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What happens when you wring out a washcloth in space
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All the comments and stories posted to Hacker News that reference this video.⬐ eridiusI thought just watching the microphone float in front of him was interesting enough. I was totally not prepared for the awesomeness of the wrung-out washcloth.⬐ sksksk⬐ robotmayI always wonder, if you spend a length of time in space, you must get used to being able to leave an object in mid air, go do something, and go back and pick it up later.When astronauts come back to earth, do they have some adjusting period where they keep dropping items on the floor because they forget about gravity?
⬐ NegativeK⬐ noselasdEvery time I watch one of those videos, I imagine how annoying it must be to not be able to release something with zero drift.If I'm ever allowed to be a space tourist, I suspect I'd spend hours just trying to get something to stop drifting relative to the cabin. And then play with water.
⬐ mitchty⬐ dredmorbiusMy first reaction was similar. I started thinking of all the things in life that would be easier to just go, hmm I'll stick this tool here in mid air, space, whatever, and this can go here, etc... But alas, I'll likely never get to experience it.I recall one astronaut addressing this. He'd been on several Shuttle / ISS missions. After his first return to Earth, he was sleeping and, as I recall, his son had climbed into bed with the astronaut and his wife. The astronaut tried to reposition his son by simply pushing him away and releasing him, which didn't work so well.After multiple trips, his adaptation to zero-g / full-g became much more automatic.
Similar, animals used in zero-g experiments seem to adapt to multiple trips. A female mouse learned how to scoot her infants in zero-g.
One article touching on some of this (though I'm remembering another): http://thelede.blogs.nytimes.com/2008/03/11/adapting-to-eart...
NASA TV, http://www.nasa.gov/multimedia/nasatv/index.html, Lot's interesting space things there. Their youtube http://www.youtube.com/user/NASAtelevision channel is also full of fun things.Chris Hadfield's videos and photos from this expedition have been really interesting; his interactions with the public are great and he's answering a lot of fun questions.⬐ zalew⬐ kvprashantyeah, his Google+ feed is amazing. all this expeditions are very expensive and serious, and meanwhile he's like "hey, lets make it fun for everybody down there who's curious. oh hai from space, here's a photo of your city and cool tricks with no gravity".⬐ goyalpulkitHere are his Google+ posts: https://plus.google.com/+ChrisHadfield/posts⬐ kaybehuh. let me cite a speech I heard recently (celebration of 10 years of columbus module in space).. (approximately, it's from my mind) .."The ISS hat two mission objectives, (I) to bring the international community together for collaboration and friendship - this has been accomplished very well, and (II) to do some meaningful science up there, which has not been accomplished at all as of yet. Thus, it's your job to invent meaningful experiments to make the ISS more than a toy." (in the direction of the present students, not the Columbus module team)
What do we learn from this? They need and want input, and they need justification for the expense. The stuff shown here is thus entirely within the official line of the ISS teams.
⬐ kaybe(make that 5 years, sorry)⬐ noselasdWell, there's a lot of science done at the ISS.They're usually running between 100-150 "experiments" at any given time. Most of these do meaningful science. As we all should know, research and science doesn't always lead to something tangible though, but even in the cases it doesn't, it tells a lesson.
Wikipedia lists some of them, http://en.wikipedia.org/wiki/Scientific_research_on_the_Inte..., and just few weeks ago, results from the AMS (http://en.wikipedia.org/wiki/Alpha_Magnetic_Spectrometer) provided some of the most tangible measures we have of dark matter.
⬐ TeMPOraLRE ISS and dark matter, I just accidentally stumbled into this:There were so many wires and electronics in the background and the water was floating everywhere! Nothing to worry?⬐ noselasd⬐ josephlordThe ISS is really packed with lots and lots and lots of things. Here's a tour of the space station: http://www.youtube.com/watch?v=afBm0Dpfj_kThe first half hour, I though "Cool" about pretty much everything, after that my head's starting to hurt thinking about all the things the astronauts need to know where is, what is, how it works, what to do.
⬐ ry0ohkiAll those random messy wires in the background really stressed me out.⬐ ygraSomeone in the comments on that site posted the following video that details how they clean up spills:http://www.youtube.com/watch?v=8Hj3GnPRsJ4
In short: Tissues of various sizes which can then be hanged somewhere and evaporate the water.
