What is dust made of? - Michael Marder

翻译人员: Xinran Yu 校对人员: Carol Wang

Meet Dermatophagoides farinae.

见识一下美洲尘螨，

Crawling around on eight legs,

它用八只脚四处爬行，

this creature has no eyes to appreciate the kaleidoscope of colors around her.

这种生物是没有眼睛的， 无法欣赏其周边环境的色彩斑斓。

She relies on her extraordinary sense of smell

它依靠超凡的嗅觉，

to lead her to food and safe places to lay eggs.

去找食物以及产卵的安全地方。

And she’s smaller than a pinhead.

它比针头还小。

Dermatophagoides farinae is a dust mite.

美洲尘螨是一种尘螨，

Less than a tenth the size of an ant,

体型不到一只蚂蚁的十分之一，

a dust mite’s whole world is contained in the dusty film under a bed

尘螨的生活的世界就在 一张床下或者一个被遗忘角落

or in a forgotten corner.

的薄薄灰尘之中。

This realm is right under our noses, but from our perspective,

尘螨的王国就在我们眼皮底下， 但在我们看来，

the tiny specks of brilliant color blend together into a nondescript grey.

这些色彩艳丽的微粒 集中在一起却是单调的灰色。

What are these colorful microscopic particles?

这些色彩斑斓的微小粒子是什么？

What distinguishes the dust in your house from, say, sand on a beach

房间里的灰尘与海滩的沙 的区别在于，

is that it is a mixture of many different ingredients.

灰尘中包含了许多不同物质。

It can contain grains of sand,

它包含沙粒、

dead skin cells,

死亡的皮肤细胞、

tiny hairs and threads,

微小毛发和线头、

animal dander,

动物毛屑、

pollen,

花粉、

manmade pollutants,

人造污染物、

minerals from outer space,

来自外界的矿物质，

and, of course, dust mites.

当然，还有尘螨。

Dust mites eat animal dander,

尘螨会吃动物毛屑、

human skin,

人类皮肤，

and some fungi.

以及一些霉菌。

We shed dead skin cells constantly,

我们经常会有 死亡的皮肤细胞脱落，

and wherever we live, they mix into the household dust.

不论我们住在哪里，它们都会 和家中的灰尘混合在一起。

The same goes for our pets:

我们的宠物也是这样：

their dander and hairs enter the mix,

它们的皮屑和毛发都会混和进去，

as do tiny pieces of thread and cotton fibers from our clothes.

我们衣物上的小线头 以及棉纤维也会混和进去。

These components make every household’s dust

这些成分会让每户人家的灰尘

a unique blend of bits from its particular inhabitants.

都成为了来自住户独特的混合灰尘。

Household dust also contains substances that blow in from the wider world.

家中的灰尘也包含了 从外界吹进来的物质。

Depending on the local geology,

根据当地的地质情况而异，

finely ground quartz, coal, or volcanic ash

微细的石英粉、煤，或火山灰

might enter the air as atmospheric dust,

都可能会以大气灰尘的形式 进入空气当中，

along with pollen and fungal spores.

并伴随着花粉以及菌类孢子。

Industrial activities also contribute cement powder,

工业活动也产生水泥粉末、

particles from car tires,

来自汽车轮胎的微粒，

and other chemicals to the airborne mix.

以及其他化学物质， 这些都会混合在空气中。

The combination of these elements can be as unique as a fingerprint.

这些元素的组合就像 指纹一样独一无二。

In Spain, where the land is rich in carbonate materials,

在西班牙，土地富含碳酸盐物质，

dust contains 20 times as much calcium as dust in Nigeria,

那里灰尘中的钙含量 是地质情况截然不同

where the geology is quite different.

的尼日利亚的二十倍。

After a particularly violent storm,

在一场特别的强烈暴风之后，

scientists identified dust from the Sahara Desert

科学家在伦敦依靠独特成分

thousands of miles away in London,

辨识出了数千里之外

based on its specific composition.

的撒哈拉沙漠尘土。

In the future,

在未来，

we may be able to pinpoint the origins of dust samples even more specifically,

我们有可能更明确地 定位出灰尘样本

down to a particular neighborhood or even house -

是属于哪个社区， 甚至哪间房子——

something that may be of great help for forensic specialists.

这可能会对法医很有帮助。

In addition to markers of humans, animals, and landscapes,

灰尘所含的粒子， 除了来自人类、动物和环境之外，

dust also contains particles from further afield.

还可能来自更远的地方。

When a star explodes in a distant galaxy,

当一颗恒星在遥远的星系爆炸时，

super hot gases vaporize everything nearby.

高温气体会蒸发附近的所有物质。

Then, the dust settles; minerals condense out of the gas.

接着，尘土会沉积下来； 气体凝结成矿物质。

Floating out there between planets and galaxies,

这些在行星和星系之间漂 浮的外星尘埃

this extraterrestrial dust contains tiny pieces of extinguished stars

包含了已经消失的恒星的微小碎片，

and the building blocks of future celestial bodies.

以及形成未来天体的基石。

Every year, tens of thousands of tons of cosmic dust

每年，数万吨的宇宙尘土

lands on Earth and mingles with terrestrial minerals.

降落在地球上， 与陆地矿物质混合在一起。

This blend of chemicals, minerals, and intergalactic particles

这种化学物质，矿物， 以及银河间粒子的混合物

settles out of the air onto surfaces in our homes,

会从空气中沉积下来， 落在房屋表面，

mixing with the detritus of each house’s occupants.

与房屋中的居住者 产生的碎屑混合。

Stars explode,

星星会爆炸，

mountains erode,

山脉会被侵蚀，

and buildings, plants, and animals

建筑物、植物，及动物

are all slowly but surely pulverized into fine grey powder.

都会无可避免地 慢慢地变成灰色粉末。

We’re all destined to become dust,

我们都注定要化为尘土，

but it’s also possible that we came from it.

但我们也有可能 是来自于尘土。

Interstellar dust has been found to carry organic compounds through space.

我们已经发现，星际尘土 会带着有机复合物穿过太空。

It’s possible that billions of years ago,

有可能在数十亿年前，

some of these cosmic particles were the seed of life

某些宇宙粒子正是我们在

on our little blue planet.

这蓝色小星球上的生命种子。