When Helium is cooled to almost absolute zero (-460°F or -273°C, the lowest temperature possible), it becomes a liquid with surprising properties: it flows against gravity and will start running up and over the lip of a glass container!
We all know helium as a gas for blowing up balloons and making people talk like chipmunks, but what most people don’t know is that it comes in two distinct liquid states — one of which is borderline creepy. When helium is just a few degrees below its boiling point of –452°F (–269°C), it can suddenly do things that other fluids can’t, like dribble through molecule-thin cracks, climb up and over the sides of a dish, and remain motionless when its container is spun. No longer a mere liquid, the helium has become a superfluid — a liquid that flows without friction.
“If you set [down] a cup with a liquid circulating around and you come back 10 minutes later, of course, it’s stopped moving,” says John Beamish, an experimental physicist at the University of Alberta in Edmonton.
This happens because atoms in the liquid will collide with one another and slow down.
“But if you did that with helium at low temperature and came back a million years later,” he says, “it would still be moving”.
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