⬐ ufmaceInteresting... I was just wondering that after seeing the first video - yeah, that's cool, but what are they going to do now with a soaking washcloth and drops of water floating around all over the place?⬐ ryalfalphaToday I learned the ISS has baby-wipes aboard it.⬐ belornI was really suprised to see them in the original package. One would think they had applied some form of vacuum sealed pressured bag or something to minimize space, or had special designed wipes with material that’s light weight.I guess not everything up there is special space stuff. Some of it is just the same stuff as in the local Grocery store.
⬐ Cthulhu_Reminds me of that famous anecdote where NASA invested a million in developing a pen that could write in zero G, while the Russians used a pencil.⬐ andrewflnr⬐ drharrisApparently, graphite shavings in air filters are bad news. One has to wonder if nice mechanical pencils would be too bad, though.⬐ jclA fictional anecdote, FWIW:Once you have the experience of trying to get a baby wipe out at 3am while a baby is crying, you'll realize they already come pretty close to vacuum sealed. :)⬐ ChrisClarkNot just crying but legs kicking and hands trying to grab their own poo while you try and open a bag of wipes. I think you need 5 arms to handle that situation.⬐ drharrisHaha. It's recently gotten worse at nearly 3yo, because he's much stronger and thinks playing with poo is funny. I've mastered the art of several wrestling holds, could probably go pro.⬐ bhaileHaha. I think a blog article on this would be helpful to me. :) Still learning on holds/wipes/cleaning and how to maximize my two hands.⬐ drharrisUnfortunately I don't think this knowledge is transferable! I recently changed a friend's toddler, and nothing worked. She was a kicker, where my son tends to twist his legs around to gain leverage and flip over. I think it's all stuff you figure out by trial, error, error, and more error.Very cool. One quibble with the title. This is what happens in zero G, I'd love to see the behaviour in space (outside the capsule) too. Does anyone know off the top of their head the state/behaviour of water in the low temperature and low pressure of space?My prediction for the Zero G experiment was that that it would spray in all directions. [Partial spoiler] I was wrong because I forgot about a critical behaviour of water.
⬐ claudius⬐ dbboltonThe phase diagram[0] for water suggests that it will be frozen at 0 Pa and anything less than 200 K, so it will likely form small ice crystals on the cloth. Then trying to wring out the frozen cloth could prove interesting, though.⬐ 4ad⬐ timromanThe water won't have less than 200K when you start the experiment though (else you won't have a wet cloth but a frozen cloth), so all the water will boil off almost instantly.⬐ spinonethirdIt would start boiling but this very fact would very quickly cool it off to freezing point: water has a very high heat of vaporization.⬐ 4ad~72% of the initial water would freeze as ice.Phase #1, water cooling and boiling:
Phase #2, water freezing, remaining water still boiling:mc dT = λv dm dT = λv/(mc) dm | ∫ Tƒ - T₀ = λv/c ∫ (dm/m) = λv/c (ln mƒ' - ln m₀) = = λv/c ln (mƒ'/m₀) ln (mƒ'/m₀) = c/λv (Tƒ - T₀) mƒ'/ m₀ = exp[c/λv (Tƒ - T₀)] mƒ'/m₀ = exp[ 4192J/(kg K) * 1/(2257 * 10^3J/kg) * (-100K)] = = exp[ -4192/2257 * 10^-3 * 10^2 ] = = exp[ -4192/2257 * 10^-1 ] ≈ ≈ 83%.
mƒ = mƒ' - mv |Qced| = Qabs mƒ λc = mv λv mƒ = λv/λc mv mƒ = λv/λc (mƒ' - mƒ) = λv/λc mƒ' - λv/λc mƒ mƒ (1 + λv/λc) = λv/λc mƒ' mƒ = λc/(λc + λv) * λv/λc mƒ' = = λv/(λc + λv) mƒ' mƒ/m₀ = 2257kJ/kg * 1/(2257kJ/kg + 335kJ/kg) * 0.83 ≈ ≈ 2257/2592 * 0.83 ≈ ≈ 72%
⬐ kvprashantWell that escalated quickly!It would probably boil off before it would freeze.⬐ icegreenteaApparently, depends on how much sun you get. If you're in relative darkness, the water would disperse and then freeze into droplets. If you have some sun, the ice would vapourize.http://www.space.com/7274-mystery-explained-glow-night-sky-a...
