Water, in space, will not flow. It will not cascade, or drip, or fill a cup. Instead, unimpeded by gravity, water tends to collect in floating blobs that are works of beauty and science at the same time.
But what happens when a) you're in space and b) you find yourself with a wet washcloth and c) you try to wring it out?
The answer is that your attempt will be unsuccessful, because the water wants to stay far more than you want it to go. The latest evidence of that comes from the video above, featuring Space Station astronaut Chris Hadfield and a washcloth that has absorbed a large amount of water. And the liquid, save for a few errant blobs, clings to the washcloth instead of flowing to the ground. It forms a kind of tube over the cloth, as well as over the human hands that hold it. It is not going anywhere.
That's because of the surface tension of the water. Unimpeded by gravity, the water's molecules cohere, creating a kind of liquid gel. It's almost, Hadfield says, "like you had Jell-O on your hands."
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