在太空中能不能打嗝？

Hanging about in space can do pretty strange things to the human body, which is poorly adapted to life without gravity. It can create a slew of health problems, keeping clean is a huge hassle, and doing a wee is majorly awkward.

人类的身体并不适应无重力的环境。生活在外太空会引发一系列的健康问题，而保持清洁卫生也成为了巨大的麻烦，即使是小便，都需要完成一整套令人尴尬的流程。

But is it true, as a Snapple cap asserts, that you can't burp?

但是，据说，宇航员在太空中是不能打嗝的，这是真的吗?

This is the question one Twitter user posed to former International Space Station (ISS) Commander Chris Hadfield late last week, and received a surprising answer: it's true, kinda.

一位Twitter用户上周末向前国际空间站(ISS)指挥官克里斯·哈德菲尔德Chris Hadfield提出了上述问题，并得到了一个令人惊讶的回复：真的，至少部分是。

You can't burp in space - at least not like you do here on Earth.

你不能在太空中打嗝——至少不能像你在地球上那样来。

"You can't burp in space because the air, food and liquids in your stomach are all floating together like chunky bubbles," Hadfield replied on Twitter.

“你不能在太空中打嗝，因为你胃里的空气、食物和液体就像大团泡沫一样漂浮在一起。”哈德菲尔德在推特上回答道，

"If you burp, you throw up into your mouth. So guess where the trapped air goes?"

“如果你打嗝，你会把它们一起吐出来。所以猜猜，你要怎么排出肚子里的空气?”

Air can, of course, travel from your stomach and out through your mouth in space. But the problem is the lack of gravity. Here on Earth, when you have gas trapped in your stomach, it rises to the top because it's lighter than the food and stomach juices in there.

当然，空气可以经腹部挤压，从食道通向嘴巴。但问题出在无重力环境上。在地球上，如果你的胃里有气体时，它会上升到顶部，因为它比那里的食物和胃液要轻。

In space, where there is no gravity, the gas doesn't rise to the top. It stays mixed in with all the other stuff that's in your stomach - like the below video, an ISS experiment that involved putting an effervescent tablet in coloured water.

在没有重力的太空中，气体不会上升。它与你肚子里的所有其他东西混合在一起 。

So, if the gas wants to come out of your mouth, it brings that other stuff with it. It's sort of a cross between a burp and a spew.

所以，如果胃里空气想要从你的口中出来，它会带着其他的东西。在太空里，打嗝和呕吐之间的界限消失了。

"When one burps in space, it is often a 'wet burp' which means some liquid is expelled," NASA engineer Robert Frost explained on Quora in 2016. "It's kind of like acid reflux."

“当一个人在太空打嗝时，通常是‘湿嗝’，这意味着一些液体被排出，”美国宇航局工程师罗伯特·弗罗斯特在2016年在Quora上解释道。这有点像酸反流。”

This rather unpleasant experience has also been called a 'bomit', which should give you some idea of exactly how horrible it is. Imagine having it happen in a spacesuit.

这种相当不愉快的经历在地球上也被称为“呕吐”。想象一下，它发生在密封的宇航服里，那是何等可怕的场景。

There are further problems. You don't necessarily want all that gas going out the other end, either. The space station is a small, enclosed environment, and therefore can get pretty smelly.

此外，还有其他问题。你也不一定希望肚子里所有的气体都从消化系统的另一端排出。空间站是一个逼仄封闭的环境，因此气味可能会很糟糕。

In the 1960s, scientists conducted experiments to determine which space diet would produce the least farts, because - wait for it - flammable butt gas was deemed a hazard in a pressurised cabin.

在20世纪60年代，科学家们进行过实验，找出产生屁最少的食物来当作宇航员的口粮，因为屁中的易燃成分可能会造成不必要的危险。

Apparently beans and other high-flatulence foods such as cabbage and Brussels sprouts were subsequently removed from the spaceflight menu, although green beans and broccoli are now included.

显然豆类和其他高胀气食物，如卷心菜和布鲁塞尔豆芽，立即从航天飞行菜单中被删除，而之后，黑名单里又加进了绿豆和西兰花。

And there is actually air circulation on the ISS to keep astronauts from suffocating on their own CO2 exhalations, so farts get moved away, too.

国际空间站里实际上有空气循环净化设备，以防止宇航员因二氧化碳含量过高而窒息，因此屁也会被抽走。

If you do end up going to space, there was one enterprising astronaut who found a way to belch without bomiting. According to the book What's it Like in Space? by Ariel Waldman, NASA astronaut and physicist Jim Newman, who has spent 43 days in space, developed what he called the "push and burp."

如果你的梦想是成为一名宇航员，请不要因为不能打嗝而焦虑。一位有进取心的宇航员找到了一种方法。根据沃尔德曼Ariel Waldman撰写的书籍《在外太空中生活》中披露，美国国家航空航天局宇航员兼物理学家吉姆纽曼Jim Newman在太空中度过了43天，他发明了他所谓的“推式打嗝法”。

"He found that by pushing off a wall, he could create a force in lieu of gravity that kept his food down in his stomach, giving him a brief chance at expelling gas without consequence," Waldman wrote.

“他发现通过推开墙壁获得反冲，可以创造一种代替重力的效果，将食物留在胃里，使他获得一个短暂的时间窗口来打一个嗝，而不至于引发糟糕的后果。”沃尔德曼写道。

Astronauts are certainly brilliant people.

宇航员果然都是人中翘楚。