A bit off topic, but I really feel like this type of "article" adds absolutely nothing to the video. I'd prefer to be linked directly to the video rather than give away a pageview to an entity that isn't even producing its own content.⬐ andrewflnr⬐ lifeisstillgoodI, for one, like to know a little more about what I'm getting into before I watch a video. A video seems like a bigger time commitment than reading some text. If you sent me straight to YouTube, I'm much more likely to just ignore it.⬐ eridiusI disagree. I don't typically watch a video linked on the internet unless I know what it's going to be about. The article let me evaluate the content of the video to determine that I wanted to go ahead and hit play.⬐ dbboltonWith some videos, a bit of context is helpful, but I don't think it was in this case; the text didn't give us much more info than the title. I think Chris Hadfield's videos with the CSA are pretty well-known by now (I have seen several on HN, Reddit, etc.), so I think people would know what they were getting into without the article if the title had been a bit more specific. Granted, with HN's char limit, that isn't always possible.I did a talk yesterday with one of those headset radio mics, and all through that video I kept thinking "I want a floating microphone next time".No matter what you say, a floating microphone will hold the audience :-)
⬐ ozh⬐ lucb1eNo matter what you say, anything floating around you holds the audience. If I were an astronaut, I would just spend all day to goof and play around with everything possible :)⬐ dasil003⬐ sjhHis watch tripped me out.I wonder whether, after he returns to Earth, Cmdr Hadfield will expect things to hang in the air for him; looks habit-forming.⬐ lifeisstillgoodJust be careful if he hands you a beer...⬐ nooneelseThat, and I wonder if he will get bummed out looking at something on a really high shelf, or a cobweb up in an unreachable corner. The old muscle memory quickly telling him how much force to kick off from the floor with to get there. And then his higher brain realizing that he is stuck to the floor. Like a 3-d prisoner forever trapped in Flatland.Upon opening this page, some Kinja registration appeared, suggesting the username Luc0895. My first name is Luc, so I'm extremely curious as to how it knew this. I'm not logged in to io9 nor another Gawker website as far as I know. Anyone else had this?⬐ whatshisface⬐ guybrushTMaybe it was your browser? I've had firefox auto-fill forms on websites I have never been to before.⬐ lucb1e⬐ BognarHmm, that might be it. It sounds weird that Firefox shares personal data, but still they might consider a first name to be non-private. Interesting suggestion, thanks.Are you logged into facebook?⬐ lucb1e⬐ dspillettI don't have Facebook, nor are cookies enabled for FB. Got a cookie killer add-on that only keeps cookies based on a whitelist. And even if I had, how would they obtain my personal data from it without asking my permission?Are they using some form of integration API such as that offered by facebook or G+ for the exchange of comments and likes/+1s?⬐ lucb1eThat's what I'm wondering about, I was never asked for permission to share details with io9. Perhaps a few years ago on another Gawker site, but how would they link me? I wasn't using the same IP or browser or anything.I am logged in to Google+, so that might be it, but it only accepts cookies strictly from accounts.google.com and plus.google.com, for example api.google.com or google.com itself does not work (cookies are removed as soon as all tabs of that website are closed).
Q. What is this video about?A. Its about: Magic. - a cloth unravelling out of a hockey puck - water turning to jello - things and people suspended in air - water flowing against gravity - happening somewhere in space
Magical. An neat little experiment proposed by 2 highschoolers!
⬐ dsuth⬐ ddalexIt still trips me out that we can get video feeds... _from space_Why aren't they concerned about water floating up to the electrical panels ?How do they get dry ? Centrifuges ?
⬐ samolangTL;DW: http://i.imgur.com/myizeus.gif⬐ justx1So it's the surface tension of water.Here is what I am wondering:
Detergents break the surface tension.
What would happen if he'd add some detergent?
