This could be a bit of a tricky (and amusing) situation for astronauts on board the International Space Station (ISS). Space Shuttle Discovery astronaut Mark Kelly mentioned a minor technicality with the new Kibo laboratory during an in flight interview last Friday: It might be too spacious. Surely this is a good thing right? It is, and it isn’t. On the one hand the lab provides a large volume for four astronauts to work in comfortably, but on the other hand, if you get stuck in the middle, you may not be able to reach the sides. This could result in a rather frustrating situation where one of the astronauts may become “stranded” in zero-G…
The brand new Japanese Kibo laboratory was successfully delivered to the ISS last Tuesday (June 3rd) by Space Shuttle Discovery (STS-124). After successfully attaching the large module to the station using the onboard robotic arm, the station astronauts connected the electrical, water and air supply, pressurized the module ready for use. This was all being done whist cosmonaut Oleg Kononenko carried out some essential plumbing on the station toilet pump.
So all is going well on board the ISS, especially with the prospect of carrying out some exciting new science activities inside the largest module of the station. However, the astronauts will have to be careful when inside Kibo, they might become stranded. As observed by STS-124 commander Mark Kelly last Friday, “You have to be a little extra careful, you can get out in the middle of it and you can’t reach a handrail and you could possibly get stuck there for a little while.”
The Kibo module is the largest module attached to the ISS. The laboratory measures 37 feet (11 meters) long by over 14 feet (4.3 meters) wide, should an astronaut drift into the middle of Kibo, he or she may not be able to reach the handrails or the sides. Kelly obviously had first-hand experience of this during the setup of Kibo as he said that he and his crew had little time for orbital antics, like flailing around in the middle of Kibo when work needed to be done.
This isn’t a serious issue as there will likely be more than one astronaut inside Kibo to assist should their crewmate get stranded. It also seems easy enough to stretch lengths of cord from one side of Kibo to the other (or one down the axis) so astronauts can quickly right themselves. But I’m sure that the station astronauts will be happy to have such a volumous space to float around in rather than being too worried about getting stuck in the middle…
Source: Reuters
They should equip the astronauts’ station suits with small membranes to be used as “wings”… 😉
Nah, just stretch a bungee cord or two across the middle of the widest open volume, so no one’s signifigantly out of reach of something to grab.
Heck, used the right way, it could even be fun…
I’m not sure how one could get stuck in the middle. If you floated to the middle somehow, you wouldn’t just stop. You would continue floating to the other side.
I suppose you could be in the middle hanging on to something, let go of it, and somebody could move it out of reach.
Interesting predicament. One that existed before with skylab, and one thats sure to come again if we plan any lofting other large structures into orbit.
Unlikely as the situation sounds maybe they should do some experiments while its still uncluttered in there.
I would bet that theres not much need for concern.
If a person cant move their body in such a way as to fan back towards a wall, the simple solution would be to keep a lapboard or something to flap with.
Fancier method would be to take a bottle of CO2 and a valve to use as a tiny thruster.
How about just compressed air. Then the CO2 scrubbers won’t have to deal with the extra carbon.
Something like a woopie-cushion or a latex balloon just came to mind! Print a Disney character on it and it could be called “science” >:)
Robert Heinlein already covered this in one of his stories. It seems that the individual who was stuck in the middle of a large space simply took off his shorts and threw them in one direction. Newton made sure he went in the opposite direction and eventually he got to where he wanted to be. (Never mind that just as he got to where he could grab onto something the space station manager’s wife came in and saw him in the buff.)
I was wonder how you could get “stuck” too, since you are unlikely to be completely motionless out of reach of the sides unless it was a deliberate act.
But then, what happens if you’re working at a console, then maybe you have to look up a manual or something, and when you look back up you had drifted slowly out of reach of the sides? You would eventually get to the other side, but it could be 10 minutes or more which, while not dangerous, would be a real drag!
No doubt this is really an inconvenience rather than a major issue, but I guess given how hard they work these people it’s something they want to avoid.
Helloooooo? We all have a nice little propulsion system. Just pucker up your lips and blow!
