A really fun question is that when astronauts are in space

一个很有趣的问题是 宇航员在太空中的时候

they're not experiencing gravity, so how does digestion work?

没有重力 那消化系统是如何工作的呢？

We sort of think of food moving down in our bodies,

我们觉得食物在身体中一路向下

it seems that maybe gravity would have something to do with that.

肯定多少与重力有些关系

The amazing thing is that it really doesn't and this was one of the first things we discovered

意外的是 其实根本不是这样 我们先把动物后把人类送入太空中时

when we sent animals first and then people up into space.

最先发现的就是这一点

Some people wondered if you could swallow, if you could digest at all without the force of gravity.

有人会疑惑 在没有重力的情况下 人能否吞咽 能否消化

And it turns out that the act of peristalsis, the way your throat and your intestines squeeze themselves,

事实表明 蠕动动作 咽喉和肠道的运动方式

will actually move food and water through your digestive system without gravity at all

会把食物和水送入消化系统 完全不需要重力

and you can even test that with people lying in hospital beds.

看一下躺在医院病床上的人们 你就能验证这一点

When you think about somebody that's actually lying down,

想想那些平躺着的人

there's no force of gravity that's pulling food in one direction or the other.

并没有重力牵引着食物朝一个或另一个方向前进

The human body is actually pretty good at moving food through without the force of gravity.

人类身体其实很擅长在没有重力的情况下运送食物

Now other part of this is what happens when the food comes out the other end,

另一方面是 当食物从身体的另一端出来时会发生什么

because this is a natural thing that all humans do every day.

这是所有人每天都做的稀松平常的事

Well, you've now reached the wonderful science of space toilets.

现在 你谈论的就是太空马桶这一精彩的科学领域了

They actually act with suction.

其实它们靠的是吸力

Now if you've ever been to the dentist's office and the dentist wants you to spit

如果你看过牙医 牙医让你往外吐水的时候

and he holds up a little cup with a tube attached to it

他会拿一个带有管子的小杯子

and there's suction that takes the water down the tube.

会有吸力把水从管子里抽下去

A space toilet acts very much that way;

太空马桶的工作原理跟它很像；

there's suction, there's a current of air that actually draws the waste down so it can be disposed of.

有吸力 有一股空气把废弃物吸下去进行处理

And, honestly, sometimes it doesn't work perfectly.

说实话 有时候它也会出故障

This is one of the things that astronauts have to deal with.

这是宇航员必须应对的一种情况

When you think about the word 'floater', that has happened, where something escapes and you need to go get it.

想想“漂浮者”这个词 这种情况确实发生过 是指有些东西漂走了 你得抓住它

Some of the worst parts of human space flight in the very early days,

很早的时候 人类在太空飞行中会遇到一种很糟的情况

like in Gemini all the way back in the 1960s,

比如上世纪60年代的双子飞行

was people would collect their urine in a little plastic bag and sometimes they broke.

那就是人们把自己的尿液收集在小塑料袋里 有时候袋子会破

So there have been some people up there and some very bad circumstances.

所以那时太空中的人会遇到一些非常糟糕的情况

Today, the toilet on the space station works very well and suction brings everything down

现在 空间站里的马桶非常好用 吸力会把所有东西都吸下来

and the best thing I can compare it to is the dentist's spit cup.

我能把它比作的最好的东西就是牙医的口水杯

They actually have a little video camera

其实他们还安装了小摄像机

so you can see if anything is floating around in the toilet before you get up. Yeah.

让你在起来之前能看到马桶里是否还有漂浮物 对