APOD: Wringing a Wet Towel in Orbit (2013 Apr 24)

[APOD Robot]

Wringing a Wet Towel in Orbit

Explanation: What happens if you wring out a wet towel while floating in space? The water shouldn't fall toward the floor because while orbiting the Earth, free falling objects will appear to float. But will the water fly out from the towel, or what? The answer may surprise you. To find out and to further exhibit how strange being in orbit can be, Expedition 35 Commander Chris Hadfield did just this experiment last week in the microgravity of the Earth orbiting International Space Station. As demonstrated in the above video, although a few drops do go flying off, most of the water sticks together and forms a unusual-looking cylindrical sheath in and around the towel. The self-sticking surface tension of water is well known on Earth, for example being used to create artistic water cascades and, more generally, raindrops.

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[bystander]

http://asterisk.apod.com/viewtopic.php?t=31154

"Hey, you sass that hoopy Ford Prefect? There's a frood who really knows where his towel is." ~ Douglas Adams

[Wakaleo]

That's a cool experiment! But no one seems concerned about the stray drops of water. Couldn't they be a hazard to electrical components, particularly as they could break up into droplets small enough to infiltrate just about anywhere? I would have thought capillary action could also draw the water deep inside the components. Surely the entire ISS is not water-proof!

And Bystander, you beat me to it with the THGG quote.

[borc]

My guess is he is inside one of the sections of the ship where there arent too many tech gadgets everywhere. he also has a dude close by who probably helped him snag most of the drops, leaving not much more than would have been there from a strong cough.

i could be wrong, but chances are Mr Hadfield thought of that.

[alter-ego]

That's a cool experiment! But no one seems concerned about the stray drops of water. Couldn't they be a hazard to electrical components, particularly as they could break up into droplets small enough to infiltrate just about anywhere? I would have thought capillary action could also draw the water deep inside the components. Surely the entire ISS is not water-proof!

And Bystander, you beat me to it with the THGG quote.

Well I can't speak for the electronics for sure, but there are places that are

Edit: On that note though, space qualified electronics are "hardened" far beyond our every-day electronics. The fact is, mil-qualified electronics are designed and built to perform in really egregious (bad) environments. However, the hoops hardware and electronics must pass is expensive. That said, I'll bet no one's worried about a few small drops of water. I've never seen an astronaut demonstrate spraying a water bottle like a loose cannon either, so I do think their level of care is just not at the few-drop level. As far as moisture protection goes, the electronics are likely conformal coated.

[Ann]

This is a really fun and thought-provoking video. I'm not exactly sure how, but I can't help thinking that this video says something about why water is so essential to life on Earth. Between the gravity of the Earth and the surface tension of liquid water, this fluid is just the ticket for biological life on Earth!

Ann

[Beyond]

Maybe that's why humans are mostly water. I would imagine that it is that way for all the other critters also, but have only seen it expressed for humans. So if you are a physical BEing, then you are mostly all wet.

[neufer]

http://asterisk.apod.com/viewtopic.php?t=31154

"Hey, you sass that hoopy Ford Prefect? There's a frood who really knows where his towel is." ~ Douglas Adams

"A towel, it says, is about the most massively useful thing an interstellar hitchhiker can have. Partly it has great practical value - you can wrap it around you for warmth as you bound across the cold moons of Jaglan Beta; you can lie on it on the brilliant marble-sanded beaches of Santraginus V, inhaling the heady sea vapours; you can sleep under it beneath the stars which shine so redly on the desert world of Kakrafoon; use it to sail a mini raft down the slow heavy river Moth; wet it for use in hand-to- hand-combat; wrap it round your head to ward off noxious fumes or to avoid the gaze of the Ravenous Bugblatter Beast of Traal (a mindboggingly stupid animal, it assumes that if you can't see it, it can't see you - daft as a bush, but very ravenous); you can wave your towel in emergencies as a distress signal, and of course dry yourself off with it if it still seems to be clean enough.

More importantly, a towel has immense psychological value. For some reason, if a strag (strag: non-hitch hiker) discovers that a hitch hiker has his towel with him, he will automatically assume that he is also in possession of a toothbrush, face flannel, soap, tin of biscuits, flask, compass, map, ball of string, gnat spray, wet weather gear, space suit etc., etc. Furthermore, the strag will then happily lend the hitch hiker any of these or a dozen other items that the hitch hiker might accidentally have "lost". What the strag will think is that any man who can hitch the length and breadth of the galaxy, rough it, slum it, struggle against terrible odds, win through, and still knows where his towel is is clearly a man to be reckoned with."

[Whiskybreath]

Canadians in space? Whatever next?

[rstevenson]

Canadians in space? Whatever next?

You are apparently unaware that we control the world.

Rob

[neufer]

Click to play embedded YouTube video.

Canadians in space? Whatever next?

You are apparently unaware that we control the world.

Rob

In the future, perhaps.

[Psnarf]

When I first viewed this video a couple of days ago, I guessed that small water globules would squirt out in all directions, much like the two-dimensional spray on earth rotated 360-d about the horizontal axis of the towel. I should have known that the surface tension of water would have interfered with that, having once calibrated a surface tensiometer sensitive to the local gravitational force. How soon we forget!

(Any loose water droplets would end up in the air intake vents and filtered out.)

[H Wheeler]

Thinking about swimming in a swimming pool in space for the first time is pretty funny. Would it stick to the walls and create a breathable space in the middle or create a big bubble in the middle that bounces off the walls as the swimmer tries to get into the water?