Meate Says:
June 10th, 2008 at 2:57 pm
“I’m not sure how one could get stuck in the middle. If you floated to the middle somehow, you wouldn’t just stop. You would continue floating to the other side.”
True, but you could slowly move out of reach of a wall without thinking about it or accidentally bump something and very–slowly–move–away. You wouldn’t be stuck, but you may be waiting a while to get to the other side!
Actually you *could* get stuck. Air exherts drag, remember? So if you detach from the wall very slowly, you may very well end up stopping in the middle of the module just due to the drag.
OTOH, as far as I know air in the space station is always moving around. I don’t know if there’s enough of a draft to carry an astronaut along in that situation of slow movement, but there may be.
And stop it with your ropes and bungee lines. My “wing” idea is way cooler! 🙂
Would just blowing air out of your mouth actually provide enough force to move a 90kg person faster than a hundredth of a millimeter per hour?
In a spaceship only a few feet across this is not a real issue. Theres probably a few ways to move yourself the two or three feet needed to grab something.
I think the concern begins when you’ve got a much larger structure. We’re looking at companies launching inflatable stations in the near future, with fewer size limits on interior volume.
Say you have a communal room thats over a hundred feet across then this issue could go from minor annoyance to something truly aggravating and (in the time sense) an expensive waste.
If you are forced build with a much smaller size limit in mind to avoid it, then the future of space will continue to be cramped just for efficiency.
You forget to mention fart power!
In this instance one couldn’t use the formula:
V(0)=V^2-2as
As the acceleration wouldn’t be a constant, unless of course one was extremely windy.
Newton’s Third Law does however apply.
Also assuming one didn’t pass out due to Oxygen depletion in the Kibo module, or suffer from toxic fume inhalation in the form of Methane.
One might also need to consider using after burner technology for extra thrust by igniting the gas with a lighter.
According to my calculations a sustained blast could carry one quite some distance – much like an ion drive.
Who said scientists didn’t have a sence of humour?
Also, once one’s natural gas supply has expired (as it inevitably will) the time/cost ratio of an Astronaut suspended in zero ‘G’ although moving toward one’s destination at minimal velocity, might justify the ignition of a secondary stage ‘solid rocket booster’ or firework to expediate the process.
🙂
Oh, c’mon! You just “swim” like in the water. Not as efficient but works basically just the same as the air does exert some drag. It would require a lot more flapping and swinging with the arms then in water so you would probably get a bit sweaty. It *could* be a problem in vacuum but that is unlikely to happen inside Kibo.
How about a kids sucker gun. Ie Spring power.
One can safely assume that if you deliberately attempt to get stuck in the middle, you can never do it. But its also a sure thing that it can and will happen without trying! Sort of like bouncing a golf ball off of a tree for a hole in one, throwing a balled up piece of paper into the trash can after bouncing it off of everything/anything and having it go in, or any number of fluke happenings that are sure things only when NOT attempting to do such a thing. (I usually claim I planned it anyway).
Not very scientific – but very true anyway.
**Would just blowing air out of your mouth actually provide enough force to move a 90kg person faster than a hundredth of a millimeter per hour?**
Apart from starting to spin head over feet if blowing straight forward, one could blow upwards toward a wall and move to the opposite wal. Can somebody do the math here? How fast can a 90 kg person propel himself by blowing as hard as he can?
Let’s try this – hopefully someone can check my reasoning. The human lungs can expel 4.8 litres from maximal inspiration to maximal expiration. We’ll use 4L to be safe. When repeated I can do about one maximal exhale every 4 seconds without fainting. That makes an average flow of 1 L/sec.
The article at http://lib.bioinfo.pl/pmid:17542834 makes reference to the air velocity of a cough being 10 m/sec and a sneeze being 50 m/sec. Let’s say a maximal exhale through puckered lips is about midway between those at 30 m/sec(that’s about what it feels like to me).
A few different sites give the weight of 1 L of air at about 1.2 g. So repeatedly, maximally blowing at full force through puckered lips provides a constant force of about (0.0012g/s)(30m/s) = 0.036 N.
