大多數(shù)人都聽過這樣的說法：不存在兩片完全相同的雪花。但是，每年冬天的一場場降雪中，都會有無數(shù)雪花飄落，這樣的說法真的正確嗎？

Most people have heard the saying that no two snownflakes are identical. But with countless snownflakes produced in every winter flurry, could such a thing be ture?

根據(jù)紐約布羅法大學(xué)的化學(xué)家、晶體專家杰森.本尼迪克特的說法，答案是肯定的！

Well, according to Jason Benedict, a chemist and crystal expert at the University at Buffalo in New York, the answer is yes!

這是因?yàn)?，雪花由大量的水分子組成，而這些水分子彼此相連，通常以灰塵或污垢為中心進(jìn)行凝結(jié)?？茖W(xué)家將這一中心稱為凝結(jié)核。

This is because snowflakes are made of tons of water molecules that have became linked to one another, usually forming around a central point of dust or dirt. Scientists call this nucleation.

“所以就形成了這么一個極小的微觀異物，”本尼迪克特說，“從而使得水分子有所依附?！?/p>

“So there's this teeny, tiny microscopic foreign object,” said benedict, “and that gives water molecules something to hold onto.”

這些冰晶形成的形狀是多種因素共同作用的結(jié)果，包括溫度、濕度和氣壓----所有的這些因素會隨著風(fēng)吹動而不斷變化。因此，想要使得一片雪花中的每一個水分子與另一片中的完全處于同一位置，這樣的可能性極小。

The shape these ice crystal take as they form is the result of many factors, including temperature, humidity and air pressure -- all of which are constantly shifting and changing as the winds blow. This makes the likelihood that each water molecule in that snownflake would sit in exactly the same place as each water molecule in another snownflake extremely unlikely.

本尼迪克特說，“這種情況就不可能會出現(xiàn)?！?/p>

“It just won't happen, ” Benedict said.