⬐ josephagoss⬐ njharmanThe water may not run up his hands? Although I would expect it still to form that water column around the towel thing. Maybe?Just floats his mic. No mic stand required. Not sure why that blows my mind. Driving home that he'd in freaking orbit. Something I "know", but is hard to comprehend.⬐ hadem⬐ nutmegI was wondering when they return to Earth, do they ever just let go of things thinking it will float...? Out of habit I mean.I've noticed in several videos that the crew member appears sweaty or shiny. Is this due to the temperature/humidity in the ISS or because the moisture doesn't evaporate the same way? I'd be interested to know if anyone has an answer.⬐ adimitrov⬐ malandrewIt might (this is conjecture) also just be because they're not wearing any makeup.Absolutely everybody you see on TV is wearing tons of makeup, because cameras paired with artificial flourescent spotlight just seem to exaggerate this nasty shiny effect.
⬐ crazygringoInteresting fact: in the recent Louis CK interview in Rolling Stone, he states that he uses absolutely zero makeup on himself on his show "Louie", which is pretty unusual.⬐ rquantz⬐ corin_His show also benefits when he is portrayed unflatteringly.TV makeup is split into two types, 1) getting people looking good (same reason people wear makeup any time - but if you're being filmed, more people will see you, so you care more) 2) preventing the shineWhile it's true that the lighting often doesn't help, the biggest problem is that the lighting can produce a lot of heat, so it's actually the lights making people sweat, not just making sweat show up more. Not sure lighting on the ISS is likely to do that, but could be wrong.
⬐ sigkillThis leads to another question. Do they (in space) have standard 50Hz/60Hz CFLs? That might be unsafe because of the flicker, right?⬐ DanBCAlexandr Laveikin (cosmonaut) spent time on the Mir (Мир) spacestation in 1987. He said it was "very noisy, very hot."(This is from 'Packing for Mars' by Mary Roach)
I guess heat conduction is difficult if your spacecraft is in a vacuum.
⬐ NegativeK> I guess heat conduction is difficult if your spacecraft is in a vacuum.Very much so. Search for "heat" in this SVG and you'll see the giant accordion radiators: http://upload.wikimedia.org/wikipedia/commons/a/aa/Iss027e03...
When the Space Shuttle was in orbit, it kept its giant bay doors open to expose its radiators.
If you'd like, I can dig up some extensive articlage written for hard sci-fi writers about dealing with heat for engines and for life support.
⬐ TeMPOraLDo dig up those articles please, I'd be interested.⬐ NegativeKHere's the one with lots of basic math around the subject:* http://www.projectrho.com/public_html/rocket/basicdesign.php...
These next two are in regards to dealing with heat in space warfare:
* http://www.projectrho.com/public_html/rocket/spacewarship.ph...
* http://www.projectrho.com/public_html/rocket/spacewardefense...
⬐ TeMPOraLThanks! Awesome stuff.Does anyone else here find it amazing that NASA paid to send a fullsize wireless microphone into space. Given the cost per kilogram of sending things into space, I'm surprised they didn't go with something much smaller/lighter.⬐ eterm⬐ InebasCan you imagine a wired mic in zero g?Given how easily headphones etc tangle in gravity, I'd hate to see what they could do IN SPACE.
⬐ malandrew⬐ cbhlIt doesn't even need to be a wired mic. There are lighter wireless mics available.I would feel wary sending anything smaller, lest it get stuck or lost in some nook somewhere and caused problems.Besides, part of CSA's mandate is to "advance the knowledge of space through science", and sending up cameras and microphones is well within that mandate.
⬐ malandrewI wasn't questioning the sending up of the microphone or video camera. I was just surprised they didn't send up something smaller/lighter. I kind of imagined there there are people who are tasked with "light weighting" everything that is sent on a launch mission so long as the lightweighting doesn't compromise on the engineering integrity of what is being sent into space.Wow! Very interesting stuff but every time I see something interesting, I have more questions than answers. For example, what happens to the fluid in your body? If it floats around, won't we die???⬐ tomflack⬐ bobbo3Which fluids are you talking about specifically? I've very little knowledge of anatomy but I think most of the liquids in our body are in "closed-loop" pressurised systems, with nowhere for the fluid to "go" whilst being forced in to motion by our muscles.That was amazing.On a side note, and not complaining about this at all, how much did it cost to get that water to the space station? I guess that bag had maybe 300 ml?
