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by akira2501 926 days ago
> Do the conditions of being in orbit have any sort of preservation effect?

There's no reason to suspect they would. Even so, it is unlikely we could ever take advantage of this in any meaningful or efficient way.

> Do the microbes that help break it down exist?

Almost certainly. They're in excrement and the astronauts are allowed to bring some personal effects on board. Speaking of excrement, on Apollo, they didn't have an advanced toilet, so they just used bags. Apparently, they were instructed to seal the bag after adding an antibacterial agent, for fear of them eventually inflating from decomposition products and then popping.

Also.. quick search shows that ISS astronauts after 6 months to a year have _more_ bacteria on their skin and _might_ be why astronauts experience higher levels of inflammation in general.

Finally, let me drop my favorite ISS fact here, if you're doing work outside the ISS that requires turning a wrench, you must turn it _very_ slowly, less than 1 full turn per minute, because the low gravity environment means the ISS as a whole weighs next to nothing and vibrational modes from wrenching can setup very easily. This fact is specifically flagged in several spacewalk manuals.

3 comments

> Finally, let me drop my favorite ISS fact here, if you're doing work outside the ISS that requires turning a wrench, you must turn it _very_ slowly, less than 1 full turn per minute, because the low gravity environment means the ISS as a whole weighs next to nothing and vibrational modes from wrenching can setup very easily. This fact is specifically flagged in several spacewalk manuals

Can you point me to a resource where I can read more about this? The closest thing I could find was an article from 1998 that stresses the importance of being tethered while wrenching so that you rotate the bolt, rather than the bolt rotating you: https://www.csmonitor.com/1998/1204/120498.us.us.3.html

edit: I still can't find anything explaining this, but I did find https://msis.jsc.nasa.gov/sections/section14.htm and https://www.nasa.gov/wp-content/uploads/2009/07/143159main_s... which suggest bolt-driving power tools are used during spacewalks (which presumably get more than 1 RPM)

It's like being a gyroscope for an instant... which the space station also has?
I also am skeptical of this claim. I mean, if you've got solid mechanical connection to the ISS as in you don't spin when you use the wrench, you shouldn't impart momentum. It would be the same thing if you did the wrenching _inside_ the station as well.
I've been looking for it, but NASA apparently likes to fully wipe any historical documentation off their site once every few years. After 20 minutes of this, I'm sorry to say, I'm way to frustrated to continue. I can't believe NASA is still this bad at holding onto history. Would a redirect have killed them?

It was in a single STS missions space walk manual. It was the literal "sequence of events" manual. It had the timeline for the entire mission, the absolute procedure for every single movement, down to where to put your feet, which handrail number you were to grab with your hands, and where exactly your tethers where to be for each movement.

The case I remember reading had to do with unbolting and replacing a piece of equipment. If my memory serves me correctly it had to do with the cooling system and either an upgrade or maintenance replacement.

In that specific section, it had a small note, for the astronaut and for their handler on board, about the maximum rate at which the bolt could be wrenched. It specifically called out vibration throughout the station as a particular factor. this may have been related to the position of the equipment, which should have been on one of the solar and cooling support spars, and not directly on a habitat module.

Anyways, it stuck in my mind because as I started reading the document, it just kept getting into deeper and more specific detail about every single aspect of the mission, when I finally arrived at the bolt movement section, I was completely taken aback. I wish I would have had the good sense to archive it for myself.

If you've got the time and better skills that my outdated google fu, you should be able to track it down. I want to say STS130 or STS135. Good luck. Let me know if you find it please.

Wouldn't those vibrational modes be damped by the mass rather than the weight of the ISS? Because the same goes for any other interaction between the ISS and its occupants, torquing down a bolt is no different from anything else. The biggest worry would be to upset the orientation of the entire ISS but I'm assuming that you are going to be tethered and/or connected to the ISS, if you didn't it would be you that spins rather than the ISS due to the difference in relative mass.
> There's no reason to suspect they would. Even so, it is unlikely we could ever take advantage of this in any meaningful or efficient way.

What about the higher levels of radiation impacting mold growth?