If you wipe a finger across a household surface that hasn’t been cleaned in the last few days, chances are you’ll come into contact with dust. Look around and you’ll find the stuff everywhere, from the particles floating in a sunbeam to the fine layer of grime coating TV screens, bookshelves, and car dashboards.
如果你用手指在几天没打扫的家具上一划，你的手指很可能会碰到灰尘。环顾四周，你会发现灰尘无处不在，从光线中漂浮的微粒到电视机表面、书架以及汽车仪表盘上覆盖的那层细细的尘垢。
What Is Dust?
什么是灰尘？
Dust comes from everything and, like death and taxes, you can’t avoid it. When things–shoes, rocks, plants, socks, anything at all–begin to break down, they release tiny pieces of themselves into the air.
任何东西上都有灰尘，就如同死亡和税收，你逃也逃不掉。鞋子、岩石、植物、袜子，任何东西开始分解的时候，它们就会释放出细微的粉尘到空气中。
These countless bits settle everywhere, and because matter is always coming apart, dust production is a never-ending business.
这些数不清的微粒到处都是，因为物质在不断地分解，所以灰尘的产生也是永不停歇的。
Dusty
尘垢
In a typical household, dust consists mainly of things such as dead insect parts, flakes of skin, food particles, and shreds of fabric. But not all dust is the product of natural decay; we create amazing quantities of dust everyday.
在一个典型的家庭中，灰尘主要由这些东西组成：如死亡的昆虫尸体、皮屑、食物的颗粒以及衣服的碎屑。但是，不是所有的灰尘都是自然衰变的产物；我们每天都在创造数量惊人的灰尘。
For example, a single puff of a cigarette contains an estimated four billion large dust particles. Industry of all sorts, from the sawing of a piece of wood to large-scale steel manufacturing, creates particular kinds of dust. In short, dust is all around, even in the air we breathe.
例如，仅仅是抽烟时吐出的一口烟就包含了大约40亿个大的灰尘微粒。所有工业，从锯一块木头到大范围的钢铁制造，都会产生特定种类的灰尘。简而言之，灰尘无处不在，甚至存在于我们呼吸的空气中。
Because its particles are so small, dust is highly mobile. Westward winds regularly blow dust from the Sahara desert across the Atlantic and into the atmosphere above American coastal towns, where it contributes to some thrilling sunsets.
灰尘微粒非常细小，所以它们的流动性很大。西风携带着撒哈拉沙漠里的尘土跨越大西洋来到美国沿海城市的上空，也为这些城市带来了扣人心弦的日落。 |