It doesn't turn the sun into a rainbow, but it makes the lowest part of the sun seem a bitmore red, and the top of the sun seem greenish blue.
它不會(huì)將太陽光折射成彩虹，但是它可以使最底部的光變得更紅一些，而最頂部的光看上去像藍(lán)綠色。
The effect is so subtle, you'd never notice it.
這個(gè)變化非常微妙，你可能從來都未曾注意。
Except, of course, at sunset or sunrise.
當(dāng)然，除了在日出或日落的時(shí)候。
For a split second, when most of the sun's globe is below the horizon, the only part showing isthat blue-green sliver along the top.
只有那么一瞬間，當(dāng)太陽的大部分輪廓低于水平線，僅有的露出來的部分就是頂部的藍(lán)綠色長條。
Blue light is scattered by the atmosphere, so what's left is a brief flash of green, the onlyillumintion in the sky!
藍(lán)光被大氣層分散，剩下的就是一縷縷的綠光，天空唯一的光亮處。
Please remember, this happens immediately after a sunset. Never look directly at the settingsun.
請(qǐng)記住，這種現(xiàn)象只在日落后的一瞬間發(fā)生。要記著可別一直盯著落日看。