⬐ raphdg⬐ ajtaylorTissues can be hanged somewhere on a clip, water evaporates, is picked up by dehumidifiers of the spaceship, goes back to the water system and purified back into drinking water.⬐ ygra⬐ barkingcatI guess they meant getting the drinking water to the space station in the first place. Water doesn't really compress well (unlike the hockey puck rag) and also weighs quite a bit so sending it up should be pretty costly.⬐ tempestnHydrogen and Oxygen compress though, and are combined into water in the station's fuel cells.⬐ jfim⬐ queseraYou still need to carry the same mass of hydrogen and oxygen than the resulting mass of water, though.⬐ tempestnMass, yes, but saving volume is also beneficial.It's safe to assume that there is water on premises for other reasons.⬐ akadruid1very roughly, water is $50 million per tonne on the ATV, so (even more approx) $30,000 for the water used in the video.I remember reading that water is generated as a byproduct of the hydrogen fuel cells on board. And then the water vapour is also recycled and repurified back into the system. So it's a closed water system powered by solar energy inputs.Of course, the machinery necessary for this loop costs x billions, but the particular molecules of water used in this experiment probably came out of the internal water cycle and didn't cost to get the water there in the first place.
⬐ barkingcathttp://science.nasa.gov/science-news/science-at-nasa/2000/as...So there is still some loss of water even with the recycling
Am I the only one that now wants to change careers and be an astronaut? This was wicked cool! I was definitely not expecting this result.⬐ NoneNone⬐ sn0vNASA and other space agencies need more funding stat! Private space exploration is fine, but there's something to be said for placing science ahead of company interests.Slightly off topic comment, I know, but watching zero gravity videos makes me realize how awesome space truly is and how little we know about it.
⬐ maxxpowerWhat I love about Chris Hadfields updates are that he is entirely world centric. "400 thousand of us live here" in Countries on the other side of the world. Devoting time not only to Canada and the US but truly communicating the importance of "International" in the title of the ISS.⬐ fourmiiThat was so amazing to watch. Here's a question, and forgive me for my ignorance. What happens to all the water droplets that escaped the washcloth? Aren't they worries about the water finding their way into equipment or electronics?⬐ mbhDid you see his wrist watch? It was fascinating. Like a living organism ...⬐ katherineparkerChris is just awesome. What a good way to get everyone interested and involved in space exploration! There's so many big questions, but the little questions (like this one) are so interesting too.⬐ cyriacthomasChris Hadfield is becoming Internet's the most loved astronaut.⬐ arunabhWhoaa !! we should have videos upon videos for what happens when we do ___ in space :) cc : Elon Musk's spaceX⬐ lessnonymous⬐ NoneI want the blend-tec guy to become an astronaut. "Will it blend IN SPACE?"None⬐ jheimarkspace is amazing.⬐ atechnerdNext experiment: what happens when you sneeze in space?⬐ babooIt would be funnier (and more useful due to deflation) if the government just burned the money that is currently paying for this useless bullshit.⬐ kukrusIt would be funnier (and more useful due to deflation) if the government just burned the money that is currently paying for this useless bullshit.⬐ willismichael⬐ jereRiiiight. Because inspiring the new generation to think about physics (and science in general) is useless </irony>A similar phenomenon makes it dangerous to sleep without proper ventilation:>It is important that crew accommodations be well ventilated; otherwise, astronauts can wake up oxygen-deprived and gasping for air, because a bubble of their own exhaled carbon dioxide has formed around their heads.
http://en.wikipedia.org/wiki/International_Space_Station#Cre...
⬐ eridiusThis sounds like the exact opposite of fan death.⬐ lallysingh⬐ lifeisstillgoodBecause it's real?⬐ jereThe funny part is fans mix gases and prevent exactly the scenario they're accused of causing in fan death (assuming we're talking about asphyxiation and not hypothermia... the hypothermia concern is beyond ridiculous). I don't think I've ever even heard of fan death, but I checked and the issue I mentioned in the OP is actually discussed on the fan death wikipedia page.⬐ hosay123This seems relevant.. old concrete can often emit significant levels of Radon that will tend toward floor level. It's supposedly quite important to properly vent old basements on a semiregular basis for this reason. In such an environment, a fan left running overnight may easily contribute to increased mortality.My first thought on reading "crew quarters must be well ventilated" was - like, opening the windows?Then I remembered.
Luckily I am not on safety critical work for NASA
⬐ ZeccWhen I read "It is important that crew accommodations be well ventilated; otherwise, astronauts can wake up ..." my mind completed with "asphyxiating in a vacuum".