That’s enough to accelerate a 90kg (200lb) astronaut at 0.4mm/s^2. Each exhale would accelerate you by 1.6 m/s.
Really when you think about it air doesn’t have much mass, and you’re only accelerating a small amount with each breath. You can push far more air around (and thus moving you faster) by flapping a clipboard.
small battery operated personal cooling fans would do the trick
don’t they put velcro in appropriate locations so you can hang without floating off?
Thank you, Cecil!
You said “Each exhale would accelerate you by 1.6 m/s.” Does that mean that with one exhale (along the length axis of the body) would move the astronaut 1.6 m in one second? One blow would do the trick quite well, wouldn’t it?
Tickle your nose… 🙂
Well, yes, Hemal, I can imagine if you sneeze you make a firm tumble in 0-grav! So a firm “blowing at full force through puckered lips” with your head held upwards should put your feet on the other wall in a sec.
Can you confirm that, Cecil?
I’m not sure if anyone watched the first opening of the KIBO lab last week on NASA TV…but for a few minutes after it was first opened, the astronauts were just kinda lounging around inside of the lab…Garrett Reisman demonstrated what we’re talking about here perfectly! he was literally stuck in the middle, out of reach of anything to help him to the side…
he did eventually reach something…after a series of flips and stretches…it was actually kind of funny to watch! im sure its not on youtube, but i still have it on my DVR…i suppose i should try to get it here to show everyone, even if its not top quality…
Ahh just blow a few times or flap your arms as if swimming.
Sure it wont be fast, but you would get to the other side.
If you get into the centre of the KIBO coming in from any side, you will continue to move to the opposite side, due to the conservation of momentum.
And if some curious fate happens to bring your momentum to zero just as you reach the centre of the lab, Alex has given the right solution to solve that problem: blow for a few times, and then wait a half a minute.
Regards
Günther
I have seen no mention of the orbiting of the shuttle and the space station orbiting while be docked together. A local radio station announced on Monday ( 6/9/08) that It was seen on Sunday evening and could been seen again on the 9th. over the Arizona skies traveling from NW toward SE. I live in central Arizona and did observe at the approx, time and the direction he had stated. We have heard nothing on TV nor can we find ref. on the web. Can you help?
Drummeo
“I’m not sure how one could get stuck in the middle. If you floated to the middle somehow, you wouldn’t just stop. You would continue floating to the other side.”
It’s not like moving through vacuum. If you started out slowly enough, air friction could well bring you to a stop, out of reach of anything to grab. The larger the pressurized volume, the mor easily this could happen.
‘Swimming’ through air is possible, of course, but with your hands alone, it would be less efficent than in water.
One of the things I imagine trying, had I the opprotunity, is to see if those little battery powered, hand-held fans could be effective personal propeller engines inside a pressurized, weightless enclosure.
That could also evolve into a weightless sport, much as Heinlein and Ruzic have already said about wings in a Lunar habitat…
I wonder what might happen if somebody gets into a fast spin in the middle.
Kibo is huge…so overnight the Japs will have the biggest, and most scientifically significant, component of the station? Very impressive, or ambitious…sounds like they may have a controlling interest from now on…
A simple device with a rare earth magnet and a retractable cord – like vaccum cleaner cords, or a tiny mouse for laptops.
It could fit into a very small and unobtrusive pouch on the belt, or around the ankle with velcro.
Pull out a length, set the spring to lock, and toss it to something magnetic.
If aluminium and other non-magnetic synthetics are used throughout, it would be simple to glue brightly coloured, very thin steel targets in strategic locations.
They could carry collapsable pointers (like a collapsable antenna; just modify so it locks when extended so it doesn’t collapse easily), in a pocket, and use it in case of emergency.
Extend it when needed and use it to push against a stationary object to get going again. Simple $2.50 solution.
Hehehe, or they could use silly string as a projectile.
I think they should use electro magnet active clothing so they can drift toward preset metal handrails around the cabin.,It would also be cool to have objects drift to you like inkpens and clipboards.
Didn’t Skylab have a larger interior than Kibo? I don’t remember any astronaut getting stuck in the middle of Skylab.