@Clayton C. Anderson, A NASA astronaut who lived and laughed in space for quite a while! 的回答
Becoming detached from the International Space Station (ISS) during an EVA (spacewalk) is a low probability occurrence. While not likely to happen, since it is possible, astronauts prepare for it.
For each and every spacewalk, one of the first –and most critical– steps occurs before ever departing the station’s airlock. With hatches still closed and locked, astronauts verify their individual safety tethers (85 foot braided steel cable w/retractable reel) are appropriately “closed and locked” on their spacesuits. In addition, while inside the station’s “porch,” the two spacewalkers hook their safety tethers together, in a move we call the “daisy chain.” Now, both astronauts are connected to each other, and one of them is also anchored firmly inside the station.
每次太空行走，第一步也是最重要的一步，就是在离开空间站的气闸之前， 在舱门仍处于关闭和锁定状态的情况下，宇航员确认其各自的安全绳（带可伸缩卷轴的85英尺编织钢缆）已适当地“关闭并锁定”在其太空服上。 另外，在空间站的“门廊”中，两个太空行走者将安全绳拴在一起，我们称之为“菊花链”。 现在，两位宇航员已经相互连接，其中一位也被牢固地固定在空间站内。
When the hatch finally opens, another critical procedure is executed. The lead spacewalker –EV1– will exit the airlock headfirst and attach the other (free) end of their safety tether to an anchor point outside. Now, the two still-daisy-chained astronauts are anchored inside and out. At this point, EV1 will break the daisy-chain and hook partner EV2’s safety tether to the external anchor point. Now both crewmembers are safely, and separately, anchored externally.
当舱口最终打开时，将执行另一个关键过程。 太空行走的领队–EV1–将首先离开气闸头部，并将其安全绳的另一端（自由端）连接到外部的锚点。 现在，两个仍然被菊花链束缚的宇航员被固定在里面和外面。 此时，EV1将断开菊花链，并将搭档EV2的安全绳钩到外部锚点。 现在，两个机组人员都安全且分别地锚定在外部。
Exiting the ISS airlock, for my first EVA July 23, 2007.
It is now time for the still-inside EV2 astronaut, to disconnect his/her internal anchor point and exit the hatch. Voila! Two spacewalkers, each safely anchored outside the ISS, ready to go to work.
现在是时候让仍在里面的EV2宇航员断开他/她的内部锚点并离开舱口了。 瞧！ 两名太空行走者，每个都安全地锚定在国际空间站外面，准备工作了。
All of that effort may still not be enough if proper “tether protocol” is not exhibited by our brave spacefarers throughout the spacewalk. As they both move away from the airlock –anchor points still firmly attached– each must endeavor to keep their individual 85′ lines separate and untangled, a task that seems simple, but isn’t always so, during a 6.5 hour excursion outside in a micro-gravity environment. In addition, if the worksite is more than 85′ away from the starting point, additional safety tethers must be carried with them, and “tether swaps” must be appropriately/safely executed as needed.
如果我们勇敢的航天员在整个太空行走中没有表现出适当的“系绳协议”，那么所有这些努力可能仍然不够。 当他们都离开气闸时-锚点仍然牢固地固定-每个人都必须努力保持各自的85’线分开且不缠结，这项任务看似简单，但在空间站外微重力环境中行走6.5个小时实际上却并不容易。 此外，如果工作地点距离起点超过85’，则必须随身携带其他安全系绳，并且必须根据需要适当地安全执行“系绳交换”。
Yet I haven’t really answered your question have I? If all of our “tether protocol” efforts still fail us (remember, this is an extremely low probability), and one of us totally detaches from the ISS structure, we will be ready, albeit a tad bit embarrassed.
While unlikely to fall all the way to earth as your question suggests, it is possible the rates imparted to a spacewalker who has lost physical contact with the station could be high. The resulting drift away from “home” and deeper into outer space would not be good. Rescue by another spacecraft would be futile, taking too long to undock, rendezvous, and capture the wayward astronaut. Another option was required.
虽然不太可能像你问题所说的那样一路跌落到地球，但宇航员在物理上脱离空间站后却可能有很高速度。 由此产生的远离“家”的漂泊并进入外层空间将是不好的。 让另一艘太空船营救将是徒劳的，要花费很长时间才能脱离，会合并捕获乱飘的宇航员。 需要另一个选择。
The solution? It’s pretty amazing. Like Buck Rogers, we have a jetpack attached to our suits and unlike Mr. Rogers, we have virtual reality (VR) to train for this exact scenario.