[neufer]

Thinking about swimming in a swimming pool in space for the first time is pretty funny. Would it stick to the walls and create a breathable space in the middle or create a big bubble in the middle that bounces off the walls as the swimmer tries to get into the water?

[b][color=#0000FF]A specimen chamber housing Medaka fish for study in the Aquatic Habitat. Photo: JAXA[/color][/b]

---

"A first for fish in space"
James W. Manning, WAtoday, July 31, 2012

<<The Japanese Space Agency (JAXA) has sent an aquarium to the International Space Station. No, this isn't a veiled attempt at turning the ISS into some kind of swanky bachelor pad, but rather an experiment that will study the effects of microgravity on marine life. Specifically, researchers will examine the impacts of radiation, bone degradation, muscle atrophy and developmental biology over a three-month period. This data may improve understanding of human health in these areas back on Earth.

"We think studies on bone degradation mechanisms and muscle atrophy mechanisms are applicable to human health problems, especially for the ageing society," said Nobuyoshi Fujimoto, associate senior engineer at JAXA.

Scientists will examine small, freshwater fish in orbit, starting with the Medaka fish (Oryzias latipes). Medaka are ideal specimens because they are transparent, which makes light work of observing the workings of their inner organs. They are also quick breeders, allowing the studies to examine different generations of the fish. The animal's genome is already fully sequenced, making it easy to recognises changes in their genes.

The Aquatic Habitat, or AQH, was sent into space on July 20 [2012] and will reside in the Japanese Experiment Module, also known as 'Kibo', which is Japanese for 'hope'. While water habitats have been sent into space before, this system features an improved circulation system that monitors water conditions, removes waste and improves oxygen flow. The habitat also includes temperature control and an automatic feeding system for the fish, while day and night cycles will be simulated by LED lighting. Video cameras will stream vision of the fish back to Earth for further analysis. "The special bacteria filter purifies waste materials, such as ammonia, so that we can keep fish for up to 90 days," said Mr Fujimoto. "This capability will make it possible for egg-to-egg breeding aboard station, which means up to three generations may be born in orbit. This would be a first [for fish] in space."

If space fish aren't quite cool enough for you, space frogs could be next on the agenda. The air-water interface design of the Aquatic Habitat makes it possible to house amphibious animals too.>>

[oerz]

What I am wondering is whether Commander Chris Hadfield's wrist watch was fitting snugly when he left earth. If so, I am amazed how much loses muscle mass in space!

[JohnD]

As was said in the video and here, great experiment!

Commander Hadfield complimented "Meredith and Kendrick" on their suggestion, so I think they should get a credit here too!
School kids? Well done!

John

[LocalColor]

Smart kids, great experiment and enjoyable video!

[neufer]

Click to play embedded YouTube video.

As was said in the video and here, great experiment!

Commander Hadfield complimented "Meredith and Kendrick" on their suggestion, so I think they should get a credit here too!

School kids? Well done!

Smart kids, great experiment and enjoyable video!

[SevenEagles]

Nice manicure.

[Boomer12k]

This is a really fun and thought-provoking video. I'm not exactly sure how, but I can't help thinking that this video says something about why water is so essential to life on Earth. Between the gravity of the Earth and the surface tension of liquid water, this fluid is just the ticket for biological life on Earth!

Ann

Water is a solvent. It helps break things down, so they can mingle chemically. So water is a medium. I think the surface tension helps hold on to things. Cells have electricity. A positive charged nucleus, a negative charged membrane. (except blood cells, which have no nucleus evidently.) Water conducts electricity....thus it is essential to the working of the cell, and chemistry of the body, and other life as well...Life is CELLS...A Cell is the Quantum of life. Best invention/adaptation in the Universe? Cellulose...The most common organic compound on Earth. A skin to hold water, and the nucleus, and allows the flow of energy, and nutrients from the body systems to all the cells...the biggest Miracle...GOTTA HAVE A CONTAINER!!!!!

Gravity would help with the mixing...static weightlessness would have no motion...

My opinion and observation.
:---[===] *

[Beyond]

Sounds wet to me Good gurgling, Boomer 12k.

[NoelC]

What fun!

Training aside, I wonder how long it takes to get used to how different everything is in a zero-G environment.

-Noel

[neufer]

Click to play embedded YouTube video.

What fun!

Training aside, I wonder how long it takes to get used to how different everything is in a zero-G environment.

-Noel

[JohnD]

[quote="Boomer12k A positive charged nucleus, a negative charged membrane. (except blood cells, which have no nucleus evidently.) [/quote]

Ummmmmm.
Not quite the whole picture, Boomer.
The cell membrane contains ion pump protein complexes that remove Sodium from the cell and push Potassium in. The balance of this ion exchnage is not equal, so the inside of the cell is negative in relation to the outside. This 'resting potential' is about 50mV.
The nucleus has the same bilipid layer as the cell membrane around it, again dotted with ion pumps, that maintain a resting potential across the nuclear membrane, but at only 15mV, with again positive on the outside.
So I'm afraid for you that the attractive idea of a negative outside with a positive nucleus isn't true. That's atoms!
The cell is positive on the outside and negative on the inside of its outer memberane, and the nucleus at its membrane is the same!

John

[DavidLeodis]

Wow that is a fascinating experiment and video. Almost eerie seeing the water over Chris's hands.

The wiring on the International Space Station does look 'untidy'. I hope nobody gets caught in it but I wonder what would happen if they do . I presume it is possible to be strangled in weightlessness.