一九六九年六月。兩個航班和國民警衛(wèi)隊空軍戰(zhàn)機的飛行員報告稱,他們受到一隊不明飛行物的侵擾。其中一個人估計,發(fā)光的不明飛行物距離他們只有幾百英尺。戰(zhàn)機飛行員甚至宣稱他們發(fā)生了近距離的擦撞。
What were these UFOs really? It turned out theywere fragments of a meteor coming apart in the upper atmosphere. Now here's the mostinteresting part: the meteor fragments were at least one hundred and twenty five miles fromthe planes. How could you possibly think something over a hundred miles away was about to hityou?
這些不明飛行物到底是什么?原來,它們是來自高空大氣層中的流星碎片。有趣的是,流星碎片距離飛機至少有一百二十五公里。你能想像得到一百多英里之外的東西可以撞到你嗎?
Objects in the sky confuse our perceptual abilities. With no visual cues to help calculatedistance, our brains rely on size and speed instead. How? By using a simple fact: far-awaythings look like they are going slower than close-up things. You may have noticed this whendriving: those distant phone poles pass sluggishly while the ones on the road go zooming by. Ina blank white sky, our brains default to a simple strategy: the bigger it looks and the faster itgoes, the closer it probably is.
天空中的物體能夠混淆我們的感知能力。沒有視覺線索來幫助計算距離,我們的大腦只能依賴于物體的尺寸和速度。怎么依賴?這有一個簡單的事實:遠距離物體看起來比近距離物體的移動速度要慢。當你駕駛汽車時,你可能注意到了這樣的事實:那些遙遠距離的電話桿掠過車窗的速度很緩慢。在空曠的天空,我們的大腦默認了一個簡單概念:物體體積越大,速度越快,它可能就距離我們越近。
This is a smart way to proceed, and it generally works. Still, our perception can be fouled byrare situations in which we find ourselves looking at something far away that neverthelessmoves extremely fast, such as an incoming meteor. At thousands of miles an hour, thatflaming object speeds across your field of vision, and your brain can easily conclude it must bemuch closer than it is--maybe even about to abduct you.
這種推理方式很聰明、也很有效。盡管如此,在罕見的情況下比如當我們看到遠處高速移動的物體(例如流星碎片)時,我們的感知能力仍然會受到影響。但一個發(fā)光物體以數千英里的時速劃過你的視野時,你的大腦可以很容易地得出這樣的結論:它距離我太近了——可能是要綁架我。