解决方案？ 太神奇了，与巴克·罗杰斯（Buck Rogers）一样，我们的宇航服上也装有喷气背包，与罗杰斯先生不同，我们有虚拟现实（VR）可以针对这种情况进行训练。
With Rick Mastracchio, performing a VR Lab session in preparation for STS-131.
The training venue is called the VR Lab –original huh?! Home to the true geniuses behind the DOUG (Dynamic Onboard Ubiquitous Graphics) software system, we are trained to utilize our last resort –the Simplified Aid for EVA Rescue (SAFER) backpack– in a virtual world.
培训场所称为VR实验室-原来是吗？ 这是DOUG（ Dynamic Onboard Ubiquitous Graphics ，动态舱载通用图形）软件系统背后的天才的家园，我们受过训练，可以在虚拟世界中，利用我们的最后手段-简单的EVA救援（SAFER）背包。
Images from NASA’s VR Lab at the Johnson Space Center (JSC) in Houston, Texas.
Wearing special gloves and helmets creates a virtual world enabling a simulated “fall” from the station, where repetition is key to a safe return. Since the SAFER is our last resort, we must be ready to correctly deploy its hand controller (HC) and “fly” ourselves back to structure. Fly is a general term. In essence, we must learn to utilize and understand the nuances of orbital mechanics to get our EVA suit spaceship, back to the ISS spaceship. Practice makes perfect. We see the ISS virtually, and our inputs to the hand controller coupled with the software’s execution, give us a video game of sorts that imitates what we would experience in space. As our ability to return safely progresses, we “fall off” with higher and higher rates, until we can consistently demonstrate that we can save ourselves repeatedly.
戴上特殊的手套和头盔会创建一个虚拟的世界，使人们能够从空间站“模拟”掉落，而重复是安全返回的关键。 由于SAFER是我们的最后选择，因此我们必须准备好正确部署其手动控制器（ hand controller ，HC），并让自己“飞回”空间站。 飞是一个通用术语。 从本质上讲，我们必须学会利用和理解轨道力学的细微差别，通过控制宇航服来让我们回到ISS宇宙飞船。 实践出真知。 我们看到了虚拟的ISS，而我们对手动控制器的输入，以及软件的执行程序，使我们获得了一种可以模拟在太空中体验的视频游戏。 随着我们技术的提高，我们将以越来越高的速度“脱离”空间站，直到我们始终如一地证明，我们无论什么情况下都能救回自己。
It was FUN to be an astronaut! Keep lookin’ up!
@ Jasmine Adamson Super friendly aviator
Thank you Mr. Anderson, for taking the time to educate the masses. It is SO cool to hear from real astronauts on this subject! I still remember when I shook John Glenn’s hand and I was 7 or 8 years old. You inspire people, and I just wanted to let you know I really appreciate it!
谢谢安德森先生，感谢您抽出宝贵的时间来教育群众。 看到真正的宇航员回答这个问题真是太酷了！ 我仍然记得当我和John Glenn握手时，我才7，8岁。 您激励着人们，我只是想让您知道我非常感激！
You are very, very welcome Jasmine! I have a lot of fun writing down my answers. I am thinking of publishing a book of all my quora writings. Thoughts?
很不错， Jasmine ！ 写下答案很有趣。 我正在考虑出版一本有关我在Quora上所写的答案的书。 有什么想法吗？
@ Jasmine Adamson Super friendly aviator
I think that would make a great coffee table style book. Maybe put some nice big space photos on each page with your blurbs running down the side. I would totally buy that! I think that would appeal to a large audience for sure. I worked in aerospace for a while and there’s so many “little” things like this which are absolutely fascinating, and go way beyond how astronauts pee, which I’m sure is still the most common question you get 🙂
我认为这本书很适合在咖啡桌之类的地方阅读。 也许在每页上放一些漂亮的大空间照片，然后您的回答一路写下来。 我肯定会买那个！ 我认为那肯定会吸引大批观众。 我在航空航天领域工作了一段时间，有很多这样的“小”事情绝令人着迷，而不仅仅是宇航员如何小便，但我敢肯定，这仍然是您最常遇到的问题：）
For geeks like me, an extremely technical book would have some appeal, but I think that might be hard to sell to the masses.
@ Noam Kaiser Daddy, Israeli, VC Intel Capital. Top Writer 2014-2017
I’m just so happy you’re on Quora.
I’m happy I’m on Quora too! And happier that I have followers like YOU